JP6501951B2 - Multimedia content receiver - Google Patents

Description

  The present invention relates to a method of providing a multimedia service, and more particularly, to a method of transmitting breakdown information on a service provided by a service provider providing a broadcast communication integrated service in a heterogeneous network environment.

  The Internet is evolving to broadband, and Internet broadcasts can be provided by organizing multimedia using the general Internet, as well as existing broadcasts using dedicated channels such as terrestrial channels, satellite channels, and cables. ing. Also, by combining existing broadcasting and Internet broadcasting more organically, a broadcast-communications integrated multimedia service that provides various services has emerged as a realistic service.

  Many broadcast service providers (broadcasting companies) can transmit content not only through a dedicated channel but also through the Internet; rather, broadcasts that transmit content only through the Internet without a dedicated broadcast channel Service providers have also emerged. Therefore, whether it is a broadcast company that uses a dedicated channel and is used with the Internet, or a broadcast company that uses only the Internet, the user views the program content by transmitting the program scheduling information to a large number of viewers along with the program content. It is necessary to publicize to people and make it possible for viewers to view with good intentions. Furthermore, by providing a "replay" service via the Internet, it is possible to make it possible to view the content which the viewer could not view at the time of the main broadcast. In existing broadcasting, such type information is called an electronic program guide (EPG), and in the case of Digital Video Broadcasting (DVB) system standard, PSIP (Program and System Information Protocol) In the European system, it is called by SI (Service Information) or the like. Also, in the MPEG-2 system standard widely used in the existing digital TV system, this is called PSI (Program Specific Information). In the North American method, PSI and PSIP are sent together, but the program can be selected by the viewer with only PSIP. In the European system, PSI and SI can be sent together, and the PSI alone can enable program selection, but it also provides various guide information about the program through the SI. In the specification of the present application, such types of information are also referred to as service specific information (SSI).

  Unlike existing broadcasts that use dedicated channels, Internet broadcasts are provided globally, so there is a region where there is a receiver that can receive Internet broadcasts beyond the regional property of existing broadcasts. For example, it is accessible via the Internet anywhere in the world. Therefore, in the case of Internet broadcasting, in order to overcome the regionality of existing broadcasting standards, which are broadly classified into North America, Europe, Japan, etc., they must be provided in a single system unique in the world, and the receiver complexity It is possible to prevent the degree from increasing unnecessarily. From such a point of view, SSI further requires standardization of a single method.

  Future broadcast and communication integrated broadcasting systems are expected to be reorganized centering on the Internet. That is, not only the program content via the existing broadcast channel but also guide information on the program content via the Internet are stored together in the SSI in a machine-readable format and transmitted. The receiver acquires such SSI via a broadcast channel or the Internet and utilizes it to control broadcast reception so that it can be displayed in a form that can be read by the viewer as needed. Internet broadcasters that do not use a dedicated broadcast channel naturally transmit SSI via the Internet.

  Therefore, there is a need for an apparatus and method for providing a format for transmitting service breakdown information on services provided by a service provider providing broadcast and communication integrated services in an environment of heterogeneous networks including the Internet.

  The information is presented as background information to help understand the description of the present invention. Neither determination nor any mention can be made as to whether it can be applied as prior art related to the present invention.

  The features of the present invention solve at least the aforementioned problems and / or disadvantages and provide at least the advantages described below. Accordingly, an object of the present invention is to provide a format for a service provider providing broadcast and communication integrated services to transmit breakdown information on services provided by itself in the environment of heterogeneous networks including the Internet. .

  According to one aspect of the invention, there is provided a method of receiving a multimedia service. The method includes the steps of receiving service breakdown information on at least one multimedia service provided from different networks, referencing one of the service breakdown information, and selecting one service, and selecting the selected service. And a process of receiving. The service breakdown information may include a first service map table (Service Map Table) including information on at least one service transmitted via a plurality of logical channels, and at least one service transmitted via one logical channel. It may also include one of a second service map table that contains information about the service. Each of the first service map table and the second service map table may include asset association information.

  According to another aspect of the present invention, there is provided a method of transmitting a multimedia service. The method comprises: transmitting service breakdown information on at least one multimedia service provided from different networks; and transmitting the service requested by the receiver to the receiver with reference to the service breakdown information. And process. The service breakdown information includes a first service map table including information on at least one service transmitted via a plurality of logical channels, and information on at least one service transmitted via one logical channel. It may include at least one of the second service map table. Each of the first service map table and the second service map table may include asset association information.

  According to another aspect of the present invention, there is provided an apparatus for receiving a multimedia service. The apparatus includes a receiving unit that receives service breakdown information on at least one multimedia service provided from different networks, and a control unit that refers to the service breakdown information to select one service. The receiving unit may receive the service selected by the control unit. The service breakdown information includes a first service map table including information on at least one service transmitted via a plurality of logical channels, and information on at least one service transmitted via one logical channel. It may include at least one of the second service map table. Each of the first service map table and the second service map table may include asset association information.

  According to yet another aspect of the present invention, an apparatus for transmitting multimedia services is provided. The apparatus includes: a transmitter configured to transmit service breakdown information on at least one multimedia service provided from different networks; and a controller configured to select a service requested by the receiver with reference to the service breakdown information. Including. The transmitter may transmit the service selected by the controller to the receiver. The service breakdown information includes a first service map table including information on at least one service transmitted via a plurality of logical channels, and information on at least one service transmitted via one logical channel. It may include at least one of the second service map table. Each of the first service map table and the second service map table may include asset association information.

  According to another aspect of the present invention, there is provided a method of receiving a multimedia service. The method comprises the steps of receiving a control message and decoding the control message. The control message may include at least one table. The at least one table may include a table for one or more MPTs corresponding to a package. The table for the MPT may include an asset list belonging to a package.

  According to another aspect of the present invention, there is provided an apparatus for receiving a multimedia service. The apparatus includes a receiving unit that receives a control message, and a decoder that decodes the control message. The control message may include at least one table. The at least one table may include a table for one or more MPTs corresponding to a package. The table for the MPT may include an asset list belonging to a package.

  According to another aspect of the present invention, there is provided a method of transmitting a multimedia service. The method includes the steps of generating a control message and transmitting the generated control message. The control message may include at least one table. The at least one table may include a table for one or more MPTs corresponding to a package. The table for the MPT may include an asset list belonging to a package.

  According to another aspect of the present invention, there is provided an apparatus for transmitting multimedia services. The apparatus includes a control unit that generates a control message, and a transmission unit that transmits the generated control message. The control message may include at least one table. The at least one table may include a table for one or more MPTs corresponding to a package. The table for the MPT may include an asset list belonging to a package.

  Other features, advantages and salient features of the invention will become apparent to those skilled in the art from the following detailed description, taken together with the accompanying drawings.

  According to the present invention, the receiver uses the service breakdown information by applying the format for providing the service breakdown information proposed in the present invention and providing the breakdown information on the service provided by the service provider. Allow the viewer to easily select the broadcast content that he / she wishes to view.

FIG. 5 is a diagram illustrating a structure of service breakdown information (SSI) and system guide information in an existing broadcast using a dedicated physical channel according to an embodiment of the present invention. It is a figure which shows the structure of SSI in the internet broadcast. FIG. 5 illustrates the logical structure of an SSI according to an embodiment of the present invention. FIG. 5 illustrates an example of the use of SSI in an MPEG-2 TS based broadcast. FIG. 5 illustrates S1 signaling structure according to an embodiment of the present invention. FIG. 6 illustrates multimedia reception operation in a receiver according to an embodiment of the present invention. FIG. 6 illustrates multimedia reception operation in a receiver according to an embodiment of the present invention. FIG. 2 illustrates the structure of a transmission device according to an embodiment of the present invention; FIG. 2 illustrates the structure of a receiving device according to an embodiment of the present invention.

  It should be noted that like reference numerals are given to identical or similar components, features and structural features throughout the attached drawings.

  The following description, with reference to the accompanying drawings, is provided to assist in a comprehensive understanding of the embodiments of the present invention as defined in the claims and the equivalents thereof. . Although various specific details are included to facilitate this understanding, these are merely one example. Accordingly, it will be apparent to those skilled in the art that various changes and modifications of the embodiments described herein are possible without departing from the scope and spirit of the present invention. Also, for the sake of clarity and simplicity, specific descriptions of functions and configurations well known to those skilled in the art are omitted.

  The terms and words used in the following description and claims are not limited to the meaning in the literature and are used solely by the inventor to enable a clear and consistent understanding of the present invention. Thus, as defined by the appended claims and their equivalents, the description of the embodiments of the present invention is merely for the purpose of illustration and is not intended to limit the scope of the present invention. Will be apparent to those of ordinary skill in the art.

  Throughout the specification, it is to be understood that the singular forms "a", "an" and "the" include plural referents unless the context clearly indicates otherwise. . Thus, for example, "element surface" includes one or more of such surfaces.

  First, prior to describing the present invention, terms used in the specification are defined as follows. Media service: A service that conveys information using one or more media, eg, audio, video, images, text, graphics, interactive applications, etc.

  Foreground media services: video services, audio services, Electronic Program Guide (EPG) services, Push Video on Demand (VoD) services, portal services, etc. Paid or free media products directly exposed to viewers so that one viewer at a time can select and enjoy.

  Background broadcast service: Assists foreground media services, such as carousel for file download, pre-download via the Internet, etc., but directly to the viewer Unexposed media delivery service.

  Video service: Video is the main service, and accompanying audio is always provided, and audio in other languages, subtitles, interactive applications, other additional data, etc. may be provided.

  Audio service: Audio is the main service, and associated video or images, interactive applications, and other additional data may be provided.

  Interactive application: Called as needed to provide information to the viewer during consumption of the video or audio service, to control the media service in response to the viewer, or to the media operator's server Software that conveys information, collectively referred to as declarative and procedural languages. In connection with the currently consumed video or audio service, it may be called by the media operator or by the media operator regardless of the currently consumed media service. Also, interactive applications already stored in the receiver's cache and recognized by the viewer may be called upon viewer request.

  Regular media: Media that must be provided due to requirements of media service. For example, audio of audio service, or video and audio of video service accompanied by audio.

  Adjunct media: Media that do not have to be provided due to requirements of media services, but are provided as necessary. For example, web documents, widgets, interactive applications, audio clips, video clips, graphics, text, images, supplemental media components, etc. Auxiliary media is always consumed with regular media and can not be consumed alone.

  Media component: A component that constitutes media. For example, in the case of stereoscopic video, there are left-eye video and right-eye video. Also, as another example, in the case of 5.1 channel audio, each channel audio is a media component.

  Auxiliary media component: A media component that can not constitute one media independently, but that constitutes one media together with other media components. For example, in the 2D / 3D time mixed type service, the left eye image is always provided as a 2D image among the left eye and right eye images, and the right eye image provided only in the stereoscopic video section is It is an auxiliary media component.

  Asset: Encoding data for media components. Here, encoding means compression encoding, encoding in accordance with a standard format, and the like.

  Regular asset: Encoding data on media components of regular media. Here, encoding means compression encoding, encoding in accordance with a standard format, and the like.

  Auxiliary asset (adjunct asset): Encoding data on the media component or auxiliary media component of auxiliary media. Here, encoding means compression encoding, encoding in accordance with a standard format, and the like.

  Program: an instance of a media service (e.g. the entire content of one broadcast channel (logical channel)).

  Program item: The content of the program at certain intervals. For example, when a start advertisement, an intermediate advertisement, and a last advertisement are mixed and transmitted in one movie, the content of the time interval corresponding to the movie including the advertisement is included. Here, each advertisement is also an individual program item, but is an embedded program item included in another program item. The program is a result of connecting a plurality of non-inclusive program items (which may include the in-clusive program items) on the time axis.

  Package: Coded data for a program item. It contains control information of multiple assets, transmission, decoding, playback etc of these assets and association.

  Primary asset: A regular asset that may contain synchronization information about auxiliary assets. For example, auxiliary asset synchronization and control information may be included as attached information of M units of the video stream.

  Attached information (attached information): means additional information such as control information and descriptive information about an asset. The adhesion information is a logical term, and is actually included in multiple layers of the transmission hierarchy, in this case called header information.

  Stream type asset (stream asset): An asset in the form of media compression data that can be generated infinitely in time, such as video stream and audio stream.

  Non-stream asset: An asset that does not correspond to a stream asset.

  M unit (M-unit): The next lower component of an asset. M units of stream type assets are the smallest data units that can be input to the media decoder at one time, and the decoding result may be represented by the media at a point in time or for a certain time interval Good. For example, in the case of a video stream, the result of compressing one frame may become one M unit, and in the case of an audio stream, the result of compressing an audio sample for 24 ms becomes one M unit It is also good.

  Logical channel (logical channel): A path for transmitting one encoded program. For example, in an existing digital TV system based on MPEG-2 TS (Transport Stream), a data transfer path specified by a Program Map Table (PMT), or a source address (source address) and a destination address (destination address) on the Internet. , A data transfer path specified by a port number (port number), etc. correspond to a logical channel.

  Physical channel: A path that carries one or more logical channels. For example, terrestrial TV channels or cable TV channels having a bandwidth of 6 MHz, satellite channels, the Internet, etc. correspond to physical channels.

  IP application data flow: One IP application data flow is specified by a source address on the Internet, a destination address, and by a port number in the destination that specifies the application that processes the content of the IP packet. Ru.

  Asset Path Identifier (APID): An identifier of an asset path (for example, information for conveying an asset). One IP application data flow consists of various asset paths, and each asset path is uniquely identified in one IP application data flow by APID.

  Asset Module Identifier (AMID): When an asset is divided into various asset modules and transmitted, it is an identifier that identifies these asset modules within one asset path. For example, if there is a large size table and this table is divided into many sub-tables (sub-tables), if the entire table is designated as one asset, each sub-table becomes an asset module.

  Hereinafter, the format of service breakdown information according to an embodiment of the present invention will be described with reference to the drawings. First, service breakdown information should consider the following requirements.

  Guide information integrity: Service breakdown information (SSI) can be used via media such as all wireless / wireless internet, terrestrial channels, satellite channels, cables, etc. jointly operated by one broadcaster or multiple broadcasters. It is necessary to communicate the breakdown information to the receiver regarding the provided broadcast service.

  Guide Information Format: The SSI should have a machine-readable format that the receiver can efficiently. It is necessary to use a format that can express the same SSI with as little data as possible.

