Transmission method and transmission apparatus

Abstract

To satisfactorily realize a hybrid service of broadcasting and communication.SOLUTION: A transmission stream is generated by multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component in a time-division manner. The transmission stream is transmitted through a predetermined transmission path. Acquisition information of a component of the communication path including at least location information and protocol identification information is inserted into the second transmission packet. The reception side can satisfactorily receive the transmission stream having the transmission packet including the component of the communication path on the basis of the acquired information. For example, the acquisition information further includes packet identification information. In this case, even if a plurality of transmission packets are multiplexed in the transmission stream, a desired transmission packet can be selectively acquired based on the packet identification information.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present technology relates to a transmission method and a transmission device. [Background technology]

[0002] In current broadcasting systems, the MPEG-2 TS (Moving Picture Experts Group-2 Transport Stream) method and the RTP (Real Time Protocol) method are widely used as media transport methods (see, for example, Patent Document 1). The MMT (MPEG Media Transport) method (see, for example, Non-Patent Document 1) is being considered as a next-generation digital broadcasting method. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-153291 [Non-patent literature]

[0004] [Non-Patent Document 1] ISO / IEC DIS 23008-1:2013(E) Information technology-High efficiency coding and media delivery in heterogeneous environments-Part1:MPEG media transport(MMT) Summary of the Invention [Problem to be solved by the invention]

[0005] The purpose of this technology is to enable successful realization of hybrid broadcasting and communication services. [Means for solving the problem]

[0006] The concept of this technology is: a transmission stream generating unit that generates a transmission stream by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component; a transmitting unit that transmits the transmission stream through a predetermined transmission path; an information insertion unit that inserts, into the second transmission packet, acquisition information of a component of a communication path, the acquisition information including at least location information and protocol identification information; Located in the transmitting device.

[0007] In the present technology, a transmission stream generating unit generates a transmission stream by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component. For example, the transmission packets may be MMT (MPEG Media Transport) packets. A transmitting unit transmits this transmission stream to a receiving side through a predetermined transmission path. For example, the predetermined transmission path may be a broadcast transmission path.

[0008] The information inserting unit inserts, into the second transmission packet, acquisition information for a component of the communication path, including at least location information and protocol identification information. For example, the protocol identification information may be information for identifying at least one of multicast delivery, MMTP / UDP delivery, MMTP / TCP delivery, MMTP / HTTP delivery, and MPU / HTTP delivery.

[0009] In this case, for example, when the protocol identification information indicates MMTP / UDP delivery, the acquisition information may include a parameter specifying UDP in addition to the URL. Also, in this case, for example, when the protocol identification information indicates MMTP / TCP delivery, the acquisition information may include a parameter specifying TCP in addition to the URL.

[0010] In this way, in the present technology, acquisition information of a component of a communication path, which includes at least location information and protocol identification information, is inserted into the second transmission packet, and therefore, the receiving side can successfully receive a transmission stream having a transmission packet including a component of the communication path based on the acquisition information.

[0011] In the present technology, for example, the acquisition information may further include packet identification information, in which case, even if transmission packets of multiple components are multiplexed in a transmission stream, it becomes possible to selectively acquire transmission packets of a desired component based on the packet identification information.

[0012] Another concept of the present technology is a receiving unit that receives a transmission stream obtained by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component through a predetermined transmission path; The second transmission packet contains acquisition information for a component of a communication path, the acquisition information including at least location information and protocol identification information; and a communication unit configured to receive, via a network, a transmission stream having third transmission packets including a predetermined component in accordance with the protocol indicated by the protocol identification information, based on the location information and the protocol identification information; It is in the receiving device.

[0013] In this technology, a receiving unit receives a transmission stream through a predetermined transmission path, in which a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component are time-division multiplexed. The second transmission packet contains acquisition information about the component of the communication path, which includes at least location information and protocol identification information.

[0014] The communication unit sends a request to the server based on the location information and the protocol identification information, and a transmission stream having third transmission packets including a predetermined component is received from the server via a network using the protocol indicated by the protocol identification information. For example, the protocol identification information may be information for identifying at least one of multicast delivery, MMTP / UDP delivery, MMTP / TCP delivery, MMTP / HTTP delivery, and MPU / HTTP delivery.

[0015] For example, when the protocol identification information indicates MMTP / UDP delivery, the acquisition information may include a parameter specifying UDP in addition to the URL, and the communication unit may receive a transmission stream having the third transmission packet from the server via the network using the MMTP / UDP delivery protocol by making a request to the server using the URL and the parameter specifying UDP.

[0016] Also, for example, when the protocol identification information indicates MMTP / TCP delivery, the acquisition information may include a parameter specifying TCP in addition to the URL, and the communication unit may make a request to the server using the URL and the parameter specifying TCP, thereby receiving a transmission stream having a third transmission packet corresponding to the parameter from the server via the network using the MMTP / TCP delivery protocol.

[0017] Also, for example, when the protocol identification information indicates MMTP / HTTP delivery, the acquisition information may include a URL, and the communication unit may sequentially send requests to the server using parameters indicating the URL and the MPU sequence number, thereby sequentially receiving MMT packets including an MPU with an MPU sequence number corresponding to the parameters from the server via the network, and the parameter indicating the MPU sequence number in the first request may represent the MPU sequence number at the timing of the first request.

[0018] Also, for example, when the protocol identification information indicates MPU / HTTP delivery, the acquisition information includes a URL, and the communication unit sequentially sends requests to the server using parameters indicating the URL and the MPU sequence number, thereby sequentially receiving MPUs with MPU sequence numbers corresponding to the parameters from the server via the network, and the parameter indicating the MPU sequence number in the first request may represent the MPU sequence number at the time of the first request.

[0019] In this way, in this technology, by making a request to the server based on the location information and protocol identification information inserted and transmitted in the second transmission packet, a transmission stream having a third transmission packet including a predetermined component is received from the server via the network using the protocol indicated by the protocol identification information, thereby enabling successful reception of a transmission stream having transmission packets including a component of the communication path.

[0020] In the present technology, for example, the acquisition information of the component of the communication path may further include packet identification information, and the communication unit may extract the received third transmission packet from the transmission stream having this third transmission packet based on the packet identification information. In this case, even if transmission packets of multiple components are multiplexed in the transmission stream, it is possible to selectively acquire the transmission packet of a desired component based on this packet identification information.

[0021] Furthermore, another concept of the present technology is a receiving unit that receives a transmission stream obtained by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component through a predetermined transmission path; The second transmission packet contains acquisition information for a component of a communication path, the acquisition information including at least location information and protocol identification information; and The transmission stream receiving unit further includes a processing unit for processing the transmission stream received by the receiving unit. It is in the receiving device. [Effects of the Invention]

[0022] This technology makes it possible to effectively realize hybrid broadcasting and communication services. Note that the effects described in this specification are merely examples and are not intended to be limiting, and additional effects may also be provided. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a block diagram showing an example of the configuration of a broadcasting and communication hybrid system according to an embodiment. [Figure 2] FIG. 10 is a diagram illustrating a stack model of an example of an MMT / broadcast signal configuration. [Figure 3] FIG. 1 is a diagram illustrating an example of the configuration of an MMT broadcast stream. [Figure 4] FIG. 1 is a diagram showing an image of a broadcast signal of one channel (broadcast program) transmitted from a broadcast transmission system to a receiving terminal. [Figure 5] 1A and 1B are diagrams illustrating an example of the configuration of an MMT packet and an example of the configuration of an MMTP payload. [Figure 6] FIG. 10 is a diagram illustrating a stack model of an example of a signal configuration of MMT / communication. [Figure 7] 1 is a diagram illustrating an example of the configuration of a PA message (Package Access Message) and an MP table (MPT: MMT Package Table). FIG. [Figure 8] FIG. 10 is a diagram illustrating the main parameters of a PA message. [Figure 9] FIG. 10 is a diagram illustrating the main parameters of an MP table. [Figure 10] FIG. 10 is a diagram illustrating an example of the structure (Syntax) of a PA message. [Figure 11] FIG. 10 is a diagram showing an example of the structure (Syntax) of an MP table (MPT). [Figure 12]A diagram showing a portion of an example structure (Syntax) of "MMT_general_location_info()". [Figure 13] FIG. 10A is a diagram illustrating a receiving sequence when receiving an asset distributed using a multicast distribution protocol. [Figure 14] FIG. 1B is a diagram illustrating a receiving sequence when receiving an asset distributed using the MMTP / UDP distribution protocol. [Figure 15] FIG. 1C is a diagram illustrating a receiving sequence when receiving an asset distributed using the MMTP / TCP distribution protocol. [Figure 16] FIG. 1D is a diagram illustrating a receiving sequence when receiving an asset distributed using the MMTP / HTTP distribution protocol. [Figure 17] FIG. 10 is a diagram for explaining a cutout process in an MMTP / HTTP multiplexed stream. [Figure 18] FIG. 10E is a diagram illustrating a reception sequence when receiving an asset distributed using the MPU / HTTP distribution protocol. [Figure 19] FIG. 1 is a block diagram showing an example of the configuration of a broadcast transmission system. [Figure 20] FIG. 2 is a block diagram showing an example of the configuration of a receiving terminal. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, modes for carrying out the invention (hereinafter referred to as "embodiments") will be described. The description will be made in the following order. 1. Embodiment 2. Variations

[0025] <1. Embodiment> [Example of a hybrid broadcasting and communication system configuration] 1 shows an example of the configuration of a broadcasting and communication hybrid system 10. In the broadcasting and communication hybrid system 10, a broadcasting transmission system 100 and a distribution server 300 are arranged on the transmitting side, and a receiving terminal 200 is arranged on the receiving side. The distribution server 300 is connected to the receiving terminal 200 via a communication network 400.

[0026] The broadcast transmission system 100 transmits IP (Internet Protocol) broadcast signals that include components (assets) such as video and audio as transmission media. The distribution server 300 distributes a transmission stream, in which IP packets that include components (assets) such as video and audio as transmission media are consecutively arranged, to a receiving side via a communication network 400, for example, in response to a request from the receiving side.

[0027] The receiving terminal 200 receives IP broadcast signals sent from the broadcast transmission system 100, and also receives a transmission stream in which IP packets are arranged consecutively from the distribution server 300. The receiving terminal 200 acquires transmission media (components) such as video and audio to be presented from the received signal via such hybrid transmission of broadcast and communication, and presents images, sounds, etc.

[0028] The IP broadcast signal contains acquisition information for the communication path components. This acquisition information includes at least location information and protocol identification information. Based on this acquisition information, the receiving terminal 200 makes a request to the distribution server 300 and receives the transmission stream according to the protocol indicated by the protocol identification information.

[0029] Figure 2 shows a stack model of an example of MMT / broadcast signal configuration. A TLV (Type Length Value) transmission packet exists in the lower layer. An IP packet is carried on top of this TLV transmission packet. There are also TLV transmission packets that carry transmission control signals as signaling information.

[0030] The IP packet carries the User Datagram Protocol (UDP), and the MPEG Media Transport (MMT) packet carries the UDP. The payload of the MMT packet contains an MMT Fragment Unit (MFU) containing coded data for components such as video and audio, or a signaling message containing information about the transmission media.

[0031] Figure 3 shows an example of the structure of an MMT broadcast stream. Figure 3(a) shows a video elementary stream (Video ES). This video elementary stream is divided into chunks of a specified size and placed in the payload section of an MFU, as shown in Figure 3(b).

[0032] As shown in Figure 3(c), an MMT payload header is added to the MFU to form an MMTP payload. Then, as shown in Figure 3(d), an MMT header is added to this MMTP payload to form an MMT packet. Note that some MMT packets contain signaling messages in the payload section. As shown in Figure 3(e), a UDP header, IP header, and TLV header are added to the MMT packet to generate the TLV packet that constitutes the MMT broadcast stream.

[0033] Although not shown in the figure, there are also TLV packets that contain MMT packets for other components such as audio. This MMT broadcast stream has a first packet (MMT packet) that contains the transmission media (component) and a second packet (MMT packet) that contains signaling information.

[0034] 4 shows an image of a broadcast signal of one channel (broadcast program) transmitted from the broadcast transmission system 100 to the receiving terminal 200. This broadcast signal includes MMT packets including video, audio, etc. as well as MMT packets including signaling messages. As the signaling message, for example, there is a PA message including an MP table, etc.

[0035] Figure 5(a) shows an example of the structure of an MMT packet. An MMT packet consists of an MMT packet header (MMTP header) and an MMTP payload. The 2-bit field "V" indicates the version of the MMT protocol. When following the MMT standard version 1, this field is set to "00". The 1-bit field "C" indicates packet counter flag information (packet_counter_flag), and is set to "1" if a packet counter flag exists. The 2-bit field "FEC" indicates the FEC type (FEC_type).

[0036] The 1-bit field "X" indicates extension header flag (extension_flag) information and is set to "1" when the header of the MMT packet is extended. In this case, the "header_extension" field described below exists. The 1-bit field "R" indicates RAP flag (RAP_flag) information and is set to "1" when the MMT payload transmitted by this MMT packet includes the beginning of a random access point.

[0037] The 6-bit field "type" is payload type information and indicates the data type of the MMTP payload. For example, "0x00" indicates that the payload is an MPU (Media Processing Unit), and "0x02" indicates that the payload is a signaling message.

[0038] The 16-bit field "packet_id" indicates the packet identifier (packet_id) to identify the data type of the payload. The 32-bit field "timestamp" indicates the timestamp for transmission, i.e., the time when the MMT packet leaves the sender. This time is expressed in NTP short format. The 32-bit field "packet_sequence_number" indicates the sequence number of the MMT packet with the same packet identifier (packet_id). The 32-bit field "packet_counter" indicates the order of MMT packets in the same IP data flow, regardless of the value of the packet identifier (packet_id).

[0039] When the 1-bit flag information of "X" above is "1", the 32-bit field of "packet_counter" is followed by the field of "header_extension", which is the MMT extension header. This is followed by the fields of "payload data" and "source_FEC_payload_ID", which make up the MMTP payload.

[0040] Figure 5(b) shows an example of the structure (Syntax) of the MMTP payload placed in the "payload data" field of the above-mentioned MMT packet. Note that this example shows the case of MPU mode, where the "type" of the MMT header is "0x00". Header information comes first. The 16-bit "length" field indicates the byte size of the entire MMTP payload. The 4-bit "FT" field indicates the field type. "0" indicates that "MPU metadata" is included, "1" indicates that "Movie Fragment metadata" is included, and "2" indicates that "MFU" is included.

[0041] Here, an MFU (MMT Fragment Unit) is a fragment of an MPU. For example, in the case of video, this MFU can be set to correspond to one NAL unit. Also, for example, when transmitting over a communication network transmission path, this MFU can be configured with one or more MTU sizes.

[0042] Furthermore, an MPU starts from a random access point (RAP) and includes one or more access units (AU). Specifically, for example, the pictures of one GOP (Group Of Pictures) may constitute one MPU. This MPU is defined for each asset (component). Therefore, a video MPU containing only video data is created from a video asset, and an audio MPU containing only audio data is created from an audio asset.

[0043] The 1-bit flag "T" indicates whether timed media or non-timed media is being transmitted. "1" indicates timed media, and "0" indicates non-timed media.

[0044] The 2-bit field "f_i" indicates whether the "DU payload" field contains an integer number of data units (DUs) or the first, middle, or last fragment of a fragment obtained by fragmenting a data unit. "0" indicates that an integer number of data units is contained, "1" indicates that the first fragment is contained, "2" indicates that the middle fragment is contained, and "3" indicates that the last fragment is contained.

[0045] The 1-bit flag information in "A" indicates whether the "DU payload" field contains multiple data units. "1" indicates that it contains one, and "0" indicates that it does not. The 8-bit field in "frag_counter" indicates which fragment it is when "f_i" is 1 to 3.

[0046] The 32-bit field "MPU_sequence_number" is a number indicating the order of the MPU and is information for identifying the MPU. For example, if one GOP constitutes one MPU, when the "MPU_sequence_number" of one GOP is "i", the "MPU_sequence_number" of the next GOP will be "i+1".

[0047] After this "MPU_sequence_number" field, the "DU_length", "DU_header", and "DU_payload" fields are placed. The 16-bit "DU_length" field does not exist if "A=0" is set as described above, that is, if the "DU payload" field does not contain multiple data units. The "DU_header" field does not exist if "FT=0 / 1" is set, that is, if the field contains "MPU metadata" or "Movie Fragment metadata".

[0048] Figure 6 shows a stack model of an example signal configuration for MMT / communication. Possible delivery options for MMT / communication are (A) multicast delivery, (B) MMTP / UDP delivery, (C) MMTP / TCP delivery, (D) MMTP / HTTP delivery, and (E) MPU / HTTP delivery.

[0049] "(A) Multicast distribution" In the case of multicast distribution, IP packets exist at the lower layer. UDP (User Datagram Protocol) is carried on top of this IP packet. MMT (MPEG Media Transport) packets are then carried on top of the UDP. The payload of this MMT packet contains MPUs that contain coded data for components such as video and audio.

[0050] This multicast delivery is the most desirable method for hybrid broadcasting and communication use, taking congestion countermeasures into consideration. In addition, this multicast delivery uses UDP transmission, which has good transmission efficiency, but there is a problem with packet loss, so AL-FEC (Application Layer-Forward Error Correction) may be required.

[0051] In addition, in the case of multicast distribution, only receiving terminals directly connected to the managed network can use it. In addition, in the case of multicast distribution, there are cases where the multicast IP stream transmits an MMTP stream in which multiple assets (components) are multiplexed, and cases where it transmits an MMTP stream containing only a single asset.

[0052] "(B)MMTP / UDP Delivery" In the case of MMTP / UDP delivery, the lower layer is an IP packet. On top of this IP packet is a User Datagram Protocol (UDP). On top of the UDP is an MMT packet. The payload of this MMT packet contains an MPU, which contains the encoded data for components such as video and audio.

[0053] In the case of MMTP / UDP delivery, since it is unicast, there are congestion issues when used in hybrid broadcasting and communication. Also, in the case of MMTP / UDP delivery, since it is UDP transmission, transmission efficiency is good, but AL-FEC may be required. In addition, in the case of multicast delivery, it is better than TCP in terms of total delay and synchronization.

