JP2023082691A - Transmission device, reception device, and program - Google Patents

Abstract

To transmit an arbitrary file with low delay, in a broadcast transmission line.SOLUTION: A transmission device 10 comprises: a package constitution part 11 which constitutes a package in which a predetermined file is stored in a data region of a general-purpose data asset and information on the file is stored in an MP table or a general-purpose data header region; and a transmission part 12 which transmits the package constituted by the package constitution part 11, via the broadcast transmission line.SELECTED DRAWING: Figure 2

Description

The present invention relates to a transmitting device, a receiving device and a program.

In the Advanced Terrestrial Broadcasting System, program content transmitted in a common media format is centrally managed by the receiving system, regardless of the transmission path such as broadcasting or communication, and is managed by the Web browser installed in various viewing terminals. The introduction of a uniform viewing mechanism is under consideration.

Streaming distribution using HTTP (Hyper Text Transfer Protocol) (see Non-Patent Document 1) is assumed as a mechanism for uniformly viewing program content on a Web browser. In order to enable viewing of program content on a Web browser, a segment file obtained by dividing the program content at regular time intervals and a manifest file (non-patent document 2) must be prepared in the receiving system.

RFC8216, “HTTP Live Streaming”, [Searched on November 15, 2021], Internet <URL: https://tools.ietf.org/html/rfc8216> ISO/IEC 23009-1, “Information Technology - Dynamic Adaptive Streaming over HTTP (DASH) - Part 1: Media Presentation Description and Segment Formats”

2. Description of the Related Art In a broadcasting system, program content is transmitted by so-called broadcast transmission, in which the same content is simultaneously transmitted to a plurality of receiving terminals. Since the program control information describing the content structure is transmitted at short fixed time intervals, the receiving terminal receives the program control information and immediately acquires the content structure at an arbitrary viewing start timing, thereby enabling the program content to be displayed. You can start watching.

On the other hand, in streaming distribution using HTTP, a manifest file is distributed according to a request from each receiving terminal. You can start watching content.

In the new broadcasting system based on the advanced terrestrial broadcasting method, it is necessary to provide the reception system with the information that was provided as program control information in the conventional broadcasting system as a manifest file so that the program content can be viewed. . As described above, in the new broadcasting system based on the advanced terrestrial broadcasting system, there is a demand for a method capable of transmitting arbitrary files with low delay, but this method has not been sufficiently studied.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a transmitting device, a receiving device, and a program capable of transmitting any file with low delay in a broadcasting system.

(1) A transmission device according to the present invention is a transmission device for transmitting a package corresponding to program content by a general-purpose data transmission method, wherein the package includes at least one asset for transmitting data of the program content; and a control message, wherein the control message includes an MP table including reference information for referring to the asset, and the asset includes a data area in which general-purpose data is stored and information on the general-purpose data. a general-purpose data header area including a general-purpose data asset, wherein a predetermined file is stored in the data area of the general-purpose data asset, and information about the file is stored in the MP table or the general-purpose data header area; A package configuration unit that configures a package, and a transmission unit that transmits the package configured by the package configuration unit via a broadcast transmission line.

(2) In the transmitting device according to (1), the reference information corresponding to the general-purpose data asset includes an MH-data encoding scheme descriptor describing information on a data encoding scheme, and the MH-data The encoding scheme descriptor includes additional_data_component_info, and the package configuration unit stores information about the file in the additional_data_component_info.

(3) In the transmission device according to (2), the package configuration unit includes, as information about the file, an ID assigned to the file, a version of the file, a file name of the file, a MIME type of the file, and Information about the compression format of the file is stored in the additional_data_component_info.

(4) In the transmission device according to (1), when storing the information about the file in the general-purpose data header area, the package configuration unit stores the name of the file and the compression format of the file as the information about the file. is stored in the general-purpose data header area.

(5) In the transmitting device according to (4), the reference information corresponding to the general-purpose data asset includes an MPU timestamp descriptor that describes information about the presentation time of the MPU that constitutes the general-purpose data asset, The MPU timestamp descriptor includes mpu_presentation_time and mpu_sequence_number, and the package component uses the value of mpu_presentation_time as information about the version of the file.

(6) In the transmission device according to (4), the general-purpose data header area of the general-purpose data asset includes mpu_presentation_time, and the package configuration unit uses the value of mpu_presentation_time as information about the version of the file. use.

(7) In the transmitting device according to any one of (2) to (6), the package configuration unit stores flag information indicating whether or not information about the file is stored in the additional_data_component_info. Include in additional_data_component_info.

(8) In the transmission device according to any one of (1) to (7), the file is a file referenced for viewing the program content.

