Retransmission device and retransmission method

Abstract

To enable more appropriate processing of control information.SOLUTION: A conversion unit that converts first control information transmitted in a physical layer defined in a first broadcasting scheme that is a broadcasting scheme of terrestrial digital television broadcasting into second control information to be transmitted in an upper layer that is an upper layer of the physical layer defined in a second broadcasting scheme that is a broadcasting scheme of digital cable television broadcasting, in which the second broadcasting scheme employs an IP scheme, and the second control information is included in signaling information related to transmission control and is transmitted by a TLV packet, the signaling information being used in the second broadcasting scheme. The present disclosure is applicable to, for example, a retransmission device for retransmitting terrestrial digital television broadcasting.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a retransmission device and a retransmission method, and more particularly to a retransmission device and a retransmission method that are capable of more appropriately processing control information. [Background technology]

[0002] BACKGROUND ART Terrestrial digital television broadcasts are being retransmitted using digital cable television broadcasts and the like (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-220241 Summary of the Invention [Problem to be solved by the invention]

[0004] In terrestrial digital television broadcasting, it is possible to transmit control information via the physical layer, but when retransmission is performed using the transmodulation method, it has not been possible to properly process the control information transmitted via the physical layer. In addition, there is a demand for processing the control information transmitted via the physical layer on the receiving device side, and a proposal for properly processing the control information has been sought.

[0005] The present disclosure has been made in consideration of such circumstances, and makes it possible to process control information more appropriately. [Means for solving the problem]

[0006] A retransmission device according to one aspect of the present disclosure includes a receiving unit that receives a broadcast signal of a first broadcasting method, a conversion unit that converts first control information transmitted in a physical layer defined in the first broadcasting method into second control information transmitted in an upper layer that is a layer higher than the physical layer defined in a second broadcasting method that is different from the first broadcasting method, and a transmitting unit that transmits the broadcast signal of the second broadcasting method.

[0007] A retransmission method according to one aspect of the present disclosure is a retransmission method in which a retransmission device receives a broadcast signal of a first broadcasting method, converts first control information transmitted in a physical layer specified in the first broadcasting method into second control information transmitted in an upper layer that is a layer higher than the physical layer specified in a second broadcasting method different from the first broadcasting method, and transmits the broadcast signal of the second broadcasting method.

[0008] In a retransmission device and retransmission method according to one aspect of the present disclosure, a broadcast signal of a first broadcasting method is received, first control information transmitted in a physical layer defined in the first broadcasting method is converted into second control information transmitted in a higher layer that is a layer higher than the physical layer defined in a second broadcasting method different from the first broadcasting method, and the broadcast signal of the second broadcasting method is transmitted.

[0009] A receiving device according to one aspect of the present disclosure includes a receiving unit that receives and demodulates a broadcast signal of a first broadcasting system, and a processing unit that processes packets obtained by demodulating the broadcast signal, wherein the receiving unit has a conversion unit that converts first control information transmitted in a physical layer specified in the first broadcasting system into second control information transmitted in an upper layer that is a layer higher than the physical layer specified in a second broadcasting system different from the first broadcasting system, and the processing unit processes packets that store the second control information output from the receiving unit.

[0010] A receiving method according to one aspect of the present disclosure is a receiving method for a receiving device including a receiving unit that receives and demodulates a broadcast signal of a first broadcasting system, and a processing unit that processes packets obtained by demodulating the broadcast signal, wherein the receiving unit converts first control information transmitted in a physical layer specified in the first broadcasting system into second control information transmitted in an upper layer that is a layer higher than the physical layer specified in a second broadcasting system different from the first broadcasting system, and the processing unit processes packets that store the second control information output from the receiving unit.

[0011] In a receiving device and a receiving method according to one aspect of the present disclosure, a broadcast signal of a first broadcasting system is received and demodulated, packets obtained by demodulating the broadcast signal are processed, and first control information transmitted in a physical layer defined in the first broadcasting system is converted into second control information transmitted in an upper layer that is a layer higher than the physical layer and defined in a second broadcasting system different from the first broadcasting system, and packets storing the second control information are processed.