[0054] Also, since this MMTP / UDP distribution is unicast, it can be widely used on general internet-connected devices, but depending on the router settings, it may not be available by default. With this MMTP / UDP distribution, there are cases where the IP stream transmits an MMTP stream in which multiple assets (components) are multiplexed, and cases where it transmits an MMTP stream containing only a single asset.

[0055] "(C)MMTP / TCP distribution" In the case of MMTP / TCP delivery, IP packets exist at the lower layer. TCP (Transmission Control Protocol) is carried on top of this IP packet. MMT packets are then carried on top of TCP. The payload of these MMT packets contains MPUs that contain coded data for components such as video and audio.

[0056] This MMTP / TCP delivery is unicast, so it can be used by a wide range of general-purpose Internet-connected devices. Also, because this MMTP / TCP delivery is unicast, there are congestion issues when using it as a hybrid broadcasting / communication system. Also, while this MMTP / TCP delivery sacrifices efficiency because it uses TCP transmission, it does allow for retransmission, so AL-FEC is not required.

[0057] In addition, in the case of this MMTP / TCP distribution, there are cases where the IP stream transmits an MMTP stream in which multiple assets (components) are multiplexed, and cases where it transmits an MMTP stream containing only a single asset.

[0058] "(D)MMTP / HTTP distribution" In the case of MMTP / HTTP delivery, IP packets exist at the lower layer. TCP is placed on top of these IP packets. HTTP (Hyper Text Transfer Protocol) is placed on top of TCP, and MMT packets are placed on top of that. The payload of these MMT packets contains MPUs that contain coded data for components such as video and audio.

[0059] In the case of MMTP / HTTP delivery, since it uses HTTP, it can be used on a wide range of general-purpose Internet-connected devices. Also, since this MMTP / HTTP delivery is unicast, there are congestion issues when used in a hybrid broadcast / communication environment. In addition, since this MMTP / HTTP delivery uses TCP transmission, efficiency is sacrificed, but retransmission is possible, so AL-FEC is not required.

[0060] In addition, in the case of this MMTP / HTTP distribution, there are cases where the IP stream transmits an MMTP stream in which multiple assets (components) are multiplexed, and cases where it transmits an MMTP stream containing only a single asset.

[0061] "(E)MPU / HTTP Streaming" In the case of MPU / HTTP delivery, the lower layer is an IP packet. TCP is placed on top of this IP packet. HTTP is placed on top of TCP, and the payload of this HTTP packet contains an MPU containing encoded data for components such as video and audio.

[0062] This MPU / HTTP distribution uses HTTP, so it can be used on a wide range of general-purpose internet-connected devices. Furthermore, because this MPU / HTTP distribution is unicast, there are congestion issues when used in a hybrid broadcast / communication environment. Furthermore, while this MPU / HTTP distribution uses TCP transmission, it sacrifices efficiency, but because retransmission is possible, AL-FEC is not required.

[0063] Furthermore, with MPU / HTTP distribution, transmission efficiency is better than with MMTP / HTTP distribution because MMT packets are not involved, but conversely, there is the issue of information loss, such as the MMTP header. Also, with MPU / HTTP distribution, the receiving terminal obtains the individual MPU files of a single asset (component) via HTTP.

[0064] Fig. 7 shows a schematic structure of a PA message (Package Access Message) and an MP table (MPT: MMT Package Table). Fig. 8 shows an explanation of the main parameters of the PA message, and Fig. 9 shows an explanation of the main parameters of the MP table.

[0065] "Message_id" is a fixed value that identifies the PA message in various signaling information. "Version" is an 8-bit integer value that indicates the version of the PA message. For example, if even some of the parameters that make up the MP table are updated, it is incremented by +1. "Length" is the number of bytes that indicates the size of the PA message, counted from immediately after this field.

[0066] The "extension" field contains index information for the table placed in the payload field. This field contains the fields "table_id", "table_version", and "table_length" for each table. "table_id" is a fixed value that identifies the table. "table_version" indicates the version of the table. "table_length" is the number of bytes that indicates the size of the table.

[0067] The payload field of the PA message contains an MP table (MPT) and a predetermined number of other tables. The structure of the MP table will be described below.

[0068] "table_id" is a fixed value that identifies the MP table in various signaling information. "version" is an 8-bit integer value that indicates the version of the MP table. For example, if even some of the parameters that make up the MP table are updated, it is incremented by +1. "length" is the number of bytes that indicates the size of the MP table, counted from immediately after this field.

[0069] "pack_id" is identification information for the entire package, which is made up of all assets (components) transmitted via broadcasting and communication. This identification information is text information. "pack_id_len" indicates the size (number of bytes) of that text information. The "MPT_descripors" field is a storage area for descriptors related to the entire package. "MPT_dsc_len" indicates the size (number of bytes) of that field.

[0070] "num_of_asset" indicates the number of assets (components) that make up the package. The following asset loops are placed for this number of elements. "asset_id" is information that uniquely identifies the asset (asset ID). This identification information is text information. "asset_id_len" indicates the size (number of bytes) of that text information. "gen_loc_info" is information that indicates the location from which the asset was obtained. The "asset_descriptors" field is the storage area for descriptors related to the asset. "asset_dsc_len" indicates the size (number of bytes) of that field.

[0071] FIG. 10 shows an example structure (Syntax) of the PA message described above. FIG. 11 shows an example structure (Syntax) of the MP table (MPT) described above. The "gen_loc_info" field in FIG. 7 corresponds to the "asset_location" field in FIG. 11, and multiple "MMT_general_location_info()" can be placed as information indicating the location of the asset acquisition destination. The "asset_descriptors" field in FIG. 7 corresponds to the "asset_descriptors" field in FIG. 11.

[0072] Figure 12 shows part of the structure (Syntax) of "MMT_general_location_info()". The 8-bit field of "location_type" indicates the type of information indicating the location of the asset acquisition destination (hereinafter referred to as "location information" where appropriate). For assets distributed using the above-mentioned (A) multicast distribution protocol, "location_type" is set to "0x01" or "0x02", and the source address (ipv4_src_addr, ipv6_src_addr), destination address (ipv4_dst_addr, ipv6_dst_addr), destination port number (dst_port), and packet identifier (packt_id) are inserted as location information. In this case, "location_type" identifies it as multicast distribution.