(9) A receiving device according to the present invention is a receiving device that receives the package transmitted from the transmitting device according to any one of (1) to (8), wherein the MP table of the received package or A demultiplexing unit that refers to information about the file stored in the general-purpose data header area and obtains the predetermined file stored in the data area of the general-purpose data asset.

(10) A program according to the present invention causes a computer to function as the transmission device according to any one of (1) to (8).

(11) A program according to the present invention causes a computer to function as the receiving device according to (9).

According to the transmitting device, receiving device, and program according to the present invention, it is possible to transmit any file with low delay in a broadcasting system.

1 is a diagram showing a configuration example of a transmission/reception system including a transmission device according to an embodiment of the present invention; FIG. 2 is a diagram showing a configuration example of a transmission device shown in FIG. 1; FIG. FIG. 4 is a diagram showing a configuration example of a package in asynchronous general-purpose data transmission; FIG. 13 is a diagram illustrating a configuration example of additional_data_component_info; It is a figure which shows the example of a setting of compression_type. FIG. 13 is a diagram illustrating a configuration example of additional_info; FIG. 4 is a diagram showing a configuration example of a package in synchronous general-purpose data transmission; FIG. 11 is a diagram showing another configuration example of additional_info;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration example of a transmitting/receiving system 1 as a broadcasting system including a transmitting device 10 according to one embodiment of the present invention.

As shown in FIG. 1, the transmission/reception system 1 includes a transmission device 10 and a reception system 20 according to this embodiment.

The transmitting device 10 transmits program content via an arbitrary transmission path such as a broadcast transmission path or a communication transmission path via a communication line. Specifically, the transmitting device 10 multiplexes and transmits a video/audio stream of program content, program control information describing the content configuration, a manifest file, and the like. The transmission device 10 transmits program content by, for example, broadcast transmission via a broadcast transmission line. Also, the transmitting device 10 transmits program content via a communication transmission line in response to a request from an individual receiving system 20, for example. A manifest file is a file that describes attributes, URLs, etc. of segment files, and is a file that is referred to for viewing program content in the receiving system 20 . An example in which the transmitting device 10 transmits a manifest file to the receiving system 20 will be described below, but the present invention is not limited to this, and the transmitting device 10 can transmit any file.

A receiving system 20 as a receiving device receives and presents program content transmitted by the transmitting device 10 . The reception system 20 includes a communication section 21 and a presentation section 22 . The communication unit 21 and the presentation unit 22 may be provided as one device. Also, the communication unit 21 and the presentation unit 22 may be provided as separate devices. In this case, the communication unit 21 is, for example, a router having a broadcast reception function, and the presentation unit 22 is, for example, various terminals (smartphone, tablet, etc.) capable of presenting program content to the user.

The communication unit 21 includes a demultiplexing unit 211 , an HTTP client 212 , a storage unit 213 and a web server 214 .

The demultiplexing unit 211 receives broadcast waves transmitted from the transmission device 10 via the broadcast transmission path, and demultiplexes the multiplexed video/audio stream, program control information and manifest file. Based on the received program control information, the demultiplexing unit 211 generates segment files by dividing the video/audio stream at regular time intervals, and outputs the generated segment files and manifest files to the storage unit 213 .

The HTTP client 212 acquires the segment file obtained by referring to the manifest file and the acquired manifest file from the server on the communication transmission line. The HTTP client 212 outputs the acquired segment file and manifest file to the storage unit 213 .

Storage unit 213 stores the segment file and manifest file output from demultiplexing unit 211 or HTTP client 212 .

The Web server 214 transmits the manifest file and the segment file in response to a request from the presentation unit 22, for example, by communicating with the presentation unit 22 using HTTP.

The presentation unit 22 includes a web browser 221 capable of communicating with the communication unit 21 (web server 214) using HTTP, and receives manifest files and segment files from the web server 214 via the web browser 221. . The web browser 221 refers to the received manifest file, sequentially decodes the segment files, and presents the program content.

Next, the configuration of the transmission device 10 according to this embodiment will be described with reference to FIG.

In the present embodiment, the transmission device 10 transmits program content via a broadcast transmission path by a general-purpose data transmission method defined in the following references. The general-purpose data transmission method is a method for transmitting various data in a synchronous or asynchronous manner, and is used in receiving terminals that present data other than video, audio, and subtitles, or in multimedia services. This method is suitable for transmitting arbitrary data such as data. Further, in this embodiment, the transmission device 10 multiplexes and transmits a video stream, an audio stream, etc. of program content using MMT (MPEG Media Transport) defined in the reference below. In MMT, the unit of program content is defined as a "package", and the transmitting device 10 transmits a package corresponding to program content using a general-purpose data transmission method.
<References>
ARIB STD-B60, "Media transport method by MMT in digital broadcasting"

As shown in FIG. 2 , the transmitting device 10 according to this embodiment includes a package forming section 11 and a transmitting section 12 .