[0012] The retransmission device and the reception device according to one embodiment of the present disclosure may be independent devices or may be internal blocks constituting a single device. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram illustrating a configuration example of an embodiment of a transmission system to which the present disclosure is applied. [Figure 2] 2 is a block diagram showing an example of the configuration of the transmitting device of FIG. 1. FIG. [Figure 3] 2 is a block diagram showing an example of the configuration of the retransmission device of FIG. 1; [Figure 4] 2 is a block diagram showing an example of the configuration of the receiving device of FIG. 1. FIG. [Figure 5] FIG. 1 is a diagram illustrating an example of a protocol stack for terrestrial digital television broadcasting. [Figure 6] FIG. 10 is a diagram illustrating an example of the syntax of a TLV packet. [Figure 7]FIG. 10 is a diagram illustrating an example of packet type assignment. [Figure 8] A figure showing an example of TLV-SI syntax. [Figure 9] FIG. 10 is a diagram showing an example of table identification assignment of TLV-SI. [Figure 10] FIG. 10 is a diagram illustrating an example of a protocol stack at the time of retransmission by digital cable television broadcasting. [Figure 11] FIG. 10 is a diagram illustrating an example of the arrangement of a new control information descriptor. [Figure 12] FIG. 10 is a diagram illustrating a first example of the syntax of a control information descriptor defined by extending MMT-SI. [Figure 13] FIG. 10 is a diagram illustrating a second example of the syntax of a control information descriptor defined by extending MMT-SI. [Figure 14] FIG. 1 is a diagram illustrating an example of a protocol stack for an MPEG-2 system. [Figure 15] FIG. 10 is a diagram showing an example of the arrangement of descriptors in the MPEG-2 system. [Figure 16] FIG. 1 is a diagram illustrating an example of a protocol stack of ATSC 3.0. [Figure 17] FIG. 1 is a diagram showing an example of a table arrangement for ATSC 3.0. [Figure 18] 2 is a flowchart illustrating the flow of processing performed by each device in the transmission system of FIG. 1. [Figure 19] FIG. 10 is a block diagram illustrating another exemplary configuration of an embodiment of a transmission system to which the present disclosure is applied. [Figure 20] FIG. 20 is a block diagram showing an example of the configuration of the receiving device of FIG. 19. [Figure 21] 20 is a flowchart illustrating the flow of processing performed by each device in the transmission system of FIG. 19. [Figure 22] FIG. 1 is a block diagram illustrating an example of the configuration of a computer. DETAILED DESCRIPTION OF THE INVENTION

[0014] <1. First embodiment>

[0015] (Transmission system configuration) FIG. 1 is a block diagram showing an example of the configuration of an embodiment of a transmission system to which the present disclosure is applied.

[0016] In FIG. 1, the transmission system is made up of a transmitting device 10, a retransmitting device 20, and a receiving device 30.

[0017] The transmitting device 10 is a device that transmits content such as broadcast programs produced by terrestrial broadcasting stations. The transmitting device 10 generates a broadcast stream, performs necessary processing, and transmits the resulting terrestrial digital television broadcast signal from a transmitting antenna installed at a transmitting station.

[0018] The retransmission device 20 is a head-end device installed in a cable television station, etc. The retransmission device 20 performs necessary processing on the broadcast signal of the terrestrial digital television broadcast received via an antenna, and transmits the resulting broadcast signal of the digital cable television broadcast to the cable television transmission network.

[0019] The receiving device 30 is a fixed receiver such as a television receiver, a set-top box (STB), a recording device, a game console, a network storage, etc. The receiving device 30 is connected to a cable television transmission network by a cable such as an optical fiber cable or a coaxial cable.

[0020] The receiving device 30 receives a digital cable television broadcast signal transmitted from the retransmission device 20 via a cable television transmission network. The receiving device 30 processes a broadcast stream obtained from the broadcast signal to output video and audio of content such as a broadcast program, thereby allowing a user to view content such as a broadcast program.

[0021] In the following description, a broadcast signal for terrestrial digital television broadcasting will also be referred to as a terrestrial broadcast signal, and a broadcast signal for digital cable television broadcasting will also be referred to as a cable broadcast signal.

[0022] (Configuration of transmitting device) FIG. 2 is a block diagram showing an example of the configuration of the transmitting device 10 of FIG.

[0023] In FIG. 2, the transmission device 10 includes a generation unit 101 and a transmission unit 102.