  Guide information target period: SSI needs to guide the breakdown of services past, current, and after a certain period (for example, half a month). However, service breakdowns already broadcast in the past may not be directly included in SSI, in which case the receiver deletes past service breakdowns already stored for a certain period of time (for example, half a month) You may save without doing it.

  Guide Information Valid Period: A specific version of SSI is valid only for a certain period, and needs to be automatically updated by the receiver when a predetermined period ends.

  Organization change support: If necessary, when broadcasting content different from the organization content included in the already known SSI, it is necessary for the transmitter and the receiver to be provided with means for modifying the already known SSI.

  Means of transmitting guide information: It is necessary to transmit the whole or a part of SSI through one or more of mediums such as wired / wireless Internet, terrestrial channel, satellite channel, cable, etc. as needed.

  Optional structure of guide information: Of the SSI content, the information essential to the operation of the broadcasting system is obliged to be transmitted, but the other information needs to have a structure that may be selectively transmitted. . For example, while location information of program content is essential information for the receiver to read the program stream, a plot for program content determines whether the viewer views the program or not. Although it is not always necessary information for the operation of the receiver.

  Minimizing Channel Acquisition Time: The SSI needs to have a structure that can minimize channel acquisition time. Here, "channel acquisition time" means the time until video and audio are played back after applying power or changing channels.

  Forward compatibility with existing broadcasts: SSI should also guide the service breakdown of existing broadcasts based on MPEG-2 TS.

  Backward compatibility with existing broadcasts: It is also necessary to use SSI in existing broadcasts based on MPEG-2 TS. The SSI provided in this way is not used in existing receivers that do not support it, but should not affect its operation. Newer versions of receivers that support SSI can take advantage of SSI.

  Support for multiple small screens in one screen: SSI needs to support multiple small screens in one screen. Here, the space-time positioning function of the small screen is included. For example, when broadcasting a baseball game live, it is necessary to include all of the small screens showing the pitcher, the batter, the specific infielder, the entire stadium, etc. in the entire screen.

  Support for receivers with diverse capabilities: SSI supports content guides for receivers with diverse capabilities, such as mobile devices, SDTV (Standard Definition Television), HDTV (High Definition TV), UHDTV (Ultra-High Definition), etc. There is a need to.

  Guide support for multilingual broadcasts, subtitle broadcasts, screen commentary broadcasts, and sign language broadcasts: SSI has auxiliary content that can improve accessibility, such as audio broadcasts in various languages, subtitle broadcasts, screen commentary broadcasts, and sign language broadcasts. If included in the program, you need to guide this.

  Content Usage Restrictions Guide: SSI needs to guide some restrictions on content usage. Such restrictions may include content rank (no viewing below a certain age), recordability, optional accessibility, fast play / reverse play, pay per view, monthly flat rate charging, and the like.

  Content Data Location Guide: The SSI needs to guide the location of content data. It is necessary to efficiently guide both the case where the entire content is at the same position and the case where the content components are different from one another. In addition, SSI needs to guide the transmission of content using one or more dedicated broadcast physical channels and the Internet alone or in part or all at the same time.

  Guide of Alternative Content Data Location: The SSI needs to guide the location of alternative content data. The alternative content data refers to, for the content selected by the viewer, another position where content identical or similar to the original content data can be read instead of the intended original content data.

  Guides for ancillary data: SSI is not only a guide for the main video and audio, but also the accompanying web documents, widgets, interactive applications, audio clips, video clips, graphics, text, images, partial media streams (eg binoculars It is necessary to guide on auxiliary data such as additional finite-length streams) for representing 3D video over time.

  On the other hand, SSI is provided by broadcaster or broadcaster group. Terrestrial broadcasters, cable broadcasters, satellite broadcasters, Internet broadcasters, etc. operate independently, and therefore independently transmit their service breakdowns unless mutually agreed upon sharing and integrated transmission of service breakdowns. There is only. However, if there is such a promise, the service breakdown may be integrated and guided to a broadcast company group which is a collection of broadcasters who have participated in the promise. If the amount of information in the service breakdown guide is large, it will take a long time to download it at the receiver, so the delay time for the viewer to browse the service breakdown guide will be long, and the modified service breakdown guide will be downloaded Because the burden also increases when you do, a method to overcome such points is required.

  In broadcast systems based on the existing MPEG-2 standard, PSI (Program Specific Information) provided by the MPEG-2 system standard (ISO / IEC 13818-1) is insufficient for the service breakdown guide. Defines and enforces additional service and system guide information. The Advanced Television Systems Committee (ATSC) Program and System Information Protocol (PSIP) and the DVB SI are PSI. In the case of the ATSC PSIP, the receiver contains information that substitutes for the Program Association Table (PAT) and the Program Map Table (PMT) in the MPEG-2 PSI, so that the receiver does not need to decode the PAT and PMT. It is designed to be able to receive

  Unlike broadcasting through dedicated channels that multiplex and transmit many programs in one physical channel, in the case of Internet broadcasting using only the Internet, various programs are not multiplexed in one IP application data flow. That is normal. Of course, if necessary, various programs may be multiplexed in one IP application data flow, but in the scheme proposed by the embodiment of the present invention, one program in one IP application data flow It assumes that only sending. In addition, due to bandwidth limitations of physical channels, the case where program components are divided and transmitted via many different physical channels is not applicable to Internet broadcasting. Under such conditions, SSI for Internet broadcast can be greatly simplified.

  FIG. 1 is a diagram showing the structure of service breakdown information (SSI) in an existing broadcast using a dedicated physical channel according to an embodiment of the present invention.

  The receiver checks the breakdown of physical channels from ATSC PSIP or DVB SI, tunes a specific physical channel, and checks the breakdown of programs in the physical channel from PAT in MPEG-2 PSI. Selecting a particular program allows the receiver to identify program components from the PMT in the MPEG-2 PSI. The ATSC system can also directly identify the components of a particular program from the PSIP information.

  FIG. 2 is a diagram showing the structure of SSI required for Internet broadcasting according to another embodiment of the present invention.

  The receiver can check the program component's path identifier and reproduce the program from the service breakdown information conveyed through the specific path in the same IP application data flow. The service breakdown information needs to be periodically transmitted, since it is impossible to know in advance when the receiver is turned on, when to access this Internet broadcast, and so on. The shorter the cycle, the better. Generally, it is preferable to keep within 500 ms. If the amount of service breakdown information is large, in order to transmit this in a short cycle, it is inefficient because many packets have to be transmitted at the same time interval. Therefore, information transmitted in a short cycle needs to be designed to be as small as possible. The additional guide information may be transmitted with a longer period or otherwise may be conveyed by the request of the receiver.

  FIG. 3 illustrates the logical structure of an SSI according to one embodiment of the present invention. For example, FIG. 3 is a logical structure of SSI for broadcast-communications combined broadcasting using both a dedicated physical channel and the Internet according to an embodiment of the present invention.

  Referring to FIG. 3, the illustrated structure is basically an integrated form of the structures of FIG. 1 and FIG. 2, and SMT-M (Service Map Table for Multiple packages) 301 is through a dedicated broadcast physical channel. The SMT-S (Service Map Table for a Single Package) 309 is used to broadcast a plurality of logical channels, or broadcasts a single logical channel via a dedicated broadcast physical channel or only the Internet. It is used when it is used or broadcasted mainly using the Internet. As an example of broadcasting mainly using the Internet, when a broadcasting company using both a dedicated physical channel and the Internet carries out the Internet broadcasting, data transmitted via the dedicated physical channel can be transmitted by the Internet broadcasting as needed. There is a case to use. For example, due to the limited bandwidth of the dedicated channel, when broadcasting certain content on the Internet, auxiliary data additionally used for this content may share the content to be transmitted via the dedicated channel. In such a case, a receiver that can only access the Internet can not utilize auxiliary data, but a smart TV receiver that has a dedicated channel tuner and an Internet access device is the main content. It can be received via the Internet, and in the case of auxiliary data, received via a dedicated channel, and these can be comprehensively provided to the viewer.

  The SMT-M is a PPT (Package Packing Table) 307-1 to 307 that contains simple guide content on all programs in the physical channel for transmitting SMT-M information and information of each program item currently being broadcasted. -n location reference information, and further includes location reference information and version information on a Package Guide Table (PGT) 305 including guide information on all programs provided by the broadcasting company.

  In order to minimize the channel acquisition time, the SMT is transmitted periodically in a very short period (e.g. 500 ms), so the amount of information contained is also minimized if possible.

  PGT is an amount for a certain period of time (for example, a half month in the past and a future based on the present) out of all the program items that are serviced through all physical channels operated by one broadcaster and the Internet The information content is significantly larger than that of the SMT, and the transmission cycle is also much longer (for example, one minute). The PGT may be downloaded to the receiver via the Internet, if necessary. The PGT guides the program item by the broadcast organization table, but even the broadcast organization table notified in advance can be changed, so it needs to have a structure that can be updated efficiently. Therefore, the information contained in the PGT is modularized according to type, and the receiver can download only the updated module. Of course, only the updated modules may be collected and downloaded at one time. This is called an integrated delta module.

  For example, when various integrated delta modules with PGT version differences from 1 to N (where N represents the number that falls on one or two days) are provided together, the burden of downloading the receiver becomes noticeable. It can be reduced. If the version of PGT included in SMT is different from the version of PGT currently stored in the receiver, one or more modules in PGT are added / updated / deleted, so the receiver Content downloaded, deleted or deleted modules added or updated should be deleted, and if the PGT version is the same, the receiver needs to download or decrypt the PGT anew There is no

  Each module of the PGT may contain guide information on one or more program items or corresponding packages, or an additional associated table, eg a rating table, required for the decryption of the PGT. )including. The guide information on the package included in the PGT includes the position reference information on the PPT, so that the viewer can select a program using the PGT or can make a scheduled recording. Program content that reduces the amount of information to be included in PGT by guiding the URL (Uniform Resource Locator) of program homepage on the Internet instead of guiding the outline of program content by long text information Outside of the guides, it enables various program guides by HTML pages and services such as "preview" and "replay".

  PPT is information similar to MPEG-2 PMT (Program Map Table), but MPEG-2 PMT is information on the configuration of a program logical channel that does not distinguish program items, and PPT guides program items separately. The PPT can only guide one package corresponding to one program item. The PPT contains information on auxiliary data components as well as all program item components that make up the program item. That is, web documents, widgets, interactive applications, audio clips, video clips, graphics, text, images, as well as information about regular assets such as video and accompanying audio, as well as when needed , Information about auxiliary assets such as auxiliary media components, and location reference information about the resource. Commonly used auxiliary assets in various packages provide information and resources of auxiliary assets in a form that can be shared by various packages.

  Referring to FIG. 3, SMT-S is similar to PPT in terms of structure and function. In the case of Internet broadcasting, there is usually only one program in one IP application data flow, so there is no need to acquire program access information in the two steps SMT and PPT. The same applies to the case where only one program item is broadcasted in one broadcast dedicated physical channel. SMT-S reduces channel acquisition time by combining the functions of SMT and PPT into one. Within the SMT-S, a simple guide for the Internet broadcast channel or the logical channel itself, a location guide for the PGT, a version of the PGT, and a guide for the program items corresponding to the package currently being broadcast, and the package And various pieces of information on the assets 311-1 to 311 -K that make up the Accordingly, the SMT-S integrally transmits logical channel guides, program item guides, program item component information, and the like.

  The PGTs used in Internet broadcasting may include guides for all Internet broadcast channels operated by one Internet broadcaster or broadcaster group, ie all programs included in various IP application data flows. . The viewer may use navigation to select programs from one Internet broadcaster or broadcaster's group using PGT.

  When implementing real-time Internet broadcast by MPEG-DASH, the SMT-S does not have to guide by program item included in the Internet broadcast. For example, this corresponds to live streaming in which the length of a program item (the actual content is a program in which many program items are continuous programs) is not specified. However, in this case, the PGT must be guided by program item.

  The position of PGT provided by SMT-M may be any one of a stream in a physical channel transmitting SMT-M, a stream in another physical channel, a stream in IP application data flow, and an Internet URL. It may be.

  The location of the asset corresponding to each program item component provided by PPT is the stream in the physical channel transmitting the PPT, the stream in the other physical channel, the stream in the IP application data flow, the Internet URL (MPEG-DASH URL And the like). A program item transmitted via a broadcast-only physical channel may be able to view the entire event when the viewer is only relaying a part of the event that the viewer wishes to view for various reasons. It may include information about program items. For example, regular organization can guide an alternative program item by MPEG-DASH, which is a low-resolution video, but allows the viewer to continue to watch it when live broadcast of the HDTV baseball game is interrupted .

  The position of the PGT and the position of the program item component provided by the SMT-S may be a stream in the broadcast-only physical channel carrying the SMT-S or a stream in the IP application data flow, or any other broadcast-only physical channel. Or a stream in a separate IP application data flow, and an Internet URL. If a broadcaster using both a dedicated channel and the Internet implements Internet broadcasting, the location of some program item components of the Internet broadcasting may be streams within a physical channel dedicated for broadcasting.

  When the location of PGT is the Internet URL, the receiver accesses the URL as needed or according to a designated cycle, and updates or adds some modules of the entire PGT or PGT. to download.

  Within one physical channel, only one of SMT-M and SMT-S is included at one time. However, when the number of logical channels in a physical channel changes from many to one, a physical channel containing only SMT-M can contain only SMT-S. In this case, since SMT-M and SMT-S have different values of table_id, the receiver can easily distinguish them.

  One of the main functions of SMT-M and SMT-S is to communicate the latest version information of PGT and the location reference information of PGT. The receiver may download the latest PGT using the latest version information of PGT and the position reference information of PGT included in SMT-M and SMT-S. If the latest version of PGT included in SMT-M and SMT-S is the same version as the PGT already stored in the receiver, the receiver views the content based on the already stored PGT content. Enables the program item to be selected. If the latest version of PGT contained in SMT-M and SMT-S is different from the PGT content already stored in the receiver, the updated PGT will be downloaded and before storage in the receiver is complete, Prevents the viewer from selecting program items based on PGT.

  In an actual system, PGT may not be transmitted, but in such a case, a viewer may select program items mainly based on SMT-M or SMT-S.

