JP2019062547A - Control message generation device, distribution system, receiving device, and programs for them - Google Patents

Abstract

To provide a control message generation device capable of suppressing an expected value of a hop number required to when reception becomes possible.SOLUTION: A control message generation device comprises: a table generation part that generates a first table including reference information to each of assets configuring a first package, and a second table including reference information to each of assets configuring a second package; a package list table generation part that generates a package list table including reference information to the second table; and a control message generation part that generates a first control message including the first table and the package list table, and a second control message including the second table.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a control message generator, a distribution system, a receiver, and their programs.

  In current digital television broadcasting such as terrestrial digital television broadcasting, MPEG (Moving Picture Experts Group) 2-TS (Transport Stream) standardized as ISO / IEC 13818-1 is used. In these digital television broadcasts, in addition to video and audio streams, tables called Program Association Table (PAT) and Program Map Table (PMT) are periodically transmitted (for example, Non-Patent Document 1) , 2).

  The PMT is a table prepared for each program, and stores a video stream constituting the program and a PID which is reference information to an audio stream. The PAT is a table prepared only once in the MPEG2-TS, and stores PIDs which are reference information to each PMT transmitted by the MPEG2-TS.

  When receiving a certain program, a receiving apparatus that receives digital television broadcasts first obtains PAT from MPEG2-TS. Referring to this PAT, since the PID of the PMT of the program to be received can be known, the receiving apparatus acquires the PMT of the program to be received from the MPEG2-TS. Then, referring to this PMT, the PID of the video and audio stream of the program to be received can be known, so the receiving apparatus acquires the video and audio stream of the program to be received from the MPEG2-TS, and displays the video and audio. Output.

ARIB STD-B32 2.8 Edition, Radio Wave Industry Association, December 18, 2012 "Video Coding, Audio Coding and Multiplexing in Digital Broadcasting" "Program arrangement information used for digital broadcasting", ARIB STD-B10 4.8 edition, Japan Radio Industry Association, April 26, 2010

  However, in a system using MPEG2-TS, such as the above-mentioned digital television broadcasting, as described above, the PAT can be received until the receiving apparatus can receive the video and audio streams constituting the program. There is a problem that two hops of obtaining PMT are always required. Since two hops are required, the expected value of the time taken to receive the video or audio stream after the program to be received is specified is the period during which PAT is being transmitted and the period during which PMT is being transmitted. It will be the sum of Therefore, when trying to shorten the time, the transmission cycle of PAT and PMT will be shortened, and the video and audio bandwidth will be compressed. Also, if you try to reduce the pressure on the video and audio bands, you will increase the PAT or PMT transmission cycle, and it will take from the time the program to be received is specified to the time the video and audio streams are received. Will be longer.

  The present invention has been made in view of such circumstances, and provides a control message generation device, a distribution system, a reception device, and a program capable of suppressing an expected value of the number of hops until reception becomes possible.

(1) The present invention has been made to solve the above-described problems, and one aspect of the present invention is to provide a first table including reference information to each of the assets constituting the first package, and a second table. A table generation unit for generating a second table including reference information to each of assets constituting the package; a package list table generation unit for generating a package list table including reference information to the second table; Control message generation characterized by comprising a control message generation unit generating a first control message including a first table and the package list table, and a second control message including the second table. It is an apparatus.

(2) Further, another aspect of the present invention is the control message generating device according to (1), wherein the reference information to the second table includes the second table. It is characterized in that it is the packet ID of the packet storing the message.

(3) In addition, another aspect of the present invention includes a first table including reference information to each of the assets constituting the first package, and a reference information to each of the assets constituting the second package. A control message generator for generating a first control message including a package list table including reference information to two tables and a second control message including the second table; and the first control message And a distribution apparatus that distributes the second control message using a data flow.

(4) Also, another aspect of the present invention is the second aspect of the present invention, comprising: a first table including reference information to each of the assets constituting the first package; A receiver that receives a data flow including a first control message including a package list table including reference information to a table of the second table and a second control message including the second table, the desired package A designated acquisition unit for acquiring information designated, a reception unit for receiving the data flow, a separation unit for separating the first control message from the data flow, and the first control message included in the first control message Referring to Table 1, when the first package matches the desired package, the separation of the first package is fingered to the separation section. A receiving apparatus characterized by comprising a control message processor for.

(5) Further, another aspect of the present invention is the receiving device according to (4), wherein the control message processing unit refers to the first table included in the first control message. If the first package does not match the desired package, the second table corresponding to the desired package is referred to by referring to the package list table included in the first control message. The reference information is acquired, and using the acquired reference information, the separation unit is instructed to separate the second control message including the second table corresponding to the desired package.

(6) In addition, another aspect of the present invention relates to a computer including: a first table including reference information to each of assets making up the first package; and reference information to each of assets making up the second package A table generation unit for generating a second table including the package list; a package list table generation unit for generating a package list table including reference information to the second table; a first table including the first table and the package list table; The program is configured to function as a control message generation unit that generates one control message and a second control message including the second table.

(7) In addition, another aspect of the present invention includes the first table including reference information to each of the assets constituting the first package, and the second table including reference information to each of the assets constituting the second package. A computer of a receiving device receiving a data flow including a first control message including a package list table including reference information to a table of the second table and a second control message including the second table; A designation acquisition unit for acquiring information designating the reception unit, a reception unit for receiving the data flow, a separation unit for separating the first control message from the data flow, the first table included in the first control message And, when the first package matches the desired package, the separation of the first package is fingered to the separation section. Is a program for functioning as a control message processor for.

  According to the present invention, the expected value of the number of hops until reception becomes possible can be suppressed.

It is a schematic block diagram showing composition of distribution system 10 by one embodiment of this invention. It is a schematic block diagram which shows the structure of the control message production | generation apparatus 11 in the embodiment. It is a schematic block diagram which shows the structure of the receiver 17 in the embodiment. It is a conceptual diagram which shows the structure of the IP data flow which the delivery apparatus 16 in the embodiment distributes. It is a table showing the data structure of the PA message in the same embodiment. It is a table (the 1) which shows the data structure of MP table in the embodiment. It is a table (the 2) which shows the data structure of MP table in the embodiment. It is a table (the 3) which shows the data structure of MP table in the embodiment. It is a table (the 1) which shows the data structure of the reference information in the embodiment. It is a table (the 2) showing the data structure of the reference information in the embodiment. It is a table (the 3) showing the data structure of the reference information in the embodiment. It is a table (the 1) showing the data structure of the package list table in the embodiment. It is a table (the 2) which shows the data structure of the package list table in the embodiment. It is a flowchart explaining operation | movement of the designation | designated acquisition part 72 in the same embodiment, the receiving control part 73, and the control message processing part 74. FIG. It is a conceptual diagram which shows the structure of the IP data flow which the delivery apparatus 16 in the modification 1 of the embodiment delivers. It is a table (the 1) showing the data structure of MP table in modification 2 of the embodiment. It is a table (the 2) which shows the data structure of MP table in modification 2 of the embodiment. It is a table (the 3) which shows the data structure of MP table in modification 2 of the embodiment. It is a table (the 1) showing the data structure of the reference information in modification 2 of the embodiment. It is a table (the 2) which shows the data structure of the reference information in the modification 2 of the embodiment. It is a table (the 1) showing the data structure of the package list table in modification 2 of the embodiment. It is a table (the 2) showing the data structure of the package list table in modification 2 of the embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram showing the configuration of a distribution system 10 according to an embodiment of the present invention. The distribution system 10 includes a control message generation device 11, a plurality of video transmission devices 12, a plurality of audio transmission devices 13, a plurality of data transmission devices 14, a multiplexing device 15, a distribution device 16, a reception device 17, and an output device 18. Configured The delivery system 10 delivers the content to the receiving device 17 using the IP data flow. The IP data flow is, for example, a flow of multicast using UDP / IP, and is determined by the IP address of the transmission source, the IP address of the destination, and the port number of the destination. Also, the IP data flow may be transmitted by a bidirectional transmission path such as the Internet, or may be transmitted by a unidirectional transmission path such as terrestrial digital broadcasting or satellite digital broadcasting.