[0024] The generating unit 101 generates a broadcast stream based on the data input thereto, and supplies it to the transmitting unit 102 .

[0025] A broadcast stream includes broadcast components that make up content such as broadcast programs and commercials produced by terrestrial broadcasting stations, as well as control information related to the broadcast components. The broadcast components include components such as video streams, audio streams, and subtitle streams.

[0026] The transmitting unit 102 generates a physical layer frame that conforms to the terrestrial digital television broadcasting standard based on the broadcast stream supplied from the generating unit 101. The transmitting unit 102 performs necessary processing, such as modulation, on the physical layer frame and transmits it as a terrestrial broadcast signal. The terrestrial broadcast signal is transmitted from a transmitting antenna installed at a transmitting station.

[0027] The physical layer frame includes control information such as transmission multiplexing control information. In the following description, control information transmitted in the physical layer is also referred to as physical layer control information. Control information transmitted in a higher layer (e.g., transport layer) that is a layer higher than the physical layer is also referred to as upper layer control information. For example, control information related to broadcast components is included in upper layer control information.

[0028] (Configuration of retransmission device) FIG. 3 is a block diagram showing an example of the configuration of the retransmission device 20 of FIG.

[0029] In FIG. 3, the retransmission device 20 comprises a receiving unit 201, a processing unit 202, and a transmitting unit 203.

[0030] The receiving unit 201 receives a terrestrial broadcast signal transmitted from the transmitting device 10 via an antenna, performs necessary processing on the signal, and supplies the processed signal to the processing unit 202 .

[0031] The processing unit 202 processes the signal supplied from the receiving unit 201 in accordance with the transmodulation method, and supplies the resulting signal to the transmitting unit 203. The transmodulation method is a method in which the retransmission device 20 of the cable television station changes the modulation method of the received broadcast signal and retransmits it.

[0032] The processing unit 202 has a conversion unit 211. The conversion unit 211 converts physical layer control information transmitted in a physical layer defined by the broadcasting method of terrestrial digital television broadcasting into upper layer control information transmitted in an upper layer defined by the broadcasting method of digital cable television broadcasting.

[0033] The transmitting unit 203 transmits the cable broadcasting signal based on the signal supplied from the processing unit 202. The cable broadcasting signal is transmitted via a cable television transmission network.

[0034] (Configuration of receiving device) FIG. 4 is a block diagram showing an example of the configuration of the receiving device 30 of FIG.

[0035] In FIG. 4, the receiving device 30 includes a receiving unit 301 and a processing unit 302 .

[0036] The receiving unit 301 is composed of a tuner, a demodulation LSI (Large Scale Integration), etc. The receiving unit 301 performs necessary processing such as demodulation on a cable broadcast signal received via a cable television transmission network, and supplies packets storing the resulting broadcast stream data to the processing unit 302.

[0037] The processing unit 302 is configured by a main SoC (System On Chip), etc. The processing unit 302 performs necessary processing such as decoding processing and playback processing on the packets supplied from the receiving unit 301.

[0038] A broadcast stream includes broadcast components and upper layer control information. The upper layer control information includes control information related to the broadcast components and control information obtained by converting physical layer control information transmitted in the physical layer specified in the broadcasting standard for terrestrial digital television broadcasting. For example, in the decoding and playback processes, the data of the broadcast components is decoded and played back based on the upper layer control information.

[0039] The video and audio data obtained through the decoding process, playback process, etc. is output to the subsequent circuit, whereby the receiving device 30 displays the video of the content such as a broadcast program on the display, and outputs the audio synchronized with the video from the speaker.

[0040] In the transmission system of Figure 1 configured as described above, the broadcast stream generated by the transmitting device 10 is retransmitted by the retransmission device 20, and is received and processed by the receiving device 30 via the cable television transmission network, making it possible to view content such as broadcast programs.

[0041] In the above-described configuration, the transmission device 10 includes the generation unit 101 and the transmission unit 102, but the generation unit 101 and the transmission unit 102 may be provided in separate devices. In other words, the transmission system may be configured as a transmission system including a device including the generation unit 101 and a device including the transmission unit 102.

[0042] In the above-described configuration, the retransmission device 20 has the receiving unit 201, the processing unit 202, and the transmitting unit 203, but the receiving unit 201, the processing unit 202, and the transmitting unit 203 may be provided in separate devices. Furthermore, in the above-described configuration, the case where there is one receiving device 30 is exemplified, but in reality, a plurality of receiving devices 30 are provided, and each is connected to a cable television transmission network.