  When the receiver is first installed, there is no PGT downloaded, so the automatic channel search searches for the broadcast dedicated physical channel and the logical channel included in it one by one. At this time, when this broadcast system provides PGT, after PGT is downloaded using SMT-M or SMT-S PGT position reference information that has been confirmed for the first time, the viewer can download program items based on PGT. Make it selectable. If this broadcast system does not provide a PGT, the receiver continuously checks all logical channels provided by the broadcast system by performing automatic channel search, and then the viewer channels the channels in the order of logical channels. Allow you to navigate

  When the receiver used subsequently applies power again in the OFF state, the program item of the logical channel that has been viewed before is first reproduced, and in this process, the SMT-M or SMT-S Check PGT information and update PGT. The viewer performs channel navigation in the order of logical channels or decodes PGT information to select a desired program item from program items currently on the air.

  In the case of Internet broadcasting, the broadcast server address already stored at the time of manufacture of the receiver, the broadcast server address input to the receiver by the viewer later, and the broadcast server address acquired by PGT are previously stored in the receiver. It may be stored and selected by the channel navigation of the viewer, or it may be selected based on the program item guide of the PGT.

  When the viewer selects a program item based on the PGT program item guide, the receiver actually accesses the logical channel to which the program item is transmitted, and is currently being broadcast via that logical channel. Show the program item of. Although very rare, from the time the viewer selects a program item with reference to the program item guide of PGT, the time immediately before the actual SMT-M or SMT-S of the program item concerned is decoded, The content of PGT may be updated. In such a case, the receiver updates the PGT using PGT information included in SMT-M or SMT-S, and the program item currently being viewed by the viewer due to emergency organization is the previous version of If different from the PGT-guided program item, an appropriate guide is displayed on the screen to allow the viewer to recognize the currently watched program item.

  Referring to FIG. 3, the asset referenced by the SMT-S or PPT may actually be a media asset or another PPT. However, a PPT referenced by SMT-S or PPT does not allow a double circular reference that references again another PPT. If the SMT-S or PPT also refers to another PPT as an asset, it is necessary to transmit MMT composition information for screen layout. If the screen layout does not change according to time within one program item and it is fixed, if this amount is not large, MMT (MPEG Media Transport) composition information is included in the descriptor in PPT and transmitted. May be When the screen layout changes according to time in one program item, the MMT composition information is transmitted as a timed asset. On the other hand, the MMT composition information may be transmitted as an untimed asset when there is a large amount of composition information although the screen layout does not change according to time within one program item.

  The SSI proposed in the present invention can also be used interchangeably in a broadcast system based on the existing MPEG-2 system standard.

  FIG. 4 is a diagram showing an example of use of SSI in MPEG-2 TS based broadcasting according to an embodiment of the present invention. For example, FIG. 4 shows an example of an MPEG-2 TS that can be interpreted by both an existing broadcast receiver and a receiver that supports MMT.

  Referring to FIG. 4, in this example, two programs exist in one TS. An existing broadcast receiver decrypts MPEG-2 PAT, MPEG-2 PMT1, and MPEG-2 PMT2 and receives a program. A receiver supporting MMT decrypts the MMT SMT-M, the MMT PPT1, and the MMT PPT2 to receive the program. Of course, the PID of the TS packet carrying the MMT SMT-M needs to be pre-assigned as a fixed value, and the SMT-M and PPT are transmitted after being encapsulated in the structure of the MPEG-2 section There is a need.

  Next, the SSI information format standard proposed by the embodiment of the present invention will be described. SMT-M (Service Map Table for Multiple packages), when broadcasting a plurality of logical channels via a dedicated broadcast physical channel, is a dedicated physical channel of the relevant broadcast, corresponding to all program items currently being broadcast. It is used to communicate the position and the version and position of the program guide. The SMT-M is preferably transmitted in a cycle of 500 ms, so that when the receiver accesses the dedicated physical channel of the broadcast, it quickly finds the package corresponding to the program item.

  The APID of SMT-M is always fixed at a specific value (for example, 0x0000). In the case of transmitting SMT-M via MPEG-2 TS, it is necessary to specify the PID of the TS packet carrying SMT-M as a fixed value.

  The syntax (syntax) of SMT-M is as shown in Table 1. The definition of the content listed in the "Form" column of Table 1 conforms to the MPEG-2 system standard. Moreover, the loop count (loop count) not displayed in the “value” column of Table 1 is a value derived from the value indicating the length. Such principles also apply to the other tables presented by the embodiments of the present invention.

In Table 1, the semantics of each syntax element are as follows.
table_id: An identifier indicating the type of table. A unique value corresponding to SMT-M is assigned.
version_id: An identifier indicating the configuration of this table. This value also changes when the table configuration is modified by standard revision. The receiver determines, based on this value, whether this table is configured to be able to understand the contents of the table by itself. This value is increased only when the contents of the table are revised incompatiblely with the existing one.

table_length: The number of bytes from the next to this field to the last byte of service_map_table_type_I (). A value of 0 is not used.
service_id: A unique identifier for a broadcast service using a dedicated broadcast channel. A unique identifier needs to be assigned to each broadcaster's dedicated broadcast channel via the registration organization.

  SMT_update_version: Since SMT-M is transmitted periodically, if the content of SMT-M is different from the content of SMT-M having the same service_id transmitted immediately before, this value is incremented by one. After the maximum value 255, it is reset to 0. The receiver reads and decrypts the SMT-M content again if this value changes.

  SMT_prefix_count: Number of subsequent SMT_prefixes. SMT_prefix is concatenated before the text string included in SMT-M to form a URL. When referring to SMT_prefix, SMT_prefix is referred to using the appearance order of SMT_prefix as an index. The value "OxFF" in this field is not used. Therefore, up to 255 SMT_prefixes may be included.

SMT_prefix_length: Length of SMT_prefix text string.
SMT_prefix_byte: byte of SMT_prefix text string. The last null byte of the text string is not included.

  SMT_M_descriptors_length: Represents the length of the SMT_M_descripor syntax loop immediately following this field as the number of bytes from the next byte to the last byte of the SMT_M_descripor syntax loop. SMT_M_descripor () may include various descriptors, including PGT_reference_descriptor () described below.

number_of_packages: The number of packages currently being communicated over this broadcast channel.
package_path_number: Package path number that distinguishes a logical channel in a certain broadcast channel. The value of "0" is not used. package_path_number is uniquely assigned within a physical channel by one broadcaster or broadcaster group.

  package_id: The identifier of the package currently being communicated via this virtual channel. package_id is a value assigned by the broadcaster for each package, and has a unique value of a package provided by one broadcaster or broadcaster group during a certain period. This value may be reused after a certain period of time.

  simple_location_type: Specifies the type of location reference information for the PPT corresponding to the package currently being transmitted. The PPT to which SMT-M refers is conveyed in the same IP application data flow as the IP application data flow carrying SMT-M or in the same MPEG-2 TS as the MPEG-2 TS carrying SMT-M Be done. If the value of this field is “0”, the asset path carrying PPT is specified as APID, and if the value of this field is “1”, MPEG-2 TS carrying PPT is defined in MPEG-2 Designate as the specified PID.

PPT_APID: Identifier of an asset path carrying PPT in IP application data flow.
PPT_PID: PID of TS packet carrying PPT in MPEG-2 TS.
CRC_32: A field identical to CRC_32 as defined in the section syntax of the MPEG-2 system standard.

  SMT-S (Service Map Table for a Single package) is a program item for broadcasting one logical channel via a dedicated broadcast physical channel, or using only the Internet, or using it for broadcasting. It is used to convey simple guide information for the corresponding package, location reference information for more detailed program guide information, program item configuration, and location reference information for its components. The SMT-S needs to be transmitted in a cycle of 500 ms, and the APID of the SMT-S is always fixed as a specific value (for example, 0x0000). Therefore, SMT-M and SMT-S are transmitted via a path having the same APID, but are identified by table_id.

The syntax of SMT-S is as shown in Table 2.

In Table 2, the meaning of each syntax element is as follows.
table_id: An identifier indicating the type of table. A unique value corresponding to SMT-S is assigned.

  version_id: An identifier indicating the configuration of this table. This value also changes when the table configuration is modified by standard revision. The receiver determines, based on this value, whether this table is configured to be able to understand the contents of the table by itself. This value is increased only when the table content is revised incompatiblely with the existing one.

table_length: The number of bytes from the next to this field to the last byte of service_map_table_type_II (). A value of 0 is not used.
service_id: A unique identifier for the Internet broadcast service. It is necessary to assign a unique identifier for each IP application data flow of each broadcaster via the registration authority.

  SMT_update_version: Since SMT-S is periodically transmitted, this value is incremented by one if the content of SMT-S is different from the content of SMT-S having the same service_id transmitted immediately before. After the maximum value 255, it is reset to 0. The receiver reads and decrypts the SMT-S content again if this value changes.

CRC_32 is the same field as CRC_32 defined in the section syntax of the MPEG-2 system standard.
PPT_body (): A syntax element group corresponding to the body of PPT in MMT, whose syntax is as shown in Table 3.

In Table 3, the meaning of each syntax element is as follows.
short_channel_name_length: The number of bytes of the logical channel name represented by the text string using UTF-8 encoding.

short_channel_name_byte: Byte data constituting the logical channel name.
package_id: The identifier of the package currently being communicated via this virtual channel. package_id is a value assigned by the broadcaster for each package, and has a unique value of a package provided by one broadcaster or broadcaster group during a fixed period. This value may be reused after a certain period of time.

  prefix_count: Number of subsequent prefixes (prefix). The prefix is concatenated to the end of the text string to form a URL. When trying to refer to a prefix, the receiver refers to the prefix by using the order of appearance of the prefix as an index. The value "OxFF" in this field is not used. Thus, up to 255 prefixes can be included.

prefix_length: Length of prefix text string.
prefix_byte: byte in prefix text string. The last null byte of the text string is not included.

  descriptors_length: The length of the descriptor syntax loop immediately following this field is expressed as the number of bytes from this next byte to the last byte of the descriptor syntax loop. Although various descriptors may be included in the descriptor (), if the PPT_body () syntax element group in Table 3 is included in the SMT-S, PGT_reference_descriptor () is included in this descriptor (). It may be

  parental_guidance_flag: If the value of this flag is '1', the receiver will not play the content restored from the package before deciphering the PGT to verify the correct audience rank applied to this package . If the value of this flag is “0”, the receiver reproduces the content restored from the package even before confirming the viewer rank.

recording_flag: If the value of this flag is “1”, the receiver can store this package on a storage medium in the receiver.
random_access_flag: If the value of this flag is “1”, the viewer can make arbitrary access to this package.

fast_forward_play_flag: If the value of this flag is "1", the viewer can perform fast play with this package.
fast_reverse_play_flag: If the value of this flag is “1”, the viewer can perform fast reverse playback with this package.

timescale_flag: When the value of this field is “1”, the timescale field is included below.
protection_scheme_id_flag: If the value of this field is “1”, the protection_scheme_id field is included below.

  timescale: Represents the time unit applied to the various timestamps of an asset as a number of time units per second. The default value is 90,000. The timescale field is in two places in PPT_body (), but the predecessor is the value applied to the entire asset belonging to the package, and the latter in the asset syntax loop is the value applied to each asset It is. If there is a value applied to each asset, this value takes precedence over the value applied to the entire preceding asset.

  protection_scheme_id: A value specifying the asset encryption method. Although the protection_scheme_id field is in two places in PPT_body (), the preceding one is the value applied to the entire asset belonging to the package, and the latter in the asset syntax loop is applied to each asset It is a value. If there is a value applied to each asset, this value takes precedence over the value applied to the entire preceding asset.

  clock_reference_id: A clock identifier used by the asset's encoder. The clock_referece_id field is in two places in PPT_body (), but the predecessor is the value applied to the entire asset belonging to the package, and the latter in the asset syntax loop is the value applied to each asset It is. If there is a value applied to each asset, this value takes precedence over the value applied to the entire preceding asset.

  number_of_asset_groups: Number of asset groups. Assets belonging to the same asset group are mutually exclusive. That is, the receiver reproduces only one of the assets belonging to the same group. For example, for multilingual support, audio of A language and audio of B language may belong to the same asset group.

  level_of_mandatory_playing: A value indicating whether or not one asset in the asset group needs to be played. If the value of this field is "0", the receiver is required to reproduce one asset of this asset group. If the value of this field is not "0", the receiver does not have to play the assets belonging to the asset group by its ability. However, the larger the value of this field, the lower the importance. The receiver may omit asset groups with small values in this field, and there is no need to play asset groups whose field values have larger values.

number_of_assets_in_group: The number of assets that belong to this asset group.
asset_type: Asset type. This is a field similar to stream_type in MPEG-2 PMT, but an extension of this. If asset_type is PPT, this asset is referred to as a PPT asset. However, double cyclic reference in PPT assets included in SMT-S or PPT and referring to other PPT assets is not allowed.

asset_id: Asset identifier. asset_id is used to point to an asset in MMT_package_composition_descriptor ().
default_selection_flag: When the value of this flag is “1”, it indicates that the asset is an asset that has been preferentially recommended in the asset group to which it belongs. It is necessary to set the value of this flag to "1" only for one asset among assets belonging to the same asset group. If the value of this flag is “0” for all assets belonging to the same asset group, the receiver regards the earliest appearing asset as the preferentially recommended asset.

clock_reference_flag: When the value of this flag is “1”, it indicates that the clock_reference_id field is included in the following syntax.
asset_timescale_flag: When the value of this flag is “1”, it indicates that the timescale field is included in the following syntax.
asset_protected_flag: When the value of this flag is “1”, it indicates that the asset is encrypted.

scheme_id_flag: When the value of this flag is “1”, it indicates that the protection_scheme_id field is included in the following syntax.
MMT_general_location_info (): General location reference information for MMT, which specifies the location of the asset. The contents are as shown in Table 5.
asset_descriptors_length: The number of bytes following this field to the last byte of the descriptor syntax loop.
asset_descriptor (): Asset descriptor.

  PPT_asset () is a syntax element group used to include other packages in a certain package. The syntax is as shown in Table 4, and the meaning of each syntax element is as defined in Table 3 above.

  MMT_general_location_info () is a syntax element group that provides asset location reference information in MMT. The syntax is as shown in Table 5.

In Table 5, the meaning of each syntax element is as follows.
location_type: As shown in Table 6, specify the format of location reference information.