  The control message generator 11 generates a control message (Signaling Message) of MMT (MPEG Media Transport), and inputs it to the multiplexer 15. In the present embodiment, the control message generated by the control message generator 11 is a PA message (Package Access message) including an MP table (MMT Package table), a package list table, and a PA message including only the MP table. . The MP table stores the package ID of the target package and reference information (MMT_general_location_info) to the assets constituting the package. The package list table stores reference information (such as packet ID) to the MP table of each package included in the data flow transmitting the package list table. In the present embodiment, the package list table does not include reference information to the MP table included in the PA message together with the package list table, but may include it.

  The PA message is a type of control message (Signaling Message) in the MMT. An asset is media such as a video stream, an audio stream, a data stream, a hypertext file, and an image file. A package is a collection of one or more assets that make up content. For example, the assets constituting a certain movie package are a video stream, an audio stream, and a subtitle data stream. When the video stream includes low-resolution ones for mobile and high-resolution ones for stationary, the package includes both. Note that a part of the assets constituting the package may be distributed from a device different from the distribution device 16 using a transmission path different from the transmission path between the distribution device 16 and the reception device 17. The details of the MP table, the package list table, and the PA message will be described later.

  The video transmission device 12 generates a video stream among the assets constituting the content, and inputs the video stream to the multiplexing device 15. The audio transmission device 13 generates a stream of audio among the assets constituting the content, and inputs the stream to the multiplexing device 15. The data transmission device 14 generates a stream of data among the assets constituting the content and inputs the stream to the multiplexing device 15. The stream of data is, for example, information displayed accompanying the video, subtitles superimposed on the video, and the like.

  The multiplexer 15 stores the input control message, the video stream, the audio stream, and the data stream in MMT packets, arranges the MMT packets in time series, and multiplexes the MMT packets. The multiplexer 15 sets the packet ID of the MMT packet to a value set in advance for each stored stream or control message. In particular, the multiplexer 15 sets “0” as the packet ID of the MMT packet in which the PA message storing both the MP table and the package list table is stored. The distribution apparatus 16 stores the MMT packet multiplexed by the multiplexing apparatus 15 in an IP packet to generate and distribute an IP data flow.

  The receiving device 17 receives the IP data flow distributed by the distribution device 16. The receiving device 17 generates a decoded signal of the content included in the received IP data flow, and inputs it to the output device 18. The output device 18 includes, for example, a liquid crystal display and a speaker, displays an image represented by the input decoded signal on the liquid crystal display, and outputs an audio represented by the decoded signal from the speaker.

  FIG. 2 is a schematic block diagram showing the configuration of the control message generator 11. As shown in FIG. The control message generator 11 includes an MP table generator 21, a package list table generator 22, and a PA message generator 23. The MP table generation unit 21 generates an MP table of each package transmitted by the distribution device 16. The package list table generation unit 22 generates a package list table including a package ID corresponding to each MP table generated by the MP table generation unit 21 and a packet ID of an MMT packet storing the MP table. The package list table may not include the package ID of the MP table stored in the same PA message as the package list table and the packet ID.

  The PA message generator 23 (control message generator) generates a PA message storing the MP table generated by the MP table generator 21. However, in the PA message storing the specific MP table, the PA message generation unit 23 also stores the package list table generated by the package list table generation unit 22. The PA message generator 23 inputs the generated PA message to the multiplexer 15.

  FIG. 3 is a schematic block diagram showing the configuration of the receiving device 17. As shown in FIG. The reception device 17 includes a reception unit 70, a separation unit 71, a designation acquisition unit 72, a reception control unit 73, a control message processing unit 74, a video decoding unit 75, an audio decoding unit 76, a data rendering unit 77, a video combining unit 78, and audio. The configuration includes a combining unit 79.

  The receiving unit 70 receives the IP data flow distributed by the distribution device 16 in accordance with the instruction from the reception control determining unit 73. The separation unit 71 separates the PA message included in the MMT packet whose packet ID is “0” from the IP data flow received by the reception unit 70, and inputs the PA message to the control message processing unit 74. Further, the separation unit 71 separates the control message specified by the control message processing unit 74, the video stream, the audio stream, and the data stream from the IP data flow received by the reception unit 70. The separation unit 71 inputs the separated control message to the control message processing unit 74. The separating unit 71 inputs the separated video stream to the video decoding unit 75, and inputs the separated audio stream to the audio decoding unit 76. The separation unit 71 inputs the separated data stream to the data rendering unit 77.

  The designation acquisition unit 72 acquires designation of the service to be received, which is input by the user using an input device such as a remote controller. The designation of the service is performed, for example, by the user inputting a service ID (service identifier). The reception control unit 73 instructs the reception unit 70 to receive the IP data flow transmitting the service acquired by the designation acquisition unit 72. Further, the reception control unit 73 notifies the control message processing unit 74 of the package ID of the service acquired by the designation acquisition unit 72. For example, the lower 16 bits of the package ID match the service ID.

  The control message processing unit 74 acquires the MP table of the package ID notified from the reception control unit 73 from the control message separated by the separation unit 71. The control message processing unit 74 determines the video stream, the audio stream, and the data stream to be reproduced with reference to the acquired MP table, and designates the determined stream to the separation unit 71. Details of the method for acquiring the MP table of the package ID notified from the reception control unit 73 will be described later.

  The video decoding unit 75 decodes the video stream input from the separation unit 71 and generates a video signal. The audio decoding unit 76 decodes the audio stream input from the separating unit 71 and generates an audio signal. The data rendering unit 77 renders the data stream input from the separating unit 71 to generate a video signal and an audio signal. In addition, the data rendering unit 77 also generates a signal designating a method of combining the generated video signal and the video signal generated by the video decoding unit 75 by rendering a data stream.