The package construction unit 11 constructs a package in which the video and audio stream of the program content and the manifest file, which is a file referred to for viewing the program content, are multiplexed, and outputs the package to the transmission unit 12 . The details of the configuration of the package by the package configuration unit 11 will be described later.

The transmission unit 12 transmits the package configured by the package configuration unit 11 via an arbitrary transmission line such as a broadcast transmission line and a communication transmission line.

FIG. 3 is a diagram showing a configuration example of a package in the asynchronous general-purpose data transmission system. The asynchronous general-purpose data transmission system is a system used when timing synchronization between video/audio data and other data is unnecessary.

In MMT, components such as video data and audio data of program content (elements constituting program content) are defined as assets. An asset is a structure in which MPUs (Media Processing Units) are continuous. The MPU is a data processing unit in MMT. That is, an MPU is a unit that includes data used at a certain timing and can perform video and audio decoding processing by itself. The MPU includes at least one MFU (Media Fragment Unit). The MFU includes a header area and a data area. Program content is defined as a package that includes one or more assets that carry program content data and control messages.

The package configuration unit 11 includes a video data asset (not shown in FIG. 3) in which video data of program content is stored in the MPU, and an audio data asset (not shown in FIG. 3) in which audio data of the program content is stored in the MPU. ).

As described above, the general-purpose data transmission method is a method suitable for transmitting various data other than video, audio, and subtitles (hereinafter referred to as "general-purpose data"). The assets that make up the package include generic data assets for transmitting generic data. A general-purpose data asset is composed of consecutive MPUs, as shown in FIG. The MPU also includes at least one MFU consisting of a general-purpose data header area and a data area in which general-purpose data is stored.

The package construction unit 11 stores the manifest file in the data area of the general-purpose data asset. As described above, in this embodiment, by using the general-purpose data transmission method and storing the manifest file in the data area of the general-purpose data asset, the manifest file can be transmitted with low delay. Note that the package configuration unit 11 may compress and multiplex a series of manifest file sets and store them in the data area of the general-purpose data asset.

As mentioned above, the package contains control messages. The control message includes an MP (MMT Package) table as shown in FIG. The MP table contains reference information for referencing the assets included in the package.

Specifically, the MP table includes reference information (asset ID and location information) for referencing video assets and reference information (asset ID and location information) for referencing audio assets. The MP table also contains reference information for referencing generic data assets. Reference information for generic data assets includes asset ID, asset type, location information, and the like. As the asset type, "aagd" is input to indicate that the general-purpose data stored in the data area of the corresponding general-purpose data asset is asynchronous general-purpose data.

The generic data asset reference information further includes an MH-Data Encoding Descriptor that describes information about the data encoding. The MH-Data Coding Scheme Descriptor includes data_component_id and additional_data_component_info. data_component_id indicates the encoding method of general-purpose data stored in the data area of the general-purpose data asset. Additional_data_component_info stores additional identification information defined for each data encoding method.

The package configuration unit 11 may store information about the file (manifest file) stored in the data area of the general-purpose data asset in, for example, additional_data_component_info.

FIG. 4 is a diagram showing a configuration example of additional_data_component_info.

As shown in FIG. 4, additional_data_component_info includes target_path, file_id, file_version, file_name, data_type and compression_type. target_path is a character string indicating a common part of folders storing files to be transmitted. file_id indicates a unique ID assigned to the file to be transmitted. file_id is associated with the upper 16 bits of the sequence number of the MPU that transmits the file. file_version indicates the version of the file to be transmitted, and is incremented when the file is updated. file_version is associated with the lower 16 bits of the sequence number of the MPU that transmits the file. file_name indicates the file name of the file to be transmitted. data_type indicates the MIME (Multipurpose Internet Mail Extensions) type of the file to be transmitted. compression_type indicates the compression format of the file to be transmitted. Compression_type is set to a value (Compression Type ID) corresponding to the compression format of the file to be transmitted, as shown in FIG.

The package configuration unit 11 stores information corresponding to the manifest file in each item of the above-described additional_data_component_info as information about the manifest file. Also, when storing information about the manifest file in additional_data_component_info, the package configuration unit 11 sets the file_info_flag of additional_data_component_info to “1”. In this way, the package configuration unit 11 includes flag information (file_info_flag) indicating whether or not information about a file is stored in additional_data_component_info in additional_data_component_info.

When the file_info_flag of additional_data_component_info is set to "1", the receiving system 20 as a receiving device refers to the above-described information about the segment file included in the additional_data_component_info to obtain the manifest file transmitted as the general-purpose data asset. can be obtained.

Referring to FIG. 3 again, the package configuration unit 11 may store information about the manifest file in the generic data header area of the generic data asset instead of additional_data_component_info.

The general data header area includes component_tag, data_type, additional_info, and data_length. component_tag is a tag that identifies a component. data_type indicates the MIME type of data stored in the data area and transmitted. additional_info is additional information of data stored in the data area and transmitted. data_length indicates the data length of data stored in the data area and transmitted.

The package configuration unit 11 may store information about the file (manifest file) stored in the data area of the general-purpose data asset in additional_info of the general-purpose data header area.

FIG. 6 is a diagram showing a configuration example of additional_info.

As shown in FIG. 6, the package configuration unit 11 includes file_name and compression_type in additional_info as information about the manifest file. That is, when storing information about the manifest file in the general-purpose data header area, the package configuration unit 11 stores information about the name of the file (file_name) and the compression format of the file (compression_type) in the general-purpose data header area.

Note that when information about the manifest file is stored in additional_info in the general-purpose data header area, the package configuration unit 11 does not need to store target_path, file_id, file_version, and data_type in additional_data_component_info. This information is unnecessary because the manifest file is stored in the data area that constitutes the MFU together with the general-purpose data header area.

When storing information about the manifest file in additional_info of the general-purpose data header area, the package configuration unit 11 describes only target_path in additional_data_component_info and sets "0" in file_info_flag.

By storing information about the manifest file in additional_info in the general data header area, the data size of the MH-data encoding method descriptor can be minimized.

The package forming unit 11 forms a package by multiplexing the above-described video assets, audio assets, general-purpose data assets, control messages (MP tables), and the like. Here, the package construction unit 11 constructs a package in which the manifest file is stored in the data area of the general-purpose data asset, and information about the file is stored in the MP table or the general-purpose data header area.

As described with reference to FIG. 1, the reception system 20 as a reception device includes the demultiplexer 211 . The demultiplexing unit 211 can refer to the MP table of the received package or the information related to the files stored in the general data header area, and acquire a predetermined file stored in the data area of the general data asset. .

As described above, the general-purpose data transmission scheme allows arbitrary data to be stored in the data area of the general-purpose data asset and transmitted with low delay. Therefore, according to this embodiment, the package configuration unit 11 stores not only the manifest file but also any file in the data area of the general-purpose data asset, and stores the information about the file stored in the data area in the MP table or the general-purpose data It can be stored and transmitted in the general data header area of the asset. Therefore, according to the transmission device 10 according to the present embodiment, it is possible to transmit any file with low delay on the broadcast transmission path.

So far, an example has been described in which the transmitting device 10 transmits program content by asynchronous general-purpose data transmission, but the present disclosure is not limited to this, and the transmitting device 10 transmits program Content may be transmitted.

In the case of the synchronous general-purpose data transmission method, as shown in FIG. 7, the asset type included in the reference information of the general-purpose data asset is "asgd" indicating that the data transmitted by the general-purpose data asset is synchronous data. is set.

The generic data asset reference information further includes an MPU timestamp descriptor that describes information about the presentation time of the MPUs that compose the generic data asset. As shown in FIG. 7, the MPU timestamp descriptor includes mpu_sequence_number and mpu_presentation_time. mpu_sequence_number indicates the sequence number of the MPU describing the timestamp. mpu_presentation_time indicates the presentation time of the MPU.

When storing file_name and compression_type as information about the manifest file in additional_info of the general-purpose data header area, the package configuration unit 11 uses the value of mpu_presentation_time of the MPU time stamp descriptor as information about the version of the manifest file. good. That is, the package configuration unit 11 may use the value of mpu_presentation_time as information about the version of the file. In this case, the receiving system 20 can recognize that the file transmitted by the general-purpose data asset has been updated by updating the value of mpu_presentation_time of the MPU timestamp descriptor.

Also, the package configuration unit 11 may store information about the version of the manifest file in additional_info included in the general-purpose data header area instead of the MPU timestamp descriptor. That is, as shown in FIG. 8, the package configuration unit 11 may add mpu_presentation_time to additional_info and use the value of mpu_presentation_time to store information about the version of the manifest file.

As described above, the transmission device 10 according to the present embodiment stores a predetermined file in the data area of the general-purpose data asset, and stores information about the file in the MP table or the general-purpose data header area. 11, and a transmission unit 12 that transmits the package configured by the package configuration unit 11 via a broadcast transmission line.