AMID: Identifier of the module in the asset path.
APID: Identifier of asset path in IP application data flow.
Ipv4_src_addr: IP version 4 source address of IP application data flow (source address).
ipv4_dst_addr: IP version 4 destination address of IP application data flow (destination address).
dst_port: Destination port number of IP application data flow.
ipv6_src_addr: IP version 6 source address of IP application data flow.
ipv6_dst_addr: IP version 6 destination address of IP application data flow.
network_id: broadcast network identifier for transmitting an MPEG-2 TS.
MPEG_2_transport_stream_id: identifier of MPEG-2 TS.
MPEG_2_PID: PID of an MPEG-2 TS packet.

prefix_index: An index specifying one of the prefixes stored in the receiver before decrypting this field. If the value of this field is OxFF, it indicates that there is no prefix.
URL_length: Length of URL. The last null byte (0x00) of the text string is not included.
URL_byte: byte of URL. The final null byte of the text string is not included.
byte_offset: The byte offset from the beginning of the file.
length: Length in bytes.

  PPT (Package Packing Table) is a program item and a brief guide information on a package corresponding to the program item, a position reference information on program guide information in more detail, and a program item in the case of a broadcast using a physical channel dedicated to broadcast. And the position reference information of the component. The PPT is preferably transmitted in a cycle within 500 ms.

  The syntax of PPT is almost the same as the syntax of SMT-S except that the service_id syntax element is replaced with the package_path_number syntax element in the syntax of SMT-S. The syntax of PPT is as shown in Table 7. Most syntax elements are similar to SMT-S in terms of meaning, so we define only syntax elements that have different meanings.

In Table 7, the meaning of each syntax element is as follows.
table_id: An identifier indicating the type of table. Assign appropriate values to PPT.
package_path_number: A number of package path that distinguishes a logical channel in a certain broadcast channel. The value of "0" is not used. package_path_number is uniquely assigned within a physical channel by one broadcaster or broadcaster group.

  The PGT (Package Guide Table) can guide a program organized into all broadcasts operated by one broadcaster or one broadcaster group as program guide information. The PGT is preferably transmitted in a cycle of less than one minute.

  The PGT basically provides guide information in units of program items. The receiver classifies and provides this by physical channel or logical channel. Of course, PGT contains information that enables such sorting. Guide information of program items may be arranged and transmitted according to a predetermined rule on the transmitting side.

  The program item is identified by the package identifier, package_id, which is its encoding form. The package_id can uniquely identify a broadcaster or a program item provided by a broadcaster group. One broadcaster or one broadcaster group is uniquely identified by PGT_provider_id. PGT_provider_id needs to designate a registration organization and allocate it according to the request of each broadcaster or broadcaster group. In the case of package_id, each broadcaster or broadcaster group inherently assigns it uniquely to its own program item. Since package_id is a 16-bit value and can identify a finite number of program items, it needs to be reused after a certain period of time. At the time of reuse, package_id_recycle_number (which is 8 bits as one of syntax elements included in PGT_package_info ()) is incremented by one. A set of three pieces of information consisting of PGT_provider_id, package_id_recycle_number, and package_id becomes a globally unique identifier for a program item or a package corresponding thereto until the package_id_recycle_number is exhausted. For example, assuming that it takes approximately one year until the package_id is exhausted, since package_id_recycle_number is 8 bits, uniqueness is guaranteed for about 256 years.

  PGT consists of an identifier of a broadcasting company or broadcaster group providing PGT, an updated version, a homepage URL of a broadcasting company or broadcaster group providing PGT, updated module information, logical channel information, package information, attached table information, etc. Be done. The update module information is information including only a portion different from the past PGT version distinguishable from the current PGT version as a form of delta information. If PGT includes update module information corresponding to one or two days, PGT update process in the receiver can be performed very efficiently.

The syntax of PGT is as shown in Table 8.

In Table 8, the meaning of each syntax element is as follows.
table_id: An identifier indicating the type of table. Assign appropriate values to PGT.
version_id: An identifier indicating the configuration of this table. This value also changes when the table configuration is modified by standard revision. The receiver determines, based on this value, whether this table is configured to be able to understand the contents of the table by itself. This value is increased only when the contents of the table are revised incompatiblely with the existing one.

  PGT_provider_id: A unique identifier of an institution providing a PGT. One organization can provide one PGT, and PGT_provider_id is assigned by a suitable registration authority.

  PGT_update_version: Version number indicating whether PGT content has been changed. This value is incremented by one when the content of PGT is updated. After the maximum value 255, it is reset to 0. If the PGT version number stored by the receiver is different from this value, the receiver rereads the PGT and decrypts its contents.

table_length: The number of bytes from the next of this field to the last byte of package_guide_table (). A value of 0 is not used.
PGT_prefix_count: Number of prefixes used in PGT. The prefix is concatenated to the end of the text string contained in PGT. When referring to a prefix, the prefix is referred to by using the order of appearance of the prefix as an index. The value of OxFF is not used as an index value. Thus, up to 255 prefixes may be included.

PGT_prefix_length: Length of text string of PGT_prefix.
PGT_prefix_byte: byte of text string of PGT_prefix. The final null byte of the text string is not included.
PGT_provider_homepage_URL_prefix_index: Index to the prefix of the homepage URL of the institution providing the PGT. A value that designates one of the preceding prefixes, and the value of this field is OxFF, indicates that there is no prefix text string.

PGT_provider_homepage_URL_length: The length of the postfix bytes in the homepage URL of the institution providing the PGT.
PGT_provider_homepage_URL_byte: ASCII text value of postfix in the homepage URL of the provider providing the PGT.
PGT_descriptors_length: The length of the next descriptor syntax loop byte.
PGT_descriptor (): A descriptor of association with PGT.

  redirect_flag_for_delta_update_info: If the value of this flag is "0", the PGT update information is directly included in the PGT, and if the value of this flag is "1", it is located elsewhere.

  redirect_flag_for_logical_channel_info: When the value of this flag is “0”, the logical channel information is directly included in PGT, and when the value of this flag is “1”, it is located elsewhere.

  redirect_flag_for_package_info: If the value of this flag is “0”, package information is directly included in the PGT, and if the value of this flag is “1”, it is located elsewhere.

  redirect_flag_for_associated_table_info: If the value of this flag is “0”, the adjunct table information is directly included in the PGT, and if the value of this flag is “1”, it is located elsewhere.

PGT_delta_update_info_module_count: The number of PGT_delta_update_info_module.
PGT_update_delta: A value corresponding to the difference between the past PGT version used as a reference and the current PGT version when creating a PGT_delta_update_module. The next MMT_general_location_info () specifies the location of PGT_delta_update_module ().
PGT_delta_update_info_module (): A data module consisting of only different information between a previous version PGT, such as PGT_update_delta, and the current version PGT.

  PGT_logical_channel_info_update_version: The version of PGT_logical_channel_info () defined in Table 10. Immediately after MMT_general_location_info () specifies the location of PGT_logical_channel_info ().

PGT_logical_channel_info (): logical channel information defined in Table 10.
PGT_package_info_module_count: Number of PGT_package_info_module ().
PGT_package_info_module_id: identifier of PGT_package_info_module ().
PGT_package_info_module_update_version: version of PGT_package_info_module (). Immediately after MMT_general_location_info () specifies the location of PGT_package_info_module ().

PGT_package_count: Number of packages.
PGT_package_info (): Package information defined in Table 11. One package information contains only one package information.

PGT_associated_table_info_module_count: The number of PGT_associated_table_info_module ().
PGT_associated_table_info_module_id: identifier of PGT_associated_table_info_module ().

  PGT_associated_table_info_module_update_version: version of PGT_associated_table_info_module (). Immediately after MMT_general_location_info () specifies the location of PGT_associated_table_info_module ().

PGT_associated_table_count: Number of PGT attached tables. Tables having the same table_id are regarded as one table.
PGT_associated_sub_table_count: Number of sub-tables (sub-tables) in the table attached to PGT.

PGT_associated_sub_table (): Subtable in PGT attached table.
PGT_delta_update_info_module () is a syntax element group including only updated information in PGT content. The PGT_delta_update_info_module () may optionally include updated logical channel information, updated package information, and updated associated sub-tables.

  If PGT_update_version is different from the PGT version stored by itself, the PGT_update_delta is the difference between PGT_descriptor () loop deciphering the PGT contents and then subtracting the PGT version stored by itself from PGT_update_version. If PGT_update_delta is present, PGT update can be completed by decrypting the PGT_delta_update_info_module ().

The syntax of PGT_delta_update_info_module () is as shown in Table 9.

In Table 9, the meaning of each syntax element is as follows.
PGT_update_delta: A value corresponding to a difference between a past PGT version as a reference and a current PGT version when creating a PGT_delta_update_module.
PGT_delta_update_info_module_length: The number of bytes from the next of this field to the last byte of PGT_delta_update_info_module ().

update_logical_channel_info_flag: When the value of this flag is “1”, it indicates that update information on logical channel information is included.
update_package_info_flag: If the value of this flag is “1”, it indicates that the update information on the package information is included.
update_associated_table_flag: When the value of this flag is “1”, it indicates that update information on table information attached to the PGT is included.

PGT_logical_channel_info (): Logical channel information defined in Table 10.
PGT_package_update_count: Number of package update information included in the next syntax loop.
PGT_package_info (): Package information defined in Table 11.
PGT_associated_table_update_count: The number of sub-tables (sub-tables) in the updated PGT attached table included in the next syntax loop.
PGT_associated_sub_table (): Subtable in PGT attached table.

  PGT_logical_channel_info () is a syntax element group corresponding to metadata of all logical channels provided by the PGT provider among contents of the PGT.

  The syntax of PGT_logical_channel_info () is as shown in Table 10. Here, PGT_logical_channel_index which is a syntactic loop index is an index used in package information.

In Table 10, the meaning of each syntax element is as follows.
PGT_logical_channel_info_update_version: version of PGT_logical_channel_info (). It is incremented by one each time the content of the logical channel information changes, and is reset to 0 at 255.

PGT_logical_channel_info_length: The number of bytes from the next of this field to the last byte of PGT_logical_channel_info ().
PGT_logical_channel_count: Number of logical channels guided by PGT.
short_channel_name_length: The number of bytes of the logical channel name represented by the text string using UTF-8 encoding.

short_channel_name_byte: Byte data constituting the logical channel name.
physical_channel_type: The type of physical channel that carries the relevant logical channel. If the value of this field is "0", it indicates the Internet, if it is "1", it indicates terrestrial waves, if it is "2", it indicates satellites, and if it is "3", it indicates cables.

major_channel_number: Main channel number.
minor_channel_number: Secondary channel number.
service_id: MMT service identifier.

  package_path_number: Package path number that distinguishes a logical channel in a certain broadcast channel. The value of "0" is not used. package_path_number is uniquely assigned within a physical channel by one broadcaster or broadcaster group.

  test_channel_flag: Indicates that this logical channel is a test logical channel. When the value of this flag is "1", the general receiver does not provide this logical channel information in the program guide.

nvod_channel_flag: Indicates that this logical channel is for NVOD (Near Video On Demand).
relay_broadcast_flag: Indicates that this logical channel is a retransmission channel of another logical channel. For example, when retransmitting terrestrial broadcasting by cable, the value of this flag is set to "1" for the logical channel.

  channel_protection_type: Indicates the encryption type applied to this logical channel. If the value of this field is "0", that it is not encrypted, if it is "1", that all packages in this logical channel are encrypted, it is "2", If only a part of the assets belonging to the package in this logical channel or a part of the whole / a part of the asset is encrypted, if "3", then only a part of the package is encrypted. Show. If the value of this field is "2", for example, it indicates that only the video is encrypted or only for the first 10 minutes of the package. If the value of this field is "3", for example, it indicates that only a few packages conveyed by this logical channel are encrypted.

original_physical_channel_type: Original physical channel type.
original_major_channel_number: Original primary channel number.
original_minor_channel_number: Original secondary channel number.
MMT_general_location_info (): Designates the location of PPT or SMT-S corresponding to this logical channel.
descriptors_length: Length of next descriptor syntax loop.
descriptor (): Logical channel information and association descriptor.

  PGT_package_info () is a syntax element group corresponding to metadata of one package among contents of PGT. The syntax of PGT_package_info () is as shown in Table 11.

In Table 11, the meaning of each syntax element is as follows.
package_id: The identifier of the package currently being communicated via this logical channel. package_id is a value assigned by the broadcaster for each package, and has a unique value of the package for a certain period. This value may be reused after a certain period of time.
PGT_package_info_update_version: version of PGT_package_info (). This value is incremented by one each time the content of the package information changes, and is reset to 0 at 255.

PGT_package_info_length: The number of bytes from the next of this field to the last byte of PGT_package_info ().
package_id_recycle_number: The value of this field is incremented by one each time the assignment of the 16-bit package_id number is completed. It becomes a unique package identifier with package_id.

start_time: Indicates the start time of a program item corresponding to this package in UTC.
duration: Indicates the duration of the program item corresponding to this package in seconds. If the value of this field is "0", it means "do not know the duration time".

title_text_language_count: The number of languages indicating the title of the program item applicable to this package.
title_text_language: A 3-byte language identifier according to the ISO 639 standard, which indicates the title language of the program item corresponding to this package.
title_text_length: The length of the UTF-8 text string indicating the title of the program item corresponding to this package is notified in units of bytes.
title_text_byte: The text string byte of the title of the program item applicable to this package.

  package_homepage_URL_prefix_index: Index of prefix for homepage URL of program item corresponding to this package. This field has a value specifying one of the prefixes defined in PGT_header (). If the value of this field is OxFF, it indicates that there is no prefix.

package_homepage_URL_length: The length of the next postfix in the homepage URL of the program item applicable to this package.
package_homepage_URL_byte: ASCII text value of postfix in the homepage URL of the program item applicable to this package.

  format_type: Specifies the format of PGT_package_info (). If the value of this field is "0", then PGT_package_info () contains the minimum information for the current or future package, and if it is "1", then PGT_package_info () indicates the already broadcasted program item. If only "Replay" information is included and "2", PGT_package_info () includes all information about the program broadcast now or afterward. "Replay" is a service that allows program items that have already been broadcasted to be downloaded or streamed free of charge from the Internet server and viewed.

PGT_logical_channel_index: Index specifying information on the logical channel carrying this package. The value of this index is the index of the logical channel provided by PGT_logical_channel_info () in Table 10.
post_event_replay_URL_flag: Indicates that a "replay" URL for this package exists.

  post_event_replay_URL_prefix_index: Index to the prefix of "Replay" URLs for this package. This field has a value specifying one of the prefixes defined in PGT_header (). When the value of this field is "0", it indicates that there is no prefix. If the value of this field is not "0" but "N", specify the Nth prefix.

post_event_replay_URL_length: The length of the next postfix in the "replay" URL of this package.
post_event_replay_URL_byte: ASCII text value of the postfix of the "Replay" URL of this package.

  package_protection_type: Indicates the encryption type applied to this package. If this value is "0", that it is not encrypted, if it is "1" that all assets in this package are encrypted, if it is "2", it is in this package Indicates that only part of an asset or part of an asset is encrypted, and the value of "3" is not used. If the value of this field is "2", for example, it indicates that only video assets are encrypted or only the first 10 minutes of video and audio assets are encrypted.

  pay_type: This field has no meaning when the package_protection_type is "0", so it is ignored by the receiver, and has a meaning in the case of "1" or "2". If the value of this field is “0”, it indicates “pay-per-view” if it is “pay subscription required” and if it is “1”. Relevant payment guide information needs to be provided using a descriptor within the PGT_descriptor () syntax loop of Table 8 or the PGT_package_info_descriptor () syntax loop of Table 11. If payment guide information is present in both the PGT_descriptor () syntax loop and the PGT_package_info_descriptor () syntax loop, the one in the PGT_package_info_descriptor () syntax loop takes precedence.

  content_id_flag: If the value of this flag is “1”, it indicates that a globally unique content identifier is included for the program item corresponding to this package.

  genre_flag: If the value of this flag is “1”, it indicates that the genre information of the program item corresponding to this package is included. If the value of this flag is "1", it is necessary to transmit the genre table (genre table) to the receiver as PGT_associated_table.

  parental_guidance_flag: When the value of this flag is “1”, it indicates that the viewer rank information is included. If the value of this flag is "1", the viewer rank table needs to be transmitted to the receiver as PGT_associated_table.

live_flag: If the value of this flag is “1”, this indicates that this package is live broadcast rather than recorded video or recorded content.
serial_flag: When the value of this flag is “1”, it indicates that the program item corresponding to this package is one of the series like a drama series.
rebroadcast_flag: If the value of this flag is "1", it indicates that the program item corresponding to this package is "re-broadcast" of a program item that has already been broadcasted.

rebroadcast_exist_flag: If the value of this flag is “1”, it indicates that there is a “rebroadcast” plan for the program item corresponding to this package.
recording_flag: When the value of this flag is “1”, it indicates that this package can be recorded.
multilingual_flag: If the value of this flag is "1", it indicates that multi-lingual audio is supported.

commentary_channel_flag: If the value of this flag is "1", it indicates that there is a "screen commentary broadcast" for this package.
sign_language_flag: If the value of this flag is "1", it indicates that there is a "sign language broadcast" for this package.
subtitles_flag: If the value of this flag is "1", it indicates that there is "subtitle broadcast" for this package. Subtitles are in UTF-8 encoding.

  multivew_flag: If the value of this flag is “1”, this indicates that the entire package is “multi-view broadcast” or that “multi-view broadcast” is partially included in this package. "Multi-view broadcasting" includes binocular stereoscopic broadcasts, multi-view 3D broadcasts, multi-view broadcasts, and the like.

  picture_size_grade_count: The number of screen size ranks. If the value of this field is "2" or more, it indicates that multiple screen size ranks are provided by simultaneous broadcast or spatial scalability encoding.

  picture_size_grade: Screen size rank. For example, if the value of this field is “0”, the horizontal resolution is 240 pixels, “1”, 480 pixels, “2”, 720 pixels, “3”. If there are 1,280 pixel class, "4", 1,920 pixel class, "5", 3,840 pixel class, "6", 7,680 pixel class. A picture_size_grade of 2 or more indicates that the video is provided by spatial scalability encoding.

audio_language: A 3-byte language identifier according to the ISO 639 standard indicating the language of audio.
audio_grade: Indicates the type of audio. For example, if the value of this field is "0", it indicates that the audio is mono, if "1" indicates that the audio is stereo, and if "2", the audio is 5. Indicate “1 channel audio”, and “3” indicates audio is 22.2 channel audio.

additional_audio_count: The number of additional other language audio.
additional_audio_language: 3-byte ISO 639 language identifier for additional audio in a language different from the main audio.
additional_audio_grade: Indicates the type of additional other language audio. For example, if the value of this field is "0", it indicates that the audio is mono, if "1" indicates that the audio is stereo, and if "2", the audio is 5. Indicate “1 channel audio”, and “3” indicates audio is 22.2 channel audio.

content_originator_id: A globally unique identifier indicating the author of the main content of the program item that corresponds to this package. This identifier should be used after registering with a suitable registrar.
content_id: content identifier for the program item corresponding to this package. This identifier is managed by each author. A set of content_originator_id and content_id is a world-unique content identifier.

content_major_version: The major version of the program item that corresponds to this package.
content_minor_version: Index of minor version of program item that corresponds to this package.
genre_system_id: Identifier of the system that classifies the genre. Actually, it corresponds to sub_table_id of the genre table.

major_genre: Index of the main genre of the program item that corresponds to this package. This index is an index to the main genre entry in the genre table. For example, the main genre may be sports.
minor_genre: The minor genre index of the program item that corresponds to this package. This index is an index to the entry of the minor genre in major_genre in the genre table. For example, the sub-genre may be soccer among sports.

rating_system_id: identifier of a system for classifying a viewer rank. Actually, it corresponds to sub_table_id of the viewer rank table.
rate_index: Index indicating the viewer rank of the program item corresponding to this package. This index is an index for the viewer rank entry in the viewer rank table.

season_number: Season number of the series. When the value of this field is "0", it indicates that there is no season of the series.
serial_number_minus1: Indicates one less than the number of times in series season.
prequel_package_id: package_id of the first package of the program item corresponding to this package. When the value of this field is "0", it indicates that the program item corresponding to this package is the first of the series.

sequel_package_id: package_id of the next package of the program item corresponding to this package. If this field value is "0", it indicates that the program item corresponding to this package is the last round of the corresponding season of the series.
rebroadcast_package_id: The identifier of the package that corresponds to "rebroadcast" for this package.

commentary_channel_count: The number of languages for "screen commentary broadcast" about this package.
commentary_language: A 3-byte language identifier according to the ISO639 standard that specifies the language of "screen commentary broadcasting".
subtitle_count: The number of "subtitled broadcast" languages for this package.
subtitle_language: A 3-byte language identifier according to the ISO639 standard that specifies the language of "subtitle broadcast".

karaoke_flag: When the value of this flag is “1”, it indicates that the subtitle is a karaoke style.
multiview_coverage_type: A value of “0” in this field indicates that the whole package is multiview video, and “1” indicates that only a part of this package is multiview video.

  multiview_scheme_type: If the value of this field is “1”, it indicates that the “multi-view broadcast” system is binocular stereoscopic, and if it is “2”, the “multi-view broadcast” system has many When it is "3", it shows that it is viewpoint 3D, the system of "multi-view broadcasting" shows that it is an inward-type multi-view, and when it is "4," the system of "multi-view broadcasting" is In the case of “5”, it indicates that the “multi-view broadcast” system is a multi-view in various directions.

PGT_package_info_descriptors_length: Length of next PGT_package_info_descriptor () syntax loop.
PGT_package_info_descriptor (): An area where additional descriptors can be inserted.

  The syntax of PGT_associated_sub_table () follows the general MMT table syntax, as shown in Table 12. The meaning of each syntax element is defined below.

table_id: An identifier indicating the type of this table.
version_id: An identifier indicating the configuration of this table. As the standard revision modifies the configuration of this table, the value of this field also changes. The receiver determines, based on this value, whether this table has been configured to be able to understand the contents of the table itself. This value is increased only when the contents of the table have been revised incompatiblely with existing ones.

table_sub_id: Identifier of the subtable.
update_version: A version number that indicates the change in content from the next to this field to the last byte of this subtable. This value is incremented by one if the content of this table is updated. This value is reset to 0 after the maximum value 255. If the version number of the subtable stored therein is different from the value, the receiver rereads and decodes this subtable.

table_length: The number of bytes from the next to this field to the last byte of this sub-table.
sub_table_contents (): Content changed by each sub table.
CRC_32: A field identical to CRC_32 defined in the section syntax of the MPEG-2 system standard.

  PGT_package_info_module () is a guide for one or more packages when the PGT includes package guide information indirectly by referring to an external route or file in which the package guide information is not contained and directly refers to the package guide information. It is a data structure that contains.

The syntax of PGT_package_info_module () is as shown in Table 13, and the meaning of each syntax element is defined below.

PGT_package_info_module_id: identifier of PGT_package_info_module (). This identifier is reusable, and this module always contains information about the same package unless this identifier is reused.
PGT_package_info_module_update_version: An updated version of PGT_package_info ().
Whenever the content of the next field changes, this field is incremented by one regardless of the reuse of the identifier, and is reset to 0 at the maximum value 255.
PGT_package_info_module_length: The number of bytes from the next of this field to the last byte of PGT_package_info ().
reallocation_flag: When the value of this field is “1”, this module contains information on a package different from the package included in the previously received module, which has the same identifier as the identifier of this module Indicates that. That is, it indicates that the identifier is to be reused.
PGT_package_count_in_this_module: The number of package information included in this module.
CRC_32: A field identical to CRC_32 defined in the section syntax of the MPEG-2 system standard.

  AAT (Adjunct Asset Table) transmits information on auxiliary assets (adjunct asset). The AAT is periodically transmitted as a separate asset constituting a package to which a primary asset (primary asset) corresponding to an auxiliary asset included in the AAT belongs.

  The method of synchronizing the main asset with the supplementary asset and the definition of AAT are described in Korean Patent Application No. 2011-0095458. In the present specification, the syntax of AAT and the meaning of each field are shown below for convenience of explanation.

The syntax of AAT is as shown in Table 14, and the meaning of each field is defined below.

table_id: An identifier indicating the type of table. Assign appropriate values to AAT.
version_id: An identifier indicating the configuration of AAT. The value of this field also changes when the table configuration is modified by standard revision. The receiver refers to this value to determine whether this table is configured to be understood by itself.
sub_table_id: When the entire table is divided into a large number of subtables and transmitted, each subtable is identified.

update_version: Since the AAT is transmitted periodically, this value is incremented by one if the content of the AAT is different from the content of the AAT having the same sub_table_id transmitted immediately before. After the maximum value 255, it is reset to 0. When this value changes, the receiver rereads and decrypts the AAT's content.
table_length: The number of bytes from the next to this field to the last byte of AAT. A value of 0 is not used.

  locator_prefix_count: Number of next locator_prefix. locator_prefix is concatenated with the locator text string provided by adjunct_asset_locator to form a URL. adjunct_asset_locator refers to locator_prefix using the order of appearance of locator_prefix as an index. The value OxFF in this field is not used. Thus, up to 255 locator_prefixes can be included.

locator_prefix_length: Length of locator_prefix text string.
locator_prefix_byte: byte of locator_prefix text string. The final null byte of the text string is not included.
adjunct_asset_type: Auxiliary asset type. Assign unique values to each type, for example, web documents, widgets, interactive applications, audio clips, video clips, graphics, text, images, supplemental media components, etc. This adjuct_asset_type value applies to auxiliary assets in the next syntactic loop as well.

  adjunct_asset_count_minus1: A value one less than the number of auxiliary assets described in the next syntax loop. Up to 256 auxiliary assets can be displayed. When the number of auxiliary assets having the same adjuct_asset_type exceeds 256, it should be described using two or more syntax loops.

  adjunct_asset_id: A 48-bit globally unique identifier that identifies an auxiliary asset. Here, uniqueness is maintained only for a certain period of time, and after a certain period of time, the identifier is reusable. In order to be a global identifier, this field is divided into two parts: a 32-bit provider identifier (provider_identifier) and a 16-bit asset identifier (asset_identifier). The provider identifier designates the registration authority and registers by provider, and the asset identifier is managed by the provider.

execution_attribute: Contains various fields that indicate how to execute when the receiver receives an auxiliary asset.
execution_on_reception: A flag indicating whether or not to "execute immediately" after storing the received auxiliary asset in the auxiliary asset cache inside the receiver. If it is not performed immediately, it may be performed at a time designated by the synchronization method proposed by the present invention, or it may be performed by user selection or a call from other auxiliary asset. If the value of this flag is 1, execution_entry_point is also set to 1.

  media_service_bound: A flag indicating whether the auxiliary asset is media_service_bound. When the value of this flag is “1”, it indicates that the supplementary asset belongs to this media service, and the supplementary asset is automatically ended when the broadcast channel is switched.

  execution_entry_point: A flag indicating that the auxiliary asset can be directly executed. When the value of this flag is “0”, the auxiliary asset is indirectly implemented by another auxiliary asset.

  visible_to_user: When the user can select and implement selection utilizing auxiliary asset navigation function, or when other auxiliary assets search the auxiliary asset list via API (Application Programming Interface) provided by the receiver A 2-bit field that indicates whether to make it visible or not. The meaning of visible_to_user is as shown in Table 15 below.

secure_execution: 2-bit information indicating whether the auxiliary asset is secure or not. The meaning of secure_execution is as shown in Table 16.
adjunct_asset_priority: A field that indicates the auxiliary asset implementation priority. The higher the value of adjunct_asset_priority, the higher the priority. If there are not enough receiver resources to execute the supplementary asset, temporarily abort or terminate the currently executing supplementary asset with the lowest priority.

adjunct_asset_locator_count_minus1: A value one less than the number of locations to read auxiliary assets. It can be shown up to four places as 2 bits. If two or more locations are provided, the priority is based on the order in which the adjunct_asset_locator appears. One or more adjunct_asset_locators always appear.
adjunct_asset_locator: Announces information on where to read auxiliary assets.

adjunct_asset_descriptor_loop_length: The number of bytes following this field to the last byte of the descriptor syntax loop.
adjunct_asset_descriptor: This descriptor syntax loop can contain various descriptors.
CRC_32: a field identical to CRC_32 defined in the section syntax of the MPEG-2 system standard (ISO / IEC 13818-1: 2007).

  Resource data location information, adjunct_asset_locator, indicates where to read the supplementary asset. Auxiliary assets are either transmitted via the broadcast network carrousel or downloaded via the Internet. AAT must include at least one adjunct_asset_locator per supplementary asset. The receiver first reads the supplementary asset from the position designated by the appearing adjunct_asset_locator, and when an error occurs, reads the supplementary asset from the position designated by the next adjunct_asset_locator.