  For example, if the data stream is a subtitle data stream, the synthesizing method designated by the signal generated by the data rendering unit 77 is the video generated by the data rendering unit 77 in the video represented by the video signal generated by the video decoding unit 75 It is a method of superimposing subtitles represented by a signal. Also, if the data stream is to display information on the outer left side and the lower outer side of the video represented by the video signal generated by the video decoding unit 75, the synthesizing method designated by the signal generated by the data rendering unit 77 is The video represented by the video signal generated by the video decoding unit 75 is reduced, and the video represented by the video signal generated by the data rendering unit 77 is arranged on the outer left and lower outer sides of the reduced video.

  The video synthesizing unit 78 synthesizes the video signal generated by the video decoding unit 75 and the video signal generated by the data rendering unit 77 in accordance with the signal specifying the synthesizing method generated by the data rendering unit 77, and outputs the output device 18 Generate a video signal of the video to be displayed on the The voice synthesis unit 79 superimposes the voice signal generated by the voice decoding unit 76 and the voice signal generated by the data rendering unit 77 to generate a voice signal of voice to be output to the output device 18.

  FIG. 4 is a conceptual diagram showing the configuration of the IP data flow distributed by the distribution device 16. In the example shown in FIG. 4, a plurality of packages are transmitted by one IP data flow DF. For example, the IP data flow DF is transmitted by a TLV (Type Length Value) stream if the transmission medium is a broadcast wave, and is transmitted by an IP packet if the transmission medium is a LAN (Local Area Network).

  The IP data flow DF includes PA messages PA1 and PA2, video streams V1 and V2, audio streams A1 and A2, and data streams D1 and D2. Among these, the video stream V1, the audio stream A1, and the data stream D1 constitute a first package. Further, a second package is configured by the video stream V2, the audio stream A2, and the data stream D2.

  The PA message PA1 stores an MP table MP1 of the first package and a package list table PL1. The MP table MP1 stores the package ID of the first package, and the packet ID of the MMT packet for transmitting each of the video stream V1, the audio stream A1, and the data stream D1 which are assets constituting the package.

  The package list table PL1 is a packet ID of an MMT packet for transmitting each PA message (for example, PA message PA2) storing the MP table (for example, MP table MP2) of the package transmitted by the IP data flow DF. Is stored. Then, each of the MP tables (for example, MP table MP2) of the second and subsequent packages includes the package ID of the package and the assets (for example, video stream V2, audio stream A2, data stream D2) that configure the package. Stores the packet ID of the MMT packet that transmits the

  Since the PA message PA1 is stored in an MMT packet of a predetermined packet ID (for example, "0"), the separation unit 71 can separate from the IP data flow DF without reference information. . Since the IP data flow DF has such a configuration, when receiving the first package, the receiving device 17 extracts the PA message PA1 from the MMT packet whose packet ID is “0”, Further, by extracting the MP table MP1 from the PA message PA1, the configuration of the first package can be grasped and received.

  In addition, when receiving the second package, the receiving device 17 extracts the PA message PA1 from the MMT packet with the packet ID “0”, and further extracts the package list table PL1 from the PA message PA1. Then, the packet ID of the MMT packet storing the MP table MP2 of the package is obtained. The receiving device 17 can grasp the configuration of the second package and receive it by extracting the PA message PA2 from the MMT packet of this packet ID and further extracting the MP table MP2 from the PA message PA2. . When receiving the third and subsequent packages, the receiving device 17 can grasp and receive the configuration of the package by performing the same process as the second one.

  FIG. 5 is a table showing the data structure of the PA message. The data structure of the PA message in the present embodiment conforms to ISO / IEC 23008-1. In the table, no. Is a column indicating the serial number of the row in the table. The data structure is a field indicating the data structure of the PA message. The number of bits is a column indicating the number of bits of the data structure. The bit string notation is a field indicating the data format of the data structure of the number of bits. The bit string notation uimsbf is an abbreviation for unsigned integer most significant bit first. An unsigned integer, the most significant bit means the beginning.

  In FIG. "PA_message () {" of No. 1 is No. 1 hereafter. Up to 18 "}" represent PA data structures. No. placed at the beginning of the message. The “message_id” of 2 is a 16-bit area indicating the identifier (Identifier) of the PA message. No. 2 arranged next. The "version" of 3 is an 8-bit area indicating the version number of the PA message. No. 2 arranged next. The “length” of 4 is a 32-bit area indicating the number of bytes of the PA message after the area. Next No. “Extension {” of No. 5 is No. It is shown that up to 12 are PA message specific extensions to the data structure common to control messages. No. 2 arranged next. The “number_of_tables” of 6 is an 8-bit area indicating the number N of tables stored in the PA message.

  Next No. The “for (i = 0; i <N; i ++) {” of “7” is hereinafter referred to as “No. It indicates that up to 11 are repeated N times, that is, the number of stored tables. No. 2 arranged next. The “table_id” of 8 is an 8-bit area indicating the ID of the table stored in the PA message.

  No. 2 arranged next. “Table_version” of No. 9 is the previous No. This is an 8-bit area indicating the version number of the table indicated by the table ID of 8. No. 2 arranged next. 10 “table_length” is the previous No. This is an 8-bit area indicating the length of the table indicated by the table ID of 8. Next No. 11 "}" is No. No. 7 corresponding to “{” of No. 7). No. 12 "}" is no. Corresponds to 5 “{”.

  Next No. No. 13 "message_payload {" will be No. Up to 17 indicates that the payload of the PA message is stored. Next No. 14 “for (i = 0; i <N1; i ++) {” will be referred to as “}” hereinafter. It shows repeating up to 16 N times, that is, the number of stored tables. Next No. The fifteen “table ()” is an area for arranging a table. The arrangement order of the tables is No. It is the same as the arrangement order of "table_id" of 8. Next No. The 16 "}" are no. No. 14 corresponding to “{”. No. 17 "}" is No. No. 13 corresponding to "{". 18 "}" is No. Corresponds to 1 "{".

  6 to 8 are tables showing the data structure of the MP table. The data structure of the MP table in the present embodiment conforms to ISO / IEC 23008-1. In the table, no. Is a column indicating the serial number of the row in the table. The data structure is a field indicating the data structure of the MP table. The number of bits is a column indicating the number of bits of the data structure. The value is a column indicating the value taken by the data structure of the number of bits. The bit string notation is a field indicating the data format of the data structure of the number of bits. The bit string notation uimsbf is an abbreviation for unsigned integer most significant bit first. An unsigned integer, the most significant bit means the beginning. Also, bslbf in bit string notation is an abbreviation of bit string left bit first, and the bit string and the left bit mean the beginning.

  In FIG. "MPT () {" of 1 is referred to as "No. Up to 60 "}" represent the data structure of the MP table. No. placed at the top of the table. The “table_id” of 2 is an 8-bit area indicating the ID of the MP table. In the present embodiment, “0x40” representing Complete MPT is used as the ID of the MP table. No. 2 arranged next. The "version" of 3 is an 8-bit area indicating the version number of the MP table. No. 2 arranged next. The “length” of 4 is a 16-bit area indicating the number of bytes of the MP table after the area.

No. 2 arranged next. The "reserved" of 5 is a 6-bit reserved area.
No. 2 arranged next. The “MPT_mode” of 6 is a 2-bit area indicating the processing mode when the MP table is a subset. It conforms to the requirements of ISO / IEC 23008-1, but the detailed description is omitted. Next No. No. 7 “If (table_id == SUBSET_0_MPT_TABLE_ID) {” is “No. When the value of “table_id” of No. 2 is “SUBSET_0_MPT_TABLE_ID”, No. Indicates that up to 20 areas are placed.

  Next No. “MMT_package_id {” of No. 8 is No. It shows that up to 13 "}" is an area related to the package ID. No. 2 arranged next. “MMT_package_id_length” of 9 is an 8-bit area indicating the number of bytes N1 of the package ID. Next No. Ten “for (i = 0; i <N1; i ++) {” are referred to as “No. It shows that the area up to 12 is repeated N1 times, that is, the number of bytes of the package ID. No. 2 arranged next. 11 “MMT_package_id_byte” is an area indicating 1 byte in the package ID. Next No. No. 12 "}" is no. Corresponding to 10 "{", No. 13 "}" is No. Corresponds to 8 "{".

  Next No. 14 “MPT_descriptors {” will be referred to as “No. It is shown that up to 19 "}" is an area for a descriptor related to the MP table. No. 2 arranged next. 15. “MPT_descriptors_length” of 15 is a 16-bit area indicating the total N2 of the lengths of the disposed descriptors. Next No. 16 “for (i = 0; i <N2; i ++) {” are referred to as “No. It is shown to repeat up to 18 regions N2 times, that is, the total of the length of the descriptor. No. 2 arranged next. 17 “MPT_descriptors_byte” is an area indicating one byte in the descriptor. Next No. 18 "}" is No. Corresponding to 16 "{", No. The 19 "}" is No. No. 14 corresponding to “{”. No. 20 "}" is no. It corresponds to 7 "{".

  The No. 1 in FIG. 21 “number_of_assets” is an 8-bit area indicating the number of assets for which information is provided in the MP table. Next No. 22 “for (i = 0; i <N3; i ++) {” are referred to as “No. It shows that the area up to 59 is repeated N3 times, that is, the number of assets for which information is provided in the MP table.

  Next No. No. 23 “asset {” will be No. It shows that up to 29 "}" is an area related to asset ID. No. 2 arranged next. The "asset_id_length" of 24 is an 8-bit area indicating the number N4 of bytes of the allocated asset ID. Next No. No. 25 “for (i = 0; i <N4; i ++) {” is hereinafter referred to as “No. It shows that the area up to 27 is repeated N4 times, that is, the number of bytes of the asset ID. No. 2 arranged next. "Asset_id_byte" of 26 is an area indicating one byte in the asset ID. Next No. No. 27 "}" is no. Corresponds to 25 "{".

  No. 2 arranged next. The 28 “mime_type” is a 32-bit area indicating the Multipurpose Internet Mail Extension (MIME) type of the asset indicated by the asset ID. Next No. No. 29 "}" is No. Corresponds to 23 "{". Next No. No. 30 “If (asset_scheme_code ==“ GURL ”) {” ”corresponds to No. 30 when the value of“ asset_scheme_code ”is“ GURL ”. Indicates that up to 36 areas are placed.

No. 2 arranged next. 31 “packet_id” is GFD (General
File Delivery) This is a 32-bit area indicating the session ID. No. 2 arranged next. 32 “number_of_codepoints” is an 8-bit area indicating the number N8 of code points of the GFD session. Next No. No. 33 “for (i = 0; i <N8; i ++) {” is referred to as “No. It shows that the area up to 35 is repeated N8 times, that is, the number of code points. No. 2 arranged next. 34 "CodePoint ()" is an area indicating a code point table. Next No. No. 35 "}" is no. No. 33 corresponding to "{". The 36 "}" is No. Corresponds to 30 "{".

  No. 2 arranged next. 37 "reserved" is a 7-bit reserved area. No. 2 arranged next. The “asset_clock_relation_flag” 38 is a 1-bit area indicating whether the asset uses NTP (Network Time Protocol) as a clock reference destination. Next No. No. 39 “if (asset_clock_relation_flag == 1) {” has no. When the value of “asset_clock_relation_flag” of 38 is “1”, No. Indicates that up to 46 areas are placed.

  No. 2 arranged next. “Asset_clock_relation_id” of 40 is an 8-bit area indicating the ID of the clock to which the asset refers. The No. 1 in FIG. 41 "reserved" is a 7-bit reserved area. No. 2 arranged next. 42 “asset_timescale_flag” is a flag indicating whether “asset_timescale” is allocated.

  Next No. No. 43 “if (asset_timescale_flag == 1) {” is assigned to “No. When the value of “asset_timescale_flag” of 42 is “1”, No. Indicates that up to 45 areas are placed. No. 2 arranged next. "Asset_timescale" of 44 is a 32-bit area indicating the frequency of the clock to which the asset refers. Next No. No. 45 "}" is no. No. 43 corresponding to "{". The 46 "}" is No. It corresponds to 39 "{".

  Next No. “Asset_location {” of 47 is No. It is shown that up to 52 "}" is an area related to reference information (also referred to as location information) of the asset. No. 2 arranged next. "Location_count" of 48 is an 8-bit area indicating the number N6 of reference information regarding the asset. Next No. Forty-nine “for (i = 0; i <N6; i ++) {” are referred to as “No. It is shown that the area up to 51 is repeated N6 times, that is, the number of reference information. No. 2 arranged next. The 50 “MMT_general_location_info ()” are reference information (also referred to as location information) related to the asset. Details will be described later. Next No. No. 51 "}" is no. It corresponds to 49 "{", No. No. 52 "}" is No. It corresponds to 47 "{".

  Next No. No. 53 “asset_descriptors {” will be No. It is indicated that up to 58 "}" is a descriptor area for the asset. No. 2 arranged next. 54 “asset_descriptors_length” is a 16-bit area indicating the total N5 of descriptor lengths for the asset. Next No. No. 55 “for (i = 0; i <N5; i ++) {” is hereinafter referred to as “No. It is shown that the area up to 57 is repeated N5 times, that is, the total of the length of the descriptor. No. 2 arranged next. 56 "asset_descriptors_byte" is an area indicating one byte in the descriptor. Next No. No. 57 "}" is No. No. 55 corresponding to 55 "{". No. 58 "}" is No. It corresponds to 53 "{", No. No. 59 "}" is no. In correspondence with 22 “{”, No. 60 "}" is no. Corresponds to 1 "{".

9 to 11 are tables showing the data structure of reference information. The data structure of reference information (general_location_info) in this embodiment is ISO / IEC.
It is in accordance with 23008-1. In the table, no. Is a column indicating the serial number of the row in the table. The data structure is a field indicating the data structure of reference information. The number of bits is a column indicating the number of bits of the data structure. The value is a column indicating the value taken by the data structure of the number of bits. The bit string notation is a field indicating the data format of the data structure of the number of bits. The bit string notation uimsbf is an abbreviation for unsigned integer most significant bit first. An unsigned integer, the most significant bit means the beginning. Also, bslbf in bit string notation is an abbreviation of bit string left bit first, and the bit string and the left bit mean the beginning. Also, the bit string notation char means a character.

  In FIG. “MMT_general_location_info () {” of 1 is referred to as “No. 63 up to "}" indicate that it is a data structure of reference information. No. 2 arranged next. The “location_type” of 2 is an 8-bit area indicating the type of reference information. When “location_type” is “0x00”, it indicates that the location (data path) is the same IP data flow as the IP data flow transmitting this “location_type”. Note that 0x indicates that the subsequent character string is a hexadecimal number.

  When "location_type" is "0x01", it indicates that the location is UDP / IP (version 4). When "location_type" is "0x02", it indicates that the location is UDP / IP (version 6). When "location_type" is "0x03", it indicates that the location is an MPEG-2 TS distributed in a broadcast network. When “location_type” is “0x04”, it indicates that the location is an elementary stream in an MPEG-2 TS distributed in an IP broadcast network.

  When “location_type” is “0x05”, it indicates that the location is a URL (Uniform Resource Locator). When "location_type" is "0x06", it indicates that the location is a continuous area in the file specified by the URL. When "location_type" is "0x07", it indicates that the location is in a control message transmitting this "location_type". When "location_type" is "0x08", it indicates that the location is a control message transmitted by the data path transmitting this "location_type".

  When "location_type" is "0x09", it indicates that the control message is transmitted by the data flow of UDP / IP transmitting this "location_type". When “location_type” is “0x0A”, it indicates that the control message is transmitted by a data flow of UDP / IP (version 4). When “location_type” is “0x0B”, it indicates that the control message is transmitted by the data flow of UDP / IP (version 6). When “location_type” is “0x0C”, it indicates that the stream is an elementary stream in MPEG2-TS distributed in an IP (version 6) broadcast network.

  Next No. No. 3 “if (location_type == 0x00) {” is assigned to “No. When the value of “location_type” of 2 is “0x00”, No. It shows that the area 4 is placed. No. 2 arranged next. The "packet_id" of 4 is a 16-bit area indicating the packet ID of the MMT packet.

  Next No. No. 5 “} else if (location_type == 0x01) {” When the value of “location_type” of 2 is “0x01”, No. Indicates that areas up to 9 are placed. No. 2 arranged next. The “ipv4_src_addr” of 6 is a 32-bit area indicating the IPv4 address of the transmission source. No. 2 arranged next. The “ipv4_dst_addr” of 7 is a 32-bit area indicating the IPv4 address of the destination. No. 2 arranged next. The “dst_port” of 8 is a 16-bit area indicating the port number of the destination. No. 2 arranged next. The “packet_id” of 9 is a 16-bit area indicating the packet ID of the MMT packet.

  Next No. Ten "} else if (location_type = = 0x02) {" are assigned to No. When the value of “location_type” of 2 is “0x02”, No. Indicates that up to 14 areas are placed. No. 2 arranged next. 11 “ipv6_src_addr” is a 128-bit area indicating the IPv6 address of the transmission source. No. 2 arranged next. Twelve "ipv6_dst_addr" is a 128-bit area indicating the IPv6 address of the destination. No. 2 arranged next. The 13 “dst_port” is a 16-bit area indicating the destination port number. No. 2 arranged next. 14 “packet_id” is a 16-bit area indicating the packet ID of the MMT packet.

  Next No. The 15 "} else if (location_type = = 0x03) {" is No. When the value of “location_type” of 2 is “0x03”, No. Indicates that up to 19 areas are placed. No. 2 arranged next. 16 “network_id” is a 16-bit area indicating the ID of the broadcast network transmitting the MPEG2-TS. No. 2 arranged next. 17 “MPEG_2_transport_stream_id” is an ID of MPEG2-TS. No. 2 arranged next. Eighteen "reserved" is a 3-bit reserved area. No. 2 arranged next. The 19 “MPEG_2_PID” is a PID of an MPEG2-TS packet transmitting an elementary stream.

  Next No. As for 20 "} else if (location_type = = 0x04) {", no. When the value of “location_type” of No. 2 is “0x04”, the No. in FIG. Indicates that up to 25 areas are placed. No. 2 arranged next. 21 “ipv6_src_addr” is a 128-bit area indicating the IPv6 address of the transmission source. No. 2 arranged next. 22 “ipv6_dst_addr” is a 128-bit area indicating the IPv6 address of the destination. No. 2 arranged next. The 23 "dst_port" is a 16-bit area indicating the port number of the destination. The No. in FIG. 24 "reserved" is a 3-bit reserved area. No. 2 arranged next. “MPEG_2_PID” of 25 is a PID of an MPEG2-TS packet transmitting an elementary stream.

  Next No. No. 26 “} else if (location_type == 0x05) {” When the value of “location_type” of 2 is “0x05”, No. Indicates that up to 30 areas are to be placed. No. 2 arranged next. "URL_length" of 27 is an 8-bit area indicating the number of bytes N1 of the URL. Next No. No. 28 “for (i = 0; i <N1; i ++) {” will be referred to as “No. It indicates that up to 30 areas are repeated N1 times, that is, the number of bytes of the URL. No. 2 arranged next. "URL_byte" of 29 is an area indicating 1 byte in the URL. Next No. No. 30 "}" is no. Corresponds to 28 "{".

  Next No. No. 31 "} else if (location_type = = 0x06) {" When the value of “location_type” of 2 is “0x06”, No. Indicates that up to 37 areas are placed. No. 2 arranged next. 32 “URL_length” is an 8-bit area indicating the number N 2 of bytes of the URL. Next No. No. 33 “for (i = 0; i <N2; i ++) {” is referred to as “No. It indicates that the area up to 35 is repeated N2 times, that is, the number of bytes of the URL. No. 2 arranged next. 34 "URL_byte" is an area indicating 1 byte in the URL. Next No. No. 35 "}" is no. Corresponds to 33 "{". No. 2 arranged next. “Byte_offset” 36 is a 16-bit area indicating the offset position from the beginning of the file indicated by the URL. No. 2 arranged next. The "length" of 37 is a 16-bit area indicating the number of bytes from the offset position.

  Next No. No. 38 "} else if (location_type = = 0x07) {" When the value of “location_type” of 2 is “0x07”, it indicates that nothing is placed.

  Next No. For example, “} else if (location_type == 0x08) {” of 39 is No. When the value of “location_type” of 2 is “0x08”, No. It shows that 40 areas are arranged. No. 2 arranged next. The “message_id” 40 is an 8-bit area indicating the ID of the control message.