[0043] (Broadcasting method details) In Japan, ISDB-T (Integrated Services Digital Broadcasting - Terrestrial) is currently used as the broadcasting standard for terrestrial digital television broadcasting, but next-generation terrestrial digital television broadcasting standards are currently under consideration. In next-generation terrestrial digital television broadcasting standards, control information will be transmitted along with the broadcast stream via multiple paths using TMCC (Transmission Multiplexing Configuration Control) and LLch (Low Latency Channel).

[0044] Figure 5 is a diagram showing an example of a protocol stack for next-generation terrestrial digital television broadcasting. In the protocol stack of Figure 5, terrestrial broadcasting, which is the lowest layer, corresponds to the physical layer, and TMCC and LLch are transmitted as physical layer control information. TMCC is transmission multiplex control information. LLch transmits additional information related to the broadcasting.

[0045] Next-generation terrestrial digital television broadcasting will use the IP (Internet Protocol) method, which uses TLV (Type Length Value) packets to transmit IP / UDP packets over broadcast transmission paths. IP / UDP packets are IP packets that contain UDP (User Datagram Protocol) packets. TLV packets are variable-length packets. When the IP method is used, the MMT (MPEG Media Transport) method can be used as the media transport method (transport protocol).

[0046] The MMT method is a method for transmitting multimedia content using a variety of networks, including broadcasting and communications. Using the MMT method, data such as video, audio, subtitles, control information, and applications are loaded into the MMTP (MMT Protocol) payload in a specified format, converted into MMTP packets, and stored in IP / UDP packets. The IP / UDP packets are then stored in TLV packets and encapsulated, and the resulting broadcast stream is transmitted as a terrestrial broadcast signal.

[0047] MMT-SI (Signaling Information) is control information that includes the configuration of a broadcast program. MMT-SI is upper layer control information that is transmitted in the upper layer, the transport layer. Note that IP / UDP packets can store and transmit data such as time information and content. The time information is information about time specified in a specific format such as the NTP (Network Time Protocol) format. Note that the MMT method is specified, for example, in Document A below.

[0048] Document A: ARIB STD-B60 1.6 Edition Association of Radio Industries and Businesses

[0049] It is anticipated that content such as broadcast programs broadcast on next-generation terrestrial digital television broadcasting will be retransmitted via digital cable television broadcasting. When retransmission via digital cable television broadcasting is performed using a transmodulation method, it is necessary to change the modulation method used for terrestrial digital television broadcasting to the modulation method used for digital cable television broadcasting.

[0050] When such retransmission is performed, there is no path to transmit the physical layer control information transmitted in the physical layer specified in the broadcasting system of terrestrial digital television broadcasting, and the control information cannot be transmitted properly.The broadcasting system of terrestrial digital television broadcasting and the broadcasting system of digital cable television broadcasting are standardized independently, so there is no agreement on a system that harmonizes them.

[0051] 1, in the retransmission device 20, the conversion unit 211 of the processing unit 202 converts the physical layer control information transmitted in the physical layer specified in the broadcasting format of terrestrial digital television broadcasting into upper layer control information transmitted in the upper layer specified in the broadcasting format of digital cable television broadcasting, thereby enabling the physical layer control information to be appropriately processed and transmitted. As a result, the receiving device 30 that receives digital cable television broadcasting can easily receive the upper layer control information converted from the physical layer control information transmitted in the physical layer specified in the broadcasting format of terrestrial digital television broadcasting, and can perform processing based on the upper layer control information.

[0052] The following describes in detail the conversion process performed by the conversion unit 211 of the processing unit 202 in the retransmission device 20. Here, five methods, a first method to a fifth method, are exemplified as the conversion process.

[0053] (First method) In the first method, by assigning control information to the packet type of the TLV packet, the retransmission device 20 converts the physical layer control information from the transmission device 10 into upper layer control information and transmits it to the reception device 30.

[0054] FIG. 6 is a diagram illustrating an example of the syntax of a TLV packet.

[0055] In FIG. 6, the TLV packet has a fixed value of '01111111' followed by an 8-bit packet_type and an 8-bit packet_length.