  The syntax of adjunct_asset_locator is as shown in Table 17, and the meaning of each field is defined below. Table 17 includes only the case of the Internet, and in the case of carrousel, it differs depending on the carrousel system described in ISO / IEC 13818-6: 1998. Therefore, specific items are not included in Table 17.

  locator_type: An 8-bit field that indicates whether the auxiliary asset is read from the Internet or a broadcast network carrousel, and that the position is carrousel, and what kind of carulose is used when various types of carulose are used together .

locator_prefix_index: An index specifying one of locator_prefix of Table 14. If the value of this field is "OxFF", it indicates that there is no locator_prefix.
directory_path_length: Length of the next directory path. The final null byte of the text string is not included. If the value of this field is "0", no directory path is used.

directory_path_byte: byte of directory path. The final null byte of the text string is not included.
entry_path_length: The length of the path following the first page file. The final null byte of the text string is not included. It has meaning only in the case of auxiliary assets composed of a large number of files, such as web pages. If the auxiliary asset is a single file, the value of this field is '0'.

entry_path_byte: The byte of the path following the first page file. The final null byte of the text string is not included.
object_count: Number of next file path. If the value of this field is "0", specify the entire directory.
object_path_length: Length of text string of next file path. The last null byte of the text string is not included.
object_path_byte: byte of file path. The final null byte of the text string is not included.

  As described above, the adjuct_asset_descriptor in Table 14 can include various descriptors. These descriptors are handler_capability_descriptor () indicating the ability of the receiver to process auxiliary assets, adjunct_asset_cache_descriptor () indicating the amount of memory required for managing the auxiliary asset cache, etc., and the number of auxiliary assets displayed on the screen It may include display_position_descriptor () indicating the position on the display, adjunct_asset_name_descriptor () announcing an auxiliary asset name shown to the user, adjunct_asset_icon_descriptor () announcing an icon of an auxiliary asset shown to the user, and the like.

  The PGT_reference_descriptor conveys the PGT version and location reference information. It may be included in the SMT_M_descriptor syntax loop, or in the SMT_S_descriptor syntax loop (SMT_S_descriptor is used for the descriptor in the PPT_body () syntax element group included in SMT-S). If PGT_reference_descriptor is not included in SMT-M or SMT-S, it is considered that the service does not provide package guide information.

The syntax of PGT_reference_descriptor is as shown in Table 18, and the meaning of each field is defined below.

descriptor_tag: A unique value indicating the type of this descriptor.
descriptor_length: The number of bytes from the next to this field to the last byte of this descriptor.
PGT_provider_id: A unique identifier of an institution providing a PGT. One organization can provide one PGT, and PGT_provider_id is assigned via the registration authority.

PGT_update_version: A version number indicating whether or not PGT content is changed, and this value is increased by one when the content of PGT is updated. After the maximum value 255, it is reset to 0. If the PGT version number stored by the receiver is different from this value, the receiver rereads the PGT and decrypts the content.
number_of_locations: The number of PGT locations provided to this descriptor. The location of the PGT with the same updated version follows this field.
MMT_general_location_info (): Specify a PGT location.

  MMT_general_location_info () is general location reference information, and its syntax and definition are shown in Table 5. If there is one or more MMT_general_location_info () in this descriptor, the receiver tries access in the order of the list of MMT_general_location_info ().

  MMT_composition_descriptor provides spatial screen layout information of an asset (including a PPT asset) belonging to a certain package based on SMIL. This descriptor may be used to provide screen layout information if the screen layout does not change during the playback section of a certain package. This descriptor may be included in the SMT_S_descriptor syntax loop or in the PPT_descriptor syntax loop (PPT_descriptor is used for the descriptor in the PPT_body () syntax element group included in the PPT).

The syntax of MMT_composition_descriptor is as shown in Table 19, and the meaning of each field is defined below.

descriptor_tag: A unique value indicating the type of this descriptor.
descriptor_length: The number of bytes from the next to this field to the last byte of this descriptor.
version: When the package composition information is changed, the value of this field is incremented by one and reset to 0 after the maximum value 255.
compression_type: Compression method for package composition information. When the value of this field is "0", it indicates that the package composition is not compressed, and when it is "1", it indicates that the package composition is compressed by GZIP. Other values are reserved values for later use.
XML_length: The byte length of package composition information.
XML_package_composition_byte: byte of package composition information. The definition of package composition information is described in ISO / IEC JTC 1 / SC 29 / WG 11m19266.

  The alternate_package_descriptor is used when the viewer uses the alternative package to subsequently watch the live broadcast interrupted by the regular organization, or when only the second half of the entire event (eg, golf relay) is broadcast live, It is a descriptor that allows parties to view the event from scratch using an alternative package. Also, the alternate_package_descriptor may be used as an alternative package for an entire package (that is, from start to end) regardless of the availability of this live relay.

  The MMT_package_descriptor may be included in the SMT_S_descriptor syntax loop or in the PPT_descriptor syntax loop. If the location of the alternative package is a large number of locations, multiple alternate_package_descriptors may be included in the MMT_package_descriptor.

  The purpose, usage scenario, definition and usage method of this descriptor are described in Korean Patent Application No. 2011-0095665. In this specification, for convenience of explanation, the syntax of alternate_package_descriptor is shown in Table 20, and the meaning of each field is defined below.

descriptor_tag: An 8-bit field indicating the type of this descriptor. A unique value is assigned to indicate that it is an alternative program descriptor so that it can be distinguished from other descriptors defined in the MPEG-2 system standard or a broadcast standard using it.
descriptor_length: An 8-bit field indicating the length of this descriptor in bytes. Indicates the length from the next byte of this field to the last byte of the descriptor.

  alternate_program_id: An 8-bit field corresponding to an alternate program identifier. If alternate programs described by alternate_program_descriptor are different from each other, different alternate_program_ids are assigned. In the case of guiding the alternative program to be watched before actually starting the live relaying, the guide information can be periodically transmitted several times for the same alternative program. In such a case, the same alternate_program_id is subsequently used. If you use all the values from 0 to 255, you may reuse the values already used.

reserved: As a field reserved for later use, its value is filled with 0x7F.
just_alternate_flag: Indicates that the content included in this descriptor is for an alternate package of a package (whether or not it is for live relay) containing this descriptor. If the value of this flag is "1", future_flag has no meaning and text_length is always "0".

  future_flag: a 1-bit field indicating whether the content included in this descriptor is for an alternative program to be viewed in advance or for an alternative program to be viewed continuously after the end of the current program. If the value of this field is “1”, it indicates an alternative program to be viewed in advance, and if it is “0”, it indicates an alternative program to be viewed subsequently after termination.

time_to_future_live_program: A 16-bit field indicating the time, in seconds, until live relay is started via this program channel, when the future_flag is “1”.
If the value of this field is 0x0000, it means that immediate live relay has been started or has already been started. This value can be used to return to the live broadcast program of the broadcast channel from the internet live broadcast service of the alternative package. If the value of this field is OxFFFF, it indicates that it is impossible to know the time until the live relay is started via this channel. This value substitutes for an event that will be broadcast live via this program channel via live Internet relay service, but does not know when the live broadcast will be started via this program channel Use for

MMT_general_location_info (): General location reference information defined by MMT, whose contents are shown in Table 5.
text_length: an 8-bit field indicating the number of next text_byte. A value of 0x00 indicates that there is no text string that describes the alternative program.
text_byte: A byte that constitutes a text string describing an alternative program. This field does not contain a null byte at the end.

  extension_descriptor (): A descriptor corresponding to an option that transmits additional information, and an 8-bit tag value identifying the type is uniquely identified only in the alternate_package_descriptor, It is the first byte of these descriptors. This field is followed by an 8-bit value indicating the length of the descriptor.

  The alternate_program_descriptor has the same contents as the 16-bit alternate_package_descriptor except that the size of the descriptor_tag and the descriptor_lenth is 8 bytes, and the value of the descriptor_tag is assigned as the MPEG-2 descriptor tag value. That is, the alternate_program_descriptor is obtained by modifying the alternate_package_descriptor as an MPEG-2 descriptor.

  The alternate_program_descriptor is used for the purpose similar to the alternate_package_descriptor, but is included in the descriptor syntax loop following the program_info_length of the MPEG-2 PMT. For MPEG-2 TS based MPEG-DASH, this descriptor may be included directly in PMT.

  The language_descriptor is used to specify the language for assets for which the language needs to be specified. For example, assets corresponding to audio, subtitles, screen commentary broadcasting, etc. need to specify in what language they were created. language_descriptor may be included within PPT's PPT_descriptor syntax loop or asset_descriptor syntax loop, and within SMT_S_descriptor syntax loop or asset_descriptor syntax loop within SMT-S. When this descriptor is included in the PPT_descriptor or SMT_S_descriptor syntax loop, the language of all assets in the package is specified by this descriptor. When this descriptor is included in the asset_descriptor syntax loop, the language of the asset is specified by this descriptor. The content of the descriptor applied to the asset takes precedence over the content of the descriptor applied to all the assets of the package. In this specification, the syntax of language_descriptor is shown in Table 21 for the convenience of description, and the meaning of each field is described below.

descriptor_tag: A unique value indicating the type of this descriptor.
descriptor_length: The number of bytes from the next to this field to the last byte of this descriptor.
ISO_639_language_code: A 3-byte language identifier according to the ISO 639 standard.

  The clock_reference_descriptor is used to notify the receiver of the relationship between the encoder clock for media synchronization and the MMT system clock. In MMT, UTC (Network Time Protocol) format UTC is used as a system clock, and an asset encoder clock allows different clocks to be used for each asset. The clock used by the asset encoder is identified by clock_reference_id.

  The clock_reference_descriptor must be periodically transmitted within a cycle of 100 mS, and is transmitted to a separate asset. In this specification, the syntax of clock_reference_descriptor is shown in Table 22 for the convenience of description, and the meaning of each field is defined below.

descriptor_tag: A unique value indicating the type of this descriptor.
descriptor_length: The number of bytes from the next to this field to the last byte of this descriptor.

clock_reference_id: an identifier of a clock used by the asset encoder.
encoder_clock_sample: The value of asset clock sample corresponding to the following system_clock_time.
encoder_clock_sample: A value of UTC time in NTP format as an MMT system clock time corresponding to the preceding encoder_clock_sample.

FIG. 5 shows an S1 signaling structure according to one embodiment of the present invention.
Organizing six S1 layer messages according to another embodiment of the present invention is as follows.

(1) Message about Information on Tables and Notice (ITN):
Such messages convey ITN tables and other tables that can additionally be used for fast access to the package. The role of ITN is similar to MPEG-2 PAT but with other MMT specific functions. The ITN table contains full information about all other S1 tables. Also, the ITN has information on receipt of the notification. Typical examples of notification are emergency alert, emergency notification, etc.

(2) Message about MMT Composition Information (MCI):
Such messages convey MMT CIs. This transmits not only full CIs but also hierarchical CIs.

(3) Message about Clock Reference Descriptors (CRD):
Such messages carry clock reference information used for mapping between the MMT system clock (i.e., NTP clock) and any other clock (e.g., MPEG-2 or MPEG-4 clock).

(4) Messages for Security Information:
Such messages carry security information used to protect MMT content. The security system is DRM, downloadable DRM, and downloadable condition rating system (D-CAS) information.

(5) Messages on MMT Package Table (MPT) (Messages for MMT Package Table, MPT):
Such messages carry the MMT Package Table (MPT). Perfect or Tier-0 MPT corresponds to the MMT package. This is the package's global unique identifier, the location of the MMT composition information (MCI), and a complete or partial (possibly hierarchical MPT is used) list of MMT assets belonging to the MMT package including. It also includes package type, package name, package short description, parental rate, audio language, text language, target user profile, requested device capabilities, recording permissions and fast play permissions Package policies, etc. The role of MPT is similar to MPEG2 PMT, but with more functionality for MMT purpose.

(6) Messages for Device Capability Information Table (Messages for Device Capability Information Table):
Such messages carry a Device Capability Information Table (DCIT). The device capability information provides device capabilities for requests and / or recommendations for MPEG media content consumption.

Furthermore, the following three descriptors are defined:
(1) Language descriptor
(2) Clock reference descriptor
(3) D-CAS descriptor (D-CAS descriptor)

  In the following, referring to FIG. 5, the syntax and meaning of S1 hierarchical messages, tables and descriptors according to another embodiment of the present invention will be defined.

1. S1 Hierarchical Messages, Tables, and Syntax and Meaning of Descriptors 1.1 Information Tables and Messages for Information of Notification (ITN) Such messages carry the ITN table 505. The role of ITN is similar to MPEG-2 PAT but with other MMT specific functions. The ITN table contains full information about all other S1 tables.
Also, the ITN has information on notification reception. Typical examples of notification are emergency alert, emergency notification, etc.

The ITN message, ie the message comprising the ITN table, may further comprise one or more MMT Package Tables (MPT) corresponding to the MMT package. The MPT is the package's globally unique identifier, the location of the MMT composition information (MCI), and the complete or partial list of MMT assets belonging to the MMT package (if possible, layered MPT is used) including. Also, MPT includes package type, package name, package short description, parental rate, audio language, text language, target user profile, requested device capabilities, recording permission and fast play permission Includes package policy etc.
If the ITN message contains only one MPT, the media delivery service provides the user with only one package at any given fixed time instant. When the ITN table contains multiple MPTs with arbitrary duplication in time series, the media delivery service provides multiple packages to the user at any fixed time instant. If the ITN table has no time overlap and the corresponding package contains multiple MPTs associated with the same logical channel, the media delivery service provides multiple packages to the user in sequential time order.

  S-tier messages with MessageID = 0x00 should include the ITN table. Also, the payload_id of the asset path in the IP application data flow transmitting the S-layer message having MessageID = 0x00 is fixed at “0x0000”. The receiver should read and decrypt the ITN message before reading any other message.

  ITN messages are typically sent periodically in a very short period, eg, 500 ms, in a broadcast environment to ensure short power up delays or low zapping times.

1.1.1 ITN Message Syntax and Meanings The syntax of ITN messages is defined in Table 23, and the meaning of this syntax element is provided in Table 23 below. The syntax definition method is based on the method of the MPEG-2 system standard (ISO / IEC 13818-1). In the "value" column, the indication of no loop count can be derived from the length of the table. The same rules apply to other tables herein.

message_id: Indicates the type of S layer message. The length of this field is 8 bits. The ITN message has a fixed message_id with the value 0x00.
version: version of S-tier message. The MMT client can determine if the received S-layer message is new. In particular, this field is useful when S-layer messages are repeatedly transmitted over the broadcast network. The length of this field is 8 bits.

  length: Length of S1 layer message. The length of this field is 16 bits. This indicates the length of the ITN message counted in bytes starting from the next field to the last byte of the ITN message. The value "0" is not used at all for this field.

start_time_flag: If the value of this flag is "1", an additional syntax element start_time is used.
start_time: Start time at NPT of ITN message transmission.
retransmission_period: The retransmission time of the ITN message. The unit of retransmission_period is 10 ms.
number_of_tables: Number of tables included in this ITN message.
table_id: Table identifier of the table included in this ITN message. This is a copy of the table_id field in the table contained in the payload of this ITN message.
table_version: Version of the table included in this ITN message. This is a copy of the version field in the table contained in the payload of this ITN message.
table_length: The length of the table included in this ITN message. This is a copy of the length field in the table contained in the payload of this ITN message. The actual length of the table is table_length + 4.
table (): S hierarchical table. The tables in the payload are shown in the same order as the table_id in the extension field.

1.1.2 Syntax and Meaning of ITN Table The syntax of the ITN table is defined in Table 24, and the meaning of its syntax elements is provided below Table 24.

table_id: Table identifier of ITN table.
version: version of ITN table. Newer versions override older versions as soon as they are received.
length: The length of the ITN table counted in bytes starting from the next field to the last byte of the ITN table. The value "0" is never used for this field.

  method_flag: Indicates a method of receiving a notification. When the value of this flag is "0", the notification is transmitted by IP broadcast transmission. When the value of this flag is "1", a notification is communicated via the interaction channel. An IP address and IP port number are provided for IP broadcast transmission. A URL is provided that allows the client to poll for notifications via the interaction channel for communication via the interaction channel.

MMT_general_location_info (): General location reference information defined in Table 25 in Section 1.1.3. The actual location depends on the syntax element location_type in MMT_general_location_info ().
MMT_general_location_info () for IP_broadcast_delivery: Only location_type = 0x14 and 0x15 are allowed for IP_broadcast_delivery.
MMT_general_location_info () for poll_URL: Only location_type = 0x0E is allowed for poll_URL.

poll_period: While polling for notifications, it is expected that the client or receiver poll for the notification URL, poll_URL, all poll_period seconds.
number_of_tables: The number of information tables for which information is provided in this ITN table.
information_table_id: identifier of an information table for which information is provided in this ITN table. The ITN table_id never appears here.
information_table_version: version of the information table for which information is provided in this ITN table.

  package_path_number: Identifier of the logical channel to which the information table belongs. The broadcaster uniquely assigns an identifier to the logical channel in the physical channel. The value "0" has a special usage and is not used as an identifier. If the value of this field is '0', the information table is channel independent, ie the information table has service-wide information.

MMT_general_location_info () for location: The address from which the client acquires the information table. Only location_type = 0x0F to 0x13 are allowed.
second_location_flag: If this flag is set, an alternate address is provided for the client to obtain the information table.
table_filter_code_flag: When this flag is set, one or more table filter codes are provided. The table filter code specifies the criteria for grouping a plurality of tables. When there are many criteria to be grouped at the same time, all grouping criteria are applied to the information table.

MMT_general_location_info () for second_location: Alternate address from which the client gets the information table. Only 0x0F to 0x13 are allowed.
number_of_table_filter_codes: Number of table filter code for information table.
language_for_all_table_filter_codes: The language of all immediately following table_filter_codes. The language code is a 3-byte language identifier defined in the ISO639 standard.

  table_filter_code_language_flag: If the value of this flag is “1”, the language for the subsequent table_filter_code is separately identified and overrides the language provided by language_for_all_table_filter_codes. The language code is a 3-byte language identifier defined in the ISO639 standard.

table_fileter_code_language: language of table_filter_code immediately following. The language code is a 3-byte language identifier defined in the ISO639 standard.
table_fileter_code_length: The byte length of table_filter_code.
table_fileter_code_byte: byte in table_filter_code.
private_extension_flag: A private extension exists when the value of this flag is "1".
private_extension (): Syntax element group that acts as a container for proprietary or application specific extensions.

1.1.3 MMT_general_location_info () syntax element group
The MMT_general_location_info () syntax element group is used to provide location information. The syntax of MMT_general_location_info () is defined in Table 25 and the meaning of that syntax element is provided below Table 25.

location_type: This field indicates the type of location information as defined in Table 26.

payload_id: Unique asset path identifier in IP application data flow.
ipv4_src_addr: IP version 4 source address of IP application data flow.
ipv4_dst_addr: IP version 4 destination address of IP application data flow.
dst_port: IP application data flow destination port number.
ipv6_src_addr: IP version 6 source address of IP application data flow.
Ipv6_dst_addr: IP version 6 destination address of IP application data flow.

network_id: identifier of a broadcast network transmitting an MPEG-2 TS.
MPEG_2_transport_stream_id: MPEG-2 TS identifier.
MPEG_2_PID: PID of an MPEG-2 TS packet.
prefix_index: Index to the prefix defined before this syntax element group. If the value of this field is OxFF, no prefix is used.

URL_length: The length of URL in bytes. The final null (0x00) must not be counted.
URL_byte: byte data in URL. Final null (0x00) must not be included.
byte_offset: byte offset from the first byte of the file.
length: Length in bytes.
message_id: S layer message identifier.
Ipv4_addr: IP version 4 address of IP application data flow.
Ipv6_addr: IP version 6 address of IP application data flow.

1.2 MMT Composition Information (CI) Messages MMT Composition Information (CI) is conveyed by CI messages for out-of-band signaling. CI messages can convey perfect CIs or layered CIs. When layered CIs are conveyed, it is most recommended to transmit layer-0 CIs by means of ITN messages in order to reduce the time required for package consumption in a broadcast scenario. When a Tier-0 CI is transmitted in an ITN message as reference numeral 510, the CI needs to be encapsulated in the MCI (MMT Composition Information) table before being included in the ITN message.

  When a layered CI mechanism is utilized, Tier-N CIs (where N is not 0) are generally transmitted in CI messages having different repetition rates and different message identifiers.

1.2.1 CI message syntax and semantics The syntax of the CI message is defined in Table 27, and the semantics of its syntax elements are provided below in Table 27.

message_id: Indicates the type of S layer message. The length of this field is 8 bits. The S-tier messages need to have separate message_ids when transmitting CIs on separate CI tiers for separate packages.
version: version of S-tier message. The MMT client can determine if the received S-layer message is new. In particular, this field is useful when S-layer messages are repeatedly transmitted over the broadcast network. The length of this field is 8 bits.
length: Length of the S layer message. The length of this field is 16 bits. This indicates the length of the CI message counted in bytes starting from the next field to the last byte of the CI message. The value "0" is never used for this field.
start_time_flag: If the value of this flag is "1", an additional syntax element start_time is used.
start_time: Start time at NPT of CI message transmission.
retransmission_period: Retransmission time of this CI message. The unit of retransmission_period is 10 ms.
CI_byte: byte in CI.

1.2.2 MCI Table Syntax and Meaning The syntax of the MCI table is defined in Table 28, and the meaning of its syntax elements is provided below in Table 28. MCI tables should only be used for perfect CIs or Tier-0 CIs.

table_id: Table identifier of the MCI table.
version: MCI table version. Newer versions override older versions as soon as they are received.
length: The length of the MCI table counted in bytes starting from the next field to the last byte of the MCI table. The value "0" is never used for this field.
CI_byte: byte in CI.

1.3 Clock Reference Descriptor (CRD) Messages The clock reference descriptor defined in 1.7.2 is conveyed in the CRD message. One CRD message may contain multiple clock reference descriptors.

  When the clock reference descriptor is transmitted in the ITN message, it should be encapsulated in a table structure called CRD table 520.

1.3.1 CRD Message Syntax and Meaning The syntax of the CRD message is defined in Table 29, and the meaning of its syntax elements is provided below Table 29.

message_id: Indicates the type of S layer message. The length of this field is 8 bits.
version: version of S-tier message. The MMT client can determine if the received S-layer message is new. In particular, this field is useful when S-layer messages are repeatedly transmitted over the broadcast network. The length of this field is 8 bits.
length: Length of the S layer message. The length of this field is 16 bits. This indicates the length of the CI message counted in bytes starting from the next field to the last byte of the CI message. The value "0" is never used for this field.
start_time_flag: If the value of this flag is "1", an additional syntax element start_time is used.
start_time: Start time in NTP of CRD message transmission.
retransmission_period: Retransmission time for this CRD message. The unit of retransmission_period is 10 ms.
clock_reference_descriptor (): is defined in 1.7.2.

1.3.2 CRD Table Syntax and Meaning The CRD table syntax is defined in Table 30, and the semantics of its syntax elements are provided below Table 30. The MCI table should only be used for perfect CIs or Tier-0 CIs.

table_id: CRD table identifier.
version: CRD table version. Newer versions override older versions as soon as they are received.
length: Length of the CRD table counted in bytes starting from the next field to the last byte of the CRD table. The value "0" is never used for this field.
clock_reference_descriptor (): is defined in 1.7.2.

1.4 Security messages Security information is transmitted within security messages or ITN messages. When security information is transmitted in the ITN message as reference numeral 525, it should be encapsulated before being included in the ITN message.

1.4.1 Syntax and Meaning of Security Messages The syntax of security messages is defined in Table 31 and the meaning of the syntax elements is provided below Table 31.

message_id: Indicates the type of S layer message. The length of this field is 8 bits.
version: version of S-tier message. The MMT client can determine if the received S-layer message is new. In particular, this field is useful when S-layer messages are repeatedly transmitted over the broadcast network. The length of this field is 8 bits.
length: Length of the S layer message. The length of this field is 16 bits. This indicates the length of the CI message counted in bytes starting from the next field to the last byte of the CI message. The value "0" is never used for this field.
start_time_flag: If this flag is "1", an additional syntax element start_time is used.
start_time: Start time at NPT of security message transmission.
retransmission_period: Indicates the retransmission time of this security message. The unit of retransmission_period is 10 ms.
Security_descriptor (): Defined in 1.7.3.

1.4.2 Security Table Syntax and Meaning The syntax of the security table is defined in Table 32, and the meaning of its syntax elements is provided below Table 32.

table_id: Security table identifier.
version: Security table version. Newer versions override older versions as soon as they are received.
length: The length of the security table counted in bytes starting from the next field to the last byte of the security table. The value "0" is never used for this field.
security_descriptor (): defined in 1.7.2.

Message for 1.5 MPT (MMT Package Table) Referring to FIG. 5, the MMT Package Table (MPT) conveys all the information about a single package. An S-layer message that transmits an MPT is called an "MPT message". The MPT may be included in the ITN message with other tables as reference numeral 515 and may be transmitted in a separate MPT message.

  For layered transmission of packages with layered CIs, the MPT can be partitioned into multiple layered MPTs. Layer-0 MPT is the basic MPT, and only layer-0 MPT is transmitted if hierarchical transmission is not used. In the latter case, the hierarchy-0 MPT is a perfect MPT. The MPTs in different layers need to have different table identifiers (table_ids). In this standard, eight different values for MPTtabe-id were assigned so that up to eight MPT layers can be included. The smaller the value of MPTtable_id, the closer the MPT layer is to the basic MPT.

  In order to reduce package acquisition time in broadcast scenarios, it is most recommended to transmit a perfect MPT or layer-0 MPT when layered MPTs are used in ITN messages.

1.5.1 MPT Message Syntax and Meaning The syntax of the MPT message is defined in Table 33, and the meaning of its syntax elements is provided below Table 33. The MPT message transmits only one complete MPT or layer-N MPT when MPT layering is used.

message_id: Indicates the type of S layer message. The length of this field is 8 bits.
version: version of S-tier message. The MMT client can determine if the received S-layer message is new. In particular, this field is useful when S-layer messages are repeatedly transmitted over the broadcast network. The length of this field is 8 bits.
length: Length of the S layer message. The length of this field is 16 bits. This indicates the length of the MPT message counted in bytes starting from the next field to the last byte of the MPT message. The value "0" is never used for this field.
start_time_flag: If the value of such flag is "1", an additional syntax element start_time is used.
start_time: Start time at NPT of MPT message transmission.
retransmission_period: Retransmission time for this MPT message. The unit of retransmission_period is 10 ms. When layered MPTs are used, the retransmission_period of the upper layer MPT is generally longer than the retransmission_period of the MPT layer below the upper layer MPT.
MMT_package_table () is defined in 1.5.2.

1.5.2 MPT Syntax and Meanings The syntax of MPT () is defined in Table 34, and the meaning of its syntax elements is provided below Table 34.

table_id: MPT table identifier. The MPTs in different tiers need to have different table identifiers. Eight different values are assigned to MPTtable_id. Among the eight MPTtable_ids, when layered MPTs are used, the table_id for the perfect MPT or hierarchy-0 MPT is the smallest. For the remaining MPTtable_id, lower values mean lower hierarchical MPT.
version: MPT version. Newer versions override older versions as soon as they are received.
length: The length of the MPT counted in bytes starting from the next field to the last byte of the ITN table. The value "0" is never used for this field.
MMT_package_id: A globally unique identifier of the MMT package.
MPT_descriptors_length: Length of descriptor syntax loop. This length is counted from the next field to the end of the descriptor syntax loop. Various descriptors can be inserted into this syntax loop.
MPT_descriptors_byte: 1 byte in the descriptor loop.
package_type: Indicates the type of package. Acceptable values are shown in Table 35.

package_name: Package name in multiple languages, if possible. The language code is a 3-byte language identifier defined in the ISO639 standard. The first language in the list is the default.
package_description: Syntax description of the package in multiple languages, if possible. The language code is a 3-byte language identifier defined in the ISO639 standard. The first language in the list is the default.
audio_languages: Audio languages (multiple languages) used in the package. The language code is a 3-byte language identifier defined in the ISO639 standard. The first language in the list is the default.

text_languages: Text language (multiple languages) used in the package. The language code is a 3-byte language identifier defined in the ISO639 standard. The first language in the list is the default.
target_user_profiles: Profiles (multiple profiles) of the user targeting the package.
required_device_capability_profiles: Profiles (multiple profiles) of device capabilities required for package consumption.

  parental_guidance_flag: If the value of this flag is '1', the rating information is that the receiver is allowed to indicate the content to what is set by the viewer for child protection (the transmission method is this standard Do not provide what will be decoded until you can ensure from (not currently identified). If the value of this flag is '0', the receiver does not check the rating but only provides what is to be decoded from this package.

recording_flag: If the value of this flag is “1”, the receiver can store it in the internal storage for subsequent use of this package.
fast_play_flag: If the value of this flag is '1', the receiver causes the viewer to command fast play of this package.
clock_reference_flag: If the value of this flag is '0', no clock_reference_id is provided and by default the MMT system clock is an NTP clock, ie the time base of all assets in this package is an NTP clock. If the value of this flag is "1", the clock_reference_id field is included next.

protection_scheme_id_flag: If the value of this flag is "1", the protection_scheme_id field is included next.
clock_reference_id: Clock reference identifier. This field is used to reference the clock conveyed by clock_reference_descriptor () as the default time base for all assets in this package. A value of 0 is not allowed for this field. There are two placeholders for the clock reference identifier in the MPT syntax. One (this field) applies to all assets in this package, and the other applies only to asset entries in syntax loops. The latter takes precedence if both of the fields are included in the MPT syntax.

timescale_flag: If the value of this flag is "1", the time scale field is included next.
timescale: The time unit for all time stamps used for all assets in this package, expressed in multiple units in 1 second. The default value is 90,000. There are two placeholders for the timescale field in the MPT syntax. One (this field) applies to all assets in this package, while the other applies only to asset entries in syntax loops. The latter takes precedence if both fields are included in the MPT syntax.

  protection_scheme_id: This field indicates the protection scheme used for all assets in this package. There are two placeholders for the protection scheme identifier field in the MPT syntax. One (this field) applies to all assets in this package, while the other applies only to asset entries in syntax loops. The latter takes precedence if both of the fields are included in the MPT syntax. The value of this field is one of DCAS_types specified by the D-CAS descriptor in 3.7.3.

protection_scheme_id_flag: If the value of this flag is "1", the protection_scheme_id field is included next.
MMT_general_location_info () for the general location reference information about MMT defined in the location: 1.1.3 for the CI location. Only the location_type = 0x0F to 0x13 is allowed for the CI location.
number_of_assets: The number of assets in this MPT.
asset_type: Asset type. This field is similar to stream_type defined in MPEG-2 PMT, but is an extension thereof.

  asset_id: Asset identifier. In CI, asset_id is used to refer to an asset. The asset_id defined in CI is globally unique. This field is a short alias for a globally unique asset identifier. Aliasing is done automatically by mapping the order of appearance of assets in the list of assets in CI (LoA). When CI layering is used, aliasing is performed within the ordered concatenation of all LoA from layer O to layer N. The asset_id alias must be represented incrementally in the asset information syntax loop within the MPT.

asset_clock_reference_flag: If the value of this flag is '1', the asset_clock_reference_id field is included in the following syntax.
asset_clock_reference_id: Clock reference identifier for the asset. This field is used to reference the clock conveyed by clock_reference_descriptor () as the asset's time base. If the value of this field is "0", NTP clock is used for the asset. If the value of this field is not "0", the value of this field is one of the clock_reference_id values provided by the clock reference descriptor.

asset_timescale_flag: If the value of this flag is "1", the asset_timescale field is included in the following syntax.
asset_timescale: The time unit for all time stamps used for assets represented in multiple units in 1 second. The default value is 90,000.
asset_protected_flag: This asset is protected if the value of this flag is "1".
asset_protection_scheme_id_flag: If the value of this flag is "1", the asset_protection_scheme_id field is included in the following syntax.

MMT_general_location_info () for the asset location: In 1.1.3, general location reference information of MMT defined in Table 3. Only location_type = 0x03, 0x05, and 0x07-0x0D are allowed for asset location.
asset_descriptors_length: The number of bytes counted from the next field to the end of the asset descriptor syntax loop.
asset_descriptors_byte: byte in asset descriptor.

1.6 Message about Device Capability Information Table (DCIT) DCIT provides device capability information. When transmitted in an ITN message, the DCIT 530 needs to be encapsulated in a table structure called a DCIT table.

1.6.1 DCIT Message Syntax and Meaning The syntax of the DCIT message is defined in Table 36, and the meaning of that syntax element is provided below Table 36.

message_id: Indicates the type of S layer message. The length of this field is 8 bits.
version: version of S-tier message. The MMT client can determine if the received S-layer message is new. In particular, this field is useful when S-layer messages are repeatedly transmitted over the broadcast network. The length of this field is 8 bits.
length: Length of the S layer message. The length of this field is 16 bits. This indicates the length of the MPT message counted in bytes starting from the next field to the last byte of the DCIT message. The value "0" is never used for this field.
start_time_flag: If the value of this flag is "1", an additional syntax element start_time is used.
start_time: Start time in NPT of DCIT message transmission.
retransmission_period: Retransmission time of this DCIT message. The unit of Retransmission_period is 10 ms. When layered MPTs are used, the retransmission_period of the upper layer MPT is generally longer than the retransmission_period of the MPT layer below the upper layer MPT.
MMT_package_table () is defined in 1.5.2.
DCIT (): Defined in 1.6.2.

1.6.2 DCIT Syntax and Semantics The syntax and semantics of DCIT are defined in Table 37.

1.7 Descriptor An S layer table and an association descriptor are defined.

1.7.1 Language Descriptors Language descriptors are used to identify media assets such as audio, commentary broadcasts, subtitles, etc. A language descriptor can be included in an MPT descriptor syntax loop or an asset descriptor syntax loop in MPT. When a language descriptor is included in the MPT descriptor syntax loop, this identifies the language of all assets in the package. When a language descriptor is included in an asset descriptor syntax loop in MPT, this specifies the language of the asset. The language descriptor included in the asset descriptor syntax loop in MPT has priority over the language descriptor included in the MPT descriptor syntax loop in MPT.

  The syntax of language_descriptor () is defined in Table 38, and the meaning of that syntax element is provided below Table 38.

descriptor_tag: Tag value indicating the type of descriptor.
descriptor_length: The length in bytes counted from the next byte of this field to the last byte of the descriptor.
ISO_639_language_code: 3-byte ISO639 language identifier.

1.7.2 Clock Reference Descriptor The clock reference descriptor is used to identify the relationship between the encoder clock for media synchronization and the MMT system clock. UTC in Network Time Protocol (NTP) format is used as MMT system clock time. MMT allows different clocks to be used for different assets. The clock used by the asset encoder is specified by clock_reference_id.

The clock_reference_descriptors must be transmitted periodically with a clock reference message having a short period, eg, 100 ms.
The syntax of clock_reference_descriptor () is defined in Table 39, and the meaning of that syntax element is provided below Table 39.

descriptor_tag: Tag value indicating the type of descriptor.
descriptor_length: The length in bytes counted from the next byte of this field to the last byte of the descriptor.
clock_reference_id: Media clock identifier used by the asset encoder. The value "0" is reserved for other purposes and is not used for clock_reference_id.
encoder_clock_sample: Media clock sampling value used by the asset encoder corresponding to the following MMT_system_clock_time.
MMT_system_clock_time: UTC time value in the NTP format corresponding to the preceding encoder_clock_sample.

1.7.3 Security Descriptors Security descriptors are used to identify security systems that can be used to protect MMT assets or packages.

Securtiy_descriptor should be periodically transmitted in a security message or an ITN message.
The syntax of security_descriptor () is defined in Table 40, and the meaning of that syntax element is provided below Table 40.

descriptor_tag: Tag value indicating the type of descriptor.
descriptor_length: The length in bytes counted from the next byte of this field to the last byte of the descriptor.
Security_type: Type of security solution. It presents access control, digital rights management, downloadable CAS or downloadable DRM solutions.
Solution: Indicates which security solution is used for access control, DRM, DCAS or DDRM.
Access_control_server_address: The address of the access control security solution server where the client has been authenticated and authorized.
DRM_server_address: The address of the DRM solution server where the client is authenticated and authorized.
DCAS_server_address: Address of DCAS server where clients can download DCAS SW after authentication and authorization.
DDRM_server_address: The address of the DDRM server where clients can download the DDRM SW after authentication and authorization.

  6 and 7 are flowcharts illustrating the operation of multimedia reception in a receiver according to an embodiment of the present invention.

  6 and 7, first, in step 615, the receiver receives the S1 message transmitted on the current channel. The S1 message is a message for managing all functions required for consumption of MMT assets and MMT items.

  The receiver determines in step 617 based on the message ID whether it is an ITN message included in the found S1 message. For other messages that are not ITN messages, the receiver determines in step 627 whether the other message has been updated. If it is another message that has been updated, the receiver stores, in step 629, version information of the other message that has been updated and the other message that has been updated in the memory. In contrast, if it is not an updated other message, the receiver proceeds to step 631.

  On the other hand, from the result of the determination in step 617, in the case of the ITN message, the receiver determines in step 619 whether or not the ITN message included in the found S1 message has been updated based on the version information. If so, the receiver determines in step 621 whether at least one table (i) in the ITN message has been updated. If it has been updated, the receiver stores the updated at least one table and its version information in the memory of the receiver in step 623, and proceeds to step 625. If at least one table (i) in the ITN message has not been updated, the receiver proceeds to step 625. Similarly, if it is determined in step 619 that the ITN message is not updated, the receiver proceeds to step 625.

  At step 625, the receiver examines all the tables. The receiver proceeds to step 631.

  As a result of the examination, the receiver determines in step 631 whether or not the CI tier 0 has been updated.

  If CI tier 0 is updated, the receiver sets CI tier 0 as an integrated CI in step 633. The receiver then proceeds to step 635. If the CI hierarchy 0 is not updated, the receiver proceeds to step 643.

  In step 635, the receiver determines whether the version of CI layer i is identical to the version of CI layer 0. If not, the receiver proceeds to step 641. Also, if they are identical, the receiver combines the CI layer i with the integrated CI in step 637. The receiver determines in step 639 whether it has checked all of the CI tiers. If all the tests have been completed, the receiver transmits the integrated CI to the CI analyzer in step 641. For example, if it is determined at step 639 that the receiver has checked all CI hierarchies, the receiver proceeds to step 641. On the other hand, if the receiver determines in step 639 that it has not completed examination of all CI layers, the receiver returns to step 635.

  At step 643, it is determined whether the MPT tier 0 has been updated. For example, if MPT layer 0 is not updated, the receiver terminates this process. On the other hand, if updated, the receiver sets MPT layer 0 as an integrated MPT in step 645. The receiver then proceeds to step 647.

  The receiver determines in step 647 whether the version of MPT layer i is identical to the version of MPT layer 0. For example, the receiver proceeds to step 653 if the layers are not identical. If so, the receiver combines MPT layer i with the integrated MPT in step 649. The receiver determines in step 651 whether it has checked all MPT layers. If all the inspections are completed, the receiver uses the asset reference in the integrated MPT to locate the asset in the package and transmit the found asset to the asset decoder or asset handler. For example, if the receiver determines in step 651 that all the MPT hierarchy checks have been completed, the receiver proceeds to step 653. In contrast, if the receiver determines that the test is not complete, the receiver proceeds to step 647.

FIG. 8 is a block diagram of a transmitter according to an embodiment of the present invention.
The service providing server 800 includes a service data providing unit 801, a package generation unit 803, and a transmission unit 805 as an example of a transmission apparatus. Although not shown in the drawings, it will be apparent to those skilled in the art to provide a control that can control the components of the transmitter to perform the operations of the embodiments of the present invention.
The service data providing unit 801 has all service sources.

The package generation unit 803 generates a package using the table described with reference to FIGS. 3 and 5.
The transmission unit 805 transmits the generated package to the terminal.
Also, the transmitting unit 805 may transmit the generated package to the terminal via a network of two different physical characteristics, a broadcast network and a broadband network.

FIG. 9 is a block diagram of a receiver according to an embodiment of the present invention.
The receiving device may be, for example, a terminal, but is not limited to this.

  The receiving apparatus 900 includes a receiving unit 901, a package analysis unit 903, and a decoder / playback unit 905. Although not shown in the drawings, it is apparent to those skilled in the art that the receiving device or terminal includes a control unit capable of controlling its components in order to perform the operation of the embodiment of the present invention. It is.

  The receiving unit 901 receives a package generated using the table described with reference to FIGS. 3 and 5 according to an embodiment of the present invention.

The package analysis unit 903 analyzes the components of the received package.
The decoder / playback unit 905 decodes and plays back the content based on the components of the analyzed package.

  Also, although not shown in the drawings, data may be recorded, stored and reproduced according to a package generated in accordance with an embodiment of the present invention. MMT asset, configuration information (Configuration information), composition information (Composition information), transport characteristics (Transport Characteristics), package identification information (Package) in one package on a storage medium (eg, CD, DVD, DB, USB, etc.) Identification information), asset list information (Asset list information), rights management information (Rights Management Information), transport schedule information (Transport Timeline Information), etc. are stored to be stored, and the content is It can be played back. When storing and reproducing via a storage medium, storing and reproducing can be made more easily by replacing the URL with storage location information (for example, memory address etc.) in the description of the embodiment.

  The various embodiments described above are understood to be illustrative examples of the present invention. All of the features described in connection with any one of the various embodiments described above can be used alone or in combination with other features described, and the various embodiments Can be used in combination with one or more features of the other embodiments, or can be used in combination with other embodiments of the various embodiments. While the present invention has been illustrated and described with reference to specific embodiments, it is to be understood that within the spirit and scope of the present invention as defined by the appended claims and equivalents thereof. It will be apparent to those skilled in the art that various modifications are possible, as well as details.

800 service providing server 801 service data providing unit 803 package generation unit 805 transmission unit 900 reception device 901 reception unit 903 package analysis unit 905 decoder / reproduction unit

Claims (2)

A multimedia content receiving device,
A receiver for receiving a packet including a header and a payload;
A control unit, included in the payload, for identifying a control message associated with the package configuration of multimedia content;
The control message is
A control message payload comprising a table containing specific information related to the multimedia content;
Type information of the control message;
Information related to the length of the control message;
Information related to the version of the control message;
Including extended information including configuration information associated with the table contained in the control message payload,
The table contains an asset list associated with the package,
The multimedia content receiving apparatus, wherein the specific information includes information related to the package configuration. The table, the multimedia content receiving apparatus according to claim 1, characterized in that it comprises a table identifier identifying the table.

Images