  Next No. For example, "} else if (location_type = = 0x09) {" of 41 is No. When the value of “location_type” of 2 is “0x09”, No. Indicates that up to 43 areas are placed. No. 2 arranged next. 42 “packet_id” is a 16-bit area indicating the packet ID of the MMT packet. No. 2 arranged next. 43 “message_id” is an 8-bit area indicating the ID of the control message.

  Next No. No. 44 "} else if (location_type = = 0x0A) {" When the value of “location_type” of No. 2 is “0x0A”, the No. in FIG. Indicates that up to 49 areas are placed. No. 2 arranged next. 45 “ipv4_src_addr” is a 32-bit area indicating the source IPv4 address. No. 2 arranged next. 46 "ipv4_dst_addr" is a 32-bit area indicating the IPv4 address of the destination. The No. 1 in FIG. 47 “dst_port” is a 16-bit area indicating the port number of the destination. No. 2 arranged next. “Packet_id” of 48 is a 16-bit area indicating the packet ID of the MMT packet. No. 2 arranged next. 49 “message_id” is an 8-bit area indicating the ID of the control message.

  Next No. No. 50 "} else if (location_type == 0x0B) {" When the value of “location_type” of 2 is “0x0B”, No. Indicates that up to 55 areas are placed. No. 2 arranged next. 51 “ipv6_src_addr” is a 128-bit area indicating the source IPv6 address. No. 2 arranged next. 52 “ipv6_dst_addr” is a 128-bit area indicating the IPv6 address of the destination. No. 2 arranged next. 53 "dst_port" is a 16-bit area indicating the port number of the destination. No. 2 arranged next. The "packet_id" of 54 is a 16-bit area indicating the packet ID of the MMT packet. No. 2 arranged next. “Message_id” 55 is an 8-bit area indicating the ID of the control message.

  Next No. No. 56 “} else if (location_type == 0x0C) {” When the value of “location_type” of 2 is “0x0C”, No. It shows that the area up to 62 is placed. No. 2 arranged next. 57 "ipv4_src_addr" is a 32-bit area indicating the IPv4 address of the transmission source. No. 2 arranged next. The "ipv4_dst_addr" of 58 is a 32-bit area indicating the IPv4 address of the destination. No. 2 arranged next. 58 “dst_port” is a 16-bit area indicating the port number of the destination. No. 2 arranged next. 60 "reserved" is a 3-bit reserved area. No. 2 arranged next. “MPEG_2_PID” 61 is a PID of an MPEG2-TS packet transmitting an elementary stream. Next No. No. 62 "}" is no. Corresponds to 56 "{". Next No. 63 "}" is No. Corresponds to 1 "{".

  12 and 13 are tables showing the data structure of the package list table. In the table, no. Is a column indicating the serial number of the row in the table. The data structure is a field indicating the data structure of the package list table. The number of bits is a column indicating the number of bits of the data structure. The value is a column indicating the value taken by the data structure of the number of bits. The bit string notation is a field indicating the data format of the data structure of the number of bits. The bit string notation uimsbf is an abbreviation for unsigned integer most significant bit first. An unsigned integer, the most significant bit means the beginning. Also, the bit string notation char means a character.

  In FIG. “Package_List_Table () {” of 1 is referred to as “No. It represents that up to 30 "}" are the data structure of the package list table. No. placed at the top of the table. The “table_id” of 2 is an 8-bit area indicating the ID of the package list table. No. 2 arranged next. The "version" of 3 is an 8-bit area indicating the version number of the package list table. No. 2 arranged next. “Length” of 4 is a 16-bit area indicating the number of bytes of the package list table after the area.

No. 2 arranged next. “Num_of_package” 5 is an 8-bit area indicating the number N2 of packages for which the reference information is described in the package list table.
Next No. The “for (i = 0; i <N2; i ++) {” of 6 is hereinafter referred to as “No. It is shown to repeat the area up to 9 N2 times, that is, several minutes of the package that describes the reference information. No. 2 arranged next. “Package_id” of 7 is a 16-bit area indicating the package ID of the package describing the reference information to the MP table. In addition, this No. No. 7 in FIG. 9 to No. An area similar to 12 may be arranged so that an arbitrary-length package ID can be described. No. 2 arranged next. “MMT_general_location_info ()” of 8 is reference information to the MP table, and is an area indicating the reference information shown in FIG. 9 to FIG. The package list table includes these No. 7 and No. 8, the package ID is associated with the reference information (packet ID) to the MP table. Next No. 9 "}" is No. Corresponds to 6 "{".

No. 2 arranged next. The “num_of_ip_delivery” of 10 is an 8-bit area indicating the number N3 of IP services describing this reference information. Next No. 11 “for (i = 0; i <N3; i ++) {” are referred to as “No. It is shown that the area up to 29 is repeated N3 times, that is, several minutes of the IP service that describes the reference information.
No. 2 arranged next. 12 “transport_file_id” is a 32-bit area indicating a label for uniquely identifying a file to be transmitted by the IP service.
No. 2 arranged next. 13 “location_type” is an 8-bit area indicating the type of reference information. When "location_type" is "0x01", it indicates that the data flow is IPv4. When "location_type" is "0x02", it indicates that the location is UDP / IP (version 6).

  Next No. The “if (location_type == 0x01) {” of No. 14 is No. When the value of “location_type” of 13 is “0x01”, No. Indicates that up to 17 areas are placed. No. 2 arranged next. The 15 "ipv4_src_addr" is a 32-bit area indicating the IPv4 address of the transmission source. No. 2 arranged next. The 16 "ipv4_dst_addr" is a 32-bit area indicating the IPv4 address of the destination. No. 2 arranged next. The 17 “dst_port” is a 16-bit area indicating the port number of the destination.

  Next No. No. 18 “if (location_type == 0x02) {” is assigned to “No. When the value of “location_type” of 13 is “0x02”, No. Indicates that up to 21 areas are placed. No. 2 arranged next. The 19 "ipv6_src_addr" is a 128-bit area indicating the IPv6 address of the transmission source. No. 2 arranged next. 20 “ipv6_dst_addr” is a 128-bit area indicating the IPv6 address of the destination. No. 2 arranged next. 21 "dst_port" is a 16-bit area indicating the port number of the destination.

  In the next FIG. The “if (location_type == 0x05) {” of “22” corresponds to “No. When the value of “location_type” of 13 is “0x05”, No. Indicates that up to 27 areas are placed. No. 2 arranged next. The “URL_length” of 23 is an 8-bit area indicating the number of bytes N1 of the URL. Next No. 24 “for (i = 0; i <N1; i ++) {” are referred to as “No. It indicates that the area up to 26 is repeated N1 times, that is, the number of bytes of the URL. No. 2 arranged next. "URL_byte" of 25 is an area indicating 1 byte in the URL. Next No. No. 26 "}" is no. In correspondence with 24 "{", the next No. No. 27 "}" is no. Corresponds to 22 "{".

  No. 2 arranged next. 28 “descriptors ()” is an area indicating a descriptor related to an IP service. Next No. The 29 "}" are the numbers in FIG. In correspondence with 11 “{”, the next No. No. 30 "}" corresponds to No. 30 in FIG. Corresponds to 1 "{".

  FIG. 14 is a flowchart for explaining the operations of the designation acquisition unit 72, the reception control unit 73, and the control message processing unit 74. First, the designation acquisition unit 72 acquires designation of a desired service (Sa1). Next, the reception control unit 73 instructs the reception unit 70 to receive the IP data flow transmitting the desired service (Sa2). The correspondence between the service and the IP data flow may be stored in advance by the reception control unit 73, or information indicating the correspondence, such as AMT (Address Map Table), may be distributed from the service providing side. (Refer nonpatent literature 1 and 2).

  When the receiving unit 70 receives the IP data flow according to the instruction, the separating unit 71 separates the PA message stored in the MMT packet whose packet ID is “0” from the IP data flow. The control message processing unit 74 acquires the PA message separated by the separation unit 71 (Sa3). Next, the control message processing unit 74 acquires the MP table in the acquired PA message (Sa4), and the package ID of the MPT table is the package ID of the desired service acquired by the specification acquisition unit 72 in step Sa1. It is judged whether or not it matches (Sa5).

  The control message processing unit 74 may, for example, store the association between the service and the package ID in advance, and acquire the package ID of the desired service by referring to the association. Alternatively, information indicating the correspondence between the service and the package ID may be distributed from the service providing side, and the control message processing unit 74 may obtain the package ID of the desired service by referring to the information. .

  If it is determined in step Sa5 that they do not match (Sa5-No), the process proceeds to step Sa11. The control message processing unit 74 acquires the package list table in the PA message acquired in step Sa3 (Sa11). Next, the control message processing unit 74 refers to the acquired package list table, and acquires the packet ID associated with the package ID of the desired service (Sa12).

  The control message processing unit 74 instructs the separation unit 74 to separate the PA message of the acquired packet ID. The separating unit 74 separates the PA message of the instructed packet ID from the IP data flow received by the receiving unit 70. The control message processing unit 74 acquires the separated PA message. That is, the control message processing unit 74 acquires the PA message of the packet ID acquired in step Sa12 (Sa13).

  Next, the control message processing unit 74 acquires the MP table in the acquired PA message (Sa14), and proceeds to step Sa6. On the other hand, when it is determined in step Sa5 that they match (Sa5-Yes), the process directly proceeds to step Sa6.

  In step Sa6, the control message processing unit 74 instructs the separation unit 71 to separate the asset described in the acquired MP table. The separation unit 71 inputs the video stream to the video decoding unit 75, the audio stream to the audio decoding unit 76, and the data stream to the data rendering unit 77 according to the instruction. Do. As a result, the output device 18 displays the video of the package and outputs the audio.

Since the MP table of the desired service is repeatedly transmitted by the received IP data flow, the control message processing unit 74 monitors the MP table (Sa7).
The control message processing unit 74 determines whether or not there is a change from the previous one in the transmitted MP table (Sa8). If it is determined that there is a change (Sa8-Yes), the control message processing unit 74 reacquires the MP table (Sa9), and returns to step Sa6.

  When it is determined in step Sa8 that there is no change (Sa8-No), the designation acquisition unit 72 determines whether the desired service has been changed (Sa10). If the desired service has not been changed (Sa10-No), the process returns to step Sa7. When the desired service has been changed, the process returns to step Sa1.

  As described above, the distribution system 10 includes the control message generation device 11, the distribution device 16, and the reception device 17. The control message generation device 11 includes a first MP table (first table) including reference information to each of the assets constituting the first package, and reference information to the second MP table (second table). Generating a first PA message (first control message) including the package list table including Also, the control message generator 11 generates a second PA message (second control message) including the second MP table. The distribution device 16 distributes the first and second PA messages generated by the control message generation device 11 using an IP data flow (data flow). The receiver 17 receives the data flow.

  As a result, the distribution system 10 can make the reception apparatus 17 be able to receive the first package only by acquiring only the first control message, that is, one hop. Also, for the second package, if the first control message and the second control message are obtained, it can be made receivable in two hops. Therefore, the expected value of the number of hops until the package can be received can be suppressed.

The reception device 17 further includes a designation acquisition unit 72, a reception unit 70, a separation unit 71, and a control message processing unit 74. The designation acquisition unit 72 acquires information for designating a desired package. The receiver 70 receives an IP data flow. The separation unit 71 separates the first PA message from the IP data flow. The control message processing unit 74 refers to the first MP table included in the first PA message, and separates the separation of the first MP package when the first package matches the desired package. It instructs the part 71.
Thus, the receiving device 17 can receive the first package with one hop.

Further, the control message processing unit 74 refers to the first MP table included in the first PA message, and includes the first PA message when the first package does not match the desired package. A package list table to be acquired, to obtain reference information to a second MP table corresponding to a desired package, and using the acquired reference information to include a second MP table corresponding to the desired package; The separation unit 71 is instructed to separate the two PA messages.
Thus, the receiving device 17 can receive the second package with two hops.

  In the above embodiment, if there is only one package included in the IP data flow at the same time, the PA list message may not include the package list table in the PA message with the packet ID “0”. You may include a package list table that contains only information about one package included in the package, or you may set the value of "num_of_package" to "0" and create a package list table that does not include reference information about packages. .

  Also, in the above embodiment, the MP table and the package list table are described as being stored in the PA message, but may be stored in other control messages. However, it is desirable that the control message storing the package list table together with the MP table is a PA message whose packet ID is “0”. This is because the PA message with the packet ID “0” is a control message that the receiving device 17 first obtains.

Modification 1 of Embodiment
In the above-described embodiment, the control message generator 11 stores the package list table only in the PA message of which the packet ID is “0”, but may store it in other PA messages. FIG. 15 is a conceptual diagram showing a configuration of IP data flow in the first modification. In the figure, the parts corresponding to the parts in FIG.

  The IP data flow DFa differs from the IP data flow DF of FIG. 4 in that it includes a PA message PA2 instead of the PA message PA. The PA message PA2 includes a package list table PL2 in addition to the MP table MP2. The package list table PL2 contains at least reference information to the MP table other than the MP table MP2. The package list tables PL1 and PL2 may include reference information to all the MP tables transmitted in the IP data flow DFa.

Modification 2 of Embodiment
Hereinafter, a second modification of the embodiment will be described with reference to the drawings. The present modification is different from the above embodiment in the data structure of the MP table, reference information (MMT_general_location_info ()), and the package list table. FIG. 16, FIG. 17 and FIG. 18 are tables showing the data structure of the MP table in this modification. The data structure shown in these figures differs from the data structures shown in FIG. 6, FIG. 7, and FIG. 8 in the following four points.

  The first point is that in the MP table of this modification, No. 1 in FIG. The value of “table_id” of 2 is “0x20”. The second point is that the MP table of this modification is No. 7 in FIG. No. 23 to No. Instead of No. 28 in FIG. No. 23 to No. It is a point having 28. The third point is that the MP table of this modification is No. 7 in FIG. Instead of No. 28 in FIG. 29 is a point having "asset_type". The fourth point is that the MP table of this modification is No. 7 in FIG. No. 30 to No. It is a point which does not have 36.

  The above second point will be described below. The numbers in FIG. The 23 "identifier_type" is also referred to as an identifier type, and is an 8-bit area indicating the ID system of the MMTP packet flow stored thereafter. Here, the value of “identifier_type” is “0x00” indicating that the asset ID is stored. No. The "asset_id_scheme" 24 is also referred to as an asset ID format, and is a 32-bit area indicating the format of an asset ID to be stored subsequently. No. The “asset_id_length” 25 is also referred to as an asset ID length, and is an 8-bit area indicating the length of an asset ID byte stored in bytes thereafter. Next No. No. 26 “for (i = 0; i <N4; i ++) {” is referred to as “No. It shows that the area up to 28 is repeated N4 times, that is, the number of asset ID lengths. No. 2 arranged next. 27 “asset_id_byte” is also an asset ID byte, and is an area indicating one byte in the asset ID. Next No. No. 28 "}" is no. Corresponds to 26 "{".

  The above third point will be described below. The numbers in FIG. 29 “asset_type” is also called an asset type. This is a 32-bit area indicating the type of asset indicated by the 27 asset ID bytes. As for "asset_type", when the value is "hvc1", the type of asset is ITUT-T recommendation H. It shows that it is HEVC specified at 265. “Asset_type” indicates that the type of asset is a sound of ISO / IEC 14496-3 when the value is “mp4a”.

  “Asset_type” indicates that the type of asset is timed text (subtitles / superimposed characters) when the value is “stpp”. "Asset_type" indicates that the asset type is an application when the value is "aapp". "Asset_type" indicates that the asset type is synchronous general-purpose data when the value is "asgd". “Asset_type” indicates that the asset type is asynchronous general-purpose data when the value is “aagd”.

  FIG. 19 and FIG. 20 are tables showing the data structure of reference information (MMT_general_location_info ()) in this modification. The data structure shown in these figures differs from the data structures shown in FIG. 9, FIG. 10, and FIG. 11 in the following four points. The numbers in FIG. 31 to No. 46 and FIG. 47 to No. The point of not having 62 is different.

  FIG. 21 and FIG. 22 are tables showing the data structure of the package list table in this modification. The data structure shown in these figures differs from the data structures shown in FIGS. 12 and 13 in the following two points. The first point is that the package list table in this modification is No. 1 in FIG. Instead of No. 7 in FIG. 7 to No. It is a point having ten. The numbers in FIG. The “MMT_package_id_length” of 7 is also referred to as a package ID length, and is an 8-bit area indicating the length of the package ID byte stored in the subsequent byte unit. Next No. No. 8 “for (j = 0; j <M; j ++) {” is assigned to “No. It is shown that the area 9 is repeated M times, that is, the length of the package ID byte. No. 2 arranged next. 9, “MMT_package_id_byte” is also referred to as a package ID byte, and is an 8-bit area indicating one byte in the package ID. Next No. No. 10 "}" is no. Corresponds to 8 "{".

  The second point is that the package list table in this modification is No. 1 in FIG. 22 instead of No. 28 in FIG. No. 32 to No. 34 is a point. In FIG. The "descriptor_loop_length" of 32 is also referred to as a descriptor length, and is a 16-bit area indicating the full byte length of the descriptor to be stored later. Next No. No. 33 “for (j = 0; j <M; j ++) {” is assigned to “No. It is shown that 33 areas are repeated M times, that is, the descriptor length. Next No. 34 “descriptor ()” is also referred to as a descriptor area, and is one byte in an area for a descriptor indicating detailed information of the IP service. Next No. 34 "}" is no. Corresponds to 32 "{".

Note that any or all of the MP table, the MMT_general_location_info (), and the package list table in the above-described modification 1 may be the same as in the modification 2.
Moreover, in the above-mentioned modified example 2, all of the MP table, MMT_general_location_info (), and the package list table are different from the above-described embodiment, but the differences are the MP table, MMT_general_location_info (), the package list table. It may be a part.

  Also, a program for realizing the functions of the control message generator 11 and the receiver 17 in FIG. 1 is recorded in a computer readable recording medium, and the program recorded in the recording medium is read into a computer system and executed. These devices may be realized by Here, the “computer system” includes an OS and hardware such as peripheral devices.

  The term "computer-readable recording medium" refers to a storage medium such as a flexible disk, a magneto-optical disk, a ROM, a portable medium such as a ROM or a CD-ROM, or a hard disk built in a computer system. Furthermore, “computer-readable recording medium” dynamically holds a program for a short time, like a communication line in the case of transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, the volatile memory in the computer system which is the server or the client in that case, and the one that holds the program for a fixed time is also included. The program may be for realizing a part of the functions described above, or may be realized in combination with the program already recorded in the computer system.

In addition, each functional block of the control message generation device 11 in FIG. 2 and the reception device 17 in FIG. 3 may be individually chipped, or a part or all of them may be integrated and chipped. Further, the method of circuit integration is not limited to LSI's, and implementation using dedicated circuitry or general purpose processors is also possible. Either hybrid or monolithic may be used. Some of the functions may be implemented by hardware and some may be implemented by software.
Further, when a technology such as integrated circuit substitution for LSI emerges with the advance of semiconductor technology, it is also possible to use an integrated circuit according to the technology.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like within the scope of the present invention are also included.

DESCRIPTION OF SYMBOLS 10 ... Distribution system 11 ... Control message production | generation apparatus 12 ... Video transmission apparatus 13 ... Audio transmission apparatus 14 ... Data transmission apparatus 15 ... Multiplexing apparatus 16 ... Distribution apparatus 17 ... Reception apparatus 18 ... Output apparatus 21 ... MP table production | generation part 22 ... Package List table generation unit 23 ... PA message generation unit 70 ... reception unit 71 ... separation unit 72 ... specification acquisition unit 73 ... reception control unit 74 ... control message processing unit 75 ... video decoding unit 76 ... audio decoding unit 77 ... data rendering unit 78 ... Video synthesis unit 79 ... Speech synthesis unit

Claims (1)

A table generation unit that generates a first table including reference information to each of the assets constituting the first package, and a second table including reference information to each of the assets constituting the second package;
A package list table generation unit that generates a package list table including reference information to the second table;
A control message generator for generating a first control message including the first table and the package list table, and a second control message including the second table;
A multiplexing unit that sets a packet ID of an MMT packet storing the first control message generated by the control message generation device to "0";
Delivery system equipped with.

Images