In addition, the receiving system 20 as a receiving device according to the present embodiment refers to the information about the file stored in the MP table or the general data header area of the received package, and refers to the information stored in the data area of the general data asset. A demultiplexing unit 211 is provided for obtaining a predetermined file from the

By using a general-purpose data transmission method that can transmit arbitrary files, arbitrary files are stored in the data area of the general-purpose data asset, and information about the file is stored in the MP table or general-purpose data header area and transmitted. Any file can be transmitted with low delay on the road. In particular, if the file is a manifest file that is referred to for viewing program content, the program content can be viewed in the receiving system 20 by transmitting the manifest file and information about the manifest file through the broadcast transmission path. Become.

Although not particularly mentioned in the embodiment, a program may be provided that causes a computer to function as the transmitting device 10 or the receiving system 20 as the receiving device. Also, the program may be recorded on a computer-readable medium. It can be installed on a computer using a computer readable medium. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, but may be, for example, a recording medium such as a CD-ROM or a DVD-ROM.

Alternatively, the transmitting device 10 or the receiving system 20 as the transmitting device 10 or the receiving device is composed of a memory storing a program for executing each process and a processor executing the program stored in the memory, and the transmitting device 10 or the receiving device A chip mounted in the receiving system 20 as a may be provided.

Although the above embodiments have been described as representative examples, it will be apparent to those skilled in the art that many modifications and substitutions are possible within the spirit and scope of the invention. Therefore, this invention should not be construed as limited by the above-described embodiments, and various modifications and changes are possible without departing from the scope of the claims. For example, it is possible to combine a plurality of configuration blocks described in the configuration diagrams of the embodiments into one, or divide one configuration block.

Reference Signs List 1 transmission/reception system 10 transmission device 11 package component 12 transmission unit 20 reception system (reception device)
21 communication unit 22 presentation unit 211 demultiplexing unit 212 HTTP client 213 storage unit 214 web server 221 web browser

Claims (11)

A transmitting device that transmits a package corresponding to program content by a general-purpose data transmission method,
the package includes at least one asset carrying data of the program content and a control message;
the control message includes an MP table including reference information for referencing the asset;
The asset includes a general-purpose data asset including a data area storing general-purpose data and a general-purpose data header area containing information about the general-purpose data,
a package configuration unit that configures the package, storing a predetermined file in the data area of the general-purpose data asset, and storing information about the file in the MP table or the general-purpose data header area;
and a transmission unit configured to transmit the package configured by the package configuration unit via a broadcast transmission line. The transmitting device according to claim 1,
the reference information corresponding to the generic data asset includes an MH-Data Encoding Descriptor that describes information about a data encoding;
the MH-data encoding scheme descriptor includes additional_data_component_info;
The transmission device, wherein the package configuration unit stores information about the file in the additional_data_component_info. The transmitting device according to claim 2,
The package configuration unit stores, as information about the file, information about the ID assigned to the file, the version of the file, the file name of the file, the MIME type of the file, and the compression format of the file in the additional_data_component_info. , transmitter. The transmitting device according to claim 1,
When storing information about the file in the general-purpose data header area, the package configuration unit stores information about the name of the file and information about the compression format of the file in the general-purpose data header area as the information about the file. Device. The transmitting device according to claim 4,
The reference information corresponding to the generic data asset includes an MPU timestamp descriptor that describes information about the presentation time of the MPUs that make up the generic data asset;
the MPU timestamp descriptor includes mpu_presentation_time and mpu_sequence_number;
The sending device, wherein the package configuration unit uses the value of the mpu_presentation_time as information about the version of the file. The transmitting device according to claim 4,
the generic data header field of the generic data asset includes mpu_presentation_time;
The sending device, wherein the package configuration unit uses the value of the mpu_presentation_time as information about the version of the file. In the transmitting device according to any one of claims 2 to 6,
The transmitting device, wherein the package configuration unit includes in the additional_data_component_info flag information indicating whether or not the information about the file is stored in the additional_data_component_info. In the transmitting device according to any one of claims 1 to 6,
The transmission device, wherein the file is a file referenced for viewing the program content. A receiving device for receiving the package transmitted from the transmitting device according to any one of claims 1 to 6,
Demultiplexing for obtaining the predetermined file stored in the data area of the general-purpose data asset by referring to the information about the file stored in the MP table or the general-purpose data header area of the received package. a receiver, comprising: A program that causes a computer to function as the transmission device according to any one of claims 1 to 6. A program that causes a computer to function as the receiving device according to claim 9 .

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