[0073] Furthermore, for assets delivered using the above-mentioned (B) MMTP / UDP delivery, (C) MMTP / TCP delivery, (D) MMTP / HTTP delivery, or (E) MPU / HTTP delivery protocols, "location_type" is set to "0x05", and a URL (Uniform Resource Locator) is placed as location information.

[0074] Here, if the asset is distributed using the (B) MMTP / UDP distribution protocol, "rtsp: / / ~.mmt" is specified as the schema, and a parameter specifying UDP and a parameter specifying the packet identifier (packet_id) are added in the query field. Ultimately, the URL in this case is expressed as "rtsp: / / ~.mmt?pr=udp&pid=1". In this case, "rtsp" and "pr=udp" identify it as MMTP / UDP distribution.

[0075] Furthermore, if the asset is distributed using the (C)MMTP / TCP distribution protocol, "rtsp: / / ~.mmt" is specified as the schema, and a parameter specifying TCP and a parameter specifying the packet identifier (packet_id) are added in the query field. In this case, the URL is expressed as "rtsp: / / ~.mmt?pr=udp&pid=1". In this case, "rtsp" and "pr=tcp" identify it as MMTP / TCP distribution.

[0076] Furthermore, if the asset is distributed using the (D) MMTP / HTTP distribution protocol, "http: / / ~.mmt" is specified as the schema, and a parameter specifying the packet identifier (packet_id) is added in the query field. In this case, the URL is expressed as "http: / / ~.mmt?pr=pid=1". In this case, "http" and "mmt" identify it as an MMTP / HTTP distribution.

[0077] Additionally, if the asset is distributed using the (E)MPU / HTTP distribution protocol, the schema is specified as "http: / / ~.mp4". In other words, the URL in this case is expressed as "http: / / ~.mp4". In this case, the "http" and "mp4" identify it as MPU / HTTP distribution.

[0078] "Reception Sequence" Next, a description will be given of the reception sequence in the receiving terminal 200. First, (A) a case where an asset distributed using a multicast distribution protocol is received will be described with reference to Fig. 13. In the case of multicast distribution, a multicast server (MC server) exists.

[0079] The receiving terminal 200 receives a broadcast signal and acquires an MP table (MPT). From this MP table, the receiving terminal 200 obtains location information of assets distributed using a multicast distribution protocol. In this case, the location information includes a source address, a destination address, a destination port number, and a packet identifier. In this case, the receiving terminal 200 can identify that the distribution is multicast from the location type.

[0080] In this case, the receiving terminal 200 sends a JOIN message to the edge router, which includes the multicast address and port number included in the location information. When this JOIN message is sent, the multicast IP stream from the multicast server is sent to the receiving terminal 200 via the edge filter.

[0081] The receiving terminal 200 can extract the desired asset (component) from this multicast IP stream by filtering it with the packet identifier (Packet_id) included in the location information. When leaving this receiving state, the receiving terminal 200 sends a LEAVE message with the multicast address and port number attached to it to the edge router.

[0082] Next, referring to Figure 14, (B) the case of receiving an asset distributed using the MMTP / UDP distribution protocol will be described. In this MMTP / UDP distribution, the RTSP (Real Time Streaming Protocol) protocol is used. In this MMTP / UDP distribution, an RTSP server and an MMTP / UDP server exist. These servers may exist as separate devices or as the same device. In the illustrated example, they exist as the same device.

[0083] The receiving terminal 200 receives a broadcast signal and acquires an MP table (MPT). From this MP table, the receiving terminal 200 obtains location information for assets distributed using the MMTP / UDP distribution protocol. In this case, the location information is a URL, with "rtsp: / / ~.mmt" specified as the schema, and further parameters specifying UDP and a packet identifier are added in the query field. In this case, the receiving terminal 200 can identify that the distribution is MMTP / UDP based on "rtsp" and "pr=udp".

[0084] The receiving terminal 200 sends an RTSP request for "SETUP." At this time, the receiving terminal 200 inserts location information into the RTSP header. In this case, all of the location information obtained from the MP table is inserted as location information, or the parameter specifying the packet identifier is removed and inserted. This RTSP request is sent to the target server, and an "OK" response is returned from that server.

[0085] The receiving terminal 200 then sends an RTSP request for "PLAY." In response, an "OK" response is sent from the target server. At the same time, a transmission stream is sent from the MMTP / UDP server to the receiving terminal 200. The receiving terminal 200 can extract the target asset (component) from this stream by filtering using the packet identifier (Packet_id) included in the location information. When leaving this receiving state, the receiving terminal 200 sends an RTSP request for "TEARDOWN." In response, an "OK" response is sent from the server.

[0086] Next, with reference to Figure 15, we will describe the case of receiving assets distributed using the (C) MMTP / TCP distribution protocol. This MMTP / TCP distribution also uses the RTSP (Real Time Streaming Protocol) protocol. In this MMTP / TCP distribution, an RTSP server and an MMTP / TCP server exist. These servers may exist as separate devices or as the same device. The illustrated example shows the case where they exist as the same device.

[0087] The receiving terminal 200 receives a broadcast signal and acquires an MP table (MPT). From this MP table, the receiving terminal 200 obtains location information for assets distributed using the MMTP / TCP distribution protocol. In this case, the location information is a URL, with "rtsp: / / ~.mmt" specified as the schema, and further parameters specifying TCP and packet identifiers are added in the query field. In this case, the receiving terminal 200 can identify that the distribution is MMTP / TCP based on "rtsp" and "pr=tcp".

[0088] The receiving terminal 200 sends an RTSP request for "SETUP." At this time, the receiving terminal 200 inserts location information into the RTSP header. In this case, all of the location information obtained from the MP table is inserted as location information, or the parameter specifying the packet identifier is removed and inserted. This RTSP request is sent to the target server, and an "OK" response is returned from that server.

[0089] The receiving terminal 200 then sends an RTSP request for "PLAY." In response, an "OK" response is sent from the target server. At the same time, a transmission stream is sent from the MMTP / TCP server to the receiving terminal 200. The receiving terminal 200 can extract the target asset (component) from this stream by filtering using the packet identifier (Packet_id) included in the location information. When leaving this receiving state, the receiving terminal 200 sends an RTSP request for "TEARDOWN." In response, an "OK" response is sent from the server.

[0090] Next, referring to Figure 16, we will describe (D) receiving assets distributed using the MMTP / HTTP distribution protocol. In this MMTP / HTTP distribution, the HTTP (Hyper Text Transfer Protocol) protocol is used. In this MMTP / HTTP distribution, an HTTP server exists.

[0091] The receiving terminal 200 receives a broadcast signal and acquires an MP table (MPT). From this MP table, the receiving terminal 200 obtains location information for assets distributed using the MMTP / HTTP distribution protocol. In this case, the location information is a URL, with "http: / / ~.mmt" specified as the schema, and a parameter specifying a packet identifier (packet_id) added in the query field. The receiving terminal 200 can identify that the distribution is MMTP / HTTP based on "http" and "mmt."

[0092] The receiving terminal 200 sends an HTTP request to the HTTP server. At this time, the receiving terminal 200 inserts location information into the HTTP header. In this case, "http: / / ~.mmt" contained in the location information obtained from the MP table is inserted as the location information, and further, a parameter "pid=a" specifying a packet identifier and a parameter "msn=*" specifying an MPU sequence number are added in the query field. The parameter "msn=*" specifies "please send an MPU having an MPU sequence number for that timing."

[0093] This HTTP request is sent to the target HTTP server, and the HTTP server sends an MMTP stream containing an MPU with the MPU sequence number (=10) at the time the HTTP request was sent as an HTTP response to the receiving terminal 200. The receiving terminal 200 extracts the target asset (component) from this MMTP stream by filtering using the packet identifier (Packet_id) included in the location information.

[0094] After or before completing reception of the MMTP stream, the receiving terminal 200 sends an HTTP request to the HTTP server requesting the MPU with the next MPU sequence number (=11). The HTTP server then sends an MMTP stream including the MPU with the next MPU sequence number (=11) to the receiving terminal 200 as an HTTP response. The receiving terminal 200 can extract the desired asset (component) from this MMTP stream by filtering using the packet identifier (Packet_id) included in the location information.

[0095] Similarly, the receiving terminal 200 sends an HTTP request to the HTTP server requesting the MPU with the next MPU sequence number, receives an MMTP stream including the MPU with the next MPU sequence number as an HTTP response from the HTTP server, and extracts the desired asset (component) from the MMTP stream.

[0096] When making an HTTP request, the parameter "pid=a" included in the HTTP header specifies the type of asset, such as video or audio. Video and audio may be multiplexed into an MMTP stream. In such cases, the MPU sequence number will be the video MPU sequence number, and the audio MPU sequence number. Even if an MPU sequence number is specified, without the parameter "pid=a", it will not be clear which asset (component) the MPU sequence number belongs to.

[0097] 17 shows the process of cutting out an MMTP / HTTP multiplexed stream. When an HTTP request is received in which the parameter “pid=a” indicates a video and requests an MPU with MPU sequence number n, the HTTP server cuts out from the multiplexed stream the portion from when the video MPU sequence number switches from n-1 to n to when it switches from n to n+1, and sends this to the receiving terminal 200.

[0098] In this case, it may be necessary to extract audio from the same multiplexed stream. In this case, the receiving terminal 200 can recognize from the location information that audio is multiplexed with video. The receiving terminal 200 extracts the desired audio from the MMTP stream extracted using the video MPU sequence number by filtering using the packet identifier (Packet_id) included in the location information.

[0099] Next, referring to Fig. 18, (E) a case where an asset delivered using the MPU / HTTP delivery protocol is received will be described. In this MPU / HTTP delivery, the HTTP (Hyper Text Transfer Protocol) protocol is used. In this MPU / HTTP delivery, an HTTP server exists.

[0100] The receiving terminal 200 receives a broadcast signal and acquires an MP table (MPT). From this MP table, the receiving terminal 200 obtains location information for assets distributed using the MPU / HTTP distribution protocol. In this case, the location information is a URL, and "http: / / ~.mp4" is specified as the schema. The receiving terminal 200 can identify that the distribution is MPU / HTTP based on "http" and "mp4."

[0101] The receiving terminal 200 sends an HTTP request to the HTTP server. At this time, the receiving terminal 200 inserts location information into the HTTP header. In this case, "http: / / ~.mp4" contained in the location information obtained from the MP table is inserted as the location information, and the parameter "msn=*" specifying the MPU sequence number is added in the query field. The parameter "msn=*" specifies "please send the MPU at that timing."

[0102] This HTTP request is sent to the target HTTP server, and the HTTP server sends an MPU having the MPU sequence number (=10) at the time the HTTP request was sent to the receiving terminal 200 as an HTTP response.

[0103] After or before the completion of reception of the MPU, the receiving terminal 200 sends an HTTP request to the HTTP server requesting the MPU with the next MPU sequence number (=11).Then, the HTTP server sends the MPU with the next MPU sequence number (=11) to the receiving terminal 200 as an HTTP response.

[0104] Thereafter, in a similar manner, the receiving terminal 200 sends an HTTP request to the HTTP server requesting the MPU with the next MPU sequence number, and receives the MPU with the next MPU sequence number from the HTTP server as an HTTP response.

[0105] [Broadcast transmission system configuration] 19 shows an example of the configuration of a broadcast transmission system 100. This broadcast transmission system 100 has a signal transmission unit 101, a video encoder 102, an audio encoder 103, and a signaling generation unit 104. This broadcast transmission system 100 also has a TLV signaling generation unit 105, N IP service multiplexers 106-1 to 106-N, a TLV multiplexer 107, and a modulation / transmission unit 108.

[0106] Signal transmission unit 101 is, for example, a TV station studio or a recording / playback device such as a VTR, and transmits video and audio stream data to each encoder. Video encoder 102 encodes the video data transmitted from signal transmission unit 101, packetizes the data, and transmits IP packets containing video MMT packets to IP service multiplexer 106-1. Audio encoder 103 encodes the audio data transmitted from signal transmission unit 101, packetizes the data, and transmits IP packets containing audio MMT packets to IP service multiplexer 106-1.

[0107] The signaling generator 104 generates a signaling message and sends an IP packet containing an MMT packet with this signaling message placed in the payload to the IP service multiplexer 106-1. In this case, the signaling generator 104 places an MP table (MPT) in the PA message (see FIGS. 11 and 12). As described above, this MP table contains information on all assets (components) transmitted via broadcasting and communication. This information also includes location information for each asset.

[0108] The IP service multiplexer 106-1 performs time division multiplexing of the IP packets sent from each encoder. At this time, the IP service multiplexer 106-1 adds a TLV header to each IP packet to create a TLV packet. The IP service multiplexer 106-1 configures one channel portion to be placed in one transponder. The IP service multiplexers 106-2 to 106-N have the same function as the IP service multiplexer 106-1 and configure the other channel portions to be placed in that one transponder.

[0109] TLV signaling generator 105 generates signaling information and generates TLV packets that place this signaling information in the payload section. TLV multiplexer 107 multiplexes the TLV packets generated by IP service multiplexers 106-1 to 106-N and TLV signaling generator 105 to generate a broadcast stream. Modulation / transmission unit 108 performs RF modulation processing on the broadcast stream generated by TLV multiplexer 107 and sends it out to an RF transmission path.

[0110] The operation of the broadcast transmission system 100 shown in Fig. 19 will be briefly described. Video data transmitted from the signal transmission unit 101 is supplied to the video encoder 102. In this video encoder 102, the video data is encoded and further packetized to generate IP packets containing video MMT packets. These IP packets are sent to the IP service multiplexer 106-1. The same processing is also performed on the audio data transmitted from the signal transmission unit 101. Then, IP packets containing audio MMT packets generated by the audio encoder 103 are sent to the IP service multiplexer 106-1.

[0111] Furthermore, the signaling generator 104 generates a signaling message and generates an IP packet including an MMT packet with this signaling message placed in its payload. This IP packet is sent to the IP service multiplexer 106-1. At this time, an MP table (MPT) is placed in the PA message.

[0112] The IP service multiplexer 106-1 time-division multiplexes the IP packets sent from each encoder and signaling generator 104. At this time, a TLV header is added to each IP packet to form a TLV packet. This IP service multiplexer 106-1 processes one channel portion to be placed into one transponder, and the IP service multiplexers 106-2 to 106-N similarly process the other channel portions to be placed into that one transponder.

[0113] The TLV packets obtained by IP service multiplexers 106-1 to 106-N are sent to TLV multiplexer 107. This TLV multiplexer 107 also receives TLV packets from TLV signaling generator 105, in which signaling information is placed in the payload section.

[0114] TLV multiplexer 107 multiplexes the TLV packets generated by IP service multiplexers 106-1 to 106-N and TLV signaling generator 105 to generate a broadcast stream. This broadcast stream is sent to modulation / transmission unit 108. Modulation / transmission unit 108 performs RF modulation processing on this broadcast stream, and the RF modulated signal is sent to an RF transmission path as a broadcast signal.

[0115] [Configuration of receiving device] 20 shows an example of the configuration of a receiving terminal 200. This receiving terminal 200 has a CPU 201, a tuner / demodulator unit 202, a network interface unit 203, and a demultiplexer 204. This receiving terminal 200 also has a video decoder 205 and an audio decoder 206.

[0116] The CPU 201 constitutes a control unit and controls the operation of each unit of the receiving terminal 200. The tuner / demodulator 202 receives an RF modulated signal and performs demodulation processing to obtain a broadcast stream. The network interface 203 receives a transmission stream of a service distributed from the distribution server 300 via the communication network 400.

[0117] The demultiplexer 204 performs demultiplexing and depacketization processing on the broadcast stream obtained by the tuner / demodulation unit 202 and the transmission stream obtained by the network interface unit 203, and outputs signaling information, video and audio encoded data, etc.

[0118] The video decoder 205 decodes the coded video data obtained by the demultiplexer 204 to obtain baseband video data. The audio decoder 206 decodes the coded audio data obtained by the demultiplexer 204 to obtain baseband audio data.

[0119] The operation of receiving terminal 200 shown in Fig. 20 will be briefly described. Tuner / demodulation unit 202 receives an RF modulated signal transmitted via an RF transmission path, performs demodulation processing, and obtains a broadcast stream. This broadcast stream is sent to demultiplexer 204. Furthermore, network interface unit 203 receives a transmission stream of a service distributed from distribution server 300 via communication network 400, and sends it to demultiplexer 204.

[0120] The demultiplexer 204 performs demultiplexing and depacketizing processes on the broadcast stream from the tuner / demodulator 202 and the transmission stream from the network interface 203, extracting signaling information, video and audio coded data, and the like.

[0121] The various types of signaling information extracted by the demultiplexer 204 are sent to the CPU 201 via the CPU bus 207. This signaling information includes TLV-SI and MMT-SI. As described above, TLV-SI is a transmission control signal (TLV-NIT / AMT) carried on a TLV transmission packet, and MMT-SI is a signaling message as signaling information included in the payload portion of an MMT packet (see FIG. 2). The CPU 201 controls the operation of each unit of the receiving terminal 200 based on this signaling information.

[0122] The coded video data extracted by the demultiplexer 204 is sent to a video decoder 205 where it is decoded to obtain baseband video data, and the coded audio data extracted by the demultiplexer 204 is sent to an audio decoder 206 where it is decoded to obtain baseband audio data for audio output.

[0123] As described above, in the broadcasting and communication hybrid system 10 shown in Fig. 1, acquisition information including at least location information and protocol identification information is inserted into the MP table for assets (components) of the communication path. Therefore, the receiving side can successfully receive a transmission stream having transmission packets including components of the communication path based on this acquisition information.

[0124] In addition, in the broadcasting and communication hybrid system 10 shown in Fig. 1, packet identification information is included in the acquisition information of the asset (component) of the communication path inserted into the MP table. Therefore, even if the transmission packets of multiple assets are multiplexed in the MMTP stream, the receiving side can selectively acquire the desired transmission packet.

[0125] <2. Modifications> In the above-described embodiment, an example has been shown in which the transmission packets are MMT packets. However, the present technology is not limited to this, and it goes without saying that the present technology can also be applied to cases in which other similar transmission packets are handled.

[0126] The present technology can also be configured as follows. (1) a transmission stream generating unit that generates a transmission stream by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component; a transmitting unit that transmits the transmission stream through a predetermined transmission path; an information insertion unit that inserts, into the second transmission packet, acquisition information of a component of a communication path, the acquisition information including at least location information and protocol identification information; Transmitting device. (2) The above acquired information further includes packet identification information. The transmitting device according to (1) above. (3) The above protocol identification information is information for identifying at least one of the multicast delivery, MMTP / UDP delivery, MMTP / TCP delivery, MMTP / HTTP delivery, and MPU / HTTP delivery protocols. The transmitting device according to (1) or (2). (4) When the protocol identification information indicates that the above-mentioned MMTP / UDP distribution is to be performed, the above-mentioned acquisition information includes a parameter specifying UDP in addition to the URL. The transmitting device according to (3) above. (5) When the protocol identification information indicates that the MMTP / TCP distribution is to be performed, the acquisition information includes a parameter specifying TCP in addition to the URL. The transmitting device according to (3) above. (6) The above transmission packet is an MMT packet. The transmitting device according to any one of (1) to (5). (7) The predetermined transmission path is a broadcast transmission path. The transmitting device according to any one of (1) to (6). (8) a transmission stream generating step of generating a transmission stream by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component; a transmitting step of transmitting the transmission stream through a predetermined transmission path by a transmitting unit; an information insertion step of inserting, into the second transmission packet, acquisition information of a component of a communication path, the acquisition information including at least location information and protocol identification information; Sending method. (9) A receiving unit is provided for receiving a transmission stream obtained by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component through a predetermined transmission path, The second transmission packet contains acquisition information for a component of a communication path, the acquisition information including at least location information and protocol identification information; and a communication unit that receives a transmission stream having third transmission packets including a predetermined component from the server via a network in accordance with the protocol indicated by the protocol identification information by making a request to the server based on the location information and the protocol identification information; Receiving device. (10) The acquired information of the communication path component further includes packet identification information; The communication unit extracts the third transmission packet from the received transmission stream having the third transmission packet based on the packet identification information. The receiving device according to (9) above. (11) The protocol identification information is information for identifying at least one of multicast delivery, MMTP / UDP delivery, MMTP / TCP delivery, MMTP / HTTP delivery, and MPU / HTTP delivery. The receiving device according to (9) or (10) above. (12) When the above protocol identification information indicates the above MMTP / UDP distribution, The above acquired information includes parameters specifying UDP in addition to the URL, The communication unit is By making a request to a server using the URL and parameters specifying the UDP, a transmission stream having the third transmission packet is received from the server via a network using the MMTP / UDP delivery protocol. The receiving device according to (11) above. (13) When the above protocol identification information indicates that the above MMTP / TCP delivery is performed, The above acquired information includes parameters specifying TCP in addition to the URL, The communication unit is By making a request to a server using the URL and parameters specifying the TCP, a transmission stream having the third transmission packet is received from the server via a network using the MMTP / TCP delivery protocol. The receiving device according to (11) above. (14) When the above protocol identification information indicates that the delivery is MMTP / HTTP, The above acquired information includes a URL, The communication unit is By sequentially sending requests to a server using the above URL and parameters indicating the MPU sequence number, MMT packets including MPUs with MPU sequence numbers corresponding to the above parameters are sequentially received from the server via a network; The parameter indicating the MPU sequence number in the first request represents the MPU sequence number at the timing of the first request. The receiving device according to (11) above. (15) When the above protocol identification information indicates MPU / HTTP distribution, The above acquired information includes a URL, The communication unit is By sequentially sending requests to a server using the URL and parameters indicating the MPU sequence number, MPUs having MPU sequence numbers corresponding to the parameters are sequentially received from the server via a network; The parameter indicating the MPU sequence number in the first request represents the MPU sequence number at the timing of the first request. The receiving device according to (11) above. (16) The above transmission packet is an MMT packet. The receiving device according to any one of (9) to (15). (17) The predetermined transmission path is a broadcast transmission path. The receiving device according to any one of (9) to (16). (18) A receiving step of receiving, by a receiving unit, a transmission stream obtained by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component through a predetermined transmission path, The second transmission packet contains acquisition information for a component of a communication path, the acquisition information including at least location information and protocol identification information; and The method further includes a communication step of receiving, by a communication unit, a transmission stream having third transmission packets including a predetermined component through a network using a protocol indicated by the protocol identification information, based on the location information and the protocol identification information. Receiving method. (19) A receiving unit is provided for receiving a transmission stream obtained by time-division multiplexing a first transmission packet including a predetermined component and a second transmission packet including information about the predetermined component through a predetermined transmission path, The second transmission packet contains acquisition information for a component of a communication path, the acquisition information including at least location information and protocol identification information; and The transmission stream receiving unit further includes a processing unit for processing the transmission stream received by the receiving unit. Receiving device. [Explanation of symbols]

[0127] 10. Broadcasting and communication hybrid system 100···Broadcast transmission system 101 Signal sending unit 102 Video Encoder 103 Audio Encoder 104···Signaling generation section 105···TLV signaling generation unit 106-1 to 106-N IP Service Multiplexer 107 TLV Multiplexer 108 Modulation / Transmission Unit 200... Receiving terminal 201 CPU 202 Tuner / Demodulator 203 Network Interface Unit 204 Demultiplexer 205...Video decoder 206 Audio Decoder 207 CPU bus 300···Distribution server 400···Communication Network

Claims

1. a transmitting step of transmitting a transmission stream including a first MMT (MPEG Media Transport) protocol packet including a first component and a second MMT protocol packet including information about the first component; The second MMT protocol packet includes a URL (Uniform Resource Locator) as location information for acquiring the first component, and protocol identification information capable of specifying at least whether the first component is transmitted in an MMT protocol packet or by HTTP (Hyper Text Transfer Protocol). Sending method.

2. a transmitter that transmits a transmission stream that includes a first MMT (MPEG Media Transport) protocol packet that includes a first component and a second MMT protocol packet that includes information about the first component; The second MMT protocol packet includes a URL (Uniform Resource Locator) as location information for acquiring the first component, and protocol identification information capable of specifying at least whether the first component is transmitted in an MMT protocol packet or by HTTP (Hyper Text Transfer Protocol). Transmitting device.

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