[0056] packet_type indicates the packet type that identifies the type of packet stored in the TLV, and packet_length indicates the length of the following data.

[0057] Figure 7 is a diagram showing an example of packet type assignment. As shown in Figure 7, when storing IPv4 packets and IPv6 packets, the packet type values ​​are '0x01' and '0x02'. Also, when storing header-compressed IP packets, transmission control signal packets, and null packets, the packet type values ​​are '0x03', '0xFE', and '0xFF'.

[0058] The values ​​'0x00', '0x04' to '0xFD' are undefined, but for example, '0x04' can be assigned to upper layer control information. This allows the upper layer control information to be encapsulated in a TLV packet identified by packet_type = '0x04'.

[0059] Returning to FIG. 6, when packet_type = '0x04', a 4-bit control_info_descriptor_tag and a 12-bit control_info_descriptor_length are placed.

[0060] The control_info_descriptor_tag indicates a tag that identifies the type of upper layer control information. The control_info_descriptor_length indicates the length of the data of the following upper layer control information.

[0061] The 8-bit control_info indicates that higher layer control information is allocated. This higher layer control information is control information that is the same as or corresponds to the physical layer control information. The higher layer control information can be various control information used in the processing of the receiving device 30.

[0062] As described above, when retransmission is performed by a broadcasting method that employs the IP method, upper layer control information is allocated to an undefined area of ​​the packet type in a TLV packet that includes an IP / UDP packet. This allows the retransmission device 20 to transmit the upper layer control information converted from the physical layer control information by the TLV packet.

[0063] (Second method) In the second method, TLV-SI (Signaling Information) is extended to assign control information to table identification, so that physical layer control information from the transmitting device 10 is converted into upper layer control information by the retransmitting device 20 and transmitted to the receiving device 30. TLV-SI is control information related to the multiplexing of IP packets. In other words, when the MMT method is used, two types of control information, MMT-SI and TLV-SI, are used.

[0064] FIG. 8 is a diagram illustrating an example of the syntax of TLV-SI.

[0065] In FIG. 8, the TLV-SI contains an 8-bit table_id, a 1-bit section_syntax_indicator, and fixed values ​​'1' and '11'.

[0066] The table_id indicates a table ID for identifying a table. The section_syntax_indicator indicates the value of the section syntax indicator.

[0067] Figure 9 is a diagram showing an example of allocation of table identifiers for TLV-SI. As shown in Figure 9, when TLV-NIT (own network) and TLV-NIT (other network) are placed, the table identifier values ​​are '0x40' and '0x41'. TLV-NIT (Network Information Table) is a table that contains information that associates transmission path information such as modulation frequency with broadcast programs in transmission by TLV packets. Note that TLV-NIT (own network) and TLV-NIT (other network) are determined by public notice.

[0068] 9, when an AMT is arranged, the value of the table identification is '0xFE'. The AMT (Address Map Table) is a table that contains information that associates a service identification that identifies a broadcast program number with an IP packet.

[0069] In table identification, values ​​other than '0x40', '0x41', and '0xFE' are undefined, but upper layer control information can be assigned to undefined values ​​such as '0xFD'. This allows upper layer control information to be included in a TLV-SI that includes a table identified by table_id = '0xFD', for example.

[0070] Returning to FIG. 8, following the fixed values ​​'1' and '11', a 12-bit section_length, a 4-bit control_info_descriptor_tag, and a 12-bit control_info_descriptor_length are arranged.

[0071] "section_length" indicates the length of the section, "control_info_descriptor_tag" indicates a tag that identifies the type of upper layer control information, and "control_info_descriptor_length" indicates the length of the data of the following upper layer control information.

[0072] The 8-bit control_info indicates that higher layer control information is allocated. This higher layer control information is control information that is the same as or corresponds to the physical layer control information. The higher layer control information can be various control information used in the processing of the receiving device 30.

[0073] As described above, when retransmission is performed by a broadcasting method that employs the IP method, the TLV-SI is extended and upper layer control information is assigned to the undefined area of ​​the table identification. This allows the retransmission device 20 to transmit the upper layer control information converted from the physical layer control information using a TLV packet with extended TLV-SI.

[0074] (Third method) In the third method, MMT-SI is extended to define a new control information descriptor, so that the retransmission device 20 converts physical layer control information from the transmission device 10 into upper layer control information and transmits it to the reception device 30.

[0075] FIG. 10 is a diagram showing an example of a protocol stack at the time of retransmission by digital cable television broadcasting.

[0076] The protocol stack in Fig. 10 differs from the protocol stack in Fig. 5 in the following respects. That is, in the protocol stack in Fig. 10, the broadcasting corresponding to the physical layer represents digital cable television broadcasting (cable broadcasting) rather than terrestrial digital television broadcasting (terrestrial broadcasting). When the transmodulation method is adopted for retransmission by digital cable television broadcasting, there is no appropriate path for transmitting physical layer control information such as TMCC or LLch, and therefore the physical layer control information is not shown.

[0077] In the protocol stack of Fig. 10, as shown in the area enclosed by box A1, MMT-SI is control information transmitted in the upper layer, the transport layer, and includes information such as the configuration of broadcast programs. Packets transmitted in the transport layer include IP / UDP packets and TLV packets. The protocol stack of Fig. 10 shows that physical layer control information is converted into upper layer control information, which is then encapsulated and transmitted using a new control information descriptor defined by extending MMT-SI.

[0078] Figure 11 is a diagram showing an example of the placement of a new control information descriptor. As shown in Figure 11, the new control information descriptor (Control_info_Descriptor) is defined in the MP table (MPT: MMT_Package_Table). The MP table provides information that constitutes a package, such as a list of assets and their locations on the network. Assets correspond to components such as video and audio that make up a package. The PA message (PA_Message) is used to transmit various tables. The PA message includes the MP table, is packetized as an MMTP packet, and is stored in an IP / UDP packet.

[0079] Fig. 12 is a diagram showing a first example of the syntax of a control information descriptor defined by extending MMT-SI. The syntax in Fig. 12 shows a case where a single piece of physical layer control information transmitted in the physical layer is transmitted in the transport layer as higher layer control information by MMT-SI.

[0080] The 16-bit descriptor_tag indicates a tag that identifies the type, and the 8-bit descriptor_length indicates the length of the following data.

[0081] The 4-bit control_info_descriptor_tag indicates a tag that identifies the type of the control information descriptor. The 12-bit control_info_descriptor_length indicates the length of the data of the following upper layer control information.

[0082] The 8-bit control_info indicates that higher layer control information is allocated. This higher layer control information is control information that is the same as or corresponds to the physical layer control information. The higher layer control information can be various control information used in the processing of the receiving device 30.

[0083] Fig. 13 is a diagram showing a second example of the syntax of a control information descriptor defined by extending MMT-SI. The syntax in Fig. 13 shows a case where multiple pieces of physical layer control information transmitted in the physical layer are transmitted in the transport layer as upper layer control information by MMT-SI.

[0084] In the syntax of FIG. 13, descriptor_tag and descriptor_length are arranged in the same manner as in the syntax of FIG.

[0085] The 8-bit num_of_control_info indicates the number of upper layer control information to be allocated. The 4-bit control_info_descriptor_tag indicates a tag that identifies the type of control information descriptor. The 12-bit control_info_descriptor_length indicates the length of the data of the following upper layer control information.

[0086] The 8-bit control_info indicates that higher layer control information is to be allocated. This higher layer control information is the same as or corresponds to the physical layer control information. The higher layer control information can be various control information used in processing by the receiving device 30, and the number of pieces of control information indicated by num_of_control_info can be allocated.

[0087] As described above, when retransmission is performed by a broadcasting method that employs the IP method and the MMT method as the media transport method, a new descriptor for transmitting arbitrary information is defined by extending MMT-SI, and upper layer control information is encapsulated using this descriptor. This enables the retransmission device 20 to transmit the upper layer control information converted from the physical layer control information using a TLV packet.

[0088] (Fourth method) The first to third methods described above have described configurations in which TLV packets are used as transmission packets and the MMT method is used as the media transport method when broadcast programs broadcast on next-generation terrestrial digital television broadcasting are retransmitted via digital cable television broadcasting.

[0089] In contrast, the fourth method describes a configuration using an MPEG-2 system when performing retransmission operations compatible with broadcasting methods such as DVB-C (Digital Video Broadcasting - Cable), DVB-C2 (J.382 method), and ISDB-T.

[0090] In the fourth method, when performing retransmission operations using the MPEG-2 system, a new control information descriptor is defined so that the retransmission device 20 converts physical layer control information from the transmission device 10 into upper layer control information and transmits it to the reception device 30.

[0091] Fig. 14 is a diagram showing an example of a protocol stack for an MPEG-2 system. In the protocol stack of Fig. 14, broadcasting corresponds to the physical layer, and TMCC is transmitted as physical layer control information. The broadcasting method compatible with the MPEG-2 system uses the MPEG2-TS (Transport Stream) method, and therefore TS packets are used. TS packets are fixed-length packets.

[0092] Data such as video, audio, and subtitles are packetized in PES (Packetized Elementary Stream) format and stored in TS packets. Control information such as PSI / SI (Program Specific Information / Service Information) and data for carousel transmission are stored in TS packets in section format. In the protocol stack of Fig. 14, as shown in the area enclosed by box A2, control information such as PSI / SI is transmitted in the upper layer, the transport layer.

[0093] Fig. 15 is a diagram showing an example of the arrangement of descriptors in the MPEG-2 system. As shown in Fig. 15, in the MPEG-2 system, control information descriptors can be stored in TS packets in section format and transmitted.

[0094] As described above, when retransmission is performed using a broadcasting method that employs the MPEG-2 system, a new descriptor that is transmitted in section format as an MPEG-2 system descriptor is defined, enabling placement of upper layer control information. This allows the retransmission device 20 to transmit the upper layer control information obtained by converting the physical layer control information, together with the control information related to the MPEG-2 system.

[0095] The PSI / SI transmitted in the MPEG-2 system is specified in, for example, the following document B.

[0096] Document B: ARIB STD-B10 5.13 Edition Association of Radio Industries and Businesses

[0097] (5th method) The first to third methods described above have described configurations in which TLV packets are used as transmission packets and the MMT method is used as the media transport method when broadcast programs broadcast on next-generation terrestrial digital television broadcasting are retransmitted via digital cable television broadcasting.

[0098] In contrast, the fifth method describes a configuration that uses the ROUTE method as a media transport method when performing retransmission operations in accordance with the ATSC3.0 (Advanced Television Systems Committee 3.0) broadcasting standard. The ROUTE (Real-Time Object Delivery over Unidirectional Transport) method uses a protocol that is an extension of FLUTE (File Delivery over Unidirectional Transport), a protocol suitable for unidirectional multicast transfer of binary files.

[0099] In the fifth method, when performing retransmission operations using ATSC 3.0, SLT and ROUTE-specific signaling are used so that the retransmission device 20 converts physical layer control information from the transmission device 10 into upper layer control information and transmits it to the reception device 30.

[0100] Figure 16 is a diagram showing an example of a protocol stack for ATSC3.0. In the protocol stack of Figure 16, broadcasting and communication correspond to the physical layer, and the protocol stack supports both broadcasting and communication transmission paths. In addition, in the protocol stack of Figure 16, when the physical layer is broadcasting, the protocol stack supports both the ROUTE method and the MMT method as media transport methods.

[0101] In the ROUTE method, video, audio, subtitles, and other data are processed as DASH segments defined by MPEG-DASH (Dynamic Adaptive Streaming over HTTP) and stored in IP / UDP packets, which are IP packets containing UDP packets. The IP / UDP packets are then stored and encapsulated in transmission packets, and the resulting broadcast stream is transmitted as a broadcast signal.

[0102] When the ROUTE method is used, control information such as an SLT (Service List Table) and ROUTE-specific signaling is used. The SLT is control information that includes information indicating the configuration of streams and services in a broadcasting network, such as information required for selecting a service. ROUTE-specific signaling is control information used in the ROUTE method. In the protocol stack of Fig. 16, as shown in the area surrounded by box A3, control information such as the SLT and ROUTE-specific signaling is transmitted in the transport layer, which is a higher layer.

[0103] Fig. 17 is a diagram showing an example of a table arrangement in ATSC 3.0. As shown in Fig. 17, ROUTE-specific signaling is a table in XML (Extensible Markup Language) format, and is associated with an SLT in XML format, so that control information related to the ROUTE method, such as the SLT and ROUTE-specific signaling, is used to transmit higher layer control information converted from physical layer control information.

[0104] As described above, when retransmission is performed using the ATSC3.0 broadcasting system that employs the ROUTE system as the media transport system, it is possible to arrange upper layer control information using control information related to the ROUTE system. This allows the retransmission device 20 to transmit the upper layer control information obtained by converting the physical layer control information, by including it in the control information related to the ROUTE system.

[0105] The SLT and ROUTE-specific signaling defined in ATSC3.0 are defined in, for example, the following document C.

[0106] Document C: ATSC Standard: Signaling, Delivery, Synchronization, and Error Protection (A / 331), Doc. A / 331:2019 20 June 2019

[0107] (Process flow) Next, the processing flow of each device in the transmission system of Fig. 1 will be described with reference to the flowchart of Fig. 18. Here, the explanation will be given taking as an example an operation in which a broadcast program broadcasted by terrestrial digital television broadcasting is retransmitted by digital cable television broadcasting.

[0108] First, a description will be given of the processes of steps S11 to S13 executed by the transmission device 10. In step S11, the generation unit 101 generates physical layer control information.

[0109] In step S12, the transmitter 102 generates a physical layer frame that conforms to the terrestrial digital television broadcasting standard. This physical layer frame includes physical layer control information. In step S13, the transmitter 102 transmits the physical layer frame as a terrestrial broadcast signal from a transmitting antenna installed at the transmitting station.

[0110] Next, a description will be given of the processes of steps S21 to S24 executed by the retransmission device 20. In step S21, the receiving unit 201 receives the terrestrial broadcast signal transmitted from the transmission device 10 via an antenna.

[0111] In step S22, the conversion unit 211 converts the physical layer control information transmitted in the physical layer specified in the broadcasting method for terrestrial digital television broadcasting into upper layer control information to be transmitted in the upper layer specified in the broadcasting method for digital cable television broadcasting, for example, using any of the first to third methods described above.

[0112] Here, when converting the control information, the conversion unit 211 may convert only the control information that matches a preset condition from among the physical layer control information into upper layer control information. For example, by setting region information obtained from the physical layer control information or the like as a condition, it is possible to convert only the control information corresponding to a specific region into upper layer control information. This allows only the necessary control information to be retransmitted, thereby reducing the amount of data to be transmitted.

[0113] In step S23, the processing unit 202 performs processing corresponding to the transmodulation method. In step S24, the transmitting unit 203 transmits the cable broadcasting signal to the cable television transmission network. This cable broadcasting signal includes, as upper layer control information, physical layer control information transmitted in the physical layer specified in the broadcasting method of terrestrial digital television broadcasting.

[0114] Next, a description will be given of the processes of steps S31 to S33 executed by the receiving device 30. In step S31, the receiving unit 301 receives a cable broadcast signal via a cable television transmission network.

[0115] In step S32, the receiving unit 301 performs necessary processing such as demodulation on the received cable broadcasting signal, and outputs a TLV packet storing the resulting upper layer control information.

[0116] In step S33, the processing unit 302 performs predetermined processing based on the upper layer control information output from the receiving unit 301. This upper layer control information is control information obtained by converting physical layer control information transmitted in the physical layer defined by the broadcasting system of terrestrial digital television broadcasting. The processing unit 302 also processes the broadcast stream, and decodes and plays back the data of the broadcast component based on the upper layer control information.

[0117] As described above, the retransmission device 20 converts the physical layer control information transmitted at the physical layer specified in the broadcasting method for terrestrial digital television broadcasting into upper layer control information transmitted at the upper layer specified in the broadcasting method for digital cable television broadcasting, thereby enabling the receiving device 30 to process the control information appropriately.

[0118] <2. Second embodiment>

[0119] (Transmission system configuration) FIG. 19 is a block diagram illustrating another exemplary configuration of an embodiment of a transmission system to which the present disclosure is applied.

[0120] In FIG. 19, the transmission system is made up of a transmitting device 10 and a receiving device 30A.

[0121] The transmitting device 10 generates a broadcast stream, performs necessary processing, and transmits the resulting terrestrial broadcast signal from a transmitting antenna installed at a transmitting station.

[0122] The receiving device 30A is a fixed receiver such as a television set. The receiving device 30A receives the terrestrial broadcast signal transmitted from the transmitting device 10 via an antenna. The receiving device 30A processes the broadcast stream obