JP2019208213A - Content transmitting device and content transmitting method for the same - Google Patents

Abstract

To securely transmit contents according to a function on a content receiving side, in an environment where a plurality of digital instruments displaying contents with different qualities are mixed.SOLUTION: A method for transmitting a content from a transmitting device to a receiving device has first encryption processing means that encrypts a content through first encryption processing, second encryption processing means that encrypts a content through second encryption processing different from the first encryption processing, and conversion means that converts the content. The content has associated downconversion restriction information. When the downconversion restriction information permits downconversion, and the content receiving device does not support the second encryption processing, the content transmitting device converts the content to be adapted to the first encryption processing, encrypts the converted content through the first encryption processing, and transmits the content.SELECTED DRAWING: Figure 12

Description

The present invention relates to a content transmission device and a content transmission method thereof, and more particularly, to a content transmission device suitable for securely transmitting content according to a function of a content reception side, and a content transmission method thereof.

In recent years, with the advancement of electronic technology and communication technology, it has become possible to easily enjoy digital content on a home network built in the home. Digital content has the advantage that it can provide high-definition and beautiful images to users, and can provide various accompanying information services. On the other hand, unlike copying of analog data, digital content does not deteriorate in image quality when copied by digital processing. Therefore, how to protect the copyright in order to prevent illegal copying becomes a problem.

Thus, from the viewpoint of copyright protection, DTCP (Digital Transmission Content Protection) is a standard established for preventing illegal copying. DTCP is a copyright protection method used for the purpose of audio / video copy prevention in a home network / personal network, and is an interconnection guideline for sharing image / audio data mainly between digital devices. Used with DLNA (Digital Living Network Alliance). DTCP uses a common key encryption method that performs encryption by exchanging a common key between digital devices. For example, Patent Document 1 discloses a technique for transmitting and receiving digital data between digital devices using a common key.

On the other hand, with the advancement of smartphone functionality, smartphones and home appliances that control home appliances and distribute digital content are attracting attention. Regarding the technology related to this content transmission, Patent Document 2 discloses that a user selects an external output device (TV or the like) with a smartphone (mobile phone terminal), and the processing capability of the selected external output device and its output device. The identification information for identifying is specified. Then, it requests the home server to transmit content suitable for the processing capability of the external output device to the external output device, and the external output device receives the content transmitted from the home server accordingly and outputs the image. Techniques to do this are disclosed.

JP 2007-174249 A JP 2012-43464 A

With the advancement of digital technology, a standard (4K / 8K) with higher resolution (number of pixels) of video and moving images than the current HD TV broadcasting has been formulated, and 4K broadcasting has partially started. In the current Full HD (2K) standard, the number of pixels is 1920 × 1080 (1080i, 1080p), but in the 4K UHD standard, the number of pixels is 3840 × 2160 (2160p), and in the 8K UHD standard, the number of pixels is The number is 7680 × 4320 (4320p). In addition, UHD BD (Ultra HD Blu-ray) (registered trademark) is a next-generation standard related to optical disks, and 3840 × 2160 (2160p) is defined as the number of pixels.

With such high-quality video content, it is important to construct a mechanism for displaying and viewing on an arbitrary monitor device while protecting the copyright. In addition, due to the low price and widespread use of PCs (Personal Computers), tablets, and smartphones, there have been a number of digital devices equipped with monitors in ordinary households. Content based on the conventional Full HD (2K) standard ( (Hereinafter referred to as “2K content”) and content based on the new 4K / 8K standard, how to display on a plurality of digital devices becomes a problem.

There is a demand for a content provider to restrict viewing / copying by distinguishing high-quality 4K / 8K content from conventional content for the purpose of a premium service or the like. On the other hand, a device (content transmitting device) that has received 4K / 8K content subject to copyright protection via broadcasting or the Internet safely transmits these content to other devices (content receiving device) according to the intention of the content provider. There is a need to.

Furthermore, when there are a plurality of devices that display received content in the home or office, there is a request that the content transmission device wants to easily view 4K / 8K content on a desired device.

In Patent Document 1 of the above-mentioned prior art, a transmission method encrypted by DTCP of content to be protected by copyright is described, but a transmission technology for distinguishing and handling a plurality of contents having different qualities such as 4K / 8K contents. Is not considered. In Patent Document 2, it is possible to select an external output device according to the processing capability of the output destination, but the encryption processing is not considered.

The present invention has been made to solve the above-described problems, and its purpose is to secure content according to the function of the content receiving side in an environment in which digital devices displaying a plurality of different quality contents are mixed. It is possible to provide a content transmission device such as a smartphone that enables a high-quality content of a new standard to be displayed on a reception device that can display only content of conventional quality.

In order to achieve the above object, a preferred configuration of the content transmission apparatus of the present invention is a content transmission apparatus that transmits digital content to a content reception apparatus, and the digital content is encrypted by digital communication I / F (Inter Face). Transmitting means, first encryption processing means for encrypting low resolution content by first encryption processing, and second encryption processing means for encrypting high resolution content by second encryption processing And down-converting means for down-converting the high-resolution content into the low-resolution content. And, from the digital receiving device, information related to the encryption processing of the digital receiving device is received, and when the digital receiving device supports the second encryption processing, it is encrypted by the second encryption processing means, When high-resolution content is transmitted and the digital receiver does not support the second encryption process, the high-resolution content is down-converted, and the down-converted content is encrypted by the first encryption process and transmitted. To do.

According to the present invention, in an environment in which digital devices that display a plurality of contents are mixed, it is possible to transmit contents securely according to the function of the contents receiving side, and only the contents of the conventional standard can be displayed. It is possible to provide a content transmission device such as a smartphone that enables the reception device to display high-quality content of the new standard.

It is a schematic diagram of a home network and its related components. It is a block diagram of a smart phone (content transmission device). It is a block diagram of the television receiver (content transmission / reception apparatus) with a built-in recorder. It is a block diagram of a television receiver (content receiving device). It is a data flow figure in a content transmitter. It is a function in a content receiver, and a data flow figure. It is a figure which shows an example of the content transmission packet of encryption process I support. It is a figure which shows an example of the header part of the content transmission packet of encryption process II support. It is a figure which shows an example of the extended copy control information in encryption process II support. It is a figure which shows an example of the data in the case of transmitting a content using an HTTP protocol according to the format shown to FIG. 7B. It is a figure which shows an example of an apparatus information definition table. It is a figure which shows an example of an apparatus control information table. It is a figure which shows an example of an apparatus information table. It is a figure which shows an example of a content utilization descriptor. It is a figure which shows an example of a digital copy control descriptor. It is a figure which shows an example of a down conversion restriction | limiting descriptor. It is a figure which shows an example of a digital content output control table. It is a figure which shows an example of a digital content recording control table. It is a general flowchart when transmitting a content from a content transmitter to a content receiver. It is a sequence diagram of an apparatus information acquisition process. It is a sequence diagram of a device authentication process. It is a figure which shows an example of the user interface which displays apparatus information. It is a figure which shows an example of the user interface of a content viewing / transmission application.

Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.

First, the configuration of a home network and components related thereto according to an embodiment will be described with reference to FIGS.
FIG. 1 is a schematic diagram of a home network and its related components.
FIG. 2 is a configuration diagram of a smartphone (content transmission device).
FIG. 3 is a block diagram of a recorder built-in television receiver (content transmitting / receiving apparatus).
FIG. 4 is a configuration diagram of a television receiver (content receiving device).
FIG. 5 is a data flow diagram in the content transmission apparatus.

In the present embodiment, the content transmission apparatus receives 4K / 8K content, down-converts it with the same resolution or according to the function of the content reception apparatus, and transmits the content to the content transmission apparatus. explain.

As shown in FIG. 1, the home network of the present embodiment includes a smartphone 100 and a tablet 50 as portable devices in one home, a recorder built-in television receiver 200, a television receiver 300, and a notebook computer. Assume that 400 is placed.

The smartphone 100 and the tablet 50 function as a content transmission device, the television receiver 300 and the notebook computer 400 function as a content reception device, and the recorder built-in television receiver 200 has both of these functions. It shall function as a content transmission / reception function.

As a network configuration, the wireless access point 20, the router 12, the hub 11, the recorder built-in television receiver 200, and the television receiver 300 are connected by wire, and the smartphone 100, the tablet 50, and the notebook computer 400 are IEEE 802.11. Communication is performed by wireless LAN (WiFi) according to wireless LAN standards such as a / b / g / n / ac standards.

Regarding the provision of content, the antenna 42 receives broadcast radio waves transmitted from the broadcast station 5 and distributes them to the television receiver 200 with a built-in recorder and the television receiver 300. The smartphone 100 and the tablet 50 can also receive broadcast radio waves transmitted by the broadcast station 5. In addition, the content providing server 6 distributes the content to the recorder built-in television receiver 200 and the television 300 via the Internet 60 through the route of the router 12 and the hub 11. The content providing server 6 can also distribute content from the base station 7 to the smartphone 100 and the tablet 50 via a wireless line (Long Term Evolution) such as an LTE line.

The smartphone 100 and the tablet 50 can receive 4K / 8K content and 2K content distributed by the broadcasting station 5 and distribute them to the television receiver 200 with a recorder and the television receiver 300.

On the other hand, the television receiver 200 with a built-in recorder can receive and display 4K / 8K content, and the television receiver 300 can receive and display only 2K content.

In a network, standard IP (Internet Protocol) is used as a network protocol, and TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are used as upper transport protocols. For transmission of content, higher-level application protocols such as RTP (Real-time Transport Protocol), HTTP (Hyper Text Transfer Protocol), FTP (File Transfer Protocol), and the like are used.

The smartphone 100, the tablet 50, the recorder built-in television receiver 200, the television receiver 300, the notebook computer 400, and the router 12 each have an IP address for identifying themselves on the IP network. Further, a 48-bit MAC (Media Access Control) address is given to the interface unit of each network communication processing circuit. For setting the IP address to each device, for example, the router 12 may be operated as a DHCP server by DHCP (Dynamic Host Configuration Protocol), and the IP address of each device may be allocated from here.

As shown in FIG. 2, the smartphone 100 includes, as hardware, a CPU (Central Processor Unit) 102, a main memory 104, a wireless LAN unit 106, an RF unit 108, a baseband processor 110, a tuner 112, a demultiplexer 114, and a decoder. 116, HDMI output unit 118, display I / F (Inter Face) 120, audio I / F 130, camera 140, GPS 142, short-range sensor 144, acceleration sensor 146, short-range wireless unit 148, and flash memory 150 are connected by a bus. Has been configured. In addition, a display 122 and a touch panel 124 are connected to the display I / F 105, and a speaker 132 and a microphone 134 are connected to the audio I / F 109.

The CPU 100 is a unit for calculation / control that controls each unit of the smartphone 100 and executes a program for content transmission loaded on the main memory 104. The CPU 100 performs various processes by reading the program stored in the flash memory 150 into the main memory 104 and executing it. These programs and data may be stored in the flash memory 150 in advance, may be input from a storage medium such as a USB memory, or may be downloaded from an external server or the like via a network. Further, the function realized by the program may be realized by dedicated hardware.

The main memory 104 is a storage device that loads and temporarily stores a program stored in the flash memory 150 or stores work data.

The wireless LAN unit 106 is a part that communicates with neighboring wireless access points 20 according to wireless LAN standards (for example, IEEE 802.11 a / b / g / n / ac).

The RF unit 108 is an interface device for converting a signal of the baseband processor 110 into a high-frequency signal in the radio band, and conversely, converting a radio frequency signal in the radio band into a signal of the baseband processor 110. The smartphone 100 can communicate with the content providing server 6 via the RF unit 108 via the base station 7 via a 3G line or a 4G line, or can download content via the Internet 60.

The baseband processor 110 is a processor that controls modules related to communication and telephone calls of the smartphone 100.

The tuner 112 receives content of a digital broadcasting service (such as terrestrial broadcasting or satellite broadcasting) distributed by the broadcasting station 5 (content provider) via the internal antenna of the smartphone 100, and selects a desired channel from a plurality of channels. And demodulate digitally modulated programs. In addition, as necessary, the program scramble is canceled so that only a channel contracted with the content provider can be received using an encryption / decryption program described later. The tuner 112 of the smartphone 100 according to the present embodiment includes both a 4K / 8K tuner 112a and a 2K tuner 112b that can handle broadcasting for 4K / 8K content and broadcasting for conventional content such as SD / HD / Full HD.

The demultiplexer 114 is a part that extracts audio data, video data, program information, data, copy control information, and the like from a broadcast program.

The decoder 116 is a part that decodes compressed audio data and video data included in a broadcast program input via the tuner 112 and content stored in the flash memory 150 and expands the original audio signal and video signal. is there. The decoder 116 of the smartphone 100 according to the present embodiment includes both a 4K / 8K decoder 116a and a 2K decoder 116b that can handle broadcasting for 4K / 8K content and broadcasting for conventional content.

An HDMI (registered trademark) (High-Definition Multimedia Interface) output unit 118 is a part that converts digital data into an HDMI signal and outputs it. Although wired is shown in FIG. 2, it may be wireless.

The display I / F 120 is an interface for connecting the display 122 and the touch panel 124. The display 122 is a display device that displays image information to a user, such as a liquid crystal display or an organic EL (Electro-Luminescence) display, and a display having a screen size of about 3 inches to 5 inches is generally used. . The touch panel 124 is an input device having a mechanism for inputting data and commands when the user touches the display 122 with a finger or a touch pen.

The audio I / F 130 is an interface for connecting a microphone 134 and a speaker 132. The microphone 134 is a device that collects sound from the outside. The speaker 132 is a device that outputs sound.

The camera 140 captures the situation around the smartphone 100 and stores it in the flash memory 150 as image data.

A GPS (Global Positioning System) unit 142 is a device that receives radio waves from an artificial satellite and analyzes the radio waves to determine the position of the device.

The distance image sensor 144 is a sensor that captures an image of a surrounding object and obtains a distance to the object.

The acceleration sensor 146 is a sensor that measures acceleration generated in the smartphone 100. The measured acceleration is used, for example, for screen display switching.

The short-range wireless unit 148 is a device for operating a digital device such as a nearby speaker according to a communication standard such as Bluetooth (registered trademark).

The flash memory 150 is a non-volatile memory that normally has a larger capacity than the main memory 104 and stores programs and data. The flash memory 150 is a relatively large-capacity storage device that stores various data such as sound source data, moving image data, and image data, and programs such as application software for programs for content transmission.

The flash memory 150 stores a monitor identification program 152, a down-conversion program 154, an encryption / decryption program 156, a device authentication program 158, a device management program 160, and a recording / playback program 162 as programs executed by the CPU 102.

The monitor identification program 152 uses the visible image captured by the camera 140, the distance image captured by the distance image sensor 144, and information transmitted / received via the wireless LAN unit 106 or the short-range wireless unit 148. This program obtains the manufacturer name, model, and device type.

The down-conversion program 154 is a program that generates content data in which the content resolution is reduced from the original image.

The encryption / decryption program 156
(1) A predetermined procedure (for example, ARIB) in which the content provider specifies / operates the broadcast program provided by the broadcasting station 5 received via the tuner 112 and the content provided by the content providing server 6 received via the content wireless LAN unit 106 , Marlin, PlayReady, CMLA-OMA V2, etc.)
(2) In order to record the content decrypted in (1) on the recording medium, it is encrypted according to a predetermined procedure prescribed / operated by the content provider, and further decrypted in order to use the recorded content,
(3) A content provider for decompressing the content decoded in (1) or (2) by the decoder 116 and then transmitting it to the external television receiver (content receiving device) via the HDMI output unit 118 Decrypt according to the prescribed procedure prescribed / operated by
(4) In order to transmit the content decrypted in (1) or (2) to another content receiving device via the wireless LAN unit 106, the content is decrypted according to a predetermined procedure prescribed / operated by the content provider.
It is a program to do.

Whether the device authentication program 158 is a device that has been authorized by a specific authentication protocol with another digital device in order to transmit content subject to copyright protection via a wired or wireless network. Is a program for sharing a key used for content encryption / decryption.

The device information management program 160 is a program for managing information related to network connection devices successfully authenticated by the device authentication program 158 and information necessary for the device authentication processing unit 108 to perform device authentication.

The recording / reproducing program 162 performs recording control for recording content on a recording medium such as the flash memory 150 and a memory card (not shown), and reproduction control for reproducing the content recorded on the recording medium.

As shown in FIG. 3, the recorder built-in television receiver 200 includes, as hardware, a CPU (Central Processor Unit) 202, a main memory 204, an HDMI input / output unit 206, a wired LAN unit 208, a tuner 210, and a demultiplexer 212. The decoder 214, the display I / F 216, the audio I / F 218, and the auxiliary storage I / F 220 are connected by a bus. A display 250 is connected to the display I / F 216, and a speaker 260 and an input unit 270 are connected to the audio I / F 218.

The CPU 202 is a unit for calculation / control that controls each unit of the television receiver 200 with a built-in recorder and executes a program for content transmission and reception loaded on the main memory 204. The CPU 202 performs various processes by reading the program stored in the flash memory 230 into the main memory 204 and executing it. These programs and data may be stored in the flash memory 230 in advance, may be input from a storage medium such as a USB memory, or may be downloaded from an external server or the like via a network. Further, the function realized by the program may be realized by dedicated hardware.

The main memory 204 is a storage device that loads and temporarily stores a program stored in the flash memory 230 and stores work data.

An HDMI (registered trademark) (High-Definition Multimedia Interface) input / output unit 206 is a part that inputs an HDMI signal and converts it into digital data, or converts the digital data into an HDMI signal and outputs it.

The wired LAN unit 208 is a part that performs interface processing for communication according to the standard (for example, Ethernet (registered trademark)) of the wired network connected to the port.

The tuner 210 receives the content of a digital broadcast service (terrestrial broadcast, satellite broadcast, etc.) distributed by the broadcast station 5 (content provider) via the internal antenna of the recorder built-in television receiver 200, and from a plurality of channels. Select the desired channel and demodulate the digitally modulated program. The tuner 210 of the television receiver 200 with a built-in recorder of the present embodiment has both a 4K / 8K tuner 210a and a 2K tuner 210b that can handle broadcasting for 4K / 8K content and broadcasting for 2K content.

The demultiplexer 212 is a part that extracts audio data, video data, program information, data, copy control information, and the like from a broadcast program.

The decoder 214 decodes the compressed audio data and video data included in the broadcast program input via the tuner 210 and the content recorded in the HDD 222 and the optical disk device 224, and expands the original audio signal and video signal. Part. The decoder 214 of the television receiver 200 with a built-in recorder according to the present embodiment has both a 4K / 8K decoder 214a and a 2K decoder 214b that can handle broadcasting for 4K / 8K content and broadcasting for 2K content.

The display I / F 216 is an interface for connecting the display 250. The display 250 is a display device that displays image information to a user, such as a liquid crystal display or an organic EL (Electro-Luminescence) display, and a display having a screen size of about 20 inches to 40 inches is generally used. .

The audio I / F 218 is an interface for connecting a speaker 232 and headphones (not shown).

The auxiliary storage I / F 220 is an interface for connecting an auxiliary storage device having a larger capacity than the main memory 204 and the flash memory 230 such as an HDD (Hard Disk Drive) 222 and an optical disk device 224. The optical disc device is a device that reads from and writes to an optical disc medium such as a Blu-ray Disc (registered trademark) or a DVD (Digital Versatile Disc) (registered trademark).

The flash memory 230 is generally a non-volatile memory that has a larger capacity than the main memory 204 and stores programs and data. The flash memory 230 is a storage device that stores various types of data such as sound source data and moving image data, and programs such as application software for programs for transmitting and receiving content.

The flash memory 230 stores a monitor identification program 232, a down-conversion program 234, an encryption / decryption program 236, a device authentication program 238, a device management program 240, and a recording / playback program 242 as programs executed by the CPU 202.

The monitor identification program 232 is a program for determining the type of content receiving device (the type of encryption processing described later) when transmitting content from the recorder built-in television receiver 200 (content transmitting / receiving device) 200.

The down-conversion program 234 is a program that generates content data in which the content resolution is reduced from the original image.

The encryption / decryption program 236
(1) A predetermined procedure (for example, ARIB, DTCP-) for specifying / operating the content provider from the broadcast program provided by the broadcasting station 5 received via the tuner 210 and the content provided by the content providing server received via the wired LAN unit 208 IP, Marlin, PlayReady, CMLA-OMA V2, etc.)
(2) Predetermined procedure for defining / operating content provider (for example, ARIB, DTCP-IP, Marlin, PlayReady, CMLA-OMAV2, etc.) for content re-transmitted from other content transmission devices via the wired LAN unit 208 According to
(3) In order to record the content decrypted in (1) or (2) on the recording medium of the HDD 222 or the optical disc apparatus 224, the content is encrypted according to a predetermined procedure prescribed / operated by the content provider, and the recorded content is further recorded. Decrypt, to use
(4) The content decoded in (1), (2), or (3) is decompressed by the decoder 214 and then transmitted to the external television receiver (content receiving device) via the HDMI input / output unit 206. In accordance with a predetermined procedure prescribed / operated by the content provider,
(5) In order to transmit the content decrypted in (1) or (3) to another content receiving device via the wired LAN unit 208, the content is decrypted according to a predetermined procedure prescribed / operated by the content provider. It is a program.

Whether the device authentication program 238 is a device that is authorized by a specific authentication protocol with another digital device in order to transmit copyrighted content over a wired or wireless network. Is a program for sharing a key used for content encryption / decryption.

The device information management program 240 is a program for managing information related to network-connected devices successfully authenticated by the device authentication program 238 and information necessary for the device authentication program 238 to perform device authentication.

The recording / reproducing program 242 performs recording control for recording the content on the recording medium of the HDD 222 or the optical disc apparatus 224 and reproduction control for reproducing the content recorded on the recording medium. The content subject to copyright protection is encrypted, recorded, decrypted and reproduced according to a predetermined procedure using the encryption / decryption program 240.

The input unit 270 is an input device for the user to operate the recorder built-in television receiver 200, and examples include a remote controller, a mouse, and a keyboard.

As shown in FIG. 4, the television receiver (content receiver) 300 includes, as hardware, a CPU 302, a main memory 304, an HDMI input unit 306, a wired LAN unit 308, a tuner 308, a demultiplexer 310, a decoder 312, A display I / F 314 and an audio I / F 316 are connected by a bus. A display 350 is connected to the display I / F 314, and a speaker 360 and an input unit 370 are connected to the audio I / F 316.

The configuration of the television receiver 300 is almost the same as the configuration of the television receiver 300 with a built-in recorder shown in FIG. 3, except that it does not have a recorder function such as an auxiliary storage I / F, HDD, or optical disk device. ing.

The program stored in the flash memory 330 stores only an encryption / decryption program 336, a device authentication program 338, and a recording / playback program 342 used for content transmission, and includes a monitor identification program, a down-conversion program, The difference is that it does not have a device management program.

The tuner 308 is used when receiving and demodulating a broadcast wave, but is not used when receiving content from a content transmitter via a network. Furthermore, since the video content that can be processed by the television receiver of this embodiment is 2K or less, the tuner 308 has only the 2K tuner 308b, and the decoder 312 has only the 2K decoder 312b.

Next, functions and data flows in the content transmission apparatus will be described with reference to FIG.

First, encryption processing described in this embodiment will be described.

Currently, HDCP (High-bandwidth Digital Content Protection) is employed as digital signal encryption processing for HDMI. In the present embodiment, the HDCP standard for encryption processing for 2K or less content is described as HDCP1, and the HDCP standard for encryption processing for 4K / 8K content, which is an extended standard, is described as HDCP2. Further, as encryption processing used for copy protection on a home network / personal network of a wired LAN or wireless LAN, encryption processing for 2K or less content is described as encryption processing I, and encryption processing II for 4K / 8K content is described.
The content transmission device (smart phone 100, recorder built-in television receiver 200) shown in FIG. 5 receives both 4K / 8K content and 2K or less content (hereinafter referred to as 2K content) received from the broadcasting station 5 as other content. It has a function to output to the receiving device.

First, a method for outputting received content in an uncompressed digital format to an external monitor in the HDMI format will be described.

When 4K / 8K content is received, a desired channel is demodulated from a plurality of channels by the 4K / 8K tuner unit 401a, descrambled as necessary, and input to the demultiplexer unit 402a. The demultiplexer unit 402a separates audio data and video data from the broadcast signal and inputs them to the 4K / 8K decoder unit 403a.

The 4K / 8K decoder unit 403a decodes the compressed audio data and video data into an uncompressed state and outputs the decoded data to the HDMI processing unit 405a. The HDMI processing unit 405a performs predetermined encryption according to the HDCP2 procedure, converts the signal into an HDMI standard signal, and outputs the signal from the HDMI terminal 410. This data flow is effective when the content receiving apparatus is a monitor capable of displaying 4K / 8K content.

Similarly, when 2K content is received, it is demodulated to a desired channel by the 2K tuner unit 401b, descrambled as necessary, and then input to the demultiplexer unit 402b. The demultiplexer unit 402b separates audio data and video data from the broadcast signal and inputs them to the 2K decoder unit 403b.

The 2K decoder unit 403b decodes the compressed audio data and video data into an uncompressed state, and outputs the decoded data to the HDMI processing unit 405b. The HDMI processing unit 405b performs predetermined encryption according to the HDCP1 procedure, converts the signal into an HDMI standard signal, and outputs the signal from the HDMI terminal 410. This data flow is effective when the content receiving apparatus is a monitor capable of displaying content of 2K or less.

In addition, a data flow in which the received 4K / 8K content is HDMI output to a monitor (content receiving device) capable of displaying 2K or less content will be described.
The signal output from the 4K / 8K decoder unit 403a is down-converted by the down-conversion unit 404 and converted into 2K content only when the content provider permits the change of the resolution, screen size, luminance range, etc. of the 4K / 8K content. The HDMI processing unit 405b encrypts the data using HDCP1 as encryption processing, converts the signal into an HDMI standard signal, and outputs the signal from the HDMI terminal 410.

Here, one or more HDMI terminals 410 may be provided, and each terminal may be shared by the HDMI processing unit 405a and the HDMI processing unit 405b, or a predetermined terminal may be explicitly assigned to each.

Next, a method for outputting the received content in a compressed digital format to another content receiving apparatus via the network will be described.

When 4K / 8K content is received, the authentication unit 406 is used to execute an authentication process, which will be described later, and only when it is confirmed that the destination content receiving device is a legitimate device, the demultiplexer unit 402a An output signal is input to the communication processing unit 407a.

The communication processing unit 407a uses the key information shared by the authentication unit 406 to perform encryption processing by encryption processing II and transmits a signal as a radio wave from the wireless LAN unit 412 to the content reception device, or by wired communication. The LAN terminal 414 transmits a signal by wire.

Similarly, when a content of 2K or less is received, the authentication unit 406 is used to execute an authentication process, which will be described later, and the demultiplexer unit only when it is confirmed that the destination content receiving device is a legitimate device The signal from 402b is input to the communication processing unit 407b. The communication processing unit 407b encrypts the content processing apparatus using the key information shared by the authentication unit 406 by encryption processing I as a cryptographic process, and transmits a signal as a radio wave from the wireless LAN unit 412 to the content receiving device, The LAN terminal 414 transmits a signal by wire. Here, the authentication unit 406 performs the authentication using different authentication algorithms or different parameters for the 4K / 8K content and the 2K content. The communication processing unit 407a and the communication processing unit 407b use key information having different values and data lengths.

In addition, regarding a data flow that is output to a network to a content receiver that cannot reproduce or record received 4K / 8K content as it is or a content receiver that wants to reduce the amount of data transferred or recorded on the network. explain. The signal from the demultiplexer unit 402a is input to the 4K / 8K decoder unit 403a only when the content provider permits the change of the resolution, screen size, luminance range, etc. of the 4K / 8K content, and the input data is not processed. After decoding into compressed data, the down-conversion unit 404 down-converts the signal. Thereafter, the data is compressed by the encoding unit 408, and the compressed data is output to the communication processing unit 407b. The communication processing unit 407b encrypts the content processing apparatus using the key information shared by the authentication unit 406 by encryption processing I as a cryptographic process, and transmits a signal as a radio wave from the wireless LAN unit 412 to the content receiving device, The LAN terminal 414 transmits a signal by wire.

Next, functions and data flow in the content receiving apparatus will be described with reference to FIG.
FIG. 6 is a function and data flow diagram in the content receiving apparatus.
The content receiving apparatus shown in FIG. 6 has a function of receiving both 4K / 8K content and 2K or less content and displaying them on a built-in or external monitor.

The HDMI signal input from the HDMI terminal 430 is decoded by the HDMI processing unit 425a in the case of 4K / 8K content, and is output to the display unit 428 for display. In the case of 2K content, it is decoded by the HDMI processing unit 425b, output to the display unit 428, and displayed.

On the other hand, when the signal received by the wireless LAN unit 412 or the wired LAN terminal 414 is 4K / 8K content, the communication processing unit 427a uses the key shared in the authentication processing with the content transmission apparatus by the authentication unit 426 to perform encryption processing. The data is decoded by II and output to the 4K / 8K decoder unit 423a. The 4K / 8K decoder unit 423a decodes the input signal, and outputs the decoded signal to the display unit 428 for display. Similarly, in the case of 2K content, the communication unit 427b uses the key shared in the authentication process with the content transmission apparatus by the authentication unit 426 to be decrypted by the encryption process I and output to the 2K decoder unit 423b. The 2K decoder unit 423b decodes the input signal and outputs it to the display unit 428 for display.

Although not shown in the figure, the content receiving apparatus may include a recording / reproducing unit for an HDD or an optical disc, and a communication processing unit that receives the encrypted compressed digital content received by the wireless LAN unit 412 or the wired LAN unit 414. After decrypting at 472a or 427b, it is encrypted again according to a predetermined procedure permitted by the content provider and recorded on a recording medium such as an HDD or an optical disk.

Next, a data structure related to content transmission / reception will be described with reference to FIGS. 7A to 7D.
FIG. 7A is a diagram illustrating an example of a content transmission packet for cryptographic processing I support.
FIG. 7B is a diagram illustrating an example of a header portion of a content transmission packet supporting encryption processing II.
FIG. 7C is a diagram showing an example of extended copy control information in the encryption processing II support.
FIG. 7D is a diagram illustrating an example of data when content is transmitted using the HTTP protocol in accordance with the format illustrated in FIG. 7B.

As shown in FIG. 7A (a), the content transmission packet related to the encryption process I is a data packet exchanged between the content transmission device and the content reception device, and includes a header portion 801 and a payload portion 802.

As shown in FIG. 7A (b), the header portion 801 includes a reserved area (Reserved) 8011, an encryption method (C_A) 8012, an encryption mode (E-EMI) 8013, an exchange key label (Exchange_Key_Label) 8014, a random value ( Nc) 8015, and payload size (Byte Length of Payload) 8016.

A reserved area (Reserved) 8011 is a reserved area, and is set to 0.

The encryption method (C_A) 8012 indicates the encryption method of the payload portion, and clearly indicates, for example, that encryption is performed with AES having a key length of 128 bits and the key type to be applied.

The encryption mode (E-EMI) 8013 indicates the encryption mode of the payload portion, and is used for calculating the content key together with the random value (Nc) 8015.

In the exchange key label (Exchange_Key_Label) 8014, a label for specifying the key exchanged in the authentication process (described later) is set.

In the payload size (Byte Length of Payload) 8016, the payload size of the packet is set.

The payload portion 802 is a portion that stores encrypted content.

As shown in FIG. 7B (a), the content transmission packet 900 related to the encryption process II is a data packet extended corresponding to the extended copy control information, and includes a header portion 901 and a payload portion 902.

As shown in FIG. 7B (b), the header portion 901 includes a payload type (P_T) 9017, a reserved area (Reserved) 9011, an encryption method (C_A) 9012, an encryption mode (E-EMI) 9013, an exchange key label ( (Exchange_Key_Label) 9014, random number value (Nc) 9015, and payload size (Byte Length of Payload) 9016.

The payload type (P_T) 9017 is an identifier indicating whether the payload is content or extended copy control information. For example, 0 is set for content and 1 is set for extended copy control information.

A reserved area (Reserved) 9012 is a reserved area, and is set to 0. The other parts are the same as the header part of the conventional content transmission packet.

The payload portion 902 is composed of encrypted content or encrypted extended copy control information (described later).

The encryption mode (EEMI) 9013 when the payload portion 902 is extended copy control information may be the same as that set for the content, or may be a different value.

When this format is used, the encryption method of the payload portion 902 is encrypted using a content key generated based on an exchange key, an encryption mode (E-EMI) 9013, and a random value (Nc) 9015.

Further, for example, by hashing the extended copy control information and using the exclusive OR with the random value (Nc) 9015 included in the header portion of the content packet as the content encryption key, the value of the extended copy control information By correlating the content key for encrypting the content, it is possible to prevent falsification of the extended copy control information even if the extended copy control information is transmitted without being encrypted.

As shown in FIG. 7C (a), the extended copy control format is composed of Type 1001, Length 1002, and extended copy control information 1003.

Type 1001 is an ID indicating the type of extended copy control information, and is used to identify the format of the extended copy control information of the packet.

Length 1002 indicates the size of the extended copy control information included in the packet.

The extended copy control information 1003 indicates copy control information of the content. For example, as shown in FIG. 7C (b), Retention_Move_Mode10031, Retention_State10032, EPN10033, DTCP_CCI10034, Image_Constrain_Token10035, APS10036, Copy1Tun, Copy1 Composed.

Retention_Move_Mode 10031 is an entry indicating whether or not temporary storage is possible.

Retention_State 10032 is an entry indicating a temporary accumulation time.

EPN10033 is an entry indicating whether or not unlimited copy operation with output protection is possible.

DTCP_CCI10034 is an entry indicating copy control information defined by the DTCP method.

Image_Constraint_Token 10033 is an entry indicating whether or not the video output signal is restricted.

APS10036 is an entry indicating analog output copy control information.

Copy_Count 10037 is an entry indicating the number of copies.

Time_Span10038 is an entry indicating the viewing time limit.

Image_Convert_Constrain 1000039 is an entry indicating whether or not change (for example, down-conversion) of the resolution, screen size, luminance range, etc. of the received content is permitted.

In the packet for transmitting the extended copy control information, the first bit of the data is handled as an identifier for identifying the extended copy control information transmission packet and the content transmission packet. In the case of the extended copy control information, the identifier is set to 1. For example, the header is configured from Type 1001 and Length 1002 in the configuration example of FIG. 7C instead of the format illustrated in FIG. 7B, which is similar to the content transmission packet format, as long as it can be distinguished from the content transmission packet format in FIG. 7A. The payload portion may be composed only of the extended copy control information 1003.

By transmitting the extended copy control information in the format as described above, for example, copy control information not currently defined by the DTCP-IP system can be easily transmitted in a form independent of the content format. Further, according to this format, it is possible to easily distinguish whether a packet is content or extended copy control information, and it is possible to easily add or change copy control information.
When content is transmitted using HTTP (Hypertext Transfer Protocol) using the format shown in FIG. 7B, the content is transmitted in the format shown in FIG. 7D, for example. Here, TCP is used as the transport layer protocol, but the TCP header is omitted. Note that RTP (Real-time Transport Protocol) may be used instead of HTTP.
Transmission data 1100 in the case of transmitting content using the format shown in FIGS. 7B and 7C includes an HTTP header 1101, an extended copy control information transmission packet 1110, and a content transmission packet 1120.

The extended copy control information transmission packet 1110 includes an extended copy control information header part 1111 and a payload part (extended copy control information) 1112. The extended copy control information transmission packet 1110 may include one or more packets in the transmission data 1100. For example, a different extension copy control information transmission packet 1110 may be included for each service / channel such as a content provider or broadcasting station, or for each content type (2K content, 4K content, 8K content, etc.).

The content transmission packet 1120 includes a content header portion 1121 and a payload portion (content) 1122.

The extension copy control information header portion 1111 is a header portion in which the payload type (P_T) 9017 is set to 1 in the header portion of the content transmission packet shown in FIG. 7B.

The payload portion (extended copy control information) 1112 includes an exchange key exchanged in a device authentication process (described later) between the content transmitting device and the content receiving device, and an encryption mode (set in the extended copy control information header portion 1111). Extended copy control information encrypted based on information such as EEMI) 9013 and random number (Nc) 9015 is stored.

The extended copy control information 1003 may include not only the configuration example shown in FIG. 7C but also information of a plurality of formats at the same time.

The extended copy control information transmission packet 1110 indicates copy control information of content to be transmitted thereafter, and is inserted into transmission data at least every time the content copy control information changes.

The content header portion 1121 is a header portion in which the payload type (P_T) is set to 0 in the header portion of the content transmission packet shown in FIG. 7B.

The payload portion (content) 1122 includes an exchange key exchanged in a device authentication process (described later) between the content transmitting device and the content receiving device, an encryption mode (E-EMI) 9013 set in the content header portion 1121, Content encrypted based on information such as a random value (Nc) 9015 is set.

Next, a table group related to device information will be described with reference to FIGS. 8A to 8C.
FIG. 8A is a diagram illustrating an example of a device information definition table.
FIG. 8B is a diagram illustrating an example of a device control information table.
FIG. 8C is a diagram illustrating an example of a device information table.

The table group related to the device information includes a device information definition table 5100, a device control information table 5200, and a device information table 5300. The storage device of the content transmission device (for example, the flash memory 150 in the case of the smartphone 100 in FIG. 2). Stored in

The device information definition table 5100 is a table for defining various constants related to devices for content transmission. As shown in FIG. 8A, the device authentication maximum number 5101, the counter maximum value 5102, the simultaneous access maximum number 5103, The maximum access number (4K / 8K) 5104 is used.

The maximum device authentication number 5101 is a field indicating the maximum number of device authentications that can be performed between the content transmission device and the content reception device during device authentication processing (described later).

The maximum counter value 5102 is a field indicating the maximum counter value that is valid for the authentication process.

The simultaneous access maximum number 5103 is a field indicating the maximum number of devices that simultaneously permit access requests for content of 2K or less.

The maximum number of simultaneous accesses (4K / 8K) 5104 is a field that indicates the maximum number of devices that simultaneously permit access requests for 4K / 8K content with higher image quality.

The device control information table 5200 illustrated in FIG. 8B is a table that stores information used to control devices.
The exchange key 5220 is a field for storing key information used in encryption / decryption processing when content is transmitted between the content transmitting device and the content receiving device and its additional information (label, key type, etc.).

The number of authenticated devices 5221 is a field for storing the number of content receiving devices that have been authenticated with the device itself. When this value reaches the device authentication maximum number 5101, the content transmission device does not execute the subsequent device authentication processing or does not accept the device authentication request from the content receiving device.

Similarly, when the value of the simultaneous access number 5222 and the simultaneous access number (4K / 8K) 5223 reaches the simultaneous access maximum number 5103 and the simultaneous access maximum number (4K / 8K) 5104, the content transmitting apparatus The content output is not executed, or subsequent content transmission requests from the content receiving apparatus and the user are not accepted.

The device information table 5300 is a table for storing information of a device that transmits content. As shown in FIG. 8C, an ID 5301, a device ID 5302, address information 5303, an authentication counter value 5304, a transmission status 5305, a manufacturer name 5310, format 5311, device type 5312, resolution 5320, HDR 5321, HDCP version 5322, input terminal number 5323, output terminal number 5324, encryption standard version 5330, terminal number 5331, wireless standard 5332, and speed 5333.

ID 5301 is a field indicating the registration number of the table.

The device ID 5302 is a field for storing an identifier for uniquely identifying each device. The device ID 5302 is generated by a specific authentication authority or license management authority, and is stored in the nonvolatile memory in advance when each device is manufactured, or is recorded in the nonvolatile memory safely after executing a specific registration process after purchase. And has a unique value for each device. The device ID 5302 may include information such as a public key in addition to the manufacturing serial number.

Address information 5303 is a field for storing the IP address (IPv4 / IPv6) and MAC address of each device on the network. The IP address may be limited to an address form that is assumed to be used at home, such as a private address or a local address.

The authentication counter value 5304 is a field for storing the current value of the authentication counter of the corresponding device.

The transmission status 5305 is a field for storing a content transmission status (for example, being accessed or stopped) to the content receiving device.

The manufacturer name 5310 is a field for storing the manufacturer name of this device.

A format 5311 is a field for storing the model number (model number) of the device.

The device type 5322 is a field for storing a category as a digital device such as a television receiver, a smartphone, a tablet, or a PC.

The resolution 5320 to the number of output terminals 5324 are information relating to the HDMI interface (HHDMI output unit 118 in FIG. 2, HDMI input / output unit 206 in FIG. 3, HDMI input unit 306 in FIG. 4) of this device. In the resolution 5320, the resolution related to the display of this device is stored. In the case of Full HD (2K), a value indicating “1080i”, “1080p”, or “2160p” is stored in the case of 4K. The HDR 5321 is a field for storing presence / absence of HDR support. HDR (High Dynamic Range) is a technique for synthesizing a plurality of images with different exposures in video expression and expanding the range in which gradation can be expressed. The HDCP version 5322 is a field for storing the HDCP version installed in the corresponding HDMI interface. The number of input terminals 5323 and the number of output terminals 5324 are fields for storing the number of HDMI input terminals and the number of HDMI output terminals, respectively.

Encryption standard version 5330 to speed 5333 are information relating to the network of this device. The encryption standard version 5330 is a field for storing the encryption standard version to be used during transmission over the network. The terminal number 5331 is a field for storing the number of Ethernet (registered trademark) terminals in the wired LAN. The wireless standard 5332 is a field for storing a wireless standard supported by this device, and stores a value representing a standard such as “IEEE802.11b / g / n / ac”. The speed 5332 is a communication speed in the network, and stores a value representing a speed such as “100 Mbps / 1 Gbps”.

Next, control information associated with content will be described with reference to FIGS. 9A to 9C.
FIG. 9A is a diagram illustrating an example of a content usage descriptor.
FIG. 9B is a diagram illustrating an example of a digital copy control descriptor.
FIG. 9C is a diagram illustrating an example of the down-conversion restriction descriptor.

The content usage descriptor 1200, the digital copy control descriptor 1300, and the down-conversion restriction descriptor 1400 are added to the content distributed by the content provider of the broadcast station 5 or the content providing server 6, and describe information describing the usage limitation of the distributed content. It is. The device that receives this content refers to when handling such information (whether or not to output to another device, whether or not the output content is encrypted, encryption mode, and recording control).

The content usage descriptor 1200 is set in, for example, SDT (Service Description Table) or EIT (Event Information Table) of SI (Service Information: program arrangement information).

The content usage descriptor 1200 indicates information for controlling the recording of received content and output to other content receiving devices, and the content provider (for example, the copyright owner of a broadcast station, content service provider, etc.) This is information added to control recording / output for the content. The content use descriptor 1200 is used in combination with a digital copy control descriptor 1300 and a down-conversion restriction descriptor 1400 described later.

9A, the content usage descriptor 1200 includes a copy restriction mode (copy_restriction_mode) 1201, a resolution restriction bit (image_constraint_token) 1202, a temporary accumulation control bit (retention_mode) 1203, a temporary accumulation allowable time (retention_state) 1204, and an output. It has a protection bit (encryption_mode) 1205, a remote access restriction mode (remote_access_restriction_mode) 1206, and a downconvert restriction mode (downconvert_restriction_mode) 1207. Note that the configuration of the content usage descriptor 1200 may include other information, and is not limited to this configuration example.

A copy restriction mode (copy_restriction_mode) 1201 indicates a copy number restriction mode, and is defined by the operation rules of the content provider. For example, when this value is “0”, it means that the number of copies is operated, and when it is “1”, it is not used. If this information is not included (not arranged), it is assumed that “1” is set as a default.

The resolution restriction bit (image_constraint_token) 1202 is information indicating whether or not there is an image quality restriction of the video signal output from the digital video / audio output terminal 116. For example, when this value is “0”, the resolution of video / audio output is limited, and when it is “1”, no limitation is performed.

The temporary storage control bit (retention_mode) 1203 is information indicating whether or not temporary storage of content received under conditions is permitted. For example, when this value is “0”, temporary storage is possible even if a digital copy control descriptor 1300 described later is “copy prohibited”, and when it is “1”, temporary storage cannot be performed. .

A temporary storage allowable time (retention_state) 1204 indicates a temporary storage allowable time after the content is received. For example, information such as no limit, 1 hour 30 minutes, 3 hours, 1 day, 1 week, and the like is set.

The output protection bit (encryption_mode) 1205 is information indicating the presence or absence of output protection when a digital copy control descriptor 1300 (to be described later) outputs “contents that can be copied without restrictions” from the digital input / output terminal 114. For example, when this value is “0”, output protection processing is performed. When this value is “1”, output protection processing is not performed.

A remote access restriction mode (remote_access_restriction_mode) 1206 indicates a mode for restricting the use of received content from a terminal outside the house such as a place where the user is away or by a user's house, and is defined by the operation regulations of the content provider. For example, when this value is “0”, use in remote access is prohibited, and when it is “1”, it means no restriction. By using this value in the subsequent processing, the content provider can restrict remote access to the content.

The down-conversion restriction mode (downconvert_restriction_mode) 1207 is information indicating whether or not down-conversion is permitted for content resolution, screen size, luminance range, and the like. For example, when “1”, down-conversion is prohibited, and when “0”, down-conversion is allowed.

The digital copy control descriptor 1300 indicates information for controlling the copy generation in the digital recording apparatus. When digital copying and analog copying are performed, a content provider (for example, a copyright owner such as a broadcasting station or a content service provider) is provided. Is information added to convey information about recording / copying of the content to the recording apparatus.

The digital copy control descriptor 1300 includes digital copy control information (digital_recording_control_data) 1301, copy control format information (copy_control_type) 1302, and analog output copy control information (APS_control_data) 1303, as shown in FIG. 9B. The configuration of the digital copy control descriptor 1300 may include other information, and is not limited to this configuration example.

Digital copy control information (digital_recording_control_data) 1301 is information for controlling the copy generation of the received content. For example, when this value is “00”, “copying is possible without constraint”, “01” and “11” are “copy prohibited”, and “10” is “copying is possible for only one generation”.

Copy control format information (copy_control_type) 1302 is information in a format for controlling the copy generation of the received content. For example, when this value is “01”, the content is encrypted using an encryption method (for example, DTCP, DTCP-IP, Windows Media DRM, etc.) designated by the content provider, and the digital input / output terminal 114, and in the case of “11”, the data is output from the digital input / output terminal 114 without being encrypted.

Analog output copy control information (APS_control_data) 1303 is information for controlling analog output copying when the value of the digital copy control format information 1301 is “01” or “11”. For example, when this value is “00”, copying is possible without any constraint condition, and when the value is other than this, copying is restricted by some constraint condition.

The down-conversion restriction descriptor 1400 is information describing conditions when content is down-converted. As shown in FIG. 9C, the down-conversion target content (downconvert_objection) 1401, down-conversion restriction date / time (downconvert_restriction_date) 1402, simulant It consists of program information (simul_program_information) 1403 and a downconvert condition (downconvert_condition) 1404.

The down-conversion target content (downconvert_target_content) 1401 is information regarding the condition of the content to be down-converted. For example, information such as “resolution 1920 × 1080 (1080p) and HDR support” and “resolution of 3840 × 2160 (2160p) or higher” is stored.

The down-conversion restriction date / time (downconvert_restriction_date) 1402 is information relating to the date / time when down-conversion is performed. For example, information “down conversion is prohibited until 2018/3/31” and “down conversion is permitted after 2018/4/1” is stored.

Simul program information (simul_program_information) 1403 is distribution information of content to be down-converted. For example, it is distributed simultaneously on a broadcast wave, “distributed at the same time with a 2K tuner”, or distributed by streaming, by accessing “URL: http://www.aaa.co.jp” Information that can be viewed from an Internet browser is stored.

The down-conversion condition (downconvert_condition) 1404 is information relating to a range up to which conversion is possible when content down-conversion is permitted. For example, if the content to be down-converted is HDR-compatible, “If it is an HLG (Hybrid Log-gamma) method, it can be changed to SDR (Standard Dynamic Range) or LDR (Low Dynamic Range), but the HDR10 method cannot be changed”. Or information such as “change to resolution 720 × 480 or 720 × 576 is not possible” is stored.

In addition to the above, a configuration including the number of copies when down-conversion is permitted and the number of simultaneous outputs that limit the number of outputs to other devices may be used.

Next, a control table that the content transmitting device and the content receiving device refer to when outputting or recording content will be described with reference to FIGS. 10 and 11.
FIG. 10 is a diagram illustrating an example of a digital content output control table.
FIG. 11 is a diagram illustrating an example of a digital content recording control table.

The digital content output control table 1500 is a table showing the constraint conditions when outputting from the content transmitting apparatus and the operation at that time. As shown in FIG. 10, the copy control format information (copy_control_type) condition 1501, the digital copy control The column includes an information (digital_recording_control_data) condition 1502, an output protection bit (encryption_mode) condition 1503, a down-convert restriction mode (downconvert_restriction_mode) condition 1504, and an output operation 1505.

The copy control format information (copy_control_type) condition 1501 and the digital copy control information (digital_recording_control_data) condition 1502 are conditions related to the entry of the digital copy control descriptor 1300 shown in FIG. 9A. The output protection bit (encryption_mode) condition 1503, down-conversion The restriction mode (downconvert_restriction_mode) condition 1504 is a condition related to the entry of the digital copy usage descriptor 1200 shown in FIG. 9A and is information added to the content distributed from the broadcast station 5 or the content providing server 6.
When these conditions are satisfied, the output operation 1500 describes whether or not digital content can be output from the digital output terminal of the content transmitting apparatus that has received the content from the broadcast station 5 or the content providing server 6, whether or not it is encrypted, and the encryption mode. It means to do the operation. Here, the digital output terminal is a concept including all terminals that transmit digital data wirelessly, such as an Ethernet standard terminal, an HDMI terminal, and other digital data output terminals.

For example, when the copy control format information condition 1501 is “01”, the digital copy control information condition 1502 is “00”, and the output protection bit condition 1503 is “1”, the content is output from the digital output terminal without encryption as an output operation. When the copy control format information condition 1501 is “01”, the digital copy control information condition 1502 is “01”, and the down-conversion restriction mode condition 1504 is “0”, copying is not permitted. It shows that the received content can be down-converted, encrypted and output from the digital output terminal.

Note that when down-converting, the content transmission apparatus is also bound by the requirements defined in the down-conversion restriction descriptor 1400 shown in FIG. 9C.

The digital content recording control table 1600 is a restriction condition and operation at the time when the digital device that records the digital content including the content transmitting device and the content receiving device records the content in the recording device and outputs the sound. As shown in FIG. 11, the copy control format information (copy_control_type) condition 1601, the digital copy control information (digital_recording_control_data) condition 1602, the output protection bit (encryption_mode) condition 1603, the down-conversion restriction mode (downconvert_restriction_mode) condition 1604, a recording control operation 1605, and an audio output operation 1606.

The copy control format information (copy_control_type) condition 1601 and the digital copy control information (digital_recording_control_data) condition 1602 are conditions related to the entry of the digital copy control descriptor 1300 shown in FIG. 9A, and include an output protection bit (encryption_mode) condition 1603, down-conversion. The restriction mode (downconvert_restriction_mode) condition 1604 is a condition related to the entry of the digital copy usage descriptor 1200 shown in FIG. 9A. The content receiving device and the content transmitting device refer to these conditions and execute recording control of the digital content input from the digital input terminal. Similarly, it means that the operation described in the audio output operation 1606 is performed regarding the audio output of the digital content input from the digital input terminal.

For example, when the copy control format information condition 1601 is “01”, the digital copy control information condition 1602 is “00”, and the output protection bit condition 1603 is “1”, the content input from the digital input terminal is recorded without being encrypted. When the copy control format information condition 1601 is “01”, the digital copy control information condition 1602 is “01”, and the down-conversion restriction mode condition 1604 is “0”, recording is prohibited. It shows that the content can be output as audio by encryption and down-conversion is also possible at that time.

Next, processing when content is transmitted from the content transmission device to the content reception device will be described with reference to FIGS.
FIG. 12 is a flowchart when content is transmitted from the content transmission device to the content reception device.
FIG. 13 is a sequence diagram of the device information acquisition process.
FIG. 14 is a sequence diagram of device authentication processing.
FIG. 15 is a diagram illustrating an example of a user interface that displays device information.
FIG. 16 is a diagram illustrating an example of a user interface of the content viewing / transmission application.

The content transmission device acquires information about the content that can be viewed or output by the device itself by launching an application or selecting a function to view the content as needed, and displays the content list screen on an internal or external monitor To do. For example, in the case of the smartphone 100, the content includes content being received or scheduled to be received by the tuner 112, content being received or scheduled to be received by the wireless LAN 106, and content recorded in the main memory 104 or the flash memory 230. The user selects content to be viewed from the displayed content list screen using the touch panel 124 or the input unit 270/370 (S00).

Next, a monitor for viewing the content selected in S00 is selected using the monitor identification program 152. First, information on a nearby content receiving device is acquired by one or more communication means such as a wired LAN (Ethernet), a wireless LAN (WiFi), near field communication (Bluetooth), and a distance image sensor 144 (S01). The device information acquisition process S01 uses, for example, a mechanism of UPnP (Universal Plug and Play) or DLNA (Digital Living Network Alliance). This device information acquisition process S01 will be described in detail later with reference to FIG.

Next, the content transmission apparatus displays the acquired device information on a built-in or external monitor screen (S02). An example of displaying the device information will be described later in detail by taking the case of the smartphone 100 as an example.

The user designates the content receiving device using the touch panel or the input unit (S02), and instructs the transmission of the content (S03). At this time, the content transmitting apparatus instructs the content receiving apparatus designated using a protocol such as DLNA to receive the content as necessary.

Next, a predetermined device authentication process is performed between the content transmitting device and the content receiving device using the device authentication program (S04). This device authentication process S04 will be described in detail later with reference to FIG.

Next, the content transmitting apparatus refers to the format of the content selected in S00, and determines whether the content is 4K / 8K content (S05). Here, the information regarding the format of the content is included in a code control descriptor (video_decode_control_descriptor) in, for example, a video in a PMT (Program Map Table) in the MPEG system.

If the content is not 4K / 8K content (S05: NO), the digital content output control table 1500 of the content is referred to and it is determined whether or not the content can be output. And only when it can output, it transmits to a content receiver. Here, processing when encryption is required at the time of output using an encryption / decryption program will be described. If the device authentication process executed in S404 is an authentication algorithm for 2K content, encryption is performed based on the key information shared with the content receiving apparatus using the encryption process I407b, and the process shown in FIG. Send in the format described. On the other hand, if the device authentication process is an authentication algorithm for 4K / 8K content, encryption is performed based on key information shared with the content receiving apparatus using the encryption process II 407a, and is described in FIG. 7B. The transmitted format is transmitted (S07).

When the content is 4K / 8K content (S05: YES), it is determined by referring to the information acquired in S01 whether or not the content receiving device that is the content transmission target supports 4K / 8K content. Further, the content transmission apparatus determines whether the authentication algorithm used for the device authentication process in S04 is for 2K content or 4K / 8K content (S06). For example, even if 4K / 8K is supported in the information acquired in S01, it is determined that 4K / 8K content is not supported when an authentication algorithm for 2K content is used in S04. Although not shown, a sequence for reporting the resolution supported by the content receiving device to the content transmitting device may be provided during the device authentication process.

When 4K / 8K content is supported (S05: YES), the digital content output control table 1500 of the content is referred to and it is determined whether output is possible. And only when it can output, it transmits to a content receiver. Here, when encryption is necessary at the time of output using the encryption / decryption program, encryption is performed based on the key information shared with the content receiving device using the encryption processing II 407a, and is described in FIG. 7B. The transmitted format is transmitted (S07).

When the 4K / 8K content is not supported (S05: NO), it is determined whether there is a 2K simultaneous broadcast program (S08). This can be confirmed by the simultaneous program information 1403 of the down-conversion restriction descriptor 1400 in FIG. 9C.

When there is a program that is being broadcast simultaneously (S08: YES), it is determined whether or not output is possible by referring to the digital content output control table 1500 of the content of that program. And only when it can output, it transmits to a content receiver. Here, when encryption is necessary at the time of output, encryption is performed based on key information shared with the content receiving apparatus using the encryption processing I407b, and the encrypted information is transmitted in the format described in FIG. 7A (S13). ).

When there is no program broadcast simultaneously (S08: YES), it is determined whether or not the down-conversion restriction mode 1207 of the content usage descriptor 1200 in FIG. 9A is permitted to be down-converted (S09).

When down-conversion is not permitted (S09: NO), the content transmission device displays an error message indicating that the content cannot be transmitted on the built-in or external monitor screen (S12).

When down-conversion is permitted (S09: YES), the content transmission apparatus performs down-conversion processing for changing the resolution, screen size, luminance range, etc. of the content using the down-conversion program and the down-conversion unit 404 (S10). ), The content obtained by re-compressing the down-converted content by the encoding unit 408 is transmitted to the content receiving device. Here, when encryption is necessary at the time of output, encryption is performed based on key information shared between the content receiving apparatus using the encryption / decryption program and encryption processing I407b, and the format described in FIG. 7A (S11).
Here, the content transmission instruction S03 and the device authentication processing S04 may be performed after S05 for determining whether or not the content is 4K / 8K content.

Next, the device information acquisition process will be described with reference to FIG. This process is executed by using the CPU 102 and the device information management program 160 of the content transmitting device, and the CPU 202 and the device information management program 240 of the content receiving device.

The content transmitting apparatus makes a device information request to the content receiving apparatus (S100). At this time, the content transmission apparatus may use a plurality of interfaces and various protocols provided in parallel. For example, even if device information is acquired via a wireless / wired LAN and a short-range wireless unit (Bluetooth) using the DLNA mechanism, monitor detection is performed using a distance image or a color image acquired by a distance image sensor or camera. good.

In response to the device information request, the content receiving apparatus transmits information such as manufacturer name / format / device type (S102). In addition, a URL (Uniform Resource Locater) provided by the manufacturer may be included.

Next, the content transmitting apparatus makes a digital interface information request to the content receiving apparatus (S104).

The content receiving apparatus receives the digital interface information request and transmits the digital interface information (S106). The digital interface information includes, for example, the resolution, the presence / absence of HDR support, the HDCP version, the number of input terminals, the number of output terminals, etc. in the case of HDMI, and the version of encryption processing, the number of terminals, and the wireless standard in the case of LAN. , Speed and so on.

Here, the information requests of S100 and S104 may be combined into one request. There is also a method for acquiring detailed information by acquiring Web information provided by each manufacturer using a wired / wireless LAN instead of issuing S104 after acquiring the manufacturer name / model / URL information in S100. .

Next, device authentication processing will be described with reference to FIG. This processing is executed using the authentication unit 406 and the device authentication program 158 of the content transmission device, and the authentication unit 426 and the device authentication program 238 of the content reception device.

In this embodiment, first, the content receiving apparatus requests authentication from the content transmitting apparatus (S601). In the authentication request process, the content receiving apparatus attaches the device-specific information including the device ID, the version of the encryption process (standard of encryption process I or encryption process II), and a certificate for the apparatus-specific information to the authentication request. To the content transmission device. Service type (predetermined service level, paid / free, etc.) and content type (resolution level such as SD / HD / Full HD / UHD, genre such as news / sports / movie, etc.) instead of encryption version Or a setting value defined by a predetermined protocol may be included.

The content transmission device receives the authentication request and sends a reception confirmation to the content reception device (S602). At that time, it is confirmed whether or not the value of the authentication device number 5221 in the device control information table 5200 is less than the maximum number of authentication devices 5101 in the device information definition table 5100. The processing is continued, and if the maximum number of authentication devices 5101 has been reached, the processing ends after transmitting an error reception confirmation.
Next, after confirming whether the encryption processing designated by the content receiving apparatus is encryption processing I or encryption processing II, and determining an authentication algorithm to be used, create an authentication request from one's own side, As in the case of the content receiving apparatus in S601, the unique information of the content transmitting apparatus and its certificate are attached and sent to the content receiving apparatus (S603).

The content receiving apparatus receives the authentication request and sends a reception confirmation to the content transmitting apparatus (S604).

Next, the content transmission apparatus verifies each information of the authentication request received according to the procedure of the encryption process I or the encryption process II, and attaches parameters necessary for generating different key information in the encryption process I and the encryption process II. An authentication response is sent to the content receiving device (S605).

After receiving the authentication response and sending the receipt confirmation to the content transmitting device (S606), the content receiving device creates an authentication response from its own side and is necessary for generating key information as in the case of the content transmitting device. An authentication response with parameters is sent to the content transmission apparatus (S607), and an authentication key common to the content transmission apparatus is generated using necessary parameters.

Next, the content transmitting apparatus receives an authentication response and sends a reception confirmation to the content receiving apparatus (S608), and generates an authentication key common to the content receiving apparatus using necessary parameters, as in the case of the content receiving apparatus.
Thereafter, in order to confirm whether or not the content receiving device is a device existing in the home, the content transmitting device starts a timer and then transmits a home confirmation execution request to the content receiving device (S615). In response to this, the content receiving apparatus sends the reception confirmation to the content transmitting apparatus (S616). Upon receipt of the reception confirmation, the content transmission apparatus stops the timer, and the measurement value (T1) from when the in-home confirmation execution request is issued until the reception confirmation is received does not exceed a predetermined value (T) Confirm. When measurement value (T1) ≦ predetermined value (T), it is determined that the content reception device is in the house and is in a range of personal use. On the other hand, if measured value (T1)> predetermined value (T), it is determined that there is a possibility that the content receiving apparatus exists outside the home, and the subsequent processing is interrupted to end the device authentication processing. Through the procedure so far, the authentication unit 406 of the content transmission device and the authentication unit 426 of the content reception device generate and share a common authentication key.

Next, the content transmission device generates an exchange key to be used when encrypting the content, encrypts the exchange key using the generated authentication key, and sends it to the content reception device together with an ID for identifying the exchange key. Send (S609). Here, it is assumed that the encryption process I and the encryption process II generate exchange keys having different key lengths and calculation methods.

Then, the content receiving device decrypts the exchange key transmitted from the content transmitting device using the previously generated authentication key, and sends a reception confirmation (S610).

Next, when receiving the reception confirmation, the content transmission apparatus registers information related to the content reception apparatus in the device information table 5300 illustrated in FIG. 8C (S621).

By the processing procedure shown in FIG. 14 above, the content transmission device and the content reception device can share a common exchange key. The exchange key is set in the exchange key 5220 in the device control information table 5200 of FIG. 8B together with the additional information related to the exchange key, and is used to generate a common key for encrypting / decrypting the content.

Here, only when the device authentication process is successful, the content transmission apparatus permits subsequent content encryption and output. At that time, refer to the number of simultaneous accesses 5222 in the device control information table 5200 for contents that require encryption processing I, and refer to the number of simultaneous accesses (4K / 8K) 5223 for contents that require encryption processing II encryption. It was confirmed whether or not these values were less than the maximum number of simultaneous accesses 5103 or the maximum number of simultaneous accesses (4K / 8K) 5104 in the device information definition table 5100. Output only in cases.

Further, the content transmission apparatus may determine the authentication algorithm performed in S603 after receiving the authentication request in S601.

Further, when the content requested to be transmitted is 4K / 8K content and down-conversion is prohibited, if the encryption processing designated by the content receiving apparatus in S603 is encryption processing I, the subsequent processing is performed. You may end.

Next, a user interface when the smartphone 100 is a content transmission device will be described with reference to FIGS. 15 and 16.
As an example of the content device information display shown in S02 of FIG. 12, the smartphone 100 in FIG. 15 sends the device information and the content to be transmitted to the content transmission application (hereinafter, application software in the smartphone 100 is simply referred to as “application”). An example where the title is displayed is shown.

The user confirms the device information (manufacturer / device type / format / destination content support) displayed in the receiving device display area 701 and taps with his / her finger to mark the radio button 703 and display the content. Can be selected.

Further, it is possible to select the content displayed in the transmission content display area 702 by confirming the title of the content and tapping with a finger. Thereby, the title of the selected content is displayed in luminance.

The user taps the transmission button 710 when transmitting the title of the selected content to the selected content receiving apparatus.

Further, as another user interface at the time of content transmission, as shown in FIG. 16, a user interface that allows viewing of content and is easy to operate visually and intuitively can be considered.

The smartphone 100 reproduces content in the viewing area 801. A control bar 802 can be added to the viewing area 801 as shown in the figure.

In the receiving device display area 810, a digital device in the vicinity of the smartphone 100 is displayed as a digital device icon 811. The device icon 811 displays a distance 812 and content support information 813 as accompanying information.

The device information is acquired by the device information acquisition process shown in FIG. 13 by a communication means such as a wired LAN (Ethernet), a wireless LAN (WiFi), or a near field communication (Bluetooth). Further, the smartphone 100 obtains the distance of the nearby digital device by the distance image sensor 144 shown in FIG. 2, acquires an image, recognizes the shape of the device, the model number display character of the device, and the like, By matching with the template information (not shown) of the device prepared in advance, the manufacturer name and format are obtained and matched with the manufacturer name and format acquired by the device information acquisition process. Correspondence with an actual content receiving apparatus can be performed.

Alternatively, the distance may be estimated based on the strength of the radio wave such as wireless LAN (WiFi) or near field communication (Bluetooth), and the digital device icon 811 may be associated with the content reception device for device information acquisition processing.

Further, although not near the content transmission apparatus, the device type and model number are displayed in the WiFi area 820 in order to confirm the devices that can communicate by receiving the WiFi radio wave.

When the user wants to transmit the content to the content receiving apparatus displayed with the digital device icon 811, the user simply drags the viewing area 801 to the device icon 811 (830).

As described above, the content provider can provide high-quality content to the user while easily securing the copyright, and the user can safely secure the appropriate content on the appropriate monitor without exceeding the range of personal use of the content. Can watch.

DESCRIPTION OF SYMBOLS 5 ... Broadcasting station, 6 ... Content provision server, 7 ... Base station, 11 ... Hub, 12 ... Router, 20 ... Wireless access point, 50 ... Tablet, 60 ... Internet, GPS satellite, 80 ... Wired network, 100 ... Smartphone 200 ... Television receiver with built-in recorder, 300 ... Television receiver, 400 ... Notebook computer.

Claims (8)

A content transmission device that transmits content to a content reception device,
First encryption processing means for encrypting the content by first encryption processing;
A second encryption processing means for encrypting the content by a second encryption process different from the first encryption process;
Conversion means for converting the content, and the content has associated down-conversion restriction information,
Receiving from the content receiving device information related to the cryptographic processing of the content receiving device;
If the content receiving device supports the second encryption processing, the content is encrypted by the second encryption processing means, the content is transmitted,
When the down-conversion restriction information is in a state of permitting down-conversion and the content receiving device does not support the second encryption processing, the content is converted so as to conform to the first encryption processing. Then, the content transmission apparatus encrypts the converted content by the first encryption processing and transmits the content. The first encryption process is a process of encrypting low-resolution content with respect to the content targeted by the second encryption process,
2. The content transmission apparatus according to claim 1, wherein the conversion is a process of down-converting the content. Receiving means for receiving device information from the content receiving device;
Display means for displaying information of the received device;
2. The content transmission apparatus according to claim 1, further comprising a transmission unit configured to transmit content to the selected content reception apparatus among the content reception apparatuses corresponding to the displayed information. Holds information about simultaneous broadcasts of content,
When the content receiving apparatus does not support the second encryption process, the information related to the simultaneous broadcast of the content is referred to, and there is a corresponding content simultaneous broadcast in a form suitable for the first encryption process. Whether or not
When there is a simultaneous broadcast of the corresponding content in a form compatible with the first encryption process, the simultaneous broadcast of the content is received, encrypted by the first encryption process, and the content is transmitted. The content transmission apparatus according to claim 1. A content transmission method for transmitting content from a content transmission device to a content reception device,
First encryption processing means for encrypting by the first encryption processing;
A second encryption processing means for encrypting the content by a second encryption process different from the first encryption process;
The content has associated down-conversion restriction information,
Converting the content, and the content transmitting device receives information related to encryption processing of the content receiving device from the content receiving device;
The content transmitting device, when the content receiving device supports the second encryption processing, encrypting by the second encryption processing means, and transmitting the content;
When the down-conversion restriction information indicates a state in which down-conversion is permitted, and the content transmission apparatus does not support the second encryption process, the content transmission apparatus converts the content into the first encryption process. Converting to fit, and
The content transmission method, wherein the content transmission apparatus encrypts the converted content by the first encryption processing and transmits the content. The first encryption process is a process of encrypting low-resolution content with respect to the content targeted by the second encryption process,
6. The content transmission method according to claim 5, wherein the conversion is a process of down-converting the content. The content transmitting device receiving device information from the content receiving device;
Displaying received device information;
6. The content transmission method according to claim 5, further comprising a step of transmitting the content to a selected content reception device among content reception devices corresponding to the displayed information. The content transmission device holds information related to simultaneous broadcasting of content,
When the content transmission device does not support the second encryption processing, the content transmission device refers to the information related to the simultaneous broadcasting of the content and corresponds to the first encryption processing. Determining whether there is simultaneous broadcast of content;
When the content transmission device has a simultaneous broadcast of the corresponding content in a form compatible with the first encryption processing, the step of receiving the simultaneous broadcast of the content; and the content transmission device transmits the received content to the 6. The content transmitting method according to claim 5, further comprising a step of encrypting and transmitting by the first encryption processing.

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