JP7472378B2 - Content protection processing method - Google Patents

Description

The present invention relates to a broadcast receiving device.

One of the expanded functions of digital broadcasting services is data broadcasting, which transmits digital data via broadcast waves and displays various information such as weather forecasts, news, and recommended programs. Many television receivers capable of receiving data broadcasting are already commercially available, and many technologies related to receiving data broadcasting have been published, including Patent Document 1 below.

JP 2001-186486 A

In response to recent changes in the content distribution environment, television receivers are also being asked to expand their functions in various ways. In particular, there are many demands for the distribution of content and linked applications using broadband network environments such as the Internet, as well as for higher resolution and definition video content. However, it is difficult to provide a high-added-value television receiver that can meet these demands by simply reusing the data broadcasting reception function and other functions that are equipped in current television receivers, or by simply expanding the functions of said data broadcasting reception function and other functions.

The object of the present invention is to provide a broadcast receiving device capable of executing functions with higher added value.

The technology described in the claims is used as a means to solve the above problems.

As an example, a content protection processing method in a transmission system in which broadcast program content is transmitted from a broadcast station and received by a broadcast receiving device, the method includes a transmission step in the transmission system in which the broadcast program content is transmitted from the broadcast station to the broadcast receiving device, a reception step in which the broadcast receiving device receives the broadcast program content transmitted by the transmission system, a storage step in which the broadcast receiving device stores the broadcast program content received in the reception step, a copy processing step in which the broadcast receiving device copies the broadcast program content stored in the storage step, and a move processing step in which the broadcast receiving device moves the broadcast program content stored in the storage step, and in the storage step, When the broadcast program content received in the above step is content that has been transmitted in the transmission system with protection that allows a predetermined number of copies, the broadcast program content is stored in a state in which nine copies and one move process are possible for the broadcast program content, and in the copy process step, when the broadcast program content stored in the storage step is copied to an external device, content protection is performed using DTCP2, and copying is possible using the move process function of DTCP2, and storage in the storage step can be performed in a storage unit at the output destination of an IP interface configured with Ethernet-compatible hardware provided in the broadcast receiving device.

By using the technology of the present invention, it is possible to provide a broadcast receiving device that can perform functions with higher added value.

1 is a configuration diagram of a broadcast communication system including a broadcast receiving device according to a first embodiment. FIG. 1 is an explanatory diagram of components of an encoded signal in MMT. FIG. 1 is a configuration diagram of an MPU in MMT. FIG. 1 is a diagram illustrating the structure of an MMTP packet in MMT. A conceptual diagram of a protocol stack of a broadcasting system using MMT. FIG. 1 is a diagram showing a hierarchical structure of control information used in a broadcasting system. This is a list of tables used in the TLV-SI of the broadcasting system. This is a list of descriptors used in the TLV-SI of the broadcasting system. This is a list of messages used in MMT-SI of the broadcasting system. This is a list of tables used in MMT-SI of the broadcasting system. This is a list (1) of descriptors used in MMT-SI of the broadcasting system. This is a list (2) of descriptors used in MMT-SI of the broadcasting system. This is a list (3) of descriptors used in MMT-SI of the broadcasting system. FIG. 2 is a diagram showing the relationship between the components of a broadcasting system and each table. A diagram showing the data structure of the MPT of the broadcasting system. A diagram showing the data structure of location information of a broadcasting system. A diagram showing the data structure of an MPU timestamp descriptor in a broadcasting system. A diagram showing the data structure of MH-EIT of a broadcasting system. A diagram showing the data structure of an event package descriptor for a broadcasting system. 1 is a block diagram of a broadcast receiving device according to a first embodiment. 2 is a configuration diagram of a logical plane structure of a presentation function of the broadcast receiving device according to the first embodiment. FIG. FIG. 2 is a software configuration diagram of the broadcast receiving device according to the first embodiment. FIG. 2 is a block diagram of a broadcasting station server according to the first embodiment. FIG. 2 is a block diagram of a service provider server according to the first embodiment. FIG. 1 is a block diagram of a portable information terminal according to a first embodiment. FIG. 2 is a software configuration diagram of the portable information terminal according to the first embodiment. 1 is a system configuration diagram of clock synchronization/presentation synchronization of a broadcast receiving device according to a first embodiment. A diagram showing the data structure of the NTP format of a broadcasting system. A diagram showing the data structure of MH-TOT of a broadcasting system. A diagram showing the format of the JST_time parameter of a broadcasting system. A diagram showing the data structure of time information in the TMCC extended information area of a broadcasting system. 11 is a diagram showing a method of calculating the current date from the MJD of the broadcast receiving device in Example 1. 4 is an operational sequence diagram of the broadcast receiving device according to the first embodiment during channel scanning. FIG. A diagram showing the data structure of the TLV-NIT of a broadcasting system. A diagram showing the data structure of a satellite distribution system descriptor of a broadcasting system. A diagram showing the data structure of a service list descriptor for a broadcasting system. A diagram showing the data structure of AMT of a broadcasting system. 4 is a diagram showing an operation sequence when the broadcast receiving device according to the first embodiment selects a channel. FIG. A conceptual diagram explaining reference to the MPT of each package by the PLT of a broadcasting system. A diagram showing the data structure of a PLT of a broadcasting system. 1 is an external view of a remote control capable of controlling a broadcast receiving device in accordance with a first embodiment. A diagram showing the data structure of a remote control key descriptor of a broadcasting system. FIG. 10 is a diagram illustrating a process of selecting multiple channels. FIG. 11 is a diagram illustrating an angle selection process for a multi-view compatible program. A diagram showing the data structure of the LCT of a broadcasting system. A diagram showing the data structure of an MPU presentation area designation descriptor for a broadcasting system. FIG. 13 illustrates the assignment of layouts to layout numbers based on the LCT. FIG. 13 illustrates the assignment of layouts to layout numbers based on the LCT. FIG. 13 illustrates the assignment of layouts to layout numbers based on the LCT. FIG. 13 illustrates the assignment of layouts to layout numbers based on the LCT. 13 is a diagram for explaining exception handling of screen layout control based on LCT. 13 is a diagram for explaining exception handling of screen layout control based on LCT. A diagram showing the data structure of a video component descriptor of a broadcasting system. 13 is a diagram for explaining the meaning of the video signal aspect ratio of the video component descriptor. FIG. 4A to 4C are diagrams illustrating the aspect ratio conversion process of the broadcast receiving device according to the first embodiment. 4A to 4C are diagrams illustrating the aspect ratio conversion process of the broadcast receiving device according to the first embodiment. FIG. 2 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 2 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 2 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. 4 is a screen display diagram of the broadcast receiving device according to the first embodiment when an emergency alert broadcast is displayed. FIG. A diagram showing the data structure of a content copy control descriptor for a broadcasting system. FIG. 13 is a diagram showing the meaning of copy control information in a content copy control descriptor. A diagram showing the data structure of a content usage control descriptor for a broadcasting system. FIG. 11 is a block diagram of a broadcast receiving device according to a second embodiment. 11A and 11B are diagrams illustrating inconsistencies in the current time display when switching broadcast services. 13A and 13B are diagrams illustrating the operation of current time information reference source selection control according to the second embodiment. FIG. 11 is an operation sequence diagram of a current time information update process according to the second embodiment. FIG. 11 is a screen display diagram of an EPG screen of a broadcast receiving device according to a second embodiment. FIG. 11 is a screen display diagram of an EPG screen of a broadcast receiving device according to a second embodiment. FIG. 11 is a diagram illustrating a content protection process according to a third embodiment. FIG. 13 is a diagram illustrating a content protection process according to a fourth embodiment.

Below, an example embodiment of the present invention will be described with reference to the drawings.

Example 1
[System configuration]
1 is a system configuration diagram showing an example of a broadcast communication system including a broadcast receiving device of this embodiment. The broadcast communication system of this embodiment is composed of a broadcast receiving device 100, an antenna 100a, a broadband network such as the Internet 200, a router device 200r, an access point 200a, a radio tower 300t of a broadcast station, a broadcast satellite (or a communication satellite) 300s, a broadcast station server 300, a service provider server 400, other application servers 500, a mobile telephone communication server 600, a base station 600b of a mobile telephone communication network, and a mobile information terminal 700.

The broadcast receiving device 100 receives broadcast waves transmitted from a radio tower 300t via a broadcast satellite (or communication satellite) 300s and an antenna 100a. Alternatively, the broadcast waves transmitted from the radio tower 300t may be received directly from the antenna 100a without passing through the broadcast satellite (or communication satellite) 300s. The broadcast receiving device 100 can also be connected to the Internet 200 via a router device 200r, and can transmit and receive data by communicating with each server device and other communication devices on the Internet 200.

The router device 200r is connected to the Internet 200 by wired communication, to the broadcast receiving device 100 by wired communication or wireless communication, and to the mobile information terminal 700 by wireless communication. The wireless communication may use a method such as Wi-Fi (registered trademark). This allows each server device and other communication devices on the Internet 200 to transmit and receive data to and from the broadcast receiving device 100 and the mobile information terminal 700 via the router device 200r. Note that communication between the broadcast receiving device 100 and the mobile information terminal 700 may be performed directly using a method such as BlueTooth (registered trademark) or NFC (Near Field Communication) without going through the router device 200r.

The radio tower 300t is a broadcasting facility of a broadcasting station, and transmits broadcast waves including encoded data and subtitle information of broadcast programs, other applications, general-purpose data, etc. The broadcasting satellite (or communication satellite) 300s is a repeater that receives broadcast waves transmitted from the radio tower 300t of the broadcasting station, performs appropriate frequency conversion, etc., and then retransmits the broadcast waves to the antenna 100a connected to the broadcast receiving device 100. The broadcasting station is also assumed to have a broadcasting station server 300. The broadcasting station server 300 stores broadcast programs (video content, etc.) and metadata such as the program title, program ID, program summary, performer information, broadcast date and time of each broadcast program, and is capable of providing the video content and each metadata to a service provider based on a contract. The video content and each metadata may be provided to the service provider through an API (Application Programming Interface) provided by the broadcasting station server 300.

The service provider server 400 is a server device prepared by a service provider, and is capable of providing various services linked to broadcast programs distributed by a broadcast station. The service provider server 400 also stores, manages, and distributes video content and metadata provided by the broadcast station server 300, as well as various content and applications linked to broadcast programs. It also has a function of searching for and providing a list of available content and applications in response to inquiries from television receivers, etc. The storage, management, and distribution of the content and metadata and the storage, management, and distribution of the applications may be performed by different server devices. The broadcast station and the service provider may be the same or different. A plurality of service provider servers 400 may be prepared for each different service. The functions of the service provider server 400 may also be provided by the broadcast station server 300.

The other application server 500 is a known server device that stores, manages, and distributes other general applications, operating programs, content, data, etc. There may be multiple other application servers 500 on the Internet 200.

The mobile telephone communication server 600 is connected to the Internet 200, and is also connected to the mobile information terminal 700 via the base station 600b. The mobile telephone communication server 600 manages telephone communication (calls) and data transmission and reception via the mobile telephone communication network of the mobile information terminal 700, and enables data transmission and reception by communication between the mobile information terminal 700 and each server device on the Internet 200 and other communication devices. The communication between the base station 600b and the mobile information terminal 700 may be performed by the W-CDMA (Wideband Code Division Multiple Access) (registered trademark) system, the GSM (Global System for Mobile communications) (registered trademark) system, the LTE (Long Term Evolution) system, or other communication systems.

The mobile information terminal 700 has a function of telephone communication (calls) and data transmission and reception via a mobile telephone communication network, and a function of wireless communication by Wi-Fi (registered trademark) or the like. The mobile information terminal 700 can be connected to the Internet 200 via the router device 200r or the access point 200a, or via the base station 600b of the mobile telephone communication network and the mobile telephone communication server 600, and can transmit and receive data by communication with each server device on the Internet 200 and other communication devices. The access point 200a is connected to the Internet 200 by wired communication, and is connected to the mobile information terminal 700 by wireless communication. The wireless communication may be a method such as Wi-Fi (registered trademark). The communication between the mobile information terminal 700 and the broadcast receiving device 100 may be performed via the access point 200a, the Internet 200, and the router device 200r, or via the base station 600b, the mobile telephone communication server 600, the Internet 200, and the router device 200r.

[Overview of the MMT method]
The broadcast receiving device 100 shown in Fig. 1 is a television receiver that is compatible with MMT (MPEG Media Transport) instead of TS (Transport Stream) (hereinafter, referred to as MPEG2-TS) defined in the MPEG (Moving Picture Experts Group)-2 system, which is widely adopted in conventional digital broadcasting systems as a media transport method for transmitting data such as video and audio. The television receiver may be compatible with both MPEG2-TS and MMT.

MPEG2-TS is characterized by multiplexing the video, audio, and other components that make up a program into a single stream along with control signals and a clock. As the clock is also treated as a single stream, it is suitable for transmitting a single piece of content over a single transmission path with guaranteed transmission quality, and has been adopted in many conventional digital broadcasting systems. However, in recent years, there has been a diversification of content, diversification of devices that use content, diversification of transmission paths for distributing content, diversification of content storage environments, and other changes in the content distribution environment. As a result, MPEG2-TS has limitations in its functionality, and a newly developed media transport method is MMT.

Figure 2A shows an example of an outline of an encoded signal in the MMT of this embodiment. As shown in the figure, the MMT of this embodiment has the following elements constituting the encoded signal: MFU (Media Fragment Unit), MPU (Media Processing Unit), MMTP (MMT Protocol) payload, and MMTP packet.

The MFU is a format for transmitting video, audio, etc., and may be configured in NAL (Network Abstraction Layer) units or access units. The MPU includes one or more access units, and is capable of performing video and audio decoding processing by itself. The MPU may be configured with MPU metadata including information on the overall configuration of the MPU, movie fragment metadata including information on the encoded media data, and sample data which is encoded media data. A single MPU may have multiple pieces of movie fragment data and sample data. Also, it is assumed that it is possible to extract the MFU from the sample data. FIG. 2B shows an example of the configuration of an MPU. Note that by adding a sequence number to each MPU belonging to the same asset, it is assumed that any MPU can be distinguished from other MPUs by the asset ID that identifies the asset and the sequence number of the MPU. Also, in the case of media such as video components and audio components, the presentation time and decoding time may be specified on an MPU or access unit basis.

The MMTP packet is composed of a header section and an MMTP payload, and transmits control information of the MFU and MMT. The MMTP payload is equipped with a payload header according to the contents (data units) to be stored in the payload section. FIG. 2C shows an example of an overview of constructing an MFU from a video/audio signal, storing it in the MMTP payload, and constructing an MMTP packet. In addition, in a video signal that is encoded using inter-frame prediction, it is desirable to configure the MPU in GOP (Group Of Pictures) units. In addition, when the size of the MFU to be transmitted is small, one MFU may be stored in one payload section, or multiple MFUs of the same type may be stored in one payload section. In addition, when the size of the MFU to be transmitted is large, one MFU may be divided and stored in multiple payload sections. In addition, MMTP packets may be protected using techniques such as AL-FEC (Application Layer Forward Error Correction) and ARQ (Automatic Repeat Request) to recover from packet loss on the transmission path.

In the broadcasting system of this embodiment, MPEG-H HEVC (High Efficiency Video Coding) is used as the video encoding method, and MPEG-4 AAC (Advanced Audio Coding) or MPEG-4 ALS (Audio Lossless Coding) is used as the audio encoding method. The encoded data of the video and audio of the broadcast program encoded by each of the above methods is in the format of MFU or MPU, and is further loaded on the MMTP payload to be packetized as MMTP packets and transmitted in IP (Internet Protocol) packets. In addition, data content related to the broadcast program may also be in the format of MFU or MPU, and further loaded on the MMTP payload to be packetized as MMTP packets and transmitted in IP packets. Four types of data content transmission methods are provided: (1) a subtitle/superimposed text transmission method used for streaming data synchronized with broadcasting; (2) an application transmission method used for data transmission services asynchronous with broadcasting; (3) an event message transmission method used for synchronous/asynchronous message notifications from broadcasting stations to applications running on television receivers; and (4) a general-purpose data transmission method for transmitting other general-purpose data synchronously/asynchronously.

For the transmission of MMTP packets, UDP/IP (User Datagram Protocol/Internet Protocol) is used on the broadcast transmission path, and UDP/IP or TCP/IP (Transmission Control Protocol/Internet Protocol) is used on the communication line. In addition, the TLV (Type Length Value) multiplexing method is used on the broadcast transmission path for efficient transmission of IP packets. An example of a protocol stack for the broadcast system of this embodiment is shown in Figure 3. In the figure, (A) is an example of a protocol stack on the broadcast transmission path, and (B) is an example of a protocol stack on the communication line.

In the broadcasting system of this embodiment, a mechanism is provided for transmitting two types of control information: MMT-SI (MMT-Signaling Information) and TLV-SI (TLV-Signaling Information). MMT-SI is control information that indicates the configuration of a broadcast program, etc. It is in the form of an MMT control message, placed on an MMTP payload, packetized as an MMTP packet, and transmitted in an IP packet. TLV-SI is control information related to multiplexing of IP packets, and provides information for channel selection and correspondence information between IP addresses and services.

In addition, in broadcasting systems using MMT, time information is also transmitted to provide absolute time. Note that while MPEG2-TS indicates the display time of components based on a different clock for each TS, MMT indicates the display time of components based on Coordinated Universal Time (UTC). These mechanisms enable terminal devices to synchronize and display components transmitted from different transmission points over different transmission paths. To provide UTC, IP packets in NTP (Network Time Protocol) format are used.

[Control information for broadcasting systems using MMT]
In the broadcasting system supported by the broadcasting receiving device 100 of this embodiment, as described above, TLV-SI related to the TLV multiplexing method for multiplexing IP packets and MMT-SI related to MMT, which is a media transport method, are prepared as control information. TLV-SI provides information for the broadcasting receiving device 100 to demultiplex IP packets multiplexed on a broadcast transmission path. TLV-SI is composed of a "table" and a "descriptor". The "table" is transmitted in a section format, and the "descriptor" is placed in the "table". MMT-SI is transmission control information indicating the configuration of an MMT package and information related to a broadcasting service. MMT-SI is composed of three layers: a "message" that stores a "table" or a "descriptor", a "table" that has elements and attributes that indicate specific information, and a "descriptor" that indicates more detailed information. An example of the hierarchical configuration of control information used in the broadcasting system of this embodiment is shown in FIG. 4.

<Tables used in TLV-SI>
5A shows a list of "tables" used in the TLV-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. In this embodiment, the following are used as the "tables" of the TLV-SI.

(1) TLV-NIT
A Network Information Table for TLV (TLV-NIT) represents information about the physical configuration of the TLV stream transmitted by the network and the characteristics of the network itself.

(2) AMT
The Address Map Table (AMT) provides a list of multicast groups for the IP packets that constitute each service transmitted in the network.

(3) Tables Set by Service Providers In addition, service providers and the like can prepare tables that they set independently.

<Descriptors used in TLV-SI>
5B shows a list of "descriptors" placed in the TLV-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. In this embodiment, the following "descriptors" are used as the TLV-SI "descriptors".

(1) Service List Descriptor The service list descriptor provides a list of services by service identification and service format type.

(2) Satellite Distribution System Descriptor The satellite distribution system descriptor indicates the physical conditions of the satellite transmission path.

(3) System Management Descriptor The system management descriptor is used to distinguish between broadcast and non-broadcast.

(4) Network Name Descriptor The network name descriptor describes the network name using character codes.

(5) Remote Control Key Descriptor The remote control key descriptor is used to set a service to be assigned to a one-touch channel selection button on the receiver remote control.

(6) Descriptors Set by Service Providers In addition, service providers etc. may prepare their own unique descriptors.

<Messages used in MMT-SI>
6A shows a list of "messages" used in MMT-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. In this embodiment, the following are used as "messages" of MMT-SI.

(1) PA Message The Package Access (PA) message is used to transmit various tables.

(2) M2 Section Message The M2 section message is used to transmit the section extension format of the MPEG-2 Systems.

(3) CA Message The CA message is used to transmit a table for identifying the conditional access system.

(4) M2 Short Section Message The M2 short section message is used to transmit the section short format of the MPEG-2 Systems.

(5) Data Transmission Message A data transmission message is a message that stores a table related to data transmission.

(6) Messages Set by Service Providers In addition, service providers and the like can prepare messages that they set independently.

<Tables used in MMT-SI>
6B shows a list of "tables" used in the MMT-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. A table is control information having elements and attributes indicating specific information, and is stored in a message and transmitted in an MMTP packet. Note that the message that stores the table may be determined according to the table. In this embodiment, the following is used as the "table" of MMT-SI.

(1) MPT
The MMT Package Table (MPT) provides information that configures a package, such as a list of assets, the location of the assets on the network, etc. The MPT may be stored in a PA message.

(2) PLT
A package list table (PLT) indicates a list of IP data flows and packet IDs that transmit PA messages of MMT packages provided as broadcast services, and IP data flows that transmit IP services. The PLT may be stored in the PA message.

(3) LCT
A Layout Configuration Table (LCT) is used to associate layout information for presentation with a layout number. The LCT may be stored in the PA message.

(4) ECM
An Entitlement Control Message (ECM) is common information consisting of program information and control information, and delivers key information for descrambling, etc. The ECM may be stored in an M2 section message.

(5) EMM
An Entitlement Management Message (EMM) transmits individual information including contract information for each subscriber, key information for decrypting ECM (common information), etc. The EMM may be stored in an M2 section message.

(6) CAT (MH)
A Conditional Access Table (CAT) (MH) is used to store a descriptor for identifying a conditional access system. The CAT (MH) may be stored in a CA message.

(7) DCM
A Download Control Message (DCM) transmits key-related information including a key for decrypting a transmission line encryption for downloading. The DCM may be stored in an M2 section message.

(8) DMM
A Download Management Message (DMM) transmits key-related information such as a download key for decrypting a DCM. The DMM may be stored in an M2 section message.

(9) MH-EIT
The MH-Event Information Table (MH-EIT) is time-series information on events included in each service. The MH-EIT may be stored in the M2 section message.

(10) MH-AIT
The MH-Application Information Table (MH-AIT) stores all information related to applications and their required activation states, etc. The MH-AIT may be stored in the M2 section message.

(11) MH-BIT
The MH-BIT (MH Broadcaster Information Table) is used to present information on broadcasters present on the network. The MH-BIT may be stored in the M2 section message.

(12) MH-SDTT
The MH-Software Download Trigger Table (MH-SDTT) is used for download notification information. The MH-SDTT may be stored in the M2 section message.

(13) MH-SDT
The MH-Service Description Table (MH-SDT) has sub-tables that indicate services included in a specific TLV stream, and transmits information about the channel, such as the name of the channel, the name of the broadcaster, etc. The MH-SDT may be stored in the M2 section message.

(14) MH-TOT
The MH-Time Offset Table (MH-TOT) carries JST time and date (Modified Julian Date) information. The MH-TOT may be stored in the M2 short section message.

(15) MH-CDT
The MH-Common Data Table (MH-CDT) is used to transmit common data to be stored in a non-volatile memory in section format for all receivers that receive the MH-CDT. The MH-CDT may be stored in an M2 section message.

(16) DDM Table The Data Directory Management Table (DDM table) provides a directory structure of files that configure an application in order to separate the file structure of the application from the structure for file transmission. The DDM table may be stored in a data transmission message.

(17) DAM Table The Data Asset Management Table (DAM table) provides the configuration of MPUs in an asset and version information for each MPU. The DAM table may be stored in a data transmission message.

(18) DCC Table The Data Content Configuration Table (DCC table) provides configuration information of files as data contents to realize flexible and effective cache control. The DCC table may be stored in a data transmission message.

(19) EMT
The Event Message Table (EMT) is used to transmit information about event messages. The EMT may be stored in the M2 section message.

(20) Tables Set by Service Providers In addition, service providers and the like can prepare tables that they set independently.

<Descriptors used in MMT-SI>
6C, 6D, and 6E show a list of "descriptors" arranged in the MMT-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. The descriptor is control information that provides more detailed information, and is arranged in a table. The table in which the descriptor is arranged may be determined according to the descriptor. In this embodiment, the following are used as "descriptors" of the MMT-SI.

(1) Asset Group Descriptor The asset group descriptor provides the group relationship of assets and the priority within the group. The asset group descriptor may be placed in the MPT.

(2) Event Package Descriptor The event package descriptor provides correspondence between an event representing a program and a package. The event package descriptor may be placed in the MH-EIT transmitted in the M2 section message.

(3) Background Color Specification Descriptor The background color specification descriptor provides the background color of the backmost element in the layout specification. The background color specification descriptor may be placed in the LCT.

(4) MPU Presentation Area Designation Descriptor The MPU presentation area designation descriptor provides a position for presenting the MPU. The MPU presentation area designation descriptor may be placed in the MPT.

(5) MPU timestamp descriptor The MPU timestamp descriptor indicates the presentation time of the first access unit in presentation order in the MPU. The MPU timestamp descriptor may be placed in the MPT.

(6) Dependency Descriptor The dependency descriptor provides the asset ID of the dependent asset. The dependency descriptor may be placed in the MPT.

(7) Access Control Descriptor The access control descriptor provides information for identifying a conditional access method. The access control descriptor may be placed in the MPT or CAT (MH).

(8) Scrambling Scheme Descriptor The scrambling scheme descriptor provides information for identifying the encryption target and the type of encryption algorithm at the time of scrambling. The scrambling scheme descriptor may be placed in the MPT or CAT (MH).

(9) Message Authentication Scheme Descriptor The message authentication scheme descriptor provides information for identifying a message authentication scheme when performing message authentication. The message authentication scheme descriptor may be placed in the MPT or CAT (MH).

(10) Emergency Information Descriptor (MH)
The emergency information descriptor (MH) is used when an emergency alert is broadcast. The emergency information descriptor (MH) may be placed in the MPT.

(11) MH-MPEG-4 Audio Descriptor The MH-MPEG-4 Audio Descriptor is used to describe basic information for specifying the coding parameters of an audio stream of ISO/IEC 14496-3 (MPEG-4 Audio). The MH-MPEG-4 Audio Descriptor may be placed in the MPT.

(12) MH-MPEG-4 Audio Extension Descriptor The MH-MPEG-4 Audio Extension Descriptor is used to describe the profile and level of an MPEG-4 audio stream and the coding method specific settings. The MH-MPEG-4 Audio Extension Descriptor may be placed in the MPT.

(13) MH-HEVC Video Descriptor The MH-HEVC video descriptor is used to describe basic coding parameters of a video stream (HEVC stream) of ITU-T Recommendation H.265|ISO/IEC 23008-2. The MH-HEVC video descriptor may be placed in the MPT.

(14) MH-Link Descriptor The MH-Link Descriptor identifies the service that will be provided if a viewer requests additional information related to a particular listing in the program service information system. The MH-Link Descriptor may be located in the MPT, MH-EIT, MH-SDT, etc.

(15) MH-Event Group Descriptor The MH-Event Group Descriptor is used to indicate that multiple events are grouped when there is a relationship between the events. The MH-Event Group Descriptor may be placed in the MH-EIT.

(16) MH-Service List Descriptor The MH-Service List Descriptor provides a list of services by service identification and service type. The MH-Service List Descriptor may be located in the MH-BIT.

(17) MH-Short Event Descriptor The MH-Short Event Descriptor represents an event name and a short description of the event in text form. The MH-Short Event Descriptor may be placed in the MH-EIT.

(18) MH-Extended Event Descriptor The MH-Extended Event Descriptor is used in addition to the MH-Short Event Descriptor to provide a detailed description of an event. The MH-Extended Event Descriptor may be placed in the MH-EIT.

(19) Video Component Descriptor The video component descriptor indicates parameters and descriptions related to a video component, and is also used to express an elementary stream in a character format. The video component descriptor may be placed in the MPT or MH-EIT.

(20) MH-Stream Identification Descriptor The MH-Stream Identification Descriptor is used to label a component stream of a service and to refer to the description contents indicated by the video component descriptor in the MH-EIT by this label. The MH-Stream Identification Descriptor may be placed in the MPT.

(21) MH-Content Descriptor The MH-Content Descriptor indicates the genre of an event. The MH-Content Descriptor may be placed in the MH-EIT.

(22) MH-Parental Rating Descriptor The MH-Parental Rating Descriptor is used to indicate viewing restrictions based on age and to extend to other restriction conditions. The MH-Parental Rating Descriptor may be placed in the MPT or MH-EIT.

(23) MH-Audio Component Descriptor The MH-Audio Component Descriptor indicates each parameter of an audio elementary stream and is also used to express the elementary stream in a character format. The MH-Audio Component Descriptor may be placed in the MPT or the MH-EIT.

(24) MH-Target Region Descriptor The MH-Target Region Descriptor is used to describe the region targeted by a program or some of the streams that constitute a program. The MH-Target Region Descriptor may be placed in the MPT.

(25) MH-Series Descriptor The MH-Series Descriptor is used to identify a series of programs. The MH-Series Descriptor may be placed in the MH-EIT.

(26) MH-SI Transmission Parameter Descriptor The MH-SI transmission parameter descriptor is used to indicate the transmission parameters of the SI. The MH-SI transmission parameter descriptor may be located in the MH-BIT.

(27) MH-Broadcaster Name Descriptor The MH-Broadcaster Name Descriptor describes the name of a broadcaster. The MH-Broadcaster Name Descriptor may be placed in the MH-BIT.

(28) MH-Service Descriptor The MH-Service Descriptor represents the name of a channel and its operator together with the service type in character codes. The MH-Service Descriptor may be placed in the MH-SDT.

(29) IP Data Flow Descriptor The IP Data Flow Descriptor provides information about the IP data flows that constitute a service. The IP Data Flow Descriptor may be located in the MH-SDT.

(30) MH-CA Invocation Descriptor The MH-CA invocation descriptor describes invocation information for invoking a CAS program on the CAS platform. The MH-CA invocation descriptor may be located in the MPT or CAT (CA).

(31) MH-Type Descriptor The MH-Type descriptor indicates the type of file transmitted in the application transmission method. The MH-Type descriptor may be placed in the DAM table.

(32) MH-Info Descriptor The MH-Info Descriptor describes information about an MPU or an item. The MH-Info Descriptor may be placed in a DAM table.

(33) MH-Expire Descriptor The MH-Expire descriptor describes the expiration date of an item. The MH-Expire descriptor may be placed in the DAM table.

(34) MH-Compression Type Descriptor The MH-Compression Type Descriptor indicates that the item to be transmitted is compressed, and indicates the compression algorithm and the number of bytes of the item before compression. The MH-Compression Type Descriptor may be placed in the DAM table.

(35) MH-Data Coding Scheme Descriptor The MH-Data Coding Scheme Descriptor is used to identify a data coding scheme. The MH-Data Coding Scheme Descriptor may be placed in the MPT.

(36) UTC-NPT Reference Descriptor The UTC-NPT reference descriptor is used to convey the relationship between the NPT (Normal Play Time) and the UTC. The UTC-NPT reference descriptor may be placed in the EMT.

(37) Event Message Descriptor The event message descriptor conveys information about event messages in general. The event message descriptor may be placed in the EMT.

(38) MH-Local Time Offset Descriptor The MH-Local Time Offset Descriptor is used when a certain offset value is to be given between the actual time (e.g., UTC+9 hours) and the display time in the human system during daylight saving time. The MH-Local Time Offset Descriptor may be placed in the MH-TOT.

(39) MH-Component Group Descriptor The MH-Component Group Descriptor defines and identifies a combination of components in an event. The MH-Component Group Descriptor may be placed in the MH-EIT.

(40) MH-Logo Transmission Descriptor The MH-Logo Transmission Descriptor is used to describe a character string for a simple logo, pointing to a logo in CDT format, etc. The MH-Logo Transmission Descriptor may be placed in the MH-SDT.

(41) MPU Extended Timestamp Descriptor The MPU extended timestamp descriptor provides the decoding time of an access unit in an MPU. The MPU extended timestamp descriptor may be placed in the MPT.

(42) MPU Download Content Descriptor The MPU download content descriptor is used to describe attribute information of content downloaded using the MPU. The MPU download content descriptor may be placed in the MH-SDTT.

(43) MH-Network Download Content Descriptor The MH-Network Download Content Descriptor is used to describe attribute information of content downloaded using a network. The MH-Network Download Content Descriptor may be placed in the MH-SDTT.

(44) MH-Application Descriptor The MH-Application Descriptor describes information about an application. The MH-Application Descriptor may be placed in the MH-AIT.

(45) MH-Transmission Protocol Descriptor The MH-Transmission Protocol Descriptor is used to specify a transmission protocol such as broadcasting or communication, and to indicate location information of an application depending on the transmission protocol. The MH-Transmission Protocol Descriptor may be placed in the MH-AIT.

(46) MH-simple application location descriptor The MH-simple application location descriptor is described to indicate details of the acquisition location of an application. The MH-simple application location descriptor may be placed in the MH-AIT.

(47) MH-Application Boundary Authority Setting Descriptor The MH-application boundary authority setting descriptor is described to set an application boundary and to set authority of broadcast resource access for each area (URL). The MH-application boundary authority setting descriptor may be placed in the MH-AIT.

(48) MH-Launching Priority Information Descriptor The MH-Launching Priority Information Descriptor is described to specify the startup priority of an application. The MH-Launching Priority Information Descriptor may be placed in the MH-AIT.

(49) MH-cache information descriptor The MH-cache information descriptor is described for use in cache control when the resources constituting an application are cached and held when the application is expected to be reused. The MH-cache information descriptor may be placed in the MH-AIT.

(50) MH-Probabilistic Application Delay Descriptor The MH-Probabilistic Application Delay Descriptor is used to delay the timing of application control by a probabilistically set delay amount, assuming load balancing of server access for application acquisition. The MH-Probabilistic Application Delay Descriptor may be placed in the MH-AIT.

(51) Link Destination PU Descriptor The link destination PU descriptor describes another presentation unit that may transition from the presentation unit (PU). The link destination PU descriptor may be placed in the DCC table.

(52) Lock Cache Designation Descriptor The lock cache designation descriptor describes the designation of a file to be cached and locked in the presentation unit. The lock cache designation descriptor may be arranged in the DCC table.

(53) Unlock Cache Designation Descriptor The unlock cache designation descriptor describes the designation of a file to be unlocked among the files locked in the presentation unit. The unlock cache designation descriptor may be arranged in the DCC table.

(54) MH-Download Protection Descriptor The MH-Download Protection Descriptor describes location information and transmission information of an MMTP packet that transmits a DCM or DMM. The MH-Download Protection Descriptor may be placed in the MPT or MH-SDTT.

(55) Application Service Descriptor The application service descriptor describes entry information of an application related to a service, etc. The application service descriptor may be placed in the MPT.

(56) MPU Node Descriptor The MPU node descriptor indicates that the MPU corresponds to a directory node defined in the data directory management table. The MPU node descriptor may be placed in the DAM table.

(57) PU Configuration Descriptor The PU configuration descriptor indicates a list of MPUs that constitute a presentation unit as mapping information between the presentation unit and a transmission unit. The PU configuration descriptor may be arranged in the DCC table.

(58) MH-Hierarchical Coding Descriptor The MH-Hierarchical Coding Descriptor describes information for identifying a hierarchically coded video stream component. The MH-Hierarchical Coding Descriptor may be placed in the MPT.

(59) Content Copy Control Descriptor The content copy control descriptor indicates information for controlling the copy generation in a digital recording device for the entire service, and is used by a broadcasting station (copyright holder) to convey information about copying or the maximum transmission rate to a digital recording device when digital recording is assumed to be performed. The content copy control descriptor may be placed in the MPT, MH-EIT, MH-SDT, etc.

(60) Content Usage Control Descriptor The content usage control descriptor is used to indicate information on copy control and remote viewing control for a program when storing the program on a hard disk or the like or when outputting video/audio signals from a receiver. The content usage control descriptor may be placed in the MPT, MH-EIT, MH-SDT, etc.

(61) Descriptors Set by Service Providers In addition, service providers and the like may prepare their own unique descriptors.

<Relationship between data transmission and each control information in the MMT system>
Here, the relationship between each component such as video and audio transmitted by the broadcast system supported by the broadcast receiving device 100 of this embodiment and a representative table of MMT-SI will be described with reference to Fig. 7A. In the MMT method, a component is defined as an asset, and hereinafter, a component may be referred to as an asset.

In the broadcasting system supported by the broadcast receiving device 100 of this embodiment, data can be transmitted via multiple routes, such as a TLV stream via a broadcast transmission path and an IP data flow via a communication line. The TLV stream includes TLV-SI such as TLV-NIT and AMT, and an IP data flow, which is a data flow of IP packets. The IP data flow includes video assets including a series of video MPUs and audio assets including a series of audio MPUs. Similarly, the IP data flow may include subtitle assets including a series of subtitle MPUs, character superimposition assets including a series of character superimposition MPUs, data assets including a series of data MPUs, etc.

These various assets are associated with a "package" by the description in the MPT (MMT package table) stored in the PA message and transmitted. Specifically, the association can be achieved by describing in the MPT a package ID that identifies the package and an asset ID that identifies each asset included in the package. Figure 7B shows an example of the data structure of the MPT. The "MMT_package_id_byte" parameter in the figure corresponds to the package ID, and the "asset_id_byte" parameter corresponds to the asset ID.

The assets constituting a package can consist of only assets in a TLV stream, but as shown in FIG. 7A, they can also include assets transmitted in an IP data flow on a communication line. This can be achieved by describing the location information of each asset contained in the package together with an asset ID that identifies the asset in the MPT, enabling the broadcast receiving device 100 of this embodiment to grasp the reference destination of each asset. The location information is specified by "MMT_general_location_info()" in the data structure of the MPT shown in FIG. 7B. An example of the data structure of location information is shown in FIG. 7C.

Depending on the value of the "location_type" parameter of the location information,
(1) Data multiplexed in the same IP data flow as MPT (location_type = 0x00)
(2) Data multiplexed in IPv4 data flow (location_type = 0x01)
(3) Data multiplexed in IPv6 data flow (location_type = 0x02)
(4) Data multiplexed in the broadcast MPEG2-TS (location_type = 0x03)
(5) Data multiplexed in the IP data flow in MPEG2-TS format (location_type = 0x04)
(6) Data at the specified URL (location_type = 0x05)
It is possible to configure the broadcast receiving device 100 so that it can refer to various types of data transmitted via various transmission paths such as the above.

Among the above-mentioned references, (1) is, for example, an IP data flow included in the TLV stream of the digital broadcast signal received by the broadcast receiving device 100 of this embodiment via the antenna 100a. However, when the MPT is also included in the IP data flow on the communication line side and transmitted, the reference of (1) may be the IP data flow received via the communication line. Also, (2), (3), (5), and (6) are IP data flows received by the broadcast receiving device 100 of this embodiment via the communication line. Also, (4) can be used, for example, in the case of a broadcast receiving device having both a receiving function for receiving digital broadcast signals using the MMT method and a receiving function for receiving digital broadcast signals using the MPEG2-TS method, such as the broadcast receiving device 800 of the second embodiment described later, when referring to data multiplexed in the MPEG2-TS received by the receiving function for receiving digital broadcast signals using the MPEG2-TS method based on the location information of the MPT included in the digital broadcast signal using the MMT method.

In addition, in media such as video components and audio components, the presentation time and decode time can be specified on an MPU or access unit basis. Information on the presentation time and decode time is described in the MPT as an MPU timestamp descriptor or an MPU extended timestamp descriptor. FIG. 7D shows an example of the data structure of an MPU timestamp descriptor that describes information on the presentation time. The presentation time information of each MPU is specified by the "mpu_presentation_time" parameter of the MPU timestamp descriptor. The MPU to be specified can be identified by the "mpu_sequence_number" parameter. In the broadcast receiving device 100 of this embodiment, the presentation time information is used to present (display, output, etc.) multiple MPUs specified by the MPT in conjunction with each other based on a clock based on the NTP, which is time information in UTC notation. Information on the decode time is also described by an MPU extended timestamp descriptor, but detailed description will be omitted. The presentation control of various data using the clock based on the NTP will be described later.

In the broadcasting system of this embodiment, the series of data in "package" units corresponds to a "service" of digital broadcasting. Furthermore, the "service" is a series of "programs" transmitted according to a schedule. In the MMT method, the "programs" are treated as "events". The start time and duration of each event are specified by the MH-EIT. Furthermore, the ID of the MMT package to which each event corresponds is specified by the event package descriptor placed in the MH-EIT. An example of the data structure of the MH-EIT is shown in Figure 7E. The start time is specified by the "start_time" parameter in the figure, and the duration is specified by the "duration" parameter. An example of the data structure of the event package descriptor is shown in Figure 7F. The correspondence between each event and an MMT package can be specified by the "MMT_package_id_byte" parameter of the event package descriptor placed in the MH-EIT. The MH-EIT can be used in the broadcast receiving device 100 of this embodiment for various processes on an "event" basis (for example, the generation of an electronic program guide, control of recording and viewing reservations, copyright management processes such as temporary storage, etc.).

[Hardware configuration of broadcast receiving device]
8A is a block diagram showing an example of the internal configuration of the broadcast receiving device 100. The broadcast receiving device 100 is composed of a main control unit 101, a system bus 102, a ROM 103, a RAM 104, a storage (accumulation) unit 110, a LAN communication unit 121, an extension interface unit 124, a digital interface unit 125, a tuner/demodulation unit 131, a separation unit 132, a video decoder 141, a video color gamut conversion unit 142, an audio decoder 143, a text superimposition decoder 144, a subtitle decoder 145, a subtitle synthesis unit 146, a subtitle color gamut conversion unit 147, a data decoder 151, a cache unit 152, an application control unit 153, a browser unit 154, an application color gamut conversion unit 155, a sound source unit 156, a video synthesis unit 161, a monitor unit 162, a video output unit 163, an audio synthesis unit 164, a speaker unit 165, an audio output unit 166, and an operation input unit 170.

The main control unit 101 is a microprocessor unit that controls the entire broadcast receiving device 100 according to a predetermined operating program. The system bus 102 is a data communication path for transmitting and receiving data between the main control unit 101 and each operating block within the broadcast receiving device 100.

ROM (Read Only Memory) 103 is a non-volatile memory that stores basic operation programs such as an operating system and other operation programs, and may be a rewritable ROM such as an EEPROM (Electrically Erasable Programmable ROM) or a flash ROM. Operation setting values required for the operation of the broadcast receiving device 100 may be stored in ROM 103. RAM (Random Access Memory) 104 serves as a work area when the basic operation programs and other operation programs are executed. ROM 103 and RAM 104 may be integrated with the main control unit 101. ROM 103 may not be an independent configuration as shown in FIG. 8A, but may use a portion of the storage area in the storage unit 110.

The storage (accumulation) unit 110 stores the operation program and operation setting values of the broadcast receiving device 100, personal information of the user of the broadcast receiving device 100, etc. It can also store operation programs downloaded via the Internet 200 and various data created by the operation programs. It can also store content such as video, still images, and audio acquired from broadcast waves or downloaded via the Internet 200. A portion of the storage (accumulation) unit 110 may replace all or part of the functions of the ROM 103. The storage (accumulation) unit 110 must retain the stored information even when power is not being supplied from an external source to the broadcast receiving device 100. Therefore, for example, devices such as non-volatile semiconductor element memories such as flash ROM and SSD (Solid State Drive), and magnetic disk drives such as HDD (Hard Disc Drive) are used.

The operating programs stored in the ROM 103 and the storage unit 110 can be added to, updated, and have their functions expanded by downloading from each server device on the Internet 200.

The LAN (Local Area Network) communication unit 121 is connected to the Internet 200 via the router device 200r, and transmits and receives data to and from each server device and other communication devices on the Internet 200. It also acquires the MMT data string (or a part of it) of a program transmitted via a communication line. The connection to the router device 200r may be a wired connection or a wireless connection such as Wi-Fi (registered trademark). The LAN communication unit 121 includes an encoding circuit, a decoding circuit, and the like. The broadcast receiving device 100 may further include other communication units such as a BlueTooth (registered trademark) communication unit, an NFC communication unit, an infrared communication unit, and the like.

The tuner/demodulator 131 receives broadcast waves transmitted from the radio tower 300t via the antenna 100a, and tunes (selects) the channel of the service desired by the user under the control of the main controller 101. Furthermore, the tuner/demodulator 131 demodulates the received broadcast signal to obtain an MMT data string. Note that while the example shown in FIG. 8A illustrates a configuration with one tuner/demodulator, the broadcast receiving device 100 may be configured to include multiple tuner/demodulators for purposes such as simultaneous display of multiple screens and recording of other programs.

The separation unit 132 is an MMT decoder, and distributes the real-time presentation elements such as a video data string, an audio data string, a text superimposed data string, and a subtitle data string to the video decoder 141, the audio decoder 143, the text superimposed data string, and the subtitle decoder 145, based on the control signal in the input MMT data string. The data input to the separation unit 132 may be an MMT data string transmitted via a broadcast transmission path and demodulated by the tuner/demodulation unit 131, or an MMT data string transmitted via a communication line and received by the LAN communication unit 121. The separation unit 132 also plays back a multimedia application and file-based data that is a component of the application, and temporarily stores the data in the cache unit 152. The separation unit 132 also extracts generic data and outputs it to the data decoder 151 for use in streaming data for a player that presents data other than video, audio, and subtitles, or data for an application. In addition, the separation unit 132 may perform error correction and access restriction control on the input MMT data sequence based on the control of the main control unit 101.

The video decoder 141 decodes the video data string input from the separation unit 132 and outputs video information. The video color gamut conversion unit 142 performs color space conversion processing on the video information decoded by the video decoder 141 as necessary for video synthesis processing in the video synthesis unit 161. The audio decoder 143 decodes the audio data string input from the separation unit 132 and outputs the audio information. In addition, the video decoder 141 and the audio decoder 143 may be input with streaming data in, for example, MPEG-DASH (MPEG-Dynamic Adaptive Streaming over HTTP) format acquired from the Internet 200 via the LAN communication unit 121. In addition, a plurality of video decoders 141, video color gamut conversion units 142, audio decoders 143, etc. may be provided in order to simultaneously decode and process a plurality of types of video data strings and audio data strings.

The character superimposition decoder 144 decodes the character superimposition data string input from the separation unit 132 and outputs character superimposition information. The subtitle decoder 145 decodes the subtitle data string input from the separation unit 132 and outputs subtitle information. The character superimposition information output from the character superimposition decoder 144 and the subtitle information output from the subtitle decoder 145 are subjected to synthesis processing in the subtitle synthesis unit 146, and further, in the subtitle color gamut conversion unit 147, color space conversion processing is performed as necessary for video synthesis processing in the video synthesis unit 161. Note that in this embodiment, among the services centered on text information presented simultaneously with the video of a broadcast program, those related to the content of the video are referred to as subtitles, and the rest are referred to as character superimposition. Furthermore, when there is no distinction between them, they are collectively referred to as subtitles.

The browser unit 154 presents the multimedia application file and its component file data acquired from the server device on the Internet 200 via the cache unit 152 or the LAN communication unit 121 in accordance with the instructions of the application control unit 153, which interprets the control information included in the MMT data string and the control information acquired from the server device on the Internet 200 via the LAN communication unit 121. The multimedia application file may be an HTML (Hyper Text Markup Language) document or a BML (Broadcast Markup Language) document, etc. The application information output from the browser unit 154 is further subjected to color space conversion processing as necessary in the application color gamut conversion unit 155 for video synthesis processing in the video synthesis unit 161. The browser unit 154 also plays application audio information by influencing the sound source unit 156.

The video synthesis unit 161 inputs the video information output from the video color gamut conversion unit 142, the subtitle information output from the subtitle color gamut conversion unit 147, the application information output from the application color gamut conversion unit 155, and the like, and performs processing such as selection and/or superimposition as appropriate. The video synthesis unit 161 is equipped with a video RAM (not shown), and the monitor unit 162 and the like are driven based on the video information input to the video RAM. In addition, based on the control of the main control unit 101, the video synthesis unit 161 performs scaling processing and superimposition processing of EPG (Electronic Program Guide) screen information created based on information such as MH-EIT included in MMT-SI, as necessary. The monitor unit 162 is a display device such as a liquid crystal panel, and provides the video information selected and/or superimposed by the video synthesis unit 161 to the user of the broadcast receiving device 100. The video output unit 163 is a video output interface that outputs the video information that has been selected and/or superimposed by the video synthesis unit 161.

The presentation function of the broadcast receiving device 100 of this embodiment is provided with a logical plane structure in order to display the multimedia service as intended by the provider. FIG. 8B shows an example of the configuration of the logical plane structure provided by the presentation function of the broadcast receiving device 100 of this embodiment. In the logical plane structure, a character superimposition plane for displaying character superimposition is arranged in the foreground, and a subtitle plane for displaying subtitles is arranged in the next layer. A multimedia plane for displaying broadcast video, multimedia applications, or composite video thereof is arranged in the third layer, and a background plane is arranged in the background. The subtitle synthesis unit 146 and the video synthesis unit 161 draw character superimposition information on the character superimposition plane, subtitle information on the subtitle plane, and video information, application information, and the like on the multimedia plane. In addition, a background color is drawn on the background plane based on the LCT, etc. included in the MMT-SI. It is assumed that multiple multimedia planes in the third layer can be prepared according to the number of video decoders 141. However, even if there are multiple multimedia planes, application information, etc. output from the application color gamut conversion unit 155 is output only to the foreground multimedia plane.

The voice synthesis unit 164 inputs the voice information output from the voice decoder 143 and the application voice information reproduced by the sound source unit 156, and performs processing such as selection and/or mixing as appropriate. The speaker unit 165 provides the voice information selected and/or mixed by the voice synthesis unit 164 to the user of the broadcast receiving device 100. The voice output unit 166 is an audio output interface that outputs the voice information selected and/or mixed by the voice synthesis unit 164.

The expansion interface unit 124 is a group of interfaces for expanding the functions of the broadcast receiving device 100, and in this embodiment, is composed of an analog video/audio interface, a USB (Universal Serial Bus) interface, a memory interface, etc. The analog video/audio interface inputs analog video/audio signals from external video/audio output devices, outputs analog video/audio signals to external video/audio input devices, etc. The USB interface connects to a PC or the like to send and receive data. A HDD may be connected to record broadcast programs and content. A keyboard or other USB device may also be connected. The memory interface connects to a memory card or other memory medium to send and receive data.

The digital interface unit 125 is an interface that outputs or inputs encoded digital video data and/or digital audio data. The digital interface unit 125 is capable of directly outputting the MMT data string obtained by demodulation in the tuner/demodulator unit 131, the MMT data string obtained via the LAN communication unit 121, or mixed data of the above-mentioned MMT data strings. In addition, the MMT data string input from the digital interface unit 125 may be controlled to be input to the separation unit 132. The output of digital content stored in the storage unit 110, or the storage of digital content in the storage unit 110 may be performed via the digital interface unit 125.

The digital interface unit 125 may be a DVI terminal, an HDMI (registered trademark) terminal, a Display Port (registered trademark) terminal, etc., and may output or input data in a format conforming to the DVI specification, the HDMI specification, the Display Port specification, etc. It may output or input data in the form of serial data conforming to the IEEE 1394 specification, etc. It may also be configured as an IP interface that performs digital interface output via hardware such as Ethernet (registered trademark) or wireless LAN. In this case, the digital interface unit 125 and the LAN communication unit 121 may share the hardware configuration.

The operation input unit 170 is an instruction input unit that inputs operation instructions to the broadcast receiving device 100, and in this embodiment, is configured with a remote control receiving unit that receives commands transmitted from a remote control (not shown) and an operation key with an array of button switches. Only one of them may be used. The operation input unit 170 may also be replaced by a touch panel placed on top of the monitor unit 162. It may also be replaced by a keyboard or the like connected to the extended interface unit 124. The remote control (not shown) may also be replaced by a mobile information terminal 700 equipped with a remote control command transmission function.

As described above, when the broadcast receiving device 100 is a television receiver or the like, the video output unit 163 and the audio output unit 166 are not essential components of the present invention. In addition, the broadcast receiving device 100 may be a television receiver, an optical disk drive recorder such as a DVD (Digital Versatile Disc) recorder, a magnetic disk drive recorder such as a HDD recorder, a STB (Set Top Box), etc. It may also be a PC (Personal Computer), a tablet terminal, a navigation device, a game console, etc. equipped with a digital broadcast receiving function or a broadcast communication linkage function. When the broadcast receiving device 100 is a DVD recorder, a HDD recorder, a STB, etc., the monitor unit 162 and the speaker unit 165 may not be provided. By connecting an external monitor and external speakers to the video output unit 163 and audio output unit 166 or the digital interface unit 125, it becomes possible to achieve the same operation as the broadcast receiving device 100 of this embodiment.

[Software configuration of broadcast receiving device]
8C is a software configuration diagram of the broadcast receiving device 100 of this embodiment, and shows the software configuration in the ROM 103, the RAM 104, and the storage (accumulation) unit 110. In this embodiment, a basic operation program 1001 and other operation programs are stored in the ROM 103, and a receiving function program 1002, a link function program 1003, a recording and playback function program 1004, and other operation programs are stored in the storage (accumulation) unit 110. The storage (accumulation) unit 110 is also assumed to include a content storage area 1200 for storing content such as moving images, still images, and audio, an authentication information storage area 1300 for storing authentication information and the like required for accessing an external mobile terminal device or each server device, and various information storage areas for storing various other information.

The basic operation program 1001 stored in the ROM 103 is expanded in the RAM 104, and the main control unit 101 executes the expanded basic operation program 1001 to form a basic operation execution unit 1101. Similarly, the reception function program 1002, the linkage function program 1003, and the recording and playback function program 1004 stored in the storage unit 110 are expanded in the RAM 104, and the main control unit 101 executes the expanded reception function program 1002, the linkage function program 1003, and the recording and playback function program 1004 to form the reception function execution unit 1102, the linkage function execution unit 1103, and the recording and playback function execution unit 1104. The RAM 104 also has a temporary storage area that temporarily holds data created when each operation program is executed as necessary.

In the following, for simplicity, the process in which the main control unit 101 controls each operation block by expanding the basic operation program 1001 stored in the ROM 103 into the RAM 104 and executing it will be described as the basic operation execution unit 1101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The receiving function execution unit 1102 controls each operation block of the broadcast receiving device 100 to play components such as video and audio transmitted in the broadcasting system of this embodiment. In particular, the transport processing unit 1102a mainly controls the MMT decoder function of the separation unit 132, and distributes the video data string and audio data string separated from the MMT data string to the corresponding decoding processing units. The AV decoding processing unit 1102b mainly controls the video decoder 141 and audio decoder 143. The application processing unit 1102c mainly controls the cache unit 152, application control unit 153, browser unit 154, and sound source unit 156. The character superimposition processing unit 1102d mainly controls the character superimposition decoder 144. The subtitle processing unit 1102e mainly controls the subtitle decoder 145. The general-purpose data processing unit 1102f mainly controls the data decoder 151. The EPG generation unit 1102g interprets the description contents of the MH-EIT and the like included in the MMT-SI to generate an EPG screen. The presentation processing unit 1102h mainly controls the video color gamut conversion unit 142, the subtitle synthesis unit 146, the subtitle color gamut conversion unit 147, the application color gamut conversion unit 155, the video synthesis unit 161, and the audio synthesis unit 164 based on the logical plane structure.

The linkage function execution unit 1103 also manages device authentication and connection, transmission and reception of data, and the like, when the broadcast receiving device 100 performs linkage operations with an external device such as the mobile information terminal 700. The recording and playback function execution unit 1104 controls the recording of broadcast programs obtained from the digital broadcast waves of this broadcasting system and content obtained from each server device on the network in the content storage area 1200 of the storage unit 110 or in an external storage connected to the expansion interface unit 124, or the playback of the broadcast programs and content.

The operating programs may be stored in the ROM 103 and/or the storage unit 110 beforehand at the time of product shipment. After product shipment, the operating programs may be acquired from other application servers 500 on the Internet 200 via the LAN communication unit 121. In addition, the operating programs stored on a memory card, optical disk, etc. may be acquired via the expansion interface unit 124, etc.

[Configuration of broadcasting station server]
9 is a block diagram showing an example of the internal configuration of the broadcast station server 300. The broadcast station server 300 is made up of a main control unit 301, a system bus 302, a RAM 304, a storage unit 310, a LAN communication unit 321, and a digital broadcast signal transmission unit 360.

The main control unit 301 is a microprocessor unit that controls the entire broadcasting station server 300 in accordance with a predetermined operation program. The system bus 302 is a data communication path for transmitting and receiving data between the main control unit 301 and each operation block within the broadcasting station server 300. The RAM 304 serves as a work area when each operation program is executed.

The storage unit 310 stores a basic operation program 3001, a broadcast content management/distribution program 3002, and a broadcast content transmission program 3003, and further includes a broadcast content storage area 3200 and a metadata storage area 3300. The broadcast content storage area 3200 stores program content, etc., of each broadcast program broadcast by a broadcast station. The metadata storage area 3300 stores metadata, such as the program title, program ID, program summary, cast, broadcast date and time, and copy control information related to each program content, of each broadcast program.

The basic operation program 3001, broadcast content management/distribution program 3002, and broadcast content sending program 3003 stored in the storage unit 310 are each expanded in the RAM 304, and the main control unit 301 executes each of the expanded programs to form a basic operation execution unit 3101, a broadcast content management/distribution execution unit 3102, and a broadcast content sending execution unit 3103.

In the following, for simplicity, the process in which the main control unit 301 controls each operation block by expanding the basic operation program 3001 stored in the storage unit 310 into the RAM 304 and executing it will be described as the basic operation execution unit 3101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The broadcast content management/distribution execution unit 3102 manages the program content and each metadata of each broadcast program stored in the broadcast content storage area 3200 and the metadata storage area 3300, and controls the provision of the program content and each metadata of each broadcast program to the service provider based on a contract. Furthermore, when providing the program content and each metadata of each broadcast program to the service provider, the broadcast content management/distribution execution unit 3102 may perform authentication processing of the service provider server 400 based on the contract as necessary.

The broadcast content transmission execution unit 3103 performs time schedule management when transmitting the program content of the broadcast program stored in the broadcast content storage area 3200 and the MMT data sequence including the program title, program ID, and copy control information of the program content of the broadcast program stored in the metadata storage area 3300 from the radio tower 300t via the digital broadcast signal transmission unit 360.

The LAN communication unit 321 is connected to the Internet 200 and communicates with the service provider server 400 on the Internet 200. The LAN communication unit 321 includes an encoding circuit, a decoding circuit, and the like. The digital broadcast signal sending unit 360 modulates an MMT data sequence consisting of video data sequences, audio data sequences, program information data sequences, and the like, of the program contents of each broadcast program stored in the broadcast content storage area 3200, and sends it out as a digital broadcast wave via the radio tower 300t.

[Configuration of service provider server]
10 is a block diagram showing an example of the internal configuration of the service provider server 400. The service provider server 400 is composed of a main control unit 401, a system bus 402, a RAM 404, a storage unit 410, and a LAN communication unit 421.

The main control unit 401 is a microprocessor unit that controls the entire service provider server 400 in accordance with a predetermined operation program. The system bus 402 is a data communication path for transmitting and receiving data between the main control unit 401 and each operation block within the service provider server 400. The RAM 404 serves as a work area when each operation program is executed.

The storage unit 410 stores a basic operation program 4001, a video content management/distribution program 4002, and an application management/distribution program 4004, and further includes a video content storage area 4200, a metadata storage area 4300, an application storage area 4400, and a user information storage area 4500. The video content storage area 4200 stores the program content of the broadcast program provided by the broadcast station server 300 as video content. It also stores the video content and the like produced by the service provider. The metadata storage area 4300 stores each metadata provided by the broadcast station server 300 and metadata related to the video content produced by the service provider. The application storage area 4400 stores various applications and the like for realizing services linked to the broadcast program to be distributed in response to requests from each television receiver. The user information storage area 4500 stores information (personal information, authentication information, etc.) related to users who are permitted to access the service provider server 400.

The basic operation program 4001, video content management/distribution program 4002, and application management/distribution program 4004 stored in the storage unit 410 are each expanded in the RAM 404, and the main control unit 401 executes the expanded basic operation program, video content management/distribution program, and application management/distribution program to form a basic operation execution unit 4101, a video content management/distribution execution unit 4102, and an application management/distribution execution unit 4104.

In the following, for ease of explanation, the process in which the main control unit 401 expands the basic operation program 4001 stored in the storage unit 410 into the RAM 404 and executes it to control each operation block will be described as the basic operation execution unit 4101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The video content management/distribution execution unit 4102 acquires program contents and metadata of broadcast programs from the broadcast station server 300, manages the video contents and metadata stored in the video content storage area 4200 and the metadata storage area 4300, and controls the distribution of the video contents and metadata to each television receiver. Furthermore, when distributing the video contents and metadata to each television receiver, the video content management/distribution execution unit 4102 may perform authentication processing of each television receiver as necessary. Furthermore, the application management/distribution execution unit 4104 manages each application stored in the application storage area 4400 and controls the distribution of each application in response to a request from each television receiver. Furthermore, when distributing the application to each television receiver, the application management/distribution execution unit 4104 may perform authentication processing of each television receiver as necessary.

The LAN communication unit 421 is connected to the Internet 200, and communicates with the broadcast station server 300 on the Internet 200 and the broadcast receiving device 100 via the router device 200r. The LAN communication unit 421 is equipped with an encoding circuit, a decoding circuit, etc.

[Hardware configuration of mobile information terminal]
11A is a block diagram showing an example of the internal configuration of a portable information terminal 700. The portable information terminal 700 is composed of a main control unit 701, a system bus 702, a ROM 703, a RAM 704, a storage unit 710, a communication processing unit 720, an expansion interface unit 724, an operation unit 730, an image processing unit 740, an audio processing unit 750, and a sensor unit 760.

The main control unit 701 is a microprocessor unit that controls the entire portable information terminal 700 in accordance with a predetermined operating program. The system bus 702 is a data communication path for transmitting and receiving data between the main control unit 701 and each operating block within the portable information terminal 700.

ROM 703 is a memory in which basic operation programs such as an operating system and other operation programs are stored, and may be a rewritable ROM such as an EEPROM or flash ROM. RAM 704 serves as a work area when the basic operation programs and other operation programs are executed. ROM 703 and RAM 704 may be integrated with the main control unit 701. Also, ROM 703 may not be an independent configuration as shown in FIG. 11A, but may use a portion of the memory area in the storage unit 710.

The storage unit 710 stores the operation program and operation setting values of the mobile information terminal 700, personal information of the user of the mobile information terminal 700, etc. It can also store operation programs downloaded via the Internet 200 and various data created by the operation programs. It can also store content such as videos, still images, and audio downloaded via the Internet 200. A portion of the storage unit 710 may replace all or part of the functions of the ROM 703. The storage unit 710 must also retain the stored information even when the mobile information terminal 700 is not receiving power from an external source. Therefore, for example, devices such as non-volatile semiconductor element memories such as flash ROM and SSDs, and magnetic disk drives such as HDDs are used.

The operating programs stored in the ROM 703 and the storage unit 710 can be added to, updated, and have their functions expanded by downloading from each server device on the Internet 200.

The communication processing unit 720 is composed of a LAN communication unit 721, a mobile telephone network communication unit 722, and an NFC communication unit 723. The LAN communication unit 721 is connected to the Internet 200 via the router device 200r and the access point 200a, and transmits and receives data to and from each server device and other communication devices on the Internet 200. The connection to the router device 200r and the access point 200a is assumed to be made via a wireless connection such as Wi-Fi (registered trademark). The mobile telephone network communication unit 722 performs telephone communication (calls) and data transmission and reception through wireless communication with the base station 600b of the mobile telephone communication network. The NFC communication unit 723 performs wireless communication when in close proximity to a corresponding reader/writer. The LAN communication unit 721, the mobile telephone network communication unit 722, and the NFC communication unit 723 are assumed to each include an encoding circuit, a decoding circuit, an antenna, etc. Additionally, the communication processing unit 720 may further include other communication units, such as a BlueTooth (registered trademark) communication unit or an infrared communication unit.

The expansion interface unit 724 is a group of interfaces for expanding the functions of the portable information terminal 700, and in this embodiment, is composed of a video/audio interface, a USB interface, a memory interface, etc. The video/audio interface inputs video signals/audio signals from external video/audio output devices, outputs video signals/audio signals to external video/audio input devices, etc. The USB interface connects to a PC or the like to send and receive data. It may also be used to connect a keyboard or other USB devices. The memory interface connects to a memory card or other memory medium to send and receive data.

The operation unit 730 is an instruction input unit that inputs operation instructions to the mobile information terminal 700, and in this embodiment, is configured with a touch panel 730t arranged on top of the display unit 741 and operation keys 730k arranged with button switches. Only one of them may be used. The mobile information terminal 700 may be operated using a keyboard or the like connected to the extended interface unit 724. The mobile information terminal 700 may be operated using a separate terminal device connected by wired or wireless communication. In other words, the mobile information terminal 700 may be operated from the broadcast receiving device 100. The touch panel function may also be provided in the display unit 741.

The image processing unit 740 is composed of a display unit 741, an image signal processing unit 742, a first image input unit 743, and a second image input unit 744. The display unit 741 is a display device such as a liquid crystal panel, and provides image data processed by the image signal processing unit 742 to the user of the mobile information terminal 700. The image signal processing unit 742 is equipped with a video RAM (not shown), and the display unit 741 is driven based on the image data input to the video RAM. The image signal processing unit 742 also has a function of performing format conversion, superimposition processing of menus and other OSD (On Screen Display) signals, etc. as necessary. The first image input unit 743 and the second image input unit 744 are camera units that input image data of the surroundings or object by converting light input from a lens into an electrical signal using electronic devices such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) sensor.

The audio processing unit 750 is composed of an audio output unit 751, an audio signal processing unit 752, and an audio input unit 753. The audio output unit 751 is a speaker, and provides the audio signal processed by the audio signal processing unit 752 to the user of the mobile information terminal 700. The audio input unit 753 is a microphone, and converts the user's voice, etc. into audio data and inputs it.

The sensor unit 760 is a group of sensors for detecting the state of the mobile information terminal 700, and in this embodiment, is composed of a GPS receiver unit 761, a gyro sensor 762, a geomagnetic sensor 763, an acceleration sensor 764, an illuminance sensor 765, and a proximity sensor 766. These sensors make it possible to detect the position, inclination, direction, and movement of the mobile information terminal 700, as well as the brightness of the surroundings, the proximity of surrounding objects, and the like. The mobile information terminal 700 may also be equipped with other sensors, such as an air pressure sensor.

The portable information terminal 700 may be a mobile phone, a smartphone, a tablet terminal, or the like. It may also be a PDA (Personal Digital Assistant) or a notebook PC. It may also be a digital still camera, a video camera capable of taking videos, a portable game machine, a navigation device, or other portable digital devices.

The example configuration of the mobile information terminal 700 shown in FIG. 11A includes many components that are not essential to this embodiment, such as the sensor unit 760, but the effect of this embodiment is not diminished even if these components are not included in the configuration. In addition, components not shown, such as a digital broadcast receiving function and an electronic money payment function, may be added.

[Software configuration of mobile information terminal]
11B is a software configuration diagram of the portable information terminal 700 of this embodiment, and shows the software configuration in the ROM 703, the RAM 704, and the storage unit 710. In this embodiment, a basic operation program 7001 and other operation programs are stored in the ROM 703, and a linkage control program 7002 and other operation programs are stored in the storage unit 710. The storage unit 710 is also assumed to include a content storage area 7200 for storing content such as moving images, still images, and audio, an authentication information storage area 7300 for storing authentication information and the like required for accessing a television receiver or each server device, and various information storage areas for storing various other information.

The basic operation program 7001 stored in ROM 703 is expanded in RAM 704, and the main control unit 701 executes the expanded basic operation program to form a basic operation execution unit 7101. Similarly, the cooperative control program 7002 stored in the storage unit 710 is expanded in RAM 704, and the main control unit 701 executes the expanded cooperative control program to form a cooperative control execution unit 7102. The RAM 704 also includes a temporary storage area for temporarily holding data created when each operation program is executed, as necessary.

In the following, for simplicity, the process in which the main control unit 701 loads the basic operation program 7001 stored in the ROM 703 into the RAM 704 and executes it to control each operation block will be described as the basic operation execution unit 7101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The linkage control execution unit 7102 manages device authentication and connection, sending and receiving of data, and the like, when the mobile information terminal 700 performs linkage operations with the television receiver. The linkage control execution unit 7102 also includes a browser engine function for executing applications that link with the television receiver.

The operating programs may be stored in the ROM 703 and/or the storage unit 710 beforehand at the time of product shipment. After product shipment, the operating programs may be acquired from other application servers 500 on the Internet 200 via the LAN communication unit 721 or the mobile telephone network communication unit 722. In addition, the operating programs stored in a memory card, optical disk, etc. may be acquired via the expansion interface unit 724, etc.

[Time management of broadcast receiving device]
The broadcast receiving device 100 of this embodiment has two types of time management functions. The first time management function is a time management function based on NTP, and the second time management function is a time management function based on MH-TOT. The two types of time management functions are described below.

<NTP-based time management function>
First, the time management function based on NTP will be described.

Figure 12A is an example of a system configuration for clock synchronization/presentation synchronization in a broadcasting system that the broadcast receiving device 100 of this embodiment supports. In the broadcasting system of this embodiment, UTC is transmitted from the broadcast sending system to the receiver (such as the broadcast receiving device 100 of this embodiment) in a 64-bit NTP timestamp format. In the NTP timestamp format, UTC "seconds or more" are represented by 32 bits, and "less than a second" is represented by 32 bits. However, in reality, it is difficult to reproduce one second with 32-bit accuracy. For this reason, as a system clock for synchronizing a video system or a system clock for operating an NTP format clock, for example, a frequency of "2 to the 24th power" Hz (approximately 16.8 MHz) as shown in the figure may be used. Note that, considering that the system clock in the conventional broadcasting system was 27 MHz and that the hardware configuration of the receiver can be easily constructed, it is desirable to adopt a frequency of a power of 2, such as "2 to the 24th power" to "2 to the 28th power", as the system clock.

When the system clock is set to a power of 2 frequency such as 2 to the 24th power to 2 to the 28th power on the broadcast transmission system or receiver side as described above, the lower 8 to 4 bits in the NTP timestamp format transmitted from the broadcast transmission system to the receiver side, which are not referenced by the PLL (Phase Locked Loop) system for regenerating the system clock or the NTP format clock, may be fixed to 0 or 1. In other words, if the system clock is 2 to the nth power Hz (n=24 in the example of FIG. 12A, and so forth), the lower 32-n bits in the NTP timestamp format may be fixed to 0 or 1. Alternatively, the receiver side may process the lower 32-n bits in the NTP timestamp format to be ignored.

When the broadcast transmission system receives NTP format time information from the outside, it configures a PLL system with a 32+n bit counter using a VCO (Voltage Controlled Oscillator) of 2n Hz, and realizes a transmission system clock that synchronizes with the time information provided from the outside. In addition, the entire signal processing system operates in synchronization with the 2n Hz system clock. Furthermore, the output of the transmission system clock is periodically transmitted to the receiver side via the broadcast transmission path as NTP long format time information. Note that the NTP long format time information transmitted to the receiver side may also have the lower 32-n bits of the 32 bits representing "less than a second" fixed to "0" or "1". In other words, this is because the system clock counter on the broadcast transmission system side is composed of 32+n bits.

On the receiver side, time information in NTP long format is received via the broadcast transmission path, and, just like on the broadcast transmission system side, the receiving system clock is regenerated using a PLL system based on a 2n-power Hz VCO. This makes the receiving system clock synchronized with the broadcast transmission system side. In addition, by operating the receiver's signal processing system in synchronization with the 2n-power Hz system clock, clock synchronization is achieved between the broadcast transmission system side and the receiver side, enabling stable signal reproduction.

The decode time and presentation time for each presentation unit of the video/audio signal are set on the broadcast transmission system side based on the time information in the NTP format. The decode time is specified by an MPU extended timestamp descriptor (not shown) stored in the MPT. The presentation time is specified by an MPU timestamp descriptor (see FIG. 7D) stored in the MPT. The "mpu_sequence_number" parameter in the MPU timestamp descriptor indicates the sequence number of the MPU that describes the timestamp, and the "mpu_presentation_time" parameter indicates the presentation time of the MPU in 64-bit NTP timestamp format. In other words, the receiver can control the presentation (display, output, etc.) timing of each MPU of video/audio signals, subtitles, superimposed characters, etc. by referring to the MPU timestamp descriptor stored in the MPT.

When focusing on the control of the decoding timing and presentation timing for each presentation unit of the aforementioned video/audio signals, etc., synchronization of the video/audio signals can be ensured even with a clock of about 2 to the power of 16 Hz (approximately 65.5 KHz), and in this case, it is not necessary to refer to the lower 16 bits of the NTP timestamp format described in the MPU timestamp descriptor, etc. In other words, if a clock of 2 to the power of m Hz generated by dividing the system clock, etc. is used to control the decoding timing and presentation timing, it is not necessary to refer to the lower 32-m bits of the NTP timestamp format described in the MPU timestamp descriptor, etc. Therefore, the lower 32-m bits of the NTP timestamp format described in the MPU timestamp descriptor, etc. may be fixed to 0 or 1.

<Time management function based on MH-TOT>
An example of the configuration of time information transmitted in the NTP format in the time management function based on the NTP described above is shown in Figure 12B. The "reference_timestamp" parameter and the "transmit_timestamp" parameter in the NTP format are 64-bit NTP long format time data, and the "mpu_presentation_time" parameter in the MPU time stamp descriptor shown in Figure 7D is also 64-bit NTP time stamp format time data. The NTP long format time data and the NTP time stamp format time data are data in which the "seconds or more" of UTC are represented by 32 bits, and "less than a second" is represented by 32 bits. In other words, the NTP format time information can transmit time information up to "less than a second". Furthermore, since the time information in NTP format is expressed in UTC notation, unlike time management in conventional digital broadcasting, as shown in Figure 3, by managing both the data flow transmitted via the broadcast transmission path and the data flow distributed via the communication line using the time information in NTP format, it is possible to easily ensure consistency between the two sets of data.

In contrast, the time information transmitted by MH-TOT is as follows:

Figure 12C shows an example of the data structure of MH-TOT. The broadcast receiving device 100 of this embodiment can obtain the current date and current time from the "JST_time" parameter of the MH-TOT. As shown in Figure 12D, the "JST_time" parameter contains the lower 16 bits of the coded data of the current date based on the Modified Julian Date (MJD) and 24 bits of information that represents Japan Standard Time (JST) as six 4-bit binary-coded decimal (BCD) numbers. The current date can be calculated by performing a predetermined calculation on the 16-bit coded data of the MJD. Additionally, of the six 4-bit binary coded decimal numbers, the first two 4-bit binary coded decimal numbers represent the hour in two decimal digits, the next two 4-bit binary coded decimal numbers represent the minutes in two decimal digits, and the last two 4-bit binary coded decimal numbers represent the seconds in two decimal digits.

In other words, the difference between time management based on the NTP format and time management based on MH-TOT is that the former, NTP format, can transmit time information down to the "second" as mentioned above, whereas the latter, MH-TOT format, can only transmit time information down to the "second" in JST notation.

The broadcast receiving device 100 of this embodiment can achieve more accurate synchronization processing by using a time management function based on NTP, which is time information in UTC notation, to synchronize the decoding and display of the video, audio, subtitles, superimposed text, and other presented data that are the content of the broadcast signal. Furthermore, by referring to information in UTC notation rather than the clock notation of the broadcast station, it is also possible to perform synchronization processing for the decoding and display of the video, audio, subtitles, superimposed text, or other data that are the content received by the broadcast signal and the video, audio, subtitles, superimposed text, or other data obtained via the communication line path.

Furthermore, in the broadcast receiving device 100 of this embodiment, the time management function based on "JST_time" including 24-bit information expressed in six 4-bit binary-coded decimal numbers of MH-TOT may be used in the process of presenting the current time to the user or each process handling MH-EIT shown in FIG. 7E. Generally, in the process of presenting the current time to the user in a broadcast receiving device, accuracy to the nearest second is rarely required. Also, each piece of time information described in MH-EIT is stored as 24-bit information expressed in six 4-bit binary-coded decimal numbers, with two decimal digits each for "hours," "minutes," and "seconds," as in the EIT of conventional digital broadcasts transmitted by the MPEG2-TS method. For this reason, the time management function based on MH-TOT in the broadcast receiving device 100 of this embodiment is easily compatible with each process handling MH-EIT. Specifically, the processes that handle MH-EIT include, for example, the generation of an electronic program guide, control of recording and viewing reservations, copyright management processes such as temporary storage, etc. It is rare for any of these processes to require accuracy down to the second, and an accuracy of one second is sufficient.

The generation process of the electronic program guide, the control of recording and viewing reservations, copyright management processes such as temporary storage, and the like are also functions that are installed in receivers of digital broadcasting systems using the conventional MPEG2-TS format. In this case, if the broadcasting system of this embodiment is configured so that the generation process of the electronic program guide, the control of recording and viewing reservations, copyright management processes such as temporary storage, and other processes can be handled using time management processes that are consistent with conventional MPEG2-TS digital broadcasting systems, then when configuring a broadcast receiving device that has both the reception function for conventional MPEG2-TS digital broadcasting and the reception function for MMT digital broadcasting, it will no longer be necessary to design separate processing algorithms for these processes (the generation process of the electronic program guide, the control of recording and viewing reservations, copyright management processes such as temporary storage, and other processes), and costs can be reduced.

In addition, even if a receiver does not have the ability to receive digital broadcasts using the conventional MPEG2-TS format, and only has the ability to receive digital broadcasts using the MMT format, it is not necessary to create completely new algorithms for processes such as generating an electronic program guide, controlling recording and viewing reservations, and copyright management processes such as temporary storage. Instead, algorithms for functions that are also installed in receivers for digital broadcast systems using the conventional MPEG2-TS format can be used, allowing development to be carried out at lower cost.

Therefore, by configuring the time management function based on the MH-TOT "JST_time" parameter for these processes (processing such as generating an electronic program guide, controlling recording and viewing reservations, and copyright management processing such as temporary storage), it will be possible to provide MMT-type digital broadcast receiving devices at a lower cost by improving compatibility with conventional broadcasting systems.

As described above, the broadcast receiving device 100 of this embodiment has a time management function that uses two types of time information with different accuracy. That is, the first time information is time information written in a format that is consistent with conventional digital broadcasting systems, and the second time information is time information with a higher resolution than the first time information. By using the second time information for synchronization processing of each content data of the broadcast signal, it is possible to realize information presentation processing that is more advanced than conventional broadcasting systems, and by using the first time information for generation processing of an electronic program guide, control of recording and viewing reservations, copyright management processing such as temporary storage, etc., it is possible to provide a broadcast receiving device at a low cost.

Therefore, by providing the two types of time management functions described above, the broadcast receiving device 100 of this embodiment can achieve both more advanced information presentation processing and lower costs.

[First modified example of time management]
Next, a first modified example of time management in the broadcasting system of this embodiment will be described below.

In a first variant, in order to improve the accuracy of the management time of the NTP-based time management function already described with reference to FIG. 12A, information regarding an estimated delay time in the transmission of time information from a time management server (not shown) or broadcast station server 300 to the broadcast receiving device 100 may be included in the broadcast signal and transmitted, and the broadcast receiving device 100 may be configured to use the information regarding the estimated delay time to correct the system clock of the NTP-based time management function.

In this case, the information on the expected delay time may be configured to be transmitted not in the TLV multiplexed stream of the protocol stack in the broadcast transmission path shown in FIG. 3(A) but in a TMCC (Transmission and Multiplexing Configuration Control) area outside the TLV multiplexed stream. If the information is transmitted in the TMCC area, the broadcast receiving device 100 can extract the information on the expected delay time without undergoing a separation process (demux process) of the TLV multiplexed stream. In other words, it is possible to obtain information that is less susceptible to the delay caused by the separation process in the broadcast receiving device 100, and therefore it is possible to perform a highly accurate system clock correction process. An example of the data structure of the time information transmitted by the TMCC signal is described with reference to FIG. 12E. The time information may be stored in the TMCC extension information area and transmitted, for example. In the time information in the TMCC extended information area shown in the figure, the "delta" parameter represents the expected value of the transmission delay from the time management server that distributes UTC or the server device that creates the TMCC signal to a general broadcast receiving device, using a 32-bit signed fixed point. The upper 16 bits describe the integer part, and the lower 16 bits describe the decimal part. The "transmit_timestamp" parameter is a transmission timestamp, and describes the time when this TMCC signal is sent from the server device in NTP timestamp length format. The upper 32 bits represent the integer part, and the lower 32 bits represent the decimal part.

In the first modified example, the broadcast receiving device 100 of this embodiment can use information about the expected delay time described in the time information stored in the TMCC extended information area and transmitted (e.g., the aforementioned "delta" parameter and/or "transmit_timestamp" parameter) to more accurately correct the system clock of the NTP-based time management function used for synchronizing each content data of the broadcast signal.

[Second modified example of time management]
Next, a second modified example of time management in the broadcasting system of this embodiment will be described below.

As mentioned above, the broadcast receiving device 100 of this embodiment has a time management function that acquires the current date and Japan Standard Time from information transmitted by MH-TOT and manages the time. The current date and Japan Standard Time acquired from information transmitted by MH-TOT can be superimposed on video information, application information, etc. by the video synthesis unit 161 of the broadcast receiving device 100, and output to the monitor unit 162 or video output unit 163 for provision to the user. As mentioned above, MH-TOT has the data structure shown in Figure 12C, and the broadcast receiving device 100 can acquire the current date and current time from the "JST_time" parameter of the MH-TOT.

However, the aforementioned "JST_time" parameter only uses the lowest 16 bits of the MJD encoded data, so an overflow occurs at "April 22, 2038", and dates after "April 23, 2038" cannot be expressed using the specified calculation alone. Therefore, in the second variant of this embodiment, the calculation method is switched between when the MJD value is equal to or greater than a specified value and when it is less than a specified value, so that dates after "April 23, 2038" can be expressed.

Figure 12F shows an example of a first calculation method used when the value of MJD is equal to or greater than a predetermined value, and a second calculation method used when the value of MJD is less than the predetermined value. For example, if the predetermined value is "32768 (0x8000)", the first calculation method is used to calculate the current date when MJD is equal to or greater than "32768", and the second calculation method is used to calculate the current date when MJD is less than "32768". Note that the case where MJD is less than "32768" is equivalent to the case where the most significant bit of the 16-bit data of MJD is "0". This makes it possible for the broadcast receiving device 100 of this embodiment to express dates after "April 23, 2038". However, the predetermined value can be set arbitrarily, and the predetermined value may be set to "16384 (0x4000)" or "49152 (0xC000)", etc. The condition for switching the calculation method may be when the most significant 2 bits of the 16-bit data of the MJD are "00" or when the most significant 2 bits of the 16-bit data of the MJD are not "11." If the above-mentioned means are used with the predetermined value set to "32768," it will not be possible to express dates prior to "September 4, 1948," but this will not be a problem in practical use as a television receiver.

In addition, instead of switching between the first and second calculation methods depending on the comparison result between the MJD and the predetermined value, the first and second calculation methods may be switched depending on a flag that replaces part or all of the "reserved" parameter in the data structure of the MH-TOT shown in FIG. 12C or a newly added flag. For example, when the most significant bit of the 16-bit encoded data of the MJD is "0", the flag may be set to "1" if the MJD indicates "April 23, 2038" or later, and set to "0" if the MJD does not indicate "April 23, 2038" or later. Then, when the flag is "1", the second calculation method shown in FIG. 12F may be used, and when the flag is "0", the first calculation method may be used. Alternatively, a new descriptor having the same meaning as the flag may be prepared and placed in the MH-TOT.

As described above, the broadcasting system of this embodiment transmits absolute time in NTP format, and the broadcasting receiving device 100 of this embodiment has a time management function based on this NTP. Furthermore, the broadcasting receiving device 100 of this embodiment controls the decoding timing and presentation timing for each presentation unit of the video/audio signal by referring to the NTP timestamp etc. described in the MPU timestamp descriptor set on an MPU basis. As described above, the time information in the NTP format has the structure shown in FIG. 12B. Furthermore, the MPU timestamp descriptor has the structure shown in FIG. 7D.

Therefore, in the broadcast receiving device 100 of this embodiment, the "reference_timestamp" parameter, the "transmit_timestamp" parameter, or the "mpu_presentation_time" parameter, etc. may be referenced, and either the first calculation method or the second calculation method may be selected depending on the value of the referenced time data, etc. In other words, for example, if the most significant bit of the 64-bit NTP-length format time data is "0", the second calculation method may be used, and if it is not "0", the first calculation method may be used, etc.

Either way, the broadcast receiving device 100 of this embodiment can express dates after April 23, 2038.

[Broadcast receiving device channel selection process (initial scan)]
The AMT of the broadcasting system of this embodiment provides a list of multicast groups of IP packets so that IP packets transmitted by the TLV multiplexing method can be received without distinction from IP packets transmitted over a communication line as much as possible. Multiple IP multicast groups can be listed for one service identification. Also, an address mask can be used to efficiently describe consecutive IP addresses.

In the broadcast receiving device 100 of this embodiment, when scanning channels for initial settings or when rescanning to change settings, it is possible to store a list of services acquired from the TLV-NIT in non-volatile memory such as the ROM 103 or the storage unit 110, and further, it is possible to store a list of IP multicast groups corresponding to each of the services as IP-related information in the non-volatile memory in association with each of the services. By storing the list of services and the IP-related information in non-volatile memory and making it possible to refer to them at any time, it becomes unnecessary to re-acquire the TLV-NIT or AMT when switching channels, etc., and it becomes possible to acquire broadcast content efficiently.

Figure 13A shows an example of an operational sequence during channel scanning (rescanning) in the broadcast receiving device 100 of this embodiment.

When channel scanning begins, the reception function execution unit 1102 sets an initial frequency value to the tuner/demodulator unit 131 and instructs it to tune to that frequency value (S101). If the tuner/demodulator unit 131 successfully locks onto the set frequency value (S102: Yes), the reception function execution unit 1102 then acquires the TLV-NIT from the received signal (S103).

If the TLV-NIT acquired in the process of S103 is valid data (S104: Yes), the reception function execution unit 1102 acquires information such as the TLV stream ID and original network ID from the acquired TLV-NIT (S105). An example of the data structure of the TLV-NIT is shown in FIG. 13B. The TLV stream ID information can be acquired from the "tlv_stream_id" parameter, and the original network ID information can be acquired from the "original_network_id" parameter. Furthermore, distribution system information related to the physical conditions of the broadcast transmission path corresponding to each TLV stream ID/original network ID is acquired from the distribution system descriptor (S106), and a list of service IDs is acquired from the service list descriptor (S107).

Figure 13C shows an example of the data structure of a satellite distribution system descriptor. Figure 13D shows an example of the data structure of a service list descriptor. If the TLV-NIT has multiple different pieces of data, such as a TLV stream ID, an original network ID, distribution system information, and a list of service IDs, the processes of S105 to S107 are repeated. Next, the reception function execution unit 1102 creates a service list based on the data, such as the TLV stream ID, original network ID, distribution system information, and list of service IDs, acquired in the processes of S105 to S107, and stores the created service list in the ROM 103 or storage unit 110, etc. (updates when rescanning) (S108).

Next, the reception function execution unit 1102 acquires the AMT from the received signal (S109), and further acquires a list of IP multicast groups related to each service ID stored in the service list (S110). FIG. 13E shows an example of the data structure of the AMT. If the AMT has a list of IP multicast groups related to multiple service IDs, the process of S110 is repeated. If there are multiple AMTs that have lists of IP multicast groups related to different service IDs, the processes of S109 to S110 are repeated. Next, the reception function execution unit 1102 associates the list of IP multicast groups acquired in the process of S110 with the service ID as IP-related information, and stores it in the ROM 103 or the storage unit 110, etc. (updates it when rescanning) (S111).

Note that if the tuner/demodulator unit 131 does not succeed in locking onto the set frequency value in the process of S102 (S102: No), and if the TLV-NIT acquired in the process of S103 is not valid data (S104: No), the processes of S105 to S111 are not performed.

After completing the process of S111, if the frequency value set in the tuner/demodulator 131 is the final frequency value of the channel scan range (S112: Yes), the reception function execution unit 1102 ends the process. On the other hand, if the set frequency value is not the final frequency value of the channel scan range (S112: No), the frequency value set in the tuner/demodulator 131 is increased (S113) and the processes of S102 to S111 are repeated. Note that if a single TLV-NIT can acquire service IDs for all services that make up the broadcast network, and if an AMT having a list of IP multicast groups related to the service IDs can be acquired, the processes of S112 to S113 are not necessary.

By performing the above-mentioned series of processes, the broadcast receiving device 100 of this embodiment creates/updates a list of services (service list) that make up the broadcast network when scanning channels during initial setup or when rescanning to change settings, and at the same time creates/updates a list of IP multicast groups (IP-related information) corresponding to each of the services, and further stores this information in non-volatile memory such as the ROM 103 or storage unit 110.

The rescan for the setting change may be performed automatically when a change in the information in the table is detected by referring to the "version_number" parameter of the TLV-NIT or AMT. When a change in the "version_number" parameter of either the TLV-NIT or AMT is detected, only the information about the table in which the change in the parameter was detected may be automatically updated. However, when the automatic update is performed, it is desirable to notify the user that a rescan has been performed automatically. Also, the user may be notified that a change has been made to the information in the table, and the user may choose whether or not to perform the rescan.

[Broadcast receiving device tuning process (channel switching)]
FIG. 14A is a diagram showing an example of an operation sequence when selecting a station (switching a channel) in the broadcast receiving device 100 of this embodiment.

When a user operates a remote control (not shown) to instruct channel switching, the receiving function execution unit 1102 interprets the command sent from the remote control and specifies the service ID of the desired service (S201). Next, the receiving function execution unit 1102 starts acquiring the AMT from the signal received by the tuner/demodulator unit 131. If the AMT is successfully acquired within a predetermined time (S202: Yes), information on a list of IP multicast groups corresponding to the service ID is acquired from the acquired AMT (S204). On the other hand, if the AMT is not successfully acquired within the predetermined time (S202: No), information on a list of IP multicast groups corresponding to the service ID is acquired (S204) by referring to IP-related information stored in the ROM 103 or storage unit 110 (S203). Note that the judgment process of S202 may not be performed and the IP-related information stored in the ROM 103 or storage unit 110 may always be referred to.

Next, the reception function execution unit 1102 starts acquiring the TLV-NIT from the received signal of the tuner/demodulator unit 131. If the TLV-NIT is successfully acquired within the predetermined time (S205: Yes), distribution system information for acquiring the IP data flow corresponding to the service ID is acquired from the acquired TLV-NIT (S207). On the other hand, if the TLV-NIT is not successfully acquired within the predetermined time (S205: No), the service list stored in the ROM 103 or the storage unit 110, etc. is referenced (S206) to acquire distribution system information for acquiring the IP data flow corresponding to the service ID (S207). Note that the determination process of S205 may not be performed, and the service list stored in the ROM 103 or the storage unit 110, etc. may always be referenced.

After acquiring the distribution system information in the process of S207, the reception function execution unit 1102 then controls the tuner/demodulation unit 131 with the frequency value indicated in the acquired distribution system information, receives the IP data flow corresponding to the service ID (S208), extracts the MMT data string from the received IP data flow, and outputs it to the separation unit 132.

In the separation unit 132, the transport processing unit 1102a acquires an MMTP packet with a packet ID of "0" from the input MMT data string (S209), and further acquires the MPT contained in the acquired MMTP packet (S210). Next, the transport processing unit 1102a refers to the "MMT_package_id_byte" parameter of the acquired MPT, and checks whether the lowest 16 bits of the "MMT_package_id_byte" parameter are the same value as the service ID. In the example of the data structure of the MPT shown in FIG. 7B, if the lowest 16 bits of the "MMT_package_id_byte" parameter are the same value as the service ID (S211: Yes), it is determined that the MMTP packet whose packet ID is "0" is an MMTP packet that contains data of the program corresponding to the service ID, and the process proceeds to MFU acquisition processing based on the information contained in the acquired MPT.

On the other hand, if the lowest 16 bits of the "MMT_package_id_byte" parameter are not the same value as the service ID (S211: No), it is determined that the MMTP packet with the packet ID of "0" is not an MMTP packet having data of a program corresponding to the service ID. In this case, the transport processing unit 1102a acquires the PLT again (S212) and confirms the packet ID (assumed to be x) of the MMTP packet transmitting the MPT having the "MMT_package_id_byte" parameter corresponding to the service ID by checking the acquired PLT (S213). Furthermore, the transport processing unit 1102a acquires an MMTP packet with a packet ID of "x" from the input MMT data string (S214) and acquires the MPT included in the acquired MMTP packet (S215). Furthermore, based on the information contained in the acquired MPT, it starts the MFU acquisition process.

It is also possible to always perform steps S212 to S215 without performing steps S209 to S211. In this case, it is possible to reduce the processing time when data for a program corresponding to the service ID is stored in an MMTP packet with a packet ID other than "0".

Here, the process of identifying the packet ID of an MMTP packet having data of a program corresponding to the service ID by checking the PLT and acquiring the MPT will be described. An MMTP packet with a packet ID of "0" indicates that it transmits a PA message. When multiple packages are multiplexed, as shown in FIG. 14B, this PA message includes a PLT (package list table). The PLT has a list of packet IDs of MMTP packets that transmit PA messages including MPTs of other packages, and by checking the PLT, it is possible to identify an MMTP packet that transmits a PA message including an MPT that is the entry point of each service from the package ID. An example of the data structure of a PLT is shown in FIG. 14C. The location information for transmitting the PA message of the package indicated by the "MMT_package_id_byte" parameter is specified by "MMT_general_location_info()".

Returning to the description of the operation sequence shown in FIG. 14A, in the MFU acquisition process, first, the transport processing unit 1102a refers to the MPT acquired in the process of S210 or S215, and acquires the IP address and packet ID of the IP data flow that transmits the desired MFU (S216). In addition, the transport processing unit 1102a acquires the presentation time of the MPU from the MPU timestamp descriptor arranged in the MPT, and the layout number of the MPU from the MPU presentation area designation descriptor arranged in the MPT (S217, S218), and further acquires the MFU based on the IP address and packet ID of the acquired IP data flow (S219). Next, the encoded video data and encoded audio data, etc. are extracted from the acquired MFU, and video/audio decoding processing is performed under the control of the AV decode processing unit 1102b, and presentation processing is performed based on the acquired information on the presentation time and information on layout control under the control of the presentation processing unit 1102h (S220).

If the PLT cannot be obtained in the process of S212, if the "MMT_package_id_byte" parameter matching the service ID cannot be confirmed in the process of S213, if an MMTP packet with a packet ID of "x" cannot be obtained in the process of S215, etc., program display processing (i.e., processing of S216 to S220) may be performed based on the data of the MMTP packet with a packet ID of "0" obtained in the process of S210. In this case, it is also good to display a message to the effect that the program corresponding to the service ID selected by the user could not be displayed.

The above series of processes enable the broadcast receiving device 100 of this embodiment to perform channel selection (channel switching) operations. In particular, as described with reference to FIG. 13A and FIG. 14A, when scanning channels during initial setup or when rescanning to change settings, a service list and IP-related information are created and stored in a non-volatile memory such as the ROM 103 or the storage unit 110 so that they can be referenced at all times, and when selecting a channel (switching a channel), the service list and IP-related information stored in the non-volatile memory such as the ROM 103 or the storage unit 110 are referenced, thereby improving the efficiency of operations during channel selection (switching a channel). In other words, it is possible to shorten the time from the start of channel selection (switching a channel) to the end of channel selection (switching a channel) compared to the case where AMT or TLV-NIT is reacquired during channel selection (switching a channel).

[Remote control key setting process for broadcast receiving device]
15A shows an example of the appearance of a remote control (remote controller) 100R used to input operation instructions to the broadcast receiving device 100 of this embodiment. The remote control 100R includes at least a power key 100R1, a numeric keypad 100R2, a channel up/down key 100R3, a menu key 100R4, an EPG key 100R5, a cursor key 100R6, a decision key 100R7, and a color key 100R8. The remote control 100R may further include volume up/down keys, a network switching key, an input switching key, a record key, a play key, etc.

For example, in the process of S201 of the operation sequence at the time of channel selection shown in FIG. 14A, when instructing the broadcast receiving device 100 of this embodiment to change channels using the remote control 100R, the following three methods may be used. The first method is to directly input and specify the service ID of the desired channel (service) by pressing the numeric keypad 100R2 multiple times. The second method is to perform forward (or reverse) channel selection until the desired channel (service) is displayed by repeatedly pressing the channel up/down key 100R3 as necessary. The third method is a so-called one-touch channel selection method in which a specific channel (service) associated with each key of the numeric keypad 100R2 is called up by pressing the numeric keypad 100R2 only once. The third method, one-touch channel selection, is a convenient channel selection method, but it is necessary to previously set the association of a specific channel (service) with each key of the numeric keypad 100R2 in the broadcast receiving device 100.

The broadcast receiving device 100 corresponding to the broadcasting system of this embodiment is capable of automatically setting the association based on the control information contained in the digital broadcast wave received by the tuner/demodulator unit 131. That is, the broadcasting system of this embodiment provides a remote control key descriptor as a TLV-SI descriptor. The association can be set by referring to the remote control key descriptor.

Figure 15B shows an example of the data structure of a remote control key descriptor. The "service_id" parameter in the figure is a service ID that identifies a channel (service). The "remote_control_key_id" parameter is a recommended value for the remote control button number to which the channel (service) identified by the service ID is assigned. Depending on the values of each of the above parameters, the channel (service) identified by the "service_id" parameter can be associated with the key specified by the value of the "remote_control_key_id" parameter of numeric keypad 100R2.

When there are many channels (services) in the same network, the channels (services) may be assigned to keys other than the numeric keypad 100R2. For example, a specific channel (service) may be assigned to the color key 100R8. In this case, a numerical value corresponding to the "remote_control_key_id" parameter may be assigned in advance to each key of the color key 100R8.

The remote control key descriptor may be described as a TLV-NIT descriptor. Therefore, for example, if the TLV-NIT acquired in the process of S103 of the channel scan operation sequence shown in FIG. 13A is valid data, the association can be set by storing the description contents of the remote control key descriptor in non-volatile memory such as ROM 103 or storage unit 110 of the broadcast receiving device 100 in conjunction with the processes of S105 to S107.

The association may be set according to the contents of the description of the remote control key descriptor as described above, or the user may assign services of any channel to each key of the numeric keypad 100R2 according to his/her preference. In addition, both the association setting according to the contents of the description of the remote control key descriptor and the association setting assigned by the user according to his/her preference may be stored simultaneously in the non-volatile memory of the broadcast receiving device 100, and only one of the settings may be used by selecting from a menu operation or the like. In this case, the association setting assigned by the user according to his/her preference may be used preferentially. In addition, according to the value of the priority flag described in the remote control key descriptor, the association setting according to the description of the remote control key descriptor may be used preferentially over the association setting assigned by the user according to his/her preference. The priority flag may be set by using part or all of the ``reserved'' parameter of the remote control key descriptor shown in FIG. 15B, or by adding a new parameter. In this case, the value of the priority flag may be controllable for each service ID.

In addition, if the non-volatile memory stores the association settings assigned by the user according to his/her preferences, the association settings according to the description contents of the remote control key descriptor may not be stored in the non-volatile memory. In addition, the non-volatile memory of the broadcast receiving device 100 may store only the association settings assigned by the user according to his/her preferences, and if a remote control key descriptor is described in the TLV-NIT being received, the association settings according to the description contents of the remote control key descriptor may be used, and if a remote control key descriptor is not described in the TLV-NIT being received, the association settings assigned by the user according to his/her preferences may be used.

The process of changing the association of each key of the numeric keypad 100R2 with a specific channel (service) according to the contents of the remote control key descriptor may be performed simultaneously for all services described in the service list descriptor in the network specified by the TLV-NIT, or may be performed only for some of the services. When performing the process only for some of the services, the old settings for the other services may be retained as they are. Also, when the "service_id" parameter is a specific value (e.g., 999), only the settings specified by the "remote_control_key_id" parameter may be erased from the settings stored in the non-volatile memory of the broadcast receiving device 100.

In other words, in the broadcast receiving device 100 of this embodiment, it is possible to set the association of a specific channel (service) with each key on the numeric keypad 100R2.

[Multi-channel selection process]
In the broadcasting system of this embodiment, it is also possible to perform a multi-format broadcast in which multiple programs are broadcast in parallel on one channel (service). When broadcasting multiple programs simultaneously using a multi-format, the one-touch channel selection described above is possible only for the main channel of the multi-format, but not for the subchannels of the multi-format. In other words, when selecting a subchannel of the multi-format, it is necessary to use a method of directly inputting and specifying a service ID, or to select the main channel of the multi-format once using one-touch channel selection, and then select the desired subchannel by pressing the channel up/down key 100R3, which results in a problem of cumbersome operations.

To solve the above problem, in the broadcast receiving device 100 of this embodiment, the one-touch channel selection function is expanded, and it is possible to directly select a subchannel of a multi-channel set by repeatedly pressing the numeric keypad 100R2, to which a specific service ID is assigned, multiple times within a specific period of time.

Explained with reference to FIG. 16A. For example, assume that the service of channel 011 is assigned in advance to the "1" key of the numeric keypad 100R2 of the remote control 100R. In this case, if a channel selection operation is performed when multi-organization is not performed (see (A) in the figure), channel 011 is selected regardless of the number of times the "1" key is pressed. On the other hand, if a channel selection operation is performed when multi-organization is performed (see (B) in the figure), channel 011 is selected when the "1" key is pressed only once, and channel 012 is selected when the "1" key is pressed again within a predetermined time from the first pressing of the "1" key. Similarly, when the "1" key is pressed three times within a predetermined time, channel 013 is selected. Note that if the "1" key is pressed again after a predetermined time has elapsed since the first pressing of the "1" key, channel 011 may remain selected.

By enabling the above-mentioned operations, the broadcast receiving device 100 of this embodiment allows direct selection of sub-channels during multi-channel programming with simpler operations.

Similarly, the angle of a multi-view compatible program or a specific video asset from multiple video assets may be selected by repeatedly pressing the numeric keypad 100R2 multiple times. As shown in FIG. 16B, when the service ID of a multi-view compatible program is assigned to the "1" key of the numeric keypad 100R2 of the remote control 100R, pressing the "1" key only once selects the multi-view compatible program and displays the main view. Pressing the "1" key again within a predetermined time from the first pressing of the "1" key displays the sub-view 1 of the multi-view compatible program. Similarly, pressing the "1" key three times within a predetermined time displays the sub-view 2 of the multi-view compatible program. If the "1" key is pressed again after a predetermined time has elapsed since the first pressing of the "1" key, the main view of the multi-view compatible program may remain displayed. Selection of a specific video asset from multiple video assets may also be possible by the same operations as described above.

By enabling the above-mentioned operations, the broadcast receiving device 100 of this embodiment makes it possible to select an angle for a multi-view compatible program or select a specific video asset from multiple video assets with simpler operations.

If one or more of the programs in the multi-format are multi-view compatible or have multiple assets, only one of the above operations can be enabled and the other disabled. For example, if one or more of the programs in the multi-format are multi-view compatible or have multiple assets, pressing the same key multiple times within a specified time period can be assigned to the direct selection of a sub-channel in the multi-format. Which operations are enabled and which are disabled can be determined in advance, or can be selected by the user.

[Screen layout control of broadcast receiving device]
In the broadcast receiving device 100 of this embodiment, it is assumed that screen layout control based on the description of the LCT is possible. An example of the data structure of the LCT is shown in Fig. 17A. An example of the data structure of the MPU presentation area specification descriptor is shown in Fig. 17B.

In the data structure of the LCT, the "left_top_pos_x" and "right_down_pos_x" parameters indicate the horizontal position of the top left and bottom right of the region, respectively, as a percentage of the total number of pixels in the horizontal direction, when the left side of the full screen display is "0" and the right side is "100". The "left_top_pos_y" and "right_down_pos_y" parameters indicate the vertical position of the top left and bottom right of the region, respectively, as a percentage of the total number of pixels in the vertical direction, when the top side of the full screen display is "0" and the bottom side is "100". The "layer_order" parameter indicates the relative position of the region in the depth direction.

An example of assigning layouts to layout numbers based on the settings of each of the above parameters is described below, along with the setting values of each of the above parameters.

Figure 17C shows the default layout setting of the broadcast receiving device 100 of this embodiment, and is an example in which only one area is set on the entire screen. Figure 17D shows an example in which the entire screen is divided into three areas, each of which is designated as "Area 0", "Area 1", and "Area 2". For example, if the number of pixels on the entire screen is 7680 pixels horizontally and 4320 pixels vertically, "Area 0" is set to the range (0,0)-(6143,3455) since the "left_top_pos_x" parameter is "0", the "left_top_pos_y" parameter is "0", the "right_down_pos_x" parameter is "80", and the "right_down_pos_y" parameter is "80". Similarly, "Area 1" is set to the range (6144,0)-(7679,4319), and "Area 2" is set to the range (0,3456)-(6143,4319).

Figure 17E is an example of setting three regions, similar to Figure 17D, but "region 0" is set in the range of (0,0)-(7679,4319), and "region 1" and "region 2" are placed in front of "region 0" in the same range as above, according to the setting of the "layer_order" parameter. Figure 17F is an example of the case where "region 0" is set in device 0 (default device: in this example, broadcast receiving device 100), and "region 1" is set in device 1 (in this example, mobile information terminal 700).

As mentioned above, in the broadcasting system of this embodiment, by using LCT, it becomes possible to perform screen layout control to display multimedia services on the receiver as intended by the service provider.

In addition, in areas where program video or data screens are not displayed due to the above-mentioned screen layout control, a predetermined background color specified by the background color specification descriptor described in the LCT may be displayed. Furthermore, if the LCT does not contain the background color specification descriptor, if the broadcast receiving device 100 is unable to correctly acquire the background color specification descriptor, if the predetermined background color specified by the background color specification descriptor cannot be displayed due to hardware limitations, etc., the video display device 100 may display a predetermined pattern in the area. Furthermore, the area may be used as an area for displaying notifications from the video display device 100 to the user. The notifications may be any information.

When dividing the screen according to the set values of parameters such as "left_top_pos_x", fractions after the decimal point may be rounded up or down. Rounding (or rounding down to the nearest whole number in binary) may also be used. For example, if the number of pixels on the entire screen is 7680 pixels/4320 pixels vertically, and the "left_top_pos_x" parameter of "Area 0" is "0", the "left_top_pos_y" parameter is "0", the "right_down_pos_x" parameter is "51", and the "right_down_pos_y" parameter is "51", "Area 0" may be set in the range of (0,0)-(3916,2203) by rounding up, or in the range of (0,0)-(3915,2202) by rounding down. Also, taking into account macroblocks during video compression processing, rounding up/down processing in 8-pixel or 16-pixel units may be performed. This processing makes it possible to efficiently set regions based on the LCT and perform resolution conversion processing of multimedia content in the regions.

Alternatively, the set values of parameters such as "left_top_pos_x" may be limited to only "multiples of 5" or "multiples of 10" in the range from "0" to "100". In this case as well, the area setting can be performed appropriately.

The content to be displayed in each of the above-mentioned areas is specified by the MPU presentation area specification descriptor shown in FIG. 17B. The content of the MPU whose sequence number is specified by the "mpu_sequence_number" parameter in the figure is associated with the description of the above-mentioned LCT by the "layout_number" parameter and the "region_number" parameter.

In addition, within the first 'for' loop of the description of the MPU presentation area designation descriptor, multiple 'layout_number' parameters and 'region_number' parameters may be described for one 'mpu_sequence_number' parameter, allowing the user to select which description to use for layout control. For example, in the first "for" loop, if a "layout_number1", "region_number1", "layout_number2" and "region_number2" parameters are described for a specific "mpu_sequence_number" parameter, the user can select whether the layout control of the MPU specified by the "mpu_sequence_number" parameter is to be performed based on the "layout_number1" and "region_number1" parameters, or based on the "layout_number2" and "region_number2" parameters. In this way, the user can perform layout control for a video program according to their preferences.

[Exception handling of screen layout control in broadcast receiving device]
In the broadcast receiving device 100 of this embodiment, even if the screen layout area control is performed by the above-mentioned LCT, when the user instructs to display an EPG screen, etc., it is possible to perform screen layout control that ignores the contents of the LCT as an exceptional process. Figure 18A shows an example of the operation of the exceptional process of the screen layout control based on the LCT.

When the same screen layout control as in FIG. 17D is performed according to the description in the LCT, and broadcast program video is displayed in "Area 0", and broadcast content such as program linkage data linked to the broadcast program is displayed in "Area 1" and "Area 2", and the user instructs the display of the EPG screen using a remote control (not shown), the broadcast receiving device 100 of this embodiment returns the screen layout setting to the default setting (i.e., a state in which the same screen layout control as in FIG. 17C is being performed) regardless of the contents of the description in the LCT, as shown in FIG. 18A (A), and controls the EPG screen to be displayed on the entire screen. Furthermore, when the user instructs the display of the EPG screen to end, the screen layout control according to the contents of the description in the LCT is re-executed.

By performing the above-mentioned control, the EPG screen can be displayed larger and easier to view than when the EPG screen is displayed while maintaining area control of the screen layout as shown in FIG. 18A (B).

The above-mentioned exception processing of the screen layout control is not only applied when the EPG screen is displayed, but may also be applied when a sub-screen or dual-screen display is displayed for various setting screens (the recording setting screen in the illustrated example) of the broadcast receiving device 100, as shown in FIG. 18B.

In the case of the recording setting screen shown in FIG. 1A, the display area of the broadcast content is changed from the entire screen to only the sub-screen portion at the bottom right of the screen. Similarly, in the case of the dual-screen display shown in FIG. 1B, the display area of the broadcast content is changed from the entire screen to only the split screen portion at the left middle section of the screen. In either case, the display area for displaying the broadcast content is narrower than when the entire screen is used, so maintaining the area control of the screen layout within the display area (i.e., dividing the area to display multiple broadcast contents simultaneously) is not desirable from a visual standpoint. Therefore, in the broadcast receiving device 100 of this embodiment, in the above situation, only the broadcast content in "Area 0" is selected and displayed in the display area. Note that it is also possible to select and display the broadcast content in "Area 1" or "Area 2" depending on the immediately preceding area selection situation.

By performing the above-mentioned control, it is possible to improve the ease of viewing the broadcast content compared to when various broadcast contents are displayed while maintaining area control of the screen layout. The same is true when displaying a sub-screen on the recorded program list screen, when displaying Internet content in a browser, etc.

[Video signal aspect ratio conversion processing]
The aspect ratio of the video signal in the television broadcasting service includes "4:3" used in conventional SDTV, "16:9" used in recent HDTV, and "21:9" suitable for movie content. In the broadcasting system of this embodiment, the information on the aspect ratio of the video signal may be described by a video component descriptor. FIG. 19A shows an example of the data structure of the video component descriptor. In the figure, the "video_aspect_ratio" parameter is information on the aspect ratio of the video signal. FIG. 19B shows an example of the meaning of the "video_aspect_ratio" parameter. An aspect ratio different from that shown in the figure may be further assigned.

On the other hand, the aspect ratio of the display of a television receiver capable of receiving the television broadcast service (such as the broadcast receiving device 100 of this embodiment) is generally 16:9. In other words, when displaying video content with an aspect ratio of 4:3 or 21:9 on a general television receiver, aspect ratio conversion processing may be performed.

Whether or not to perform the aspect ratio conversion process can be determined by comparing the specifications of the monitor unit 162 of the broadcast receiving device 100 with the "video_aspect_ratio" parameter of the video component descriptor. For example, if the aspect ratio of the monitor unit 162 of the broadcast receiving device 100 is "16:9" (e.g., 3840 pixels horizontal by 2160 pixels vertical), the aspect ratio conversion process is not performed if the value of the "video_aspect_ratio" parameter is "0", "2", or "3", and the aspect ratio conversion process is performed if the value is "1" or "5". Also, for example, if the aspect ratio of the monitor unit 162 of the broadcast receiving device 100 is "21:9" (5040 pixels horizontal by 2160 pixels vertical, etc.), aspect ratio conversion processing will not be performed if the value of the "video_aspect_ratio" parameter is "0" or "5," and aspect ratio conversion processing will be performed if the value is "1," "2," or "3."

19C and 19D show an example of the aspect ratio conversion process when the aspect ratio of the monitor unit 162 of the broadcast receiving device 100 is "16:9" and the value of the "video_aspect_ratio" parameter is "5". When displaying video content with an aspect ratio of "21:9" on the monitor unit 162 with an aspect ratio of "16:9", the aspect ratio may be converted to "16:9" by adding black bands above and below the video content with an aspect ratio of "21:9" (display A in the figure). In this way, it is possible to display the entire area of the original video content without distortion. Also, only the center part of the video content with an aspect ratio of "21:9" may be cut out and displayed on the monitor unit 162 (display B in the figure). In this way, it is possible to display the main part of the original video content in a large size. Also, it is possible to add a few black bands above and below the video content with an aspect ratio of "21:9" and further cut out the center part (display C in the figure). In this way, it is possible to display most of the original video content in a large size. It is also possible to compress the left and right edges of video content with an aspect ratio of 21:9 to display the entire area (display D in the figure). In this way, it is possible to display the entire area of the original video content in a large size, with the main part displayed without distortion. It is also possible to add small black bands to the top and bottom of video content with an aspect ratio of 21:9, and further compress the left and right edges to display the entire area (display E in the figure). In this way, it is possible to display the entire area of the original video content in a large size, with less distortion at the left and right edges.

The way in which the aspect ratio conversion process is performed may be selectable by the user through settings such as a menu. Alternatively, it may be possible to switch by pressing a specific key on a remote control or the like. Note that the aspect ratio "21:9" mentioned above includes aspect ratios that are roughly "21:9", such as the so-called Cinemascope "2.35:1". The same applies to other aspect ratio values.

[EPG display on broadcast receiving device]
In the broadcasting system of this embodiment, time-series information on events (so-called programs) included in each service constituting the broadcasting network is transmitted by MH-EIT. The MH-EIT shown in FIG. 7E is identified into two classes by table ID (corresponding to the "table_id" parameter in the figure), and is capable of indicating information on the current/next event of the own TLV stream and schedule information of each event of the own TLV stream. The broadcast receiving device 100 of this embodiment is capable of acquiring information such as the start time and broadcast time of each event by identifying the event by service ID (corresponding to the "service_id" parameter in the figure) with reference to the MH-EIT, etc., and creating an EPG screen, and is capable of superimposing the created EPG on video information, etc. by the video synthesis unit 161 and displaying it on the monitor unit 162.

Figure 20A is a diagram showing an example of an EPG screen in the broadcast receiving device 100 of this embodiment. The EPG screen 162a is in a matrix shape with the vertical axis indicating time and the horizontal axis indicating service ID (channel), and displays detailed information on broadcast programs broadcast on each channel in each time period. In addition, the detailed information 162a1 of each broadcast program is mainly composed of a title area 162a2 and a detailed explanation area 162a3. The detailed information 162a1 of each broadcast program may display program information described in an MH-short format event descriptor or an MH-extended format event descriptor and distributed. If the capacity of the program information described in each of the descriptors is large, it may be displayed in abbreviated form under normal circumstances, and when selected by operating a remote control (not shown), all program information may be displayed in a pop-up or the like. Alternatively, when selected, the program information described in each of the descriptors may be transmitted to the mobile information terminal 700 in the linked operation, and the mobile information terminal 700 may be instructed to display it on the display unit 741.

The title area 162a2 of the detailed information 162a1 of each broadcast program displays the program title of the broadcast program and symbols and the like representing the attributes of the broadcast program. The symbols and the like representing the attributes of the broadcast program are, for example, symbols/characters indicating that it is a new program, or symbols/characters indicating that it is a rebroadcast program, etc. Alternatively, it may be a symbolized mark such as "data", which means that it supports data broadcasting by a broadcasting service. It may also be a symbolized mark 162a4 such as "Network", which means that content, applications, etc. related to the broadcast program can be obtained from the network. Furthermore, the symbols and the like representing the attributes of the broadcast program may be replaced by differentiating the background color of the detailed information 162a1 from others, or by surrounding the display area of the detailed information 162a1 with a thick frame.

Even if the control information (messages, tables, descriptors, etc.) in the broadcasting system of this embodiment indicates that content, applications, etc. related to the broadcast program can be obtained from the network, if the LAN cable is not connected to the LAN communication unit 121 of the broadcast receiving device 100, or if access to each server device on the network is not possible, the mark 162a4 symbolizing "Network" etc. may be controlled not to be displayed.

In addition, when the broadcast program is a distributed program distributed via the Internet 200 and cannot be acquired only from the broadcast wave, and further, as described above, when the broadcast receiving device 100 is in a state where it cannot access each server device on the network, the detailed information 162b1 displayed on the EPG screen 162b may be controlled to be grayed out as shown in FIG. 20B. That is, the detailed information of the distributed program that cannot be viewed is controlled not to be displayed. In addition, the background color of the detailed information 162b1 may be differentiated from the others as an alternative to the graying out process. Alternatively, a message such as "This program cannot be viewed" may be displayed in the detailed explanation area 162a3 of the distributed program. When the detailed information 162b1 is selected by operating the remote control (not shown), the user may be notified by a pop-up or the like that the broadcast receiving device 100 is in a state where it cannot access each server device on the network, or that the distributed program associated with the detailed information 162b1 cannot be viewed.

Through the above-mentioned controls, the broadcast receiving device 100 is able to provide the user with program information for each broadcast program in a format that feels more natural to the user, depending on the network connection status.

Figure 20C is a diagram showing another example of an EPG screen in the broadcast receiving device 100 of this embodiment. In the figure, "M1 Television", "M2 Broadcast", "M3 Channel", "M4 TV", "Television M5", etc. are the broadcast station names for each channel, and in particular, the "M2 Broadcast" station simultaneously provides broadcast programs distributed by airwaves and distributed programs distributed via the Internet 200 (slot information 162c1 indicated by "Internet Broadcast" in the figure).

As shown in the figure, when there is a channel that only has programs distributed via the Internet 200, the EPG screen 162c in the figure (A) is normally controlled to display information for all channels (including information 162c1). On the other hand, when the broadcast receiving device 100 is in a state where it cannot access each server device on the network, the EPG screen 162d in the figure (B) may be controlled not to display information for the "M2 Broadcast (Internet Broadcast)" channel (information 162c1 in the figure (A)), which only has programs distributed via the Internet 200.

The above-mentioned controls make it possible for users of the broadcast receiving device 100 to avoid having to check information about channels that they cannot watch.

[Emergency warning broadcast display on broadcast receiving device]
The broadcast receiving device 100 of this embodiment is capable of performing receiving processing of an emergency alert broadcast when the emergency alert broadcast start control signal bit of the TMCC signal contained in the transmission data including the TLV stream changes from "0" to "1."

The emergency alert broadcast may be provided as a broadcast program on a dedicated channel (service ID), as a full-screen application, or as text information with superimposed text. When the emergency alert broadcast is provided as text information with superimposed text, it is preferable to display the text information of the superimposed text, regardless of the state of the broadcast receiving device 100 immediately before receiving the emergency alert broadcast. That is, as shown in FIG. 21, when a user is watching a normal broadcast program and an emergency alert broadcast is received while a program screen 162e of the broadcast program is displayed on the monitor unit 162, the text information 162e1 of the emergency alert broadcast is superimposed on the program screen 162e. Similarly, when a user instructs the display of an EPG screen and an emergency alert broadcast is received while an EPG screen 162f is displayed on the monitor unit 162, the text information 162f1 of the emergency alert broadcast is superimposed on the EPG screen 162f.

By the above-mentioned control, in the broadcast receiving device 100 of this embodiment, even if the user selects and displays an EPG screen, various setting screens, a recorded program list screen, an Internet browser, etc., when an emergency alert broadcast is received, it is possible to avoid missing important text information based on the emergency alert broadcast. Note that this control may also be performed on text information of normal text superimpositions that are not based on emergency alert broadcasts.

In addition, when the emergency alert broadcast is provided as a broadcast program on a dedicated channel (service ID), the channel (service ID) of the emergency alert broadcast may be automatically selected regardless of the channel (service ID) of the currently viewed program. In addition, when the emergency alert broadcast is provided as a broadcast program on a dedicated channel (service ID) or as an application, the emergency alert broadcast program or application may be distributed to a linked external mobile terminal device (such as the mobile information terminal 700 in this embodiment) under the control of the linking function execution unit 1103.

In addition, if the power of the broadcast receiving device 100 is not on when the emergency alert broadcast is distributed, the broadcast receiving device 100 may be controlled to be automatically powered on. Alternatively, the broadcast receiving device 100 may be controlled to transmit a notification that an emergency alert broadcast has started to a mobile information terminal 700 that has a history of linked operation with the broadcast receiving device 100.

By using the above-mentioned control, the broadcast receiving device 100 of this embodiment makes it possible to avoid missing important broadcast programs or application images based on the emergency alert broadcast.

[Display control exception handling]
In the broadcast receiving device 100 of this embodiment, if data that constitutes the same package is transmitted via a path other than the TLV stream, the broadcast receiving device 100 may perform, for example, exceptional processing such as that described below.

As described with reference to FIG. 7A, in the broadcast system supported by the broadcast receiving device 100 of this embodiment, data acquired from the TLV stream and data acquired from a path other than the TLV stream can be included in the same package based on the location information stored in the MPT (see FIG. 7C). However, data transmitted on a data transmission path other than the TLV stream (for example, an IPv4 data flow or an IPv6 data flow on a communication line, or an MPEG2-TS on a broadcast) indicated by the location information is data acquired by a receiving function other than the TLV/MMT stream receiving function. Therefore, even when the broadcast receiving device 100 is operating, there may be a situation in which data cannot be acquired from these transmission paths, such as a situation in which the receiving function of these transmission paths is not operating, a situation in which the receiving function itself is operating but a relay device on the transmission path is not operating, a situation in which these transmission paths are not connected by wire or wirelessly, or a situation in which the broadcast receiving device 100 is installed in an environment in which these transmission paths cannot be connected in the first place.

Under such circumstances, when an event is received in which the location information stored in the MPT indicates that data obtained from the TLV stream and data obtained from a route other than the TLV stream are to be associated so as to be included in the same package, the broadcast receiving device 100 of this embodiment may perform the following operations.

For example, in the case where the LCT sets multiple regions in the screen as shown in FIG. 17D or FIG. 17E, and the program video based on the data acquired from the TLV stream is displayed in "region 0", and the content based on the data acquired from a transmission path other than the TLV stream is displayed in "region 1" or "region 2", and if the data of the transmission path other than the TLV stream to be displayed in "region 1" or "region 2" cannot be acquired, the layout display of the multiple regions specified by the LCT may be prohibited. Specifically, even if the LCT is received, the program video based on the data acquired from the TLV stream may be left in the "region 0" of the default layout display shown in FIG. 17C, and the layout display of the multiple regions may not be changed to that shown in FIG. 17D or FIG. 17E. Furthermore, even if an instruction to change the default layout to the layout indicated by the LCT is input to the operation input unit 170 of the broadcast receiving device 100 in this state, the default layout display shown in FIG. 17C may be left as it is, or the display may be switched to another data broadcast screen, so that the layout display of the multiple regions may not be changed to that shown in FIG. 17D or FIG. 17E.

In addition, in a case where the LCT sets multiple regions within the screen as shown in Figures 17D and 17E, and program video based on data obtained from the TLV stream is displayed in "Area 0," and content based on data obtained via a transmission path other than the TLV stream is displayed in "Area 1" and "Area 2," and data from a transmission path other than the TLV stream to be displayed in "Area 1" or "Area 2" cannot be obtained, another example of operation can be to first display the display frames of the multiple regions shown in Figures 17D and 17E indicated by the LCT, and display a background color or a specified still image in "Area 1" or "Area 2." If data from a transmission path other than the TLV stream indicated by the MPT location information cannot be obtained even after a specified time has elapsed, the display can be switched back to the default layout display state shown in Figure 17C. In this case, when changing from the layout of FIG. 17C to the layout of FIG. 17D or FIG. 17E, and when changing from the layout of FIG. 17D or FIG. 17E to the layout of FIG. 17C, if the program video based on the data obtained from the TLV stream continues to be displayed in "Area 0" of each layout, this is preferable because it allows the user to continue watching the program video.

In addition, when the program video based on the data acquired from the TLV stream is displayed in "Area 0" of the default layout display shown in FIG. 17C due to the inability to acquire data of the transmission path other than the TLV stream to be displayed in "Area 1" or "Area 2", the operation of various communication functions and various reception functions of the broadcast receiving device 100 of this embodiment may start, or the communication environment/communication status of the various communication functions or the reception environment/reception status of the various reception functions may change, resulting in a situation in which data of the transmission path other than the TLV stream to be displayed in "Area 1" or "Area 2" can be acquired. In this case, the broadcast receiving device 100 of this embodiment may immediately switch from the default layout display shown in FIG. 17C to a layout of multiple areas as shown in FIG. 17D or FIG. 17E shown by the LCT, and may display the program video based on the data acquired from the TLV stream in "Area 0", and display content based on the data acquired from a transmission path other than the TLV stream in "Area 1" or "Area 2". Alternatively, the layout change may not be performed immediately, but may be performed after an instruction to change from the default layout to the layout indicated by the LCT is input from the operation input unit 170. In this case, it is preferable to notify the user that the layout change is possible by an OSD display or the like.

[Copyright protection function]
In a digital broadcasting system compatible with the broadcast receiving device 100 of this embodiment, copy control information may be included in the MPT or the like and transmitted to indicate the copy control status of the content referred to by the MPT or the like, such as "unlimited copying permitted" (which may be divided into two types: "unlimited copying permitted and encryption processing required when storing and outputting" and "unlimited copying permitted and encryption processing not required when storing and outputting"), "one generation only copying permitted", "a specified number of times of copying permitted" (for example, so-called "dubbing 10" if nine copies and one move permitted), and "copy prohibited". In this case, the broadcast receiving device 100 of this embodiment may be configured to control the storage of the content in the storage (storage) unit 110, recording on a removable recording medium, output to an external device, copying to an external device, moving to an external device, etc., according to the copy control information.

The target of the accumulation process may be not only the storage (accumulation) unit 110 inside the broadcast receiving device 100, but also removable recording media and external devices that have been subjected to protection processes such as encryption so that they can be played back only by the broadcast receiving device 100. Specifically, for example, this includes external recording devices such as HDDs connected to the expansion interface unit 124 that can be recorded and played back only by the broadcast receiving device 100.

<Content Copy Control>
A specific example of the content copy control process based on the copy control information will be described below.

First, when the copy control information included in the MPT or the like indicates "unlimited copying", the broadcast receiving device 100 of this embodiment may perform storage in the storage unit 110, recording on a removable recording medium, output to an external device, copying to an external device, moving to an external device, etc., without restrictions. However, when the control based on the copy control information is divided into "unlimited copying and encryption processing required at the time of storage and output" and "unlimited copying and no encryption processing required at the time of storage and output", and indicates "unlimited copying and encryption processing required at the time of storage and output", storage in the storage unit 110, recording on a removable recording medium, output to an external device, copying to an external device, moving to an external device, etc. may be performed without restrictions, but encryption processing is required for all of them.

In addition, when the copy control information included in the MPT or the like indicates "copyable for one generation only," the broadcast receiving device 100 of this embodiment may be able to encrypt and store the content in the storage (accumulation) unit 110, or record the content on a removable recording medium that has been subjected to a protection process such as encryption so that the content can be played back only by the broadcast receiving device 100. In addition, when the stored content is output to an external device for viewing, it is encrypted and output together with copy control information indicating "copy prohibited." In addition, so-called move processing to an external device (processing in which the content is copied to an external device and the content in the storage (accumulation) unit 110 of the broadcast receiving device 100, etc., is made unplayable by erasing the content, etc.) is possible.

In addition, when the copy control information included in the MPT or the like indicates that copying is permitted a specified number of times, the broadcast receiving device 100 of this embodiment may encrypt and store the content in the storage unit 110, or record the content on a removable recording medium that has been protected by encryption or other means so that it can only be played by the broadcast receiving device 100. In addition, when the stored content is output to an external device for viewing, it is encrypted and output together with copy control information indicating "copy prohibited." In addition, copying and moving to an external device a predetermined number of times may be permitted. In the case of the so-called "dubbing 10" provision, nine copies to an external device and one move can be performed.

In addition, when the copy control information included in the MPT or the like indicates "copy prohibited", the broadcast receiving device 100 of this embodiment prohibits storage (copying) in the storage (accumulation) unit 110 or the like. However, the broadcast receiving device 100 may be configured to have a "temporary storage" mode that allows storage in the storage (accumulation) unit 110 or the like only for a predetermined time or a predetermined time specified by control information included in the broadcast signal (for example, by an MH-Expire descriptor or a content usage control descriptor, etc.). In this case, even if the copy control information included in the MPT or the like indicates "copy prohibited", the broadcast receiving device 100 allows temporary storage of the content in the storage (accumulation) unit 110 or the like. When the content whose copy control information included in the MPT or the like indicates "copy prohibited" is output to an external device for viewing, it is encrypted and output together with the copy control information of "copy prohibited".

The output for viewing to the aforementioned external device may be performed via the video output unit 163 and audio output unit 166 of the broadcast receiving device 100 of this embodiment, or via the digital I/F unit 125 or LAN communication unit 121, etc. The copy or move process to the aforementioned external device may be performed via the digital I/F unit 125 or LAN communication unit 121, etc.

Figure 22A shows an example of the data structure of a content copy control descriptor in the broadcasting system of this embodiment. The "digital_recording_control_data" parameter in the figure is digital copy control information, and indicates information that controls the copy generation of the content. Also, Figure 22B shows an example of the parameter value of the digital copy control information and its meaning. For example, when the parameter is "00", it indicates "unlimited copying", when the parameter is "01", it can be defined by the business operator, when the parameter is "10", it indicates "one generation copying only", and when the parameter is "11", it indicates "copying prohibited". Also, Figure 23 shows an example of the data structure of a content usage control descriptor in the broadcasting system of this embodiment. The "copy_restriction_mode" parameter in the figure is copy restriction mode, and indicates whether or not number-limited copying is possible.

In the broadcast receiving device 100 of this embodiment, when the digital copy control information is "01", it is possible to execute a storage process that allows a predetermined number of copies determined in advance by the broadcasting company. Alternatively, when the digital copy control information is not "11" and the copy restriction mode indicates that a limited number of copies are permitted, it may be possible to execute a storage process that allows a predetermined number of copies determined in advance by the broadcasting company. Alternatively, in this case, the number of copies that can be made for each content may be specified by using part or all of the "reserved_future_use" parameter in the digital content usage descriptor.

By performing the above process, the broadcast receiving device 100 of this embodiment can realize the content copy control described above in which copying is permitted a specified number of times.

The "retention_mode" parameter in the content usage control descriptor shown in FIG. 23 is a temporary storage control bit, which indicates whether temporary storage of the target content is permitted when the digital copy control information indicates "copy prohibited." The "retention_state" parameter is a temporary storage allowable time, which indicates the temporary storage allowable time when the temporary storage allowable bit allows temporary storage of the target content.

In the broadcast receiving device 100 of this embodiment, by referring to the information on the temporary storage control bit and the temporary storage allowable time, it is possible to control whether or not temporary storage is permitted and the storage time when the digital copy control information for each content indicates "copy prohibited."

The process described above makes it possible to achieve appropriate content protection according to the copy control information associated with the content.

<Content output control>
Next, a specific example of the process of controlling the output of content to an external device will be described below.

In the content usage control descriptor shown in FIG. 23, the "image_constraint_token" parameter is a resolution restriction bit, which indicates whether or not image quality restriction is required when outputting the content to an external device. If the resolution restriction bit indicates that image quality restriction is required, the broadcast receiving device 100 of this embodiment restricts the image quality of the target content when outputting the target content to an external device. Note that the image quality restriction may not be required when storing the target content in the storage (accumulation) unit 110, etc. The image quality restriction may be, for example, converting the received (or stored) UHD (7680 pixels x 4320 pixels) video content into SHD (3840 pixels x 2160 pixels) video and outputting it, or converting HD (1920 pixels x 1080 pixels) video into SD (640 pixels x 480 pixels) video and outputting it. In addition, the extent to which the image quality of the target content is restricted, i.e., the resolution at which the image quality after the image quality restriction is to be achieved, may be specified by using part or all of the "reserved_future_use" parameter in the digital content usage descriptor.

As described above, for example, a frame rate limit bit or a pixel resolution limit bit may be prepared using part or all of the "reserved_future_use" parameter to control the frame rate limit or pixel resolution limit when the content is output to an external device. If the frame rate limit bit indicates that a frame rate limit is necessary, the broadcast receiving device 100 of this embodiment limits the frame rate of the target content when outputting the target content to an external device. For example, a video content with a frame rate of 120 Hz may be converted to a frame rate of 60 Hz and output. Also, if the pixel resolution limit bit indicates that a pixel resolution limit is necessary, the broadcast receiving device 100 of this embodiment limits the resolution of each pixel of the target content when outputting the target content to an external device. For example, each pixel of a video content with 12 bits per pixel may be converted to 8 bits and output.

Furthermore, a resolution restriction control flag, a frame rate restriction control flag, or a pixel resolution restriction control flag may be prepared by using part or all of the "reserved_future_use" parameter, and whether or not to restrict the image quality, frame rate, or pixel resolution may be controlled according to the resolution restriction control flag, frame rate restriction control flag, or pixel resolution restriction control flag. For example, if the resolution restriction control flag indicates that resolution restriction control is to be performed according to the interface specifications, control may be performed so that the image quality restriction is not performed if the interface that outputs the target content has a specified content protection technology, and the image quality restriction is performed if the interface does not have the specified content protection technology.

Specifically, for example, when the digital interface unit 125 is an HDMI interface and the target content is output to an external device connected to the HDMI interface, if the HDMI interface of the external device supports HDCP (High-bandwidth Digital Content Protection) version 2.2 or later, the target content is output without the image quality restriction, and if the HDCP version of the HDMI interface of the external device is less than 2.2, the target content is output with the image quality restriction. In other words, whether or not to restrict the image quality of the target content may be controlled depending on whether or not the interface that outputs the target content has a predetermined content protection technology, or if the interface has the content protection technology, depending on the version of the content protection technology. Note that if the resolution restriction control flag does not indicate that the resolution restriction control is performed according to the interface specifications, the presence or absence of the image quality restriction may be controlled depending only on the resolution restriction bit. Similar processing may be performed for the frame rate restriction control flag and the pixel resolution restriction control flag.

In addition, the copying process to an external device via the LAN communication unit 121 of content whose copy control information indicates copy restrictions such as "Copyable for one generation only," "Copyable a specified number of times," or "Copying prohibited" is permitted only when the IP address of the external device that is the destination of the packet transmitted from the broadcast receiving device 100 is in the same subnetwork as the IP address of the broadcast receiving device 100, and may be prohibited when the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100. Content whose copy control information indicates "Copyable without limit and requires encryption processing when stored and output" may also be handled in the same manner.

Similarly, for content whose copy control information indicates copy restrictions such as "copyable for one generation only," "copyable a specified number of times," or "unlimited copying with encryption required when storing and outputting," once stored in the storage unit 110, moving or copying to an external device via the LAN communication unit 121 is only possible if the IP address of the external device that is the destination of the packet sent from the broadcast receiving device 100 is in the same subnetwork as the IP address of the broadcast receiving device 100, and may be prohibited if the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100.

In addition, the video output and audio output for viewing of the content stored in the storage (accumulation) unit 110 of the broadcast receiving device 100 are, in principle, only possible when the IP address of the external device that is the destination of the transmission packet from the broadcast receiving device 100 is in the same subnetwork as the IP address of the broadcast receiving device 100, and are prohibited when the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100. However, if the external device is connected within the same subnetwork as the IP address of the broadcast receiving device 100 within a specified period of time and is a device that has been registered (paired) as a device that can be viewed even outside the same subnetwork as the IP address of the broadcast receiving device 100, it may be configured to enable the video output and audio output for viewing of the content stored in the storage (accumulation) unit 110 of the broadcast receiving device 100 to the external device even if the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100. In this case, the video output and audio output for viewing are performed by encrypting the content.

However, the encryption process may be controlled according to the value of the "encryption_mode" parameter of the content usage control descriptor shown in FIG. 23. That is, if the value of the "encryption_mode" parameter indicates that output protection of the IP interface output is required, the encryption process may be performed, and if the value indicates that output protection of the IP interface output is not required, the viewing video output and audio output may be performed without performing the encryption process. Also, if the value of the "encryption_mode" parameter indicates that output protection of the IP interface output is required, the range of IP addresses of external devices that can perform the viewing video output and audio output without performing encryption process may be specified by using part or all of the "reserved_future_use" parameter of the content usage control descriptor. That is, for a predetermined IP address, viewing video output and audio output are possible even if the IP address is not in the same subnet as the IP address of the broadcast receiving device 100.

The period during which the registration process (pairing) is valid may be specified by using part or all of the "reserved_future_use" parameter of the content usage control descriptor. In this case, if the date and time when the registration process (pairing) of the external device is performed is within the specified period, the output of video and audio for viewing to the external device may be permitted even if the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100, but may not be permitted if it is outside the specified period.

In addition, the above-mentioned processes of moving, copying, outputting, etc. of the content to an external device via the LAN communication unit 121 may be controlled according to the value of the "remote_view_mode" parameter of the content usage control descriptor. In other words, if the value of the "remote_view_mode" parameter does not allow remote viewing of the target content, control may be performed to prohibit all processes of moving, copying, outputting, etc. of the content to an external device via the LAN communication unit 121.

The process described above allows for appropriate content protection even when outputting content to an external device.

<Content Copy Control Exception Processing 1>
In the data structure of the content copy control descriptor shown in Fig. 22A, the first digital copy control information (the "digital_recording_control_data" parameter located immediately after "descriptor_length") is copy generation control information for the entire content, and the second digital copy control information (the "digital_recording_control_data" parameter located immediately after "component_tag") is copy generation control information for each of the components that make up the content. Each component is specified by the "component_tag" parameter.

In the broadcasting system of this embodiment, when controlling the copy generation of the entire content (program), only the first digital copy control information is described in the content copy control descriptor, and the copy generation is controlled by the first digital copy control information. On the other hand, when controlling the copy generation for each component that makes up the content, both the first digital copy control information and the second digital copy control information are described in the content copy control descriptor, and copy generation is controlled. Furthermore, when controlling the copy generation for each component that makes up the content, a situation may be considered in which the descriptions of the first digital copy control information and the second digital copy control information described in the content copy control descriptor do not match. In the above situation, the broadcast receiving device 100 of this embodiment may perform the operations shown below.

First, the first operation example is a method of controlling operation based on the copy generation control indicated in the first digital copy control information when the descriptions in the first digital copy control information and the second digital copy control information do not match. In this case, simple copy generation control common to each component that constitutes the same content is possible.

Next, the second operation example is a method of controlling operation based on the copy generation control indicated in the second digital copy control information when the descriptions in the first digital copy control information and the second digital copy control information do not match. In this case, different copy generation control is possible for each component even if the components make up the same content, which means more precise copy generation control is possible.

Furthermore, a third operation example is a method of controlling operation based on the digital copy control information with the stricter conditions of the two different digital copy control information when the descriptions in the first digital copy control information and the second digital copy control information do not match. For example, if one is "unlimited copying permitted" and the other is "one generation copying permitted," the information "one generation copying permitted" is followed. Or, if one is "a specified number of copies permitted" and the other is "copying prohibited," the information "copying prohibited" is followed. Or, if both are "a specified number of copies permitted," the information with the fewer number of copies permitted, which is separately specified, is followed. In this case, stricter copy generation control is possible.

By performing the above processing, the broadcast receiving device 100 of this embodiment can operate properly even when two different pieces of digital copy control information are described in the content copy control descriptor.

<Content Copy Control Exception Processing 2>
As explained using Figure 7A, in the digital broadcasting system compatible with the broadcast receiving device 100 of this embodiment, due to the location information in the MPT (see Figure 7C), data acquired via a different route (IPv4, IPv6, MPEG2-TS, URL, etc.) from the data acquired via the TLV stream of the broadcast route may be included in the same package and the same event as the data acquired via the TLV stream. This section explains content protection in such a case where copy control information is included in the MPT, etc.

First, when copy control information is included in the MPT etc., data included in the same package and the same event in the location information may be controlled according to the copy control information included in the TLV stream, even if the data was obtained via a different route (IPv4, IPv6, MPEG2-TS, URL, etc.) than the data obtained via the TLV stream of the broadcast route. As described above, the copy control state of the content specified by this copy control information can be specified as "unlimited copying" (which may be divided into two types: "unlimited copying and encryption processing required when storing and outputting" and "unlimited copying and no encryption processing required when storing and outputting"), "one generation only copying", "a specified number of copies" (for example, 9 copies + 1 move is the so-called "dubbing 10"), "no copying", etc.

Here, if the data position indicated by the location information includes MPEG2-TS data transmitted in another digital broadcast signal, the MPEG2-TS data is also broadcast in association with copy control information in the other digital broadcast signal. This raises the question of how and according to which information copy control of the MPEG2-TS data should be performed (whether according to the copy control information included in the TLV/MMT stream, or according to the copy control information included in the MPEG2-TS).

In the digital broadcasting system of this embodiment, to solve this problem, the broadcast receiving device 100 can perform one of the following solutions:

<Operation example 1>
In a first operation example, when copy control information is included in the MPT etc., and data included in the same package and the same event in the location information includes MPEG2-TS data transmitted in another digital broadcast signal, the copy control state indicated by the copy control information included in the TLV stream is given priority over the copy control state indicated by the copy control information included in the MPEG2-TS.

For example, if the copy control status indicated by the copy control information included in the TLV stream is "one-generation copy permitted" and the copy control status indicated by the copy control information included in the MPEG2-TS is "a specified number of times copy permitted," then even if the data was acquired via a different route (digital broadcasting in MPEG2-TS transmission format) than the data acquired in the TLV stream, copy control may be performed on the data as "one-generation copy permitted" content. For example, if the copy control status indicated by the copy control information included in the TLV stream is "unlimited copying permitted" and the copy control status indicated by the copy control information included in the MPEG2-TS is "specified number of times copy permitted," then copy control may be performed on the data as "unlimited copying permitted" content, even if the data was acquired via a different route (digital broadcasting in MPEG2-TS transmission format) than the data acquired in the TLV stream.

In this operation, data acquired via a route other than the TLV stream can also be put into a copy state that is desired to be managed in the broadcast system supported by the broadcast receiving device 100 of this embodiment.

<Operation example 2>
In a second operation example, when copy control information is included in the MPT or the like, and data included in the same package and the same event in the location information includes MPEG2-TS data transmitted in another digital broadcast signal, the copy control state indicated by the copy control information included in the TLV stream is compared with the copy control state indicated by the copy control information included in the MPEG2-TS, and if the copy control state indicated by the copy control information included in the MPEG2-TS is stricter than the copy control state indicated by the copy control information included in the TLV stream, the MPEG2-TS data is excluded from the content to be processed when storing in storage unit 110 or the like, recording on a removable recording medium, or outputting from a digital interface.

In this operation, for data acquired via a route other than the TLV stream, duplication of copy control states on the broadcast receiving device 100 of this embodiment can be eliminated while respecting the original copy control information set in the broadcasting system that transmits the data.

In addition, if the comparison shows that the copy control status indicated by the copy control information contained in the MPEG2-TS is the same as or more lenient than the copy control status indicated by the copy control information contained in the TLV stream, copy control can be performed on the MPEG2-TS data contained in the same package and the same event in the location information as content in the copy control status indicated by the copy control information contained in the TLV stream.

In this operation, for data acquired via a route other than the TLV stream, duplication of copy control states on the broadcast receiving device 100 of this embodiment can be eliminated while respecting the original copy control information set in the broadcasting system that transmits the data.

In the above explanation, the copyright protection function of the broadcast receiving device 100 of this embodiment has been described as being performed based on the copy control information contained in the MPT. However, the table in which the copy control information is placed is not limited to the MPT. In addition to the MPT, the copy control information may be placed and transmitted in the MH-Service Description Table (MH-SDT) or MH-Event Information Table (MH-EIT) described in FIG. 6B or other tables, and the broadcast receiving device 100 may perform copyright protection processing according to these.

According to the present embodiment described above, it is possible to provide a broadcast receiver compatible with MMT digital broadcasting.

Example 2
The following describes the second embodiment of the present invention. The configuration, processing, effects, and the like of the present embodiment are the same as those of the first embodiment unless otherwise specified. Therefore, the following mainly describes the differences between the present embodiment and the first embodiment, and omits as much as possible the description of the common points to avoid duplication. The following description is given assuming that the broadcast receiving device of the present embodiment is a television receiver that supports both the MMT and MPEG2-TS media transport methods.

[Hardware configuration of broadcast receiving device]
24 is a block diagram showing an example of the internal configuration of a broadcast receiving device 800. The broadcast receiving device 800 is composed of a main control unit 801, a system bus 802, a ROM 803, a RAM 804, a storage unit 810, a LAN communication unit 821, an expansion interface unit 824, a digital interface unit 825, a first tuner/demodulation unit 831, a second tuner/demodulation unit 832, an MMT decode processing unit 841, an MPEG2-TS decode processing unit 842, a video synthesis unit 861, a monitor unit 862, a video output unit 863, an audio synthesis unit 864, a speaker unit 865, an audio output unit 866, and an operation input unit 870.

The main control unit 801, system bus 802, ROM 803, RAM 804, storage unit 810, expansion interface unit 824, digital interface unit 825, monitor unit 862, video output unit 863, speaker unit 865, audio output unit 866, operation input unit 870, etc. have the same functions as the main control unit 101, system bus 102, ROM 103, RAM 104, storage (accumulation) unit 110, expansion interface unit 124, digital interface unit 125, monitor unit 162, video output unit 163, speaker unit 165, audio output unit 166, operation input unit 170, etc. in the broadcast receiving device 100 of Example 1, and detailed explanations are omitted.

The first tuner/demodulator 831 receives the broadcast waves of a broadcast service that employs MMT as a media transport method via an antenna (not shown), and tunes (selects) the channel of the service desired by the user based on the control of the main control unit 801. Furthermore, the first tuner/demodulator 831 demodulates the received broadcast signal to obtain an MMT data string, and outputs it to the MMT decode processor 841. The second tuner/demodulator 832 receives the broadcast waves of a broadcast service that employs MPEG2-TS as a media transport method via an antenna (not shown), and tunes (selects) the channel of the service desired by the user based on the control of the main control unit 801. Furthermore, the second tuner/demodulator 832 demodulates the received broadcast signal to obtain an MPEG2-TS data string, and outputs it to the MPEG2-TS decode processor 842.

The MMT decode processing unit 841 inputs the MMT data sequence output from the first tuner/demodulation unit 831, and performs separation and decoding of the real-time presentation elements such as the video data sequence, the audio data sequence, the superimposed text data sequence, and the subtitle data sequence based on the control signal included in the MMT data sequence. The MMT decode processing unit 841 has functions equivalent to the separation unit 132, the video decoder 141, the video color gamut conversion unit 142, the audio decoder 143, the superimposed text decoder 144, the subtitle decoder 145, the subtitle synthesis unit 146, the subtitle color gamut conversion unit 147, the data decoder 151, the cache unit 152, the application control unit 153, the browser unit 154, the application color gamut conversion unit 155, the sound source unit 156, and the like in the broadcast receiving device 100 of the first embodiment. The MMT decode processing unit 841 is capable of performing the various processes described in the first embodiment. The details of the various processes are as described in the first embodiment, and therefore will not be described here.

The MPEG2-TS decode processing unit 842 inputs the MPEG2-TS data string output from the second tuner/demodulation unit 832, and performs processes such as separation and decoding of the real-time presentation elements such as the video data string, audio data string, superimposed text data string, and subtitle data string based on the control signal contained in the MPEG2-TS data string. The MPEG2-TS decode processing unit 842 has the same functions as the IRD (Integrated Receiver Decoder) unit of a conventional television receiver that receives broadcast waves from a broadcast service that uses MPEG2-TS as the media transport method, and detailed description will be omitted.

The video synthesis unit 861 inputs the video information, subtitle information, and application information output from the MMT decode processing unit 841 and the video information, subtitle information, and application information output from the MPEG2-TS decode processing unit 842, and performs processing such as selection and/or superimposition as appropriate. The video synthesis unit 861 is equipped with a video RAM (not shown), and the monitor unit 862 and the like are driven based on the video information, etc. input to the video RAM. Furthermore, the video synthesis unit 861 performs scaling processing, superimposition processing of EPG screen information, etc. as necessary based on the control of the main control unit 801. The audio synthesis unit 164 inputs the audio information output from the MMT decode processing unit 841 and the audio information output from the MPEG2-TS decode processing unit 842, and performs processing such as selection and/or mixing as appropriate.

The LAN communication unit 821 is connected to the Internet 200 via the router device 200r, and transmits and receives data to and from each server device and other communication devices on the Internet 200. It also acquires the MMT data sequence (or a part of it) and MPEG2-TS data sequence (or a part of it) of a program transmitted via a communication line, and outputs them to the MMT decoding processing unit 841 and the MPEG2-TS decoding processing unit 842 as appropriate.

[Time display on broadcast receiving device]
In the broadcast receiving device 800 of this embodiment, the current date and the current time can be displayed on the EPG screen, various setting screens, etc. The information on the current date and the current time is transmitted by MH-TOT or the like in a broadcast service that adopts MMT as a media transport method, and is transmitted by TOT (Time Offset Table) or the like provided in SI (Service Information) defined in the MPEG-2 system in a broadcast service that adopts MPEG2-TS as a media transport method. The broadcast receiving device 800 can obtain the information on the current date and the current time by referring to the MH-TOT or the TOT.

In addition, generally, when the video synthesis unit 861 mainly selects the video information etc. output from the MMT decode processing unit 841, the information relating to the current date and current time obtained from the MH-TOT is superimposed on the video information etc., and when the video synthesis unit 861 mainly selects the video information etc. output from the MPEG2-TS decode processing unit 842, the information relating to the current date and current time obtained from the TOT is superimposed on the video information etc.

However, because there are differences in encoding/decoding processes and transmission paths between broadcast services that use MMT as the media transport method and broadcast services that use MPEG2-TS as the media transport method, there is a possibility that inconsistencies may occur, particularly in the current time display, when selecting a broadcast service that uses MMT as the media transport method and when selecting a broadcast service that uses MPEG2-TS as the media transport method. For example, as shown in FIG. 25, when the screen display is switched from EPG screen 162g, which displays channel information for a broadcast service that uses MMT as the media transport method, to EPG screen 162h, which displays channel information for a broadcast service that uses MPEG2-TS as the media transport method, the current time display switches from current time display 162g1 to current time display 162h1, which may cause the user to feel a visual discomfort due to the inconsistency.

In the broadcast receiving device 800 of this embodiment, in order to prevent the user from feeling visually uncomfortable, even when the video synthesis unit 861 is primarily selecting video information, etc. output from the MMT decoding processing unit 841, the information relating to the current date and current time obtained from the TOT is controlled to be superimposed on the video information, etc. In other words, the current time information provided by a broadcast service that employs MPEG2-TS as a media transport method is controlled to be superimposed on the content of the broadcast service that employs MMT as a media transport method.

By performing the above control, the broadcast receiving device 800 of this embodiment always displays the current time information obtained by referencing the TOT when displaying the current time. Therefore, even when switching between a broadcast service that uses MMT as the media transport method and a broadcast service that uses MPEG2-TS as the media transport method, it is possible to prevent the user from feeling visual discomfort due to inconsistencies in the display of the current time.

FIG. 26A shows an example of the selection control of the current time information reference source according to the reception status of each broadcast service in the broadcast receiving device 800 of this embodiment. In the broadcast receiving device 800 of this embodiment, when a broadcast service that uses MPEG2-TS as the media transport method is available for reception, the device always refers to the TOT to acquire current time information, and only when a broadcast service that uses MPEG2-TS as the media transport method is unavailable for reception and a broadcast service that uses MMT as the media transport method is available for reception is the device controlled to refer to the MH-TOT to acquire current time information.

In addition, the same effect as described above can be obtained by controlling the content of a broadcast service that uses MMT as the media transport method to be superimposed on the current time information provided by the broadcast service that uses MPEG2-TS as the media transport method, in the opposite manner to the above control.

As described above, in either case of controlling the content of a broadcast service that employs MMT as the media transport method to be superimposed with current time information provided by a broadcast service that employs MPEG2-TS as the media transport method, or controlling the content of a broadcast service that employs MPEG2-TS as the media transport method to be superimposed with current time information provided by a broadcast service that employs MMT as the media transport method, it is possible to correct the current time information by referring to the "delta" parameter of the time information in the TMCC extension information area, as explained in [Time management of the broadcast receiving device] in Example 1.

In addition, in both cases of broadcast services that use MMT as the media transport method and broadcast services that use MPEG2-TS as the media transport method, there is a possibility that the MH-TOT or TOT transmitted by each broadcast service constituting the network may contain errors due to malfunctions in the transmitting system, transmission errors, etc. In the broadcast receiving device 800 of this embodiment, as a countermeasure against the errors in the MH-TOT or TOT, if it is determined that the MH-TOT or TOT acquired from the service being received contains an error, the device has a function to acquire the MH-TOT or TOT from another broadcast service on the same network or from an arbitrary broadcast service on another network and update the time information of the built-in clock by referring to the current time information.

Figure 26B shows an example of the process of updating current time information when a broadcast service that uses MPEG2-TS as the media transport method is being received in the broadcast receiving device 800 of this embodiment. Note that the same process as shown in the figure can be performed even when a broadcast service that uses MMT as the media transport method is being received.

When updating the time information of the built-in clock in the broadcast receiving device 800 of this embodiment, the receiving function execution unit 1102 first acquires the TOT from the MPEG2-TS data sequence of the currently being received broadcast service (broadcast service that employs MPEG2-TS as the media transport method) (S301), and then acquires the current time information by referencing the acquired TOT (S302). Next, the receiving function execution unit 1102 performs a process of comparing the current time information acquired in the process of S302 with the time information of the built-in clock.

If the result of the comparison process shows that the difference between the current time information acquired in the process of S302 and the time information of the built-in clock is within a predetermined value (for example, within 3 minutes) (S303: Yes), the reception function execution unit 1102 updates the time information of the built-in clock with the current time information acquired in the process of S302 (S306). On the other hand, if the result of the comparison process shows that the difference between the current time information acquired in the process of S302 and the time information of the built-in clock is not within a predetermined value (S303: No), or if the TOT acquired in S301 has a flag indicating that there is an error in the data, the reception function execution unit 1102 acquires a TOT from an MPEG2-TS data sequence of another broadcast service in the same network, or acquires an MH-TOT from an MMT data sequence of an arbitrary broadcast service (broadcast service that adopts MMT as a media transport method) of another network (S304), and further acquires current time information from the acquired TOT or MH-TOT (S305). The reception function execution unit 1102 can then perform the comparison process of S303 again using the current time information acquired in the process of S305.

By performing the above process, if the broadcast receiving device 800 of this embodiment determines that the MH-TOT or TOT acquired from the service being received contains an error, it is able to acquire the MH-TOT or TOT from another broadcast service on the same network, or from any broadcast service on another network, and refer to the current time information to update the time information of the built-in clock.

Note that if repeating the steps S304 to S305 during initial settings after shipping from the factory fails to obtain current time information whose difference with the time information of the built-in clock falls within a specified range, the time information of the built-in clock can be set again using the current time information obtained in the step S302. In this way, it is possible to deal with cases where there is an error in the time information of the built-in clock of the broadcast receiving device 800 of this embodiment.

[EPG display on broadcast receiving device]
Event schedule information of a broadcast service that adopts MMT as a media transport method is transmitted by MH-EIT, etc. On the other hand, event schedule information of a broadcast service that adopts MPEG2-TS as a media transport method is transmitted by EIT (Event Information Table) etc. provided in SI defined in the MPEG-2 system. Therefore, generally, when video information etc. provided by a broadcast service that adopts MMT as a media transport method is displayed, event schedule information (MH-EIT) of the broadcast service that adopts MMT can be acquired, and when video information etc. provided by a broadcast service that adopts MPEG2-TS as a media transport method is displayed, event schedule information (EIT) of the broadcast service that adopts MPEG2-TS can be acquired.

However, the broadcast receiving device 800 of this embodiment is capable of acquiring both the MH-EIT and the EIT, even when displaying video information provided by a broadcast service that employs MMT as the media transport method, or when displaying video information provided by a broadcast service that employs MPEG2-TS as the media transport method, thereby improving usability for the user.

Figure 27A shows an example of an EPG screen in the broadcast receiving device 800 of this embodiment. In the figure, EPG screen 162i is an EPG screen created based on the MH-EIT of a broadcast service that uses MMT as the media transport method, and "M1 TV", "M2 Broadcast", "M3 Channel", "M4 TV", "TV M5", etc. are the broadcast station names of the broadcast service that uses MMT as the media transport method. Also, EPG screen 162j is an EPG screen created based on the EIT of a broadcast service that uses MPEG2-TS as the media transport method, and "T6 TV", "T7 Broadcast", "T8 Channel", "T9 TV", "TV TA", etc. are the broadcast station names of the broadcast service that uses MPEG2-TS as the media transport method.

For example, when a user is watching a broadcast program provided by a broadcast service that employs MMT as the media transport method and instructs the display of an EPG screen by operating a remote control (not shown), the initial screen of the EPG screen (not shown) is displayed. The initial screen of the EPG screen is an EPG screen created based on the MH-EIT of the broadcast service that employs MMT as the media transport method, and displays detailed information about broadcast programs on each channel from 17:00 (nearby the current time) on October 7, 2014 (today). Next, if the user wishes to check detailed information about broadcast programs on each channel from 20:00 on October 9, 2014, and instructs the update of the EPG screen by operating a remote control (not shown), EPG screen 162i is displayed.

Furthermore, if the user wishes to check detailed information on a broadcast program provided by a broadcast service that employs MPEG2-TS as the media transport method and instructs a network switch by operating a remote control (not shown), an EPG screen 162j is displayed. At this time, the broadcast receiving device 800 of this embodiment controls to display detailed information on the broadcast programs of each channel on the same day and in the same time slot (i.e., from 8:00 p.m. on October 9, 2014) as the EPG screen 162i that was displayed immediately before, rather than the initial screen of the EPG screen (i.e., detailed information on the broadcast programs of each channel from 5:00 p.m. on October 7, 2014) created based on the EIT of the broadcast service that employs MPEG2-TS as the media transport method.

The above-mentioned control enables the user to continuously check detailed information about broadcast programs on the same day and at the same time on multiple networks using different media transport methods with simple operations. In other words, the usability of the broadcast receiving device 800 is improved.

Figure 27B is a diagram showing an example of an EPG screen in the broadcast receiving device 800 of this embodiment that is different from the above. EPG screen 162k shows a state in which EPG screen 162i shown in Figure 27A is displayed and then scrolled in the channel direction (horizontal direction) by operating a remote control (not shown). That is, in the example shown in Figure 27B, by scrolling the EPG screen in the channel direction (horizontal direction), channel information created based on the MH-EIT of a broadcast service that employs MMT as the media transport method and channel information created based on the EIT of a broadcast service that employs MPEG2-TS as the media transport method are seamlessly displayed on the same time axis.

Therefore, even if a user wishes to check channel information created based on the EIT of a broadcast service that employs MPEG2-TS as a media transport method while checking channel information created based on the MH-EIT of a broadcast service that employs MMT as a media transport method, it is possible to eliminate the need to instruct switching of networks by operating a remote control (not shown). Furthermore, the user can simultaneously check detailed information about broadcast programs on the same day and at the same time on multiple networks that employ different media transport methods. In other words, the usability of the broadcast receiving device 800 is improved.

Example 3
The following describes the third embodiment of the present invention. The configuration, processing, effects, and the like of the third embodiment are the same as those of the first embodiment unless otherwise specified. Therefore, the following mainly describes the differences between the first embodiment and the third embodiment, and omits as much as possible the description of the common points to avoid duplication.

The third embodiment of the present invention has a hardware configuration similar to that of the broadcast receiver 100 in the first embodiment, and performs control to realize a different copyright protection function. Note that the content protection control for video content is described in this embodiment, and for audio, the same control as described below may be performed, or different content protection control may be performed.

Figure 28 is a table summarizing the processing of the copyright protection function in the broadcast receiving device 100 of Example 3. In the broadcast receiving device 100 of Example 3, the copyright protection processing for the content before and after the content storage processing is switched depending on whether the received content is 2K or more content (content having a pixel count exceeding 1920 x 1080), such as 4K content (pixel count 3840 x 2160) or 8K content (pixel count 7680 x 4320), or 2K or less content (content having a pixel count of 1920 x 1080 or less).

Specifically, the content protection process based on the parameters included in the content copy control descriptor described in Figures 22A and 22B (e.g., the "digital_recording_control_data" parameter) and the parameters included in the content usage control descriptor described in Figure 23 (e.g., the "encryption_mode" parameter) is switched as shown in Figure 28 depending on the pixel count of the content received by the broadcast receiving device 100 or the pixel count after conversion in the case where pixel count conversion has been performed. Also, in the broadcast receiving device 100 of Example 3 of the present invention, the "image_constraint_token" parameter is essentially invalid in the content usage control descriptor shown in Figure 23. In other words, regardless of the value entered in the "image_constraint_token" parameter, the broadcast receiving device 100 of Example 3 can determine that the resolution of the video signal output is not to be restricted. In other words, the idea behind copyright protection in the broadcast receiving device 100 of Example 3 is not to limit the resolution of the video signal output to the user according to the "image_constraint_token" parameter, but to provide appropriate content protection according to the pixel count state before and after the content storage process, according to the table in Figure 28.

The table in Figure 28 uses storage processing, which is processing for recording received content in storage unit 110 in Figure 8A or the like so that it cannot be played on devices other than broadcast receiver 100, as a basis for explanation, and divides it into pre-storage processing that can be performed before storage processing and post-storage processing that is performed after storage. First, pre-storage processing will be explained. Note that in this embodiment, when the expression "before storage" of content is used, it does not necessarily mean that the content is then subjected to storage processing. It includes both the meaning of "the state before the content is actually stored" and the meaning of "without storing the content".

[Contents when received]
In the broadcast receiver 100 of the third embodiment, content in the MMT transmission method is received, and therefore all transmission methods are MMT transmission methods in the example of Fig. 28. Here, the content at the time of receiving the content may be 4K content (3840 x 2160 pixels) or 8K content (7680 x 4320 pixels), or may be over 2K content (content having a pixel count exceeding 1920 x 1080 pixels), or may be 2K or less content (content having a pixel count of 1920 x 1080 or less).

The broadcast receiver 100 can use data transmitted by the MMT method to determine whether the received content is 2K or above content or 2K or below content. Specifically, it can use pixel count information included in the header of the content's video encoding stream (e.g., H.265/HEVC encoded stream), or it can use pixel count information stored in "video_resolution" included in the video component descriptor of FIG. 19A described in Example 1. The determination can be made using either data transmitted by the MMT method.

[Pixel conversion process after receiving content and before storing]
The broadcast receiver 100 of the third embodiment has a pixel number conversion unit (not shown) that converts the number of pixels of the image either before or after the image synthesis unit of FIG. 8A, and is capable of performing pixel number conversion processing of the decoded image of the received content. As shown in the table of FIG. 28, there are cases where pixel number conversion is not performed on the received over 2K content (content having a pixel number exceeding 1920×1080), pixel number conversion is performed to convert it into another over 2K content, and pixel number conversion is performed to convert it into 2K or less content (content having a pixel number of 1920×1080 or less). Also, as shown in the table of FIG. 28, there are cases where pixel number conversion is not performed on the received under 2K content (content having a pixel number of 1920×1080 or less) and pixel number conversion is performed to convert it into another under 2K content (content having a pixel number of 1920×1080 or less).

[Processing of output to external device after receiving content and before storing]
In the broadcast receiver 100 of the third embodiment, when the content is received and the content before storage is output to an external device, the content protection process is switched according to the state of the pixel count of the content. Specifically, the content protection process is changed according to whether the pixel count of the content when the content is output to an external device after the content is received and before storage is a pixel count exceeding 1920×1080 or a pixel count of 1920×1080 or less. Here, changing the content protection process means changing the interpretation of the parameters included in the content copy control descriptor described in FIG. 22A and FIG. 22B (e.g., the “digital_recording_control_data” parameter) and the parameters included in the content usage control descriptor described in FIG. 23 (e.g., the “encryption_mode” parameter), and switching the content protection process performed on these parameters.

A specific example of the output process to an external device after receiving the content and before storing it as shown in FIG. 28 will be described below. The output process to an external device may be applied to the video output process when the video decoded by the video decoder 141 in FIG. 8A or the video converted from the decoded video by the pixel count conversion unit is output from the video output unit 163 to an external device. As another example, the video output may be performed via an IP interface in which the LAN communication unit 121 in FIG. 8A is hardware.

(1-1) When receiving and outputting 2K+ content (content with a pixel count exceeding 1920 x 1080) to an external device without pixel count conversion, or when converting the pixel count and outputting 2K+ content with a different pixel count (content with a pixel count exceeding 1920 x 1080) to an external device

In this case, the value of "encryption_mode" in the content usage control descriptor is not taken into consideration when protecting the content output. If "digital_recording_control_data" in the content copy control descriptor is 00, the content is output without HDCP content protection. If "digital_recording_control_data" in the content copy control descriptor is 10, the content is output with the advanced content protection of HDCP Revision 2.2 or later applied. If "digital_recording_control_data" in the content copy control descriptor is 01, output itself is prohibited. If "digital_recording_control_data" in the content copy control descriptor is 11, the content is output with the advanced content protection of HDCP Revision 2.2 or later applied. If the content copy control descriptor for the received content is not included in the received data for some reason, the content will be output without HDCP content protection.

The content protection process that interprets the "digital_recording_control_data" parameter included in the content copy control descriptor and the "encryption_mode" parameter included in the content usage control descriptor as described above when outputting to an external device before storage is hereafter referred to as "super 2K content protection process" when outputting to an external device before storage.

(1-2) When receiving content that is over 2K (content with a pixel count exceeding 1920 x 1080) and the pixel count is converted to 2K or less (content with a pixel count of 1920 x 1080 or less) and output to an external device

If the "digital_recording_control_data" of the content copy control descriptor is 00 or if the content copy control descriptor of the received content is not included in the received data for some reason, the content protection at the time of output is switched on or off depending on the value of the "encryption_mode" of the content usage control descriptor. At this time, if the "encryption_mode" value of the content usage control descriptor is 1 and content protection is not specified, the content can be output without protection by HDCP. If the "encryption_mode" value of the content usage control descriptor is 0 and content protection is specified, the content is output with protection by HDCP Revision 1 or Revision 2 or later.

Also, if "digital_recording_control_data" in the content copy control descriptor is 10, the data is output with protection according to HDCP Revision 1 or Revision 2 or later, regardless of the value of "encryption_mode" in the content usage control descriptor. If "digital_recording_control_data" in the content copy control descriptor is 01, output itself is prohibited, regardless of the value of "encryption_mode" in the content usage control descriptor. If "digital_recording_control_data" in the content copy control descriptor is 11, the data is output with protection according to HDCP Revision 1 or Revision 2 or later, regardless of the value of "encryption_mode" in the content usage control descriptor. If the content copy control descriptor for the received content is not included in the received data for some reason, the content will be output without HDCP content protection.

The content protection process that interprets the "digital_recording_control_data" parameter included in the content copy control descriptor and the "encryption_mode" parameter included in the content usage control descriptor as described above when outputting to an external device before storage is hereafter referred to as "2K or less content protection process" when outputting to an external device before storage.

(1-3) When receiving 2K or less content (content with a pixel count of 1920 x 1080 or less) and outputting it to an external device without pixel count conversion, or when converting the pixel count and converting it to another 2K or less content (content with a pixel count of 1920 x 1080 or less) and outputting it to an external device

In this case, the "2K or less content protection process" described in (1-2) is performed when outputting to an external device before storage.

As explained above in (1-1), (1-2), and (1-3), when outputting to an external device before accumulation, the interpretation of the "digital_recording_control_data" parameter included in the content copy control descriptor and the "encryption_mode" parameter included in the content usage control descriptor is switched depending on the pixel count of the content when outputting to the external device before accumulation, and when outputting to an external device in the form of copy-restricted 2K or more content (content with a pixel count of 1920 x 1080 or less), the content is output with a higher level of content protection than when outputting to an external device in the form of copy-restricted 2K or less content (content with a pixel count of 1920 x 1080 or less). This allows for more added-value 2K or more content (content with a pixel count of more than 1920 x 1080) to be appropriately protected even in external devices.

[Content protection processing during content storage]
As already explained, in the broadcast receiver 100 of the third embodiment, in the output process to an external device after receiving the content and before storing it, the content protection process is switched according to the pixel count state of the content. This is because the playback device that plays the content at the output destination is an external device, and the support level of the content protection process may differ depending on the device.

In contrast, when storing content using a content storage function that can only be played back by the broadcast receiver 100 that received and recorded the content, there is no need to change the processing depending on the pixel count of the content. This is because the content is managed only by the broadcast receiver 100 itself, so there is no need to consider multiple levels of content protection processing. Therefore, in order to simplify management within the broadcast receiver 100, when storing content using a content storage function that can only be played back by the broadcast receiver 100 that received and recorded the content, it is desirable to perform a common storage protection process whether the content is over 2K content (content with a pixel count exceeding 1920 x 1080) or 2K or less content (content with a pixel count of 1920 x 1080 or less) at the time of storage. Note that the content storage process may be performed, for example, on the storage unit 110 (FIG. 8A), which is a recording medium built into the broadcast receiver 100 of the third embodiment. However, if a local encryption process specific to the broadcast receiver 100 is performed and management is performed so that only the broadcast receiver 100 can play the content, storage may be performed on a recording medium such as an external hard disk.

In the content accumulation process shown in FIG. 28, the following content is stored: content that has not undergone pixel count conversion for content that is over 2K (content having a pixel count exceeding 1920 x 1080) at the time of reception; content that has undergone pixel count conversion for content that is over 2K (content having a pixel count exceeding 1920 x 1080) at the time of reception and has been converted to over 2K content (content having a pixel count exceeding 1920 x 1080) with a different pixel count (content having a pixel count exceeding 1920 x 1080); The following common storage protection process is performed for all of the following content types: content that has been converted to 2K or less content (content with a pixel count of 1920 x 1080 or less) by pixel count conversion when received, content that has not been converted to 2K or less content (content with a pixel count of 1920 x 1080 or less) by pixel count conversion when received, and content that has been converted to other 2K or less content (content with a pixel count of 1920 x 1080 or less) by pixel count conversion when received.

Here, "common storage protection processing" means that the interpretation processing of the "digital_recording_control_data" parameter included in the content copy control descriptor, the "encryption_mode" parameter included in the content usage control descriptor, and other parameters is common between over 2K content (content with a pixel count exceeding 1920 x 1080) and 2K or less content (content with a pixel count of 1920 x 1080 or less) at the time of storage.

Below, we will explain a specific example of the "common storage protection process" of the content storage process shown in Figure 28.

First, if the value of the "digital_recording_control_data" parameter included in the content copy control descriptor is 00, meaning "copying permitted without restrictions," content can be stored without copy restrictions. Copy control information on the recording medium at the time of storage that manages the content stored on the recording medium may be stored as "copying permitted without restrictions." Note that the copy control information on the recording medium used to control copying of the stored content may be generated and managed separately from the value of the "digital_recording_control_data" parameter included in the content copy control descriptor, and there is no need to rewrite the value of the "digital_recording_control_data" parameter included in the content copy control descriptor.

In this case, the value of the "encryption_mode" parameter included in the content usage control descriptor is taken into consideration. If this value is 1 and content protection is specified, then when the storage process is performed, local encryption processing specific to the broadcast receiver 100 is applied and the content is stored so that it can only be played on the broadcast receiver 100. If the value of the "encryption_mode" parameter included in the content usage control descriptor is 0 and content protection is not specified, then the local encryption processing does not need to be performed (however, in this case, local encryption processing may be applied). While the content is being stored as "Copyable without restrictions", a common content protection process is performed without changing the content protection process according to the number of pixels of the content until the external device output, external device copy, or external device move described below is performed. This makes it possible to simplify management within the broadcast receiver 100.

If the value of the "digital_recording_control_data" parameter included in the content copy control descriptor is 10 and the "copy_restriction_mode" parameter (see FIG. 23) included in the content usage control descriptor is 1, the content is interpreted as "copyable for one generation only", and in the storage process, the copy control information on the recording medium at the time of storage that manages the content stored on the recording medium is stored as "no re-copying". Note that the copy control information on the recording medium used for copy control of the stored content may be generated and managed separately from the value of the "digital_recording_control_data" parameter included in the content copy control descriptor, and there is no need to rewrite the value of the "digital_recording_control_data" parameter included in the content copy control descriptor. Note that when performing storage processing as "no re-copying", the content is stored after undergoing local encryption processing specific to the broadcast receiver 100 so that it can only be played on the broadcast receiver 100. Content that is being stored with "no more copying allowed" is prohibited from being copied. While the content is being stored with "no more copying allowed", and before it is output to an external device or moved to an external device with "no more copying allowed", as described below, the content protection process remains the same depending on the number of pixels in the content, and a common content protection process is performed. This simplifies management within the broadcast receiver 100.

When the value of the "digital_recording_control_data" parameter included in the content copy control descriptor is 10 and the "copy_restriction_mode" parameter included in the content usage control descriptor is 0, the content is interpreted as "number-limited copying allowed", and in the storage process, the copy control information on the recording medium at the time of storage that manages the content stored on the recording medium can be stored as "number-limited copying allowed". Note that the copy control information on the recording medium used for copy control of the stored content may be generated and managed separately from the value of the "digital_recording_control_data" parameter included in the content copy control descriptor, and there is no need to rewrite the value of the "digital_recording_control_data" parameter included in the content copy control descriptor. Note that when performing storage processing as "number-limited copying allowed", the content is stored after undergoing local encryption processing specific to the broadcast receiver 100 so that it can only be played on the broadcast receiver 100. While the content is being stored as "limited number of copies allowed," the same content protection process is performed according to the number of pixels of the content until the content is output to an external device, copied to an external device, or moved to an external device as described below as "no further copying allowed." This simplifies management within the broadcast receiver 100.

If the value of the "digital_recording_control_data" parameter included in the content copy control descriptor is 11, it is interpreted as "copy prohibited" content. In this case, if the broadcast receiver 100 supports the "temporary storage" function, temporary storage is possible, but if the broadcast receiver 100 does not support the "temporary storage" function, storage is prohibited and storage processing is not performed. If the broadcast receiver 100 supports the "temporary storage" function, in the storage processing, the copy control information on the recording medium at the time of storage that manages the content to be stored on the recording medium is stored as "temporary storage", and storage of the content for a certain period of time (for example, 1 hour and 30 minutes) is possible. In this case, the storage time is managed in 1-minute units, and the stored content must be made unplayable before it exceeds the above-mentioned certain period of time + 1 minute from the time of reception (= the start of storage). Specific examples of making content unplayable include erasing the content itself or erasing the encryption key, which makes it impossible to play the content. Content being stored as "temporary storage" is prohibited from being copied or moved. While the content is being stored as "no further copying", the content protection process remains the same depending on the number of pixels of the content until it is output to an external device as "no further copying", as described below. This simplifies management within the broadcast receiver 100.

As explained above, when storing content, the interpretation of the "digital_recording_control_data" parameter included in the content copy control descriptor and the "encryption_mode" parameter included in the content usage control descriptor is not switched depending on the number of pixels of the content at the time of storage, and the content protection process is standardized. This makes it possible to simplify management within the broadcast receiver 100.

[Pixel conversion process after content storage]
The broadcast receiver 100 of Example 3 has a pixel number conversion unit (not shown) that converts the number of pixels of the video either before or after the video synthesis unit of Figure 8A, and has a pixel number conversion unit (not shown) that plays back the stored content from the storage unit 110 of Figure 8A, decodes the video data with the video decoder 141, and converts the number of pixels of the video, making it possible to perform pixel number conversion processing of the decoded video of the content stored in the storage unit 110.

As shown in the table of FIG. 28, there are cases where pixel count conversion is not performed on received ultra-2K content (content having a pixel count exceeding 1920 x 1080) that is stored without pixel count conversion, or pixel count conversion is performed on received ultra-2K content (content having a pixel count exceeding 1920 x 1080) that is converted to other ultra-2K content (content having a pixel count exceeding 1920 x 1080) and stored, when the content is output, moved, or copied after storage. In this case, the content to be output, moved, or copied is ultra-2K content (content having a pixel count exceeding 1920 x 1080).

In addition, there are cases where the received ultra 2K content (content having a pixel count exceeding 1920 x 1080) is stored without pixel count conversion, or the received ultra 2K content (content having a pixel count exceeding 1920 x 1080) is converted into another ultra 2K content (content having a pixel count exceeding 1920 x 1080) and stored after pixel count conversion is performed, and then pixel count conversion is performed when outputting, moving, or copying the ultra 2K content (content having a pixel count exceeding 1920 x 1080) after storage to convert it into another ultra 2K content. In this case, the content to be output, moved, or copied is ultra 2K content (content having a pixel count exceeding 1920 x 1080).

In addition, when receiving ultra-2K content (content having a pixel count exceeding 1920 x 1080) and storing it without pixel count conversion, or when receiving ultra-2K content (content having a pixel count exceeding 1920 x 1080) and converting it into other ultra-2K content (content having a pixel count exceeding 1920 x 1080) and storing it by converting the pixel count, the pixel count may be converted to 2K or less content (content having a pixel count of 1920 x 1080 or less) when outputting, moving, or copying it after storage. In this case, the content to be output, moved, or copied is 2K or less content (content having a pixel count of 1920 x 1080 or less).

In addition, pixel count conversion may be performed on received over 2K content (content with a pixel count exceeding 1920 x 1080) to convert it to 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, but pixel count conversion may not be performed on the 2K or less content (content with a pixel count of 1920 x 1080 or less) when it is output, moved, or copied after storage. In this case, the content to be output, moved, or copied is 2K or less content (content with a pixel count of 1920 x 1080 or less).

In addition, pixel count conversion may be performed on received over 2K content (content with a pixel count exceeding 1920 x 1080) to convert it to 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, and the pixel count may then be converted when the stored 2K or less content (content with a pixel count of 1920 x 1080 or less) is output, moved, or copied to another 2K or less content (content with a pixel count of 1920 x 1080 or less). In this case, the content to be output, moved, or copied is 2K or less content (content with a pixel count of 1920 x 1080 or less).

In addition, there are cases where pixel count conversion is not performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is stored without pixel count conversion, or pixel count conversion is performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is converted into other 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, when the content is output, moved, or copied after storage. In this case, the content to be output, moved, or copied is 2K or less content (content with a pixel count of 1920 x 1080 or less).

In addition, there are cases where 2K or less content (content with a pixel count of 1920 x 1080 or less) received is stored without pixel count conversion (content with a pixel count of 1920 x 1080 or less), or where pixel count conversion is performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) converted to other 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, and then pixel count conversion is performed on the 2K or less content (content with a pixel count of 1920 x 1080 or less) that has been output, moved, or copied after storage to convert it to other 2K or less content (content with a pixel count of 1920 x 1080 or less). In this case, the content to be output, moved, or copied is 2K or less content (content with a pixel count of 1920 x 1080 or less).

[Output process to external device after content storage]
As already explained, in the broadcast receiver 100 of the third embodiment, in the content storage process, the content protection process is not switched depending on the pixel count of the content, but a common content protection process is performed. This is because, when the content is stored using a content storage function that allows only the broadcast receiver 100 that received and recorded the content to play back, the content is managed only by the broadcast receiver 100 itself, so there is no need to consider multiple support levels for the content protection process. On the other hand, when the stored content is output to an external device, the support level for the content protection process may differ depending on the playback device that plays back the content at the output destination. Therefore, it is desirable to change the content protection process depending on the pixel count of the content when the stored content is output to an external device.

A specific example of the output process to an external device after content storage shown in FIG. 28 will be described below. The output process to an external device after content storage may be applied to a video output process when the video of the content stored in the storage unit 110 in FIG. 8A is decoded by the video decoder 141, or the decoded video is converted by the pixel count conversion unit, and output to an external device from the video output unit 163. As another example, the video output may be performed via an IP interface in which the LAN communication unit 121 in FIG. 8A is hardware.

(2-1) When pixel count conversion is not performed on received ultra 2K content (content with a pixel count exceeding 1920 x 1080) that has been stored without pixel count conversion, or when pixel count conversion is performed on received ultra 2K content (content with a pixel count exceeding 1920 x 1080) that has been converted to other ultra 2K content (content with a pixel count exceeding 1920 x 1080) and stored, pixel count conversion is not performed when outputting to an external device after storage.

In this case, the content to be output externally is over 2K content (content with a pixel count exceeding 1920 x 1080).

For content that has copy control information on the recording medium set as "copyable without restrictions" at the time of storage, when the content is played back and output externally after storage, it can be output without content protection using HDCP. In this case, it is not taken into consideration whether protection was specified or not based on the value of the "encryption_mode" parameter included in the content usage control descriptor at the time of storage. This makes it possible to standardize the processing for external output of content before storage with the case where "digital_recording_control_data" of the content copy control descriptor in (1-1) above is 00.

For content that has copy control information stored on the recording medium as "no further copying", content that has copy control information stored on the recording medium as "limited number of copies allowed", and content that has copy control information stored on the recording medium as "temporary storage", when played back and output externally after storage, the content will be output applying advanced content protection of HDCP Revision 2.2 or later.

When the accumulated content is output to an external device as over 2K content (content with a pixel count exceeding 1920 x 1080), the content protection process that protects the content as described above in accordance with the copy control information on the recording medium is hereafter referred to as "over 2K content protection process" when outputting to an external device after accumulation.

(2-2) When 2K content (content with a pixel count exceeding 1920 x 1080) received is stored without pixel count conversion, or when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to another 2K content (content with a pixel count exceeding 1920 x 1080) by pixel count conversion and stored, and then pixel count conversion is performed when outputting to an external device after storage to convert the content to another 2K content.

In this case, the content to be output externally is 2K content (content with a pixel count exceeding 1920 x 1080), which is the same as in (2-1) above, so the "2K content protection process" described in (2-1) above is performed when outputting to an external device after storage.

(2-3) When 2K content (content with a pixel count exceeding 1920 x 1080) received is stored without pixel count conversion, or when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to other 2K content (content with a pixel count exceeding 1920 x 1080) by pixel count conversion and stored, and when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to other 2K content (content with a pixel count exceeding 1920 x 1080) by pixel count conversion when outputting to an external device after storage, it is converted to 2K or less content (content with a pixel count of 1920 x 1080 or less)

In this case, the content to be output externally is 2K or less content (content with a pixel count of 1920 x 1080 or less).

In this case, for content that has copy control information on the recording medium set as "copyable without restrictions" at the time of storage, the content protection process is switched taking into consideration whether protection was specified or not, depending on the value of the "encryption_mode" parameter included in the content usage control descriptor at the time of storage. Specifically, if the value of "encryption_mode" is 1 and content protection is not specified, the content can be output without HDCP content protection when played back and output to an external device after storage. If the value of "encryption_mode" is 0 and content protection is specified, the content is output with protection using HDCP Revision 1 or Revision 2 or later when played back and output to an external device after storage. This allows the process to be the same as when "digital_recording_control_data" of the content copy control descriptor in (1-2) above is 00 for external output of content before storage.

In addition, for content that has copy control information stored on the recording medium as "no further copying", content that has copy control information stored on the recording medium as "limited number of copies allowed", and content that has copy control information stored on the recording medium as "temporary storage", the content will be protected using HDCP Revision 1 or Revision 2 or later before being output.

When the accumulated content is output to an external device as 2K or less content (content with a pixel count of 1920 x 1080 or less), the content protection process that protects the content as described above in accordance with the copy control information on the recording medium is hereafter referred to as "2K or less content protection process" when outputting to an external device after accumulation.

(2-4) When pixel count conversion is performed on received over 2K content (content with a pixel count exceeding 1920 x 1080) to convert it to 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, pixel count conversion is not performed on the 2K or less content (content with a pixel count of 1920 x 1080 or less) when outputting to an external device after storage.

In this case, the content to be output externally is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (2-3) above, so the "2K or less content protection process" described in (2-3) is performed when outputting to an external device after storage.

(2-5) When receiving over 2K content (content with a pixel count exceeding 1920 x 1080) and converting it to 2K or less content (content with a pixel count of 1920 x 1080 or less) by pixel count conversion, and storing the 2K or less content (content with a pixel count of 1920 x 1080 or less), the pixel count is converted when outputting to an external device after storage to convert it to another 2K or less content (content with a pixel count of 1920 x 1080 or less)

In this case, the content to be output externally is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (2-3) above, so the "2K or less content protection process" described in (2-3) is performed when outputting to an external device after storage.

(2-6) When pixel count conversion is not performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is stored without pixel count conversion, or when pixel count conversion is performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is converted to other 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, and pixel count conversion is not performed on the external device output after storage.

In this case, the content to be output externally is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (2-3) above, so the "2K or less content protection process" described in (2-3) is performed when outputting to an external device after storage.

(2-7) When the received 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less) without pixel count conversion, or when the received 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less) after pixel count conversion and output to an external device after storage

In this case, the content to be output externally is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (2-3) above, so the "2K or less content protection process" described in (2-3) is performed when outputting to an external device after storage.

As explained above in (2-1) to (2-7), when storing and outputting to an external device, content protection processing is switched according to the pixel count of the content when outputting to the external device after storage. When outputting to an external device in the form of copy-restricted over 2K content (content with a pixel count exceeding 1920 x 1080), the content is output with a higher level of content protection than when outputting to an external device in the form of copy-restricted under 2K content (content with a pixel count of 1920 x 1080 or less). This allows for more added-value over 2K content (content with a pixel count exceeding 1920 x 1080) to be appropriately protected even in external devices.

[Moving content to external devices after storage]
As already explained, in the broadcast receiver 100 of the third embodiment, in the content storage process, the content protection process is not switched depending on the pixel count of the content, but a common content protection process is performed. This is because, when the content is stored using a content storage function that allows only the broadcast receiver 100 that received and recorded the content to play back, the content is managed only by the broadcast receiver 100 itself, so there is no need to consider multiple support levels for the content protection process. On the other hand, when the stored content is moved to an external device, the support level for the content protection process may differ depending on the device to which the content is moved. Therefore, it is desirable to change the content protection process depending on the pixel count of the content when the stored content is moved to an external device.

A specific example of the process of moving content to an external device after it has been stored as shown in FIG. 28 will be described below. Note that the process of moving content to an external device after it has been stored in the storage unit 110 in FIG. 8A may be performed, for example, via an IP interface that uses the LAN communication unit 121 in FIG. 8A as hardware.

(3-1) When pixel count conversion is not performed on received ultra 2K content (content with a pixel count exceeding 1920 x 1080) that has been stored without pixel count conversion, or when pixel count conversion is performed on received ultra 2K content (content with a pixel count exceeding 1920 x 1080) that has been converted to other ultra 2K content (content with a pixel count exceeding 1920 x 1080) and stored, pixel count conversion is not performed when moving to an external device after storage.

In this case, the content to be moved to the external device is over 2K content (content with a pixel count exceeding 1920 x 1080).

For content that has copy control information on the recording medium set as "Copy allowed without restrictions" at the time of storage, when the content is moved to an external device after storage, it can be moved without content protection using DTCP. In this case, it does not take into account whether or not protection was specified based on the value of the "encryption_mode" parameter included in the content usage control descriptor at the time of storage.

For content that has copy control information on the recording medium set as "no further copying" when it was stored, or content that has copy control information on the recording medium set as "limited number of copies allowed" when it was stored, the content can be protected by DTCP2 (described in Reference 1), a more advanced content protection system than DTCP-IP, and then moved to an external device. Note that even if an external device supports content protection by DTCP-IP, if it does not support content protection by DPCT2, it cannot play content protected by DTCP2 (content protected by DTCP2 cannot be sent). Thus, while DPCT2 provides stronger content protection, existing external devices cannot handle content protected by DTCP2. In contrast, content protection by DTCP-IP cannot use the new content protection flags of DPCT2, but it does allow moving to existing DTCP-IP-compatible external devices that do not support DPCT2.

[Reference 1: Digital Transmission Licensing Administrator DTCP2 Presentation to CPTWG January 27, 2016]

When the stored content is moved to an external device as ultra-2K content (content with a pixel count exceeding 1920 x 1080), the content protection process that protects the content as described above in accordance with the copy control information on the recording medium is hereafter referred to as "ultra-2K content protection process" when moving to an external device after storage.

(3-2) When 2K content (content with a pixel count exceeding 1920 x 1080) received is stored without pixel count conversion, or when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to another 2K content (content with a pixel count exceeding 1920 x 1080) by pixel count conversion and stored, and when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to another 2K content by pixel count conversion when moved to an external device after storage.

In this case, the content to be moved to the external device is over 2K content (content with a pixel count exceeding 1920 x 1080), which is the same as in (3-1) above, so the "over 2K content protection process" described in (3-1) is carried out when moving to the external device after storage.

(3-3) When 2K content (content with a pixel count exceeding 1920 x 1080) received is stored without pixel count conversion, or when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to other 2K content (content with a pixel count exceeding 1920 x 1080) and stored, pixel count conversion is performed on the 2K content (content with a pixel count exceeding 1920 x 1080) when it is moved to an external device after storage and converted to 2K or less content (content with a pixel count of 1920 x 1080 or less)

In this case, the content to be moved to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less).

In this case, for content that has copy control information on the recording medium set as "copyable without restrictions" at the time of storage, content protection processing is switched taking into consideration whether or not protection was specified, depending on the value of the "encryption_mode" parameter included in the content usage control descriptor at the time of storage. Specifically, if the value of "encryption_mode" is 1 and content protection is not specified, content can be moved without DTCP content protection when moved to an external device after storage. If the value of "encryption_mode" is 0 and content protection is specified, content can be moved with DTCP protection (DTCP-IP when moving via an IP interface) when moved to an external device after storage. In this case, content protection with DTCP2 is not required.

In addition, for content that has copy control information stored on the recording medium as "no further copying allowed" or content that has copy control information stored on the recording medium as "limited number of copies allowed", the content will be moved after being protected by DTCP (or DTCP-IP if moved via an IP interface). In this case, content protection by DTCP2 is not required.

When the stored content is moved to an external device as 2K or less content (content with a pixel count of 1920 x 1080 or less), the content protection process that protects the content as described above in accordance with the copy control information on the recording medium is hereafter referred to as "2K or less content protection process" when moving to an external device after storage.

(3-4) When pixel count conversion is performed on received over 2K content (content with a pixel count exceeding 1920 x 1080) to convert it to 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, pixel count conversion is not performed on the 2K or less content (content with a pixel count of 1920 x 1080 or less) when it is moved to an external device after storage.

In this case, the content to be moved to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (3-3) above, so the "2K or less content protection process" described in (3-3) is performed when moving to the external device after storage.

(3-5) When receiving over 2K content (content with a pixel count exceeding 1920 x 1080) and converting it to 2K or less content (content with a pixel count of 1920 x 1080 or less) by converting the pixel count, and storing the 2K or less content (content with a pixel count of 1920 x 1080 or less), when moving the stored 2K or less content to an external device, the pixel count is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less)

In this case, the content to be moved to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (3-3) above, so the "2K or less content protection process" described in (3-3) is performed when moving to the external device after storage.

(3-6) When pixel count conversion is not performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is stored without pixel count conversion, or when pixel count conversion is performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is converted to other 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, and pixel count conversion is not performed when the content is moved to an external device after storage.

In this case, the content to be moved to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (3-3) above, so the "2K or less content protection process" described in (3-3) is performed when moving to the external device after storage.

(3-7) When the received 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted into another 2K or less content (content with a pixel count of 1920 x 1080 or less) without pixel count conversion, or when the received 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted into another 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted into another 2K or less content (content with a pixel count of 1920 x 1080 or less) after pixel count conversion and moved to an external device after storage, pixel count conversion is performed.

In this case, the content to be moved to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (3-3) above, so the "2K or less content protection process" described in (3-3) is performed when moving to the external device after storage.

As explained above in (3-1) to (3-7), when moving stored content to an external device, content protection processing is switched depending on the pixel count of the content when moving to an external device after storage. When moving copy-restricted 2K+ content (content with a pixel count exceeding 1920 x 1080) to an external device, the content is moved with a higher level of content protection than when moving copy-restricted 2K or less content (content with a pixel count of 1920 x 1080 or less) to an external device. This allows higher-added-value 2K+ content (content with a pixel count exceeding 1920 x 1080) to be appropriately protected even on external devices.

In any of the above cases (3-1) to (3-7), moving content to an external device involves a series of processes in which the content is copied to only one authenticated external device and the original content is rendered unplayable. In this case, the original content must be rendered unplayable within one minute after the content is copied to the external device. Specific examples of rendering content unplayable include erasing the content itself or the encryption key, which will make it impossible to play the content.

[Copying to external devices after storing content]
As already explained, in the broadcast receiver 100 of the third embodiment, in the content storage process, the content protection process is not switched depending on the pixel count of the content, but a common content protection process is performed. This is because, when the content is stored using a content storage function that allows only the broadcast receiver 100 that received and recorded the content to play back, the content is managed only by the broadcast receiver 100 itself, so there is no need to consider multiple support levels for the content protection process. On the other hand, when the stored content is copied to an external device, the support level for the content protection process may differ depending on the copy destination device. Therefore, it is desirable to change the content protection process depending on the pixel count of the content when copying the stored content to an external device.

A specific example of the process of copying content to an external device after the content is stored as shown in FIG. 28 will be described below. Note that the process of copying content to an external device after the content is stored in the storage unit 110 in FIG. 8A may be performed, for example, via an IP interface that uses the LAN communication unit 121 in FIG. 8A as hardware.

In addition, for content that has copy control information on the recording medium at the time of storage set as "no re-copying", copying to an external device is prohibited. For content that has copy control information on the recording medium at the time of storage set as "limited number of copies allowed", up to nine copies can be generated in addition to the original content. However, for example, in a case where the storage unit 110 in FIG. 8A that stores the content is configured as a RAID system that performs backup processing that cannot be directly accessed by the user, the copies for backup purposes that cannot be directly accessed by the user may be excluded from the above-mentioned nine-copy limit. When copying within the nine-copy limit to an external device via an IP interface, it is necessary to perform copying in a state where the number, such as one per authenticated external device, is managed. The original content after the generation of the above-mentioned number-limited (nine) copies can be moved to an external device by the above-mentioned move process. The nine-copy process and the move process of one original content are equivalent to generating nine copies in the broadcast receiver 100 when the content is stored, and moving 10 contents, including the original content, one by one to an external device.

Below, we explain the specific process for changing the content protection process depending on the pixel count of the content when copying stored content to an external device.

(4-1) When pixel count conversion is not performed on received ultra 2K content (content with a pixel count exceeding 1920 x 1080) that has been stored without pixel count conversion, or when pixel count conversion is performed on received ultra 2K content (content with a pixel count exceeding 1920 x 1080) that has been converted to other ultra 2K content (content with a pixel count exceeding 1920 x 1080) and stored, pixel count conversion is not performed when copying to an external device after storage.

In this case, the content to be copied to the external device is over 2K content (content with a pixel count exceeding 1920 x 1080).

For content that has copy control information on the recording medium set as "Copyable without restrictions" at the time of storage, the content can be copied to an external device after storage without content protection using DTCP. In this case, it does not matter whether protection was specified or not based on the value of the "encryption_mode" parameter included in the content usage control descriptor at the time of storage.

Contents stored on the recording medium with the copy control information set to "No further copying" are prohibited from being copied to an external device. When copying contents stored on the recording medium with the copy control information set to "Limited number of copies allowed" to an external device within the above-mentioned nine-copy limit, the contents can be protected by the above-mentioned DTCP2, which is a more advanced content protection system than DTCP-IP, and copied to the external device (in this case, copying with the number of contents managed can be achieved by sending each of the contents to be copied to the external device using the move process of DTCP2. In this case, since the move process is performed for one content within the nine-copy limit, the number of contents to be copied is reduced and the content is treated as being unplayable, but it is not necessary to make the original content outside the nine-copy limit unplayable). Note that even if an external device supports content protection by DTCP-IP, if it does not support content protection by DTCP-IP, it cannot play back the content protected by DTCP2 (it cannot receive content protected by DTCP2). Therefore, although DPCT2 provides stronger content protection, existing external devices cannot handle content protected by DTCP2. In contrast, content protection using DTCP-IP cannot use the new content protection flags of DPCT2, but it does allow copying to existing DTCP-IP-compatible external devices that are not DPCT2-compatible.

When the stored content is copied to an external device as over 2K content (content with a pixel count exceeding 1920 x 1080), the content protection process that protects the content as described above in accordance with the copy control information on the recording medium is hereafter referred to as "over 2K content protection process" when copying to an external device after storage.

(4-2) When 2K content (content with a pixel count exceeding 1920 x 1080) received is stored without pixel count conversion, or when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to another 2K content (content with a pixel count exceeding 1920 x 1080) by pixel count conversion and stored, and then pixel count conversion is performed when copying to an external device after storage to convert the content to another 2K content.

In this case, the content to be copied to the external device is over 2K content (content with a pixel count exceeding 1920 x 1080), which is the same as in (4-1) above, so the "over 2K content protection process" described in (4-1) is performed when copying to the external device after storage.

(4-3) When 2K content (content with a pixel count exceeding 1920 x 1080) received is stored without pixel count conversion, or when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to other 2K content (content with a pixel count exceeding 1920 x 1080) by pixel count conversion and stored, and when 2K content (content with a pixel count exceeding 1920 x 1080) received is converted to 2K or less content (content with a pixel count of 1920 x 1080 or less) by pixel count conversion when copied to an external device after storage.

In this case, the content to be copied to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less).

In this case, for content that has copy control information on the recording medium set as "copyable without restrictions" at the time of storage, content protection processing is switched taking into consideration whether protection was specified or not, depending on the value of the "encryption_mode" parameter included in the content usage control descriptor at the time of storage. Specifically, if the value of "encryption_mode" is 1 and content protection is not specified, content can be copied without DTCP content protection when copied to an external device after storage. If the value of "encryption_mode" is 0 and content protection is specified, content can be copied with DTCP protection (DTCP-IP when copying via an IP interface) when copied to an external device after storage. In this case, content protection with DTCP2 is not required.

Content that has copy control information on the recording medium set as "no further copying" when stored is prohibited from being copied to an external device. When copying content that has copy control information on the recording medium set as "limited number of copies allowed" to an external device within the above-mentioned limit of nine, the content is protected by DTCP (DTCP-IP when copying via an IP interface). In this case, content protection by DTCP2 is not required. In order to achieve copying that manages the number of contents, the DTCP move function may be used when copying each piece of content. In this case, the move process is performed on one piece of content within the nine-piece limit, so the number of contents to be copied is reduced and it is treated as if it were rendered unplayable, but it is not necessary to render the original content outside the nine-piece limit unplayable.

When the stored content is copied to an external device as 2K or less content (content with a pixel count of 1920 x 1080 or less), the content protection process that protects the content as described above in accordance with the copy control information on the recording medium is hereafter referred to as "2K or less content protection process" when copying to an external device after storage.

(4-4) When pixel count conversion is performed on received over 2K content (content with a pixel count exceeding 1920 x 1080) to convert it to 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, pixel count conversion is not performed on the 2K or less content (content with a pixel count of 1920 x 1080 or less) when copying it to an external device after storage.

In this case, the content to be copied to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (4-3) above, so the "2K or less content protection process" described in (4-3) is performed when copying to the external device after storage.

(4-5) When receiving over 2K content (content with a pixel count exceeding 1920 x 1080) and converting it to 2K or less content (content with a pixel count of 1920 x 1080 or less) by converting the pixel count, and storing the 2K or less content (content with a pixel count of 1920 x 1080 or less), the pixel count is converted when copying the stored 2K or less content to an external device and then converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less)

In this case, the content to be copied to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (4-3) above, so the "2K or less content protection process" described in (4-3) is performed when copying to the external device after storage.

(4-6) When pixel count conversion is not performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is stored without pixel count conversion, or when pixel count conversion is performed on received 2K or less content (content with a pixel count of 1920 x 1080 or less) that is converted to other 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, and pixel count conversion is not performed when copying to an external device after storage.

In this case, the content to be copied to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (4-3) above, so the "2K or less content protection process" described in (4-3) is performed when copying to the external device after storage.

(4-7) When the received 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored without pixel count conversion, or when the received 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less) is converted to another 2K or less content (content with a pixel count of 1920 x 1080 or less) and stored, the pixel count is converted when copying to an external device after storage.

In this case, the content to be copied to the external device is 2K or less content (content with a pixel count of 1920 x 1080 or less), which is the same as in (4-3) above, so the "2K or less content protection process" described in (4-3) is performed when copying to the external device after storage.

As explained above in (4-1) to (4-7), when copying to an external device after storage, content protection processing is switched depending on the pixel count of the content when copying to an external device after storage. When copying to an external device in the form of copy-restricted over 2K content (content with a pixel count exceeding 1920 x 1080), the content is copied with a higher level of content protection than when copying to an external device in the form of copy-restricted under 2K content (content with a pixel count of 1920 x 1080 or less). This allows for more added value over 2K content (content with a pixel count exceeding 1920 x 1080) to be appropriately protected even on external devices.

When copying content stored as "limited number of copies allowed" to an external device within the nine limit numbers mentioned above, the remaining number of copies that can be made is reduced by one equally whether the "over 2K content protection process" when copying to an external device after storage described in (4-1) to (4-7) above is used, or the "2K or less content protection process" when copying to an external device after storage is used, and there is no need to make any difference in the management of the number of copies that can be made based on the difference in the content protection process used when copying.

In addition, in any of the external output processing, external move processing, and external copy processing described above, it is sufficient to configure the process so that output, move, or copy is prohibited for external devices that do not support the content protection function described in each condition.

In addition, if the "digital_recording_control_data" information or "encryption_mode" information that protects the same received content is transmitted via the broadcast transmission path in multiple different tables or descriptors, or is transmitted via both the broadcast transmission path and the communication line in the same or different tables or descriptors, a predetermined priority determination process based on the type of table or descriptor or the type of transmission path can be used to select the information with the highest priority for the content protection process described in this embodiment.

HDCP, which is the content protection method used in the above-mentioned external device output processing before accumulation and external device output processing after accumulation, is a content protection method that protects content such as decoded video, while DTCP, DTCP-IP, and DTCP2, which are used in processing such as moving and copying to an external device after accumulation, are content protection methods that protect content such as encoded video, and the types of content to be protected are different. Despite this, the threshold value when switching content protection processing according to the pixel count of the content in the broadcast receiver 100 of the third embodiment is set equal at the boundary between over 2K content (content with a pixel count exceeding 1920 x 1080) and 2K or less content (content with a pixel count of 1920 x 1080 or less). In this way, by making the switching threshold value when switching content protection processing according to the pixel count equal even for content protection methods with different types of protected content, it is possible to minimize the number of types of conditional branching for switching content protection processing, and it is possible to simplify the processing, which is effective.

According to the third embodiment of the present invention described above, the content protection process is switched according to the number of pixels of the content not only in the output process to an external device before the content is stored, but also in the output process to an external device after the content is stored, the move process to an external device, or the copy process to an external device. This allows high-pixel-count content with higher added value to be appropriately protected in external devices. Furthermore, during the storage of content, the process can be simplified by performing common content protection regardless of the number of pixels of the content. In other words, in the case of output process, move process, or copy process to external devices with various content protection levels, the content protection process is switched according to the number of pixels of the content, and the storage of content that can only be played on the device itself can be simplified by performing common content protection regardless of the number of pixels of the content.

Example 4
The following describes the fourth embodiment of the present invention. The fourth embodiment of the present invention has the same hardware configuration as the broadcast receiver 800 in the second embodiment, and the configuration, processing, effects, etc. of the fourth embodiment are the same as those of the second embodiment except for the content protection processing. Therefore, the following mainly describes the differences between the second embodiment and the present embodiment, and omits as much as possible the description of the common points to avoid duplication.

The fourth embodiment of the present invention has a hardware configuration similar to that of the broadcast receiver 800 in the second embodiment, and performs control to realize a different copyright protection function. Note that the content protection control for video content is described in this embodiment, and for audio, the same control as described below may be performed, or different content protection control may be performed.

Figure 29 is a table summarizing the processing of the copyright protection function in the broadcast receiving device 800 of Example 4. In the broadcast receiving device 800 of Example 4, the copyright protection processing for the content before and after the content storage processing is switched depending on whether the received content is 2K or more content (content having a pixel count exceeding 1920 x 1080), such as 4K content (pixel count 3840 x 2160) or 8K content (pixel count 7680 x 4320), or 2K or less content (content having a pixel count of 1920 x 1080 or less).

In Figure 29, the content protection process shown in the row where the transmission method is MMT is the content protection process applied to the content that undergoes reception processing by the MMT decoding processing unit 841 of the broadcast receiver 800 in Figure 24, and since the content is the same as the content protection process in Figure 28 described in Example 3, its description will be omitted.

On the other hand, in FIG. 29, the content protection process shown in the row where the transmission method is MPEG2-TS is the content protection process applied to the content that undergoes reception processing by the MPEG2-TS decode processing unit 842 of the broadcast receiver 800 in FIG. 24.

All content received by the broadcast receiver 800 of the fourth embodiment of the present invention using the MPEG2-TS transmission method is assumed to be 2K or less content (content with a pixel count of 1920 x 1080 or less).

Since all content received via the MPEG2-TS transmission method is 2K or less content (content with a pixel count of 1920 x 1080 or less), the broadcast receiver 800 of the fourth embodiment of the present invention standardizes processing for 2K or less content received via the MPEG2-TS transmission method (content with a pixel count of 1920 x 1080 or less) and 2K or less content received via the MMT transmission method (content with a pixel count of 1920 x 1080 or less). Specifically, in either case, content protection processing can be performed on 2K or less content received via the MMT transmission method (content with a pixel count of 1920 x 1080 or less) as described in the third embodiment.

The MMT transmission method and the MPEG2-TS transmission method have different formats for the tables in which the control information used for content protection is transmitted. Specifically, in the MMT transmission method, the content copy control descriptor and the content usage control descriptor are transmitted, for example, mainly in the MPT (also in the MH-EIT and MH-SDT). In contrast, in the MPEG2-TS transmission method, the corresponding copy control related information, the digital copy control descriptor and the content usage descriptor, are transmitted, for example, mainly in the PMT (Program Map Table) (also in the EIT and SDT). Therefore, the formats of the tables and descriptors in which the copy control related information is transmitted are different.

However, the "digital_recording_control_data" parameter and the "copy_restriction_mode" parameter stored in the descriptor can use the same format for both the MMT transmission method and the MPEG2-TS transmission method. Therefore, in the broadcast receiver 800 of the fourth embodiment of the present invention, the interpretation of the "digital_recording_control_data" parameter and the "copy_restriction_mode" parameter that specify content protection is standardized for both the MMT transmission method and the MPEG2-TS transmission method.

This allows the external output process before content storage, content storage process, external output process after content storage, move process to an external device after content storage, and copy process to an external device after content storage to be standardized between 2K or less content (content with a pixel count of 1920 x 1080 or less) received via the MPEG2-TS transmission method and 2K or less content (content with a pixel count of 1920 x 1080 or less) received via the MMT transmission method, simplifying the process. The specific processes for each are content protection processes for 2K or less content (content with a pixel count of 1920 x 1080 or less) received via the MMT transmission method described in Example 3. The details have already been described in Example 3, so a description thereof will be omitted.

Furthermore, by standardizing this process, the content protection process for 2K or less content (content with a pixel count of 1920 x 1080 or less) received via the MPEG2-TS transmission method can be standardized not only for 2K or less content (content with a pixel count of 1920 x 1080 or less) received via the MMT transmission method, but also for over 2K content (content with a pixel count of more than 1920 x 1080) received via the MMT transmission method, by using a pixel count conversion process before or after the content is stored, resulting in a very significant simplification of the process.

According to the fourth embodiment of the present invention described above, it is possible to obtain the same effect as in the third embodiment for content received via the MMT transmission method. Furthermore, for content with a predetermined number of pixels or less, the content protection process can be made common for both the content received via the MMT transmission method and the content received via MPEG2-TS not only in the output process to an external device before the content is stored, but also in the output process to an external device after the content is stored, the move process to an external device, or the copy process to an external device, making it possible to simplify the process regardless of the transmission method.

Although examples of the embodiment of the present invention have been described above using Examples 1 to 4, the configurations for realizing the technology of the present invention are not limited to the above examples, and various modifications are possible. For example, it is possible to replace part of the configuration of one example with the configuration of another example, and it is also possible to add the configuration of another example to the configuration of one example. All of these fall within the scope of the present invention. Furthermore, the numerical values and messages that appear in the text and figures are merely examples, and the effect of the present invention will not be impaired even if different ones are used.

The functions of the present invention described above may be realized in part or in whole by hardware, for example by designing them as integrated circuits. They may also be realized by software, with a microprocessor unit or the like interpreting and executing an operating program that realizes each function. Hardware and software may also be used in combination.

The software that controls the broadcast receiving device 100 may be stored in the ROM 103 and/or storage (accumulation) unit 110 of the broadcast receiving device 100 beforehand at the time of product shipment. It may also be acquired via the LAN communication unit 121 from another application server 500 on the Internet 200 after product shipment. In addition, the software stored on a memory card, optical disk, etc. may be acquired via the expansion interface unit 124, etc.

The control and information lines shown in the diagram are those considered necessary for explanation, and do not necessarily represent all control and information lines on the product. In reality, it is safe to assume that almost all components are interconnected.

100, 800...Broadcast receiving device, 100a...Antenna, 101, 801...Main control unit, 102, 802...System bus, 103, 803...ROM, 104, 804...RAM, 110, 810...Storage unit, 121, 821...LAN communication unit, 124, 824...Expansion interface unit, 125, 825...Digital interface unit, 131, 831, 832...Tuner/demodulation unit, 132...Separation unit, 141...Video decoder, 142...Video color gamut conversion unit, 143...Audio decoder, 144...Text superimposition decoder, 145...Subtitle decoder, 146...Subtitle synthesis unit, 147...Subtitle color gamut conversion unit, 151...Data decoder, 152...Cache unit, 153...Application control unit, 154...Browser unit , 155...application color gamut conversion unit, 156...sound source unit, 161, 861...video synthesis unit, 162, 862...monitor unit, 163, 863...video output unit, 164, 864...audio synthesis unit, 165, 865...speaker unit, 166, 866...audio output unit, 170, 870...operation input unit, 841...MMT decode processing unit, 842...MPEG2-TS decode processing unit, 200...Internet, 200r...router device, 200a...access point, 300t...radio tower, 300s...broadcast satellite (or communication satellite), 300...broadcast station server, 400...service provider server, 500...other application servers, 600...mobile telephone communication server, 600b...base station, 700...mobile information terminal.

Claims (1)

A content protection processing method in a transmission system in which a broadcast program content is transmitted from a broadcast station and the broadcast program content is received by a broadcast receiving device, comprising the steps of:
a transmission step of transmitting the broadcast program content from the broadcast station to the broadcast receiving device in the transmission system;
a receiving step in which the broadcast program content transmitted by the transmission system is received by the broadcast receiving device;
a storage step in which the broadcast receiving device stores the broadcast program content received in the receiving step;
a copy processing step in which the broadcast receiving device copies the broadcast program content stored in the storage step;
a move processing step in which the broadcast receiving device moves the broadcast program content stored in the storage step;
Equipped with
In the storing step, when the broadcast program content received in the receiving step is a content transmitted in the transmission system with protection designated to allow a predetermined number of copies, the broadcast program content is stored in a state in which nine copies and one move process are possible for the broadcast program content;
In the copy processing step, when the broadcast program content stored in the storage step is copied to an external device, content protection is performed by DTCP2, and copying can be performed using a move processing function of DTCP2;
The storage in the storage step can be performed in a storage unit at an output destination of an IP interface configured by hardware corresponding to Ethernet provided in the broadcast receiving device,
In the storing step, the broadcast program content can be stored in an encrypted state so that the broadcast program content can be played back only by the broadcast receiving device.
Content protection processing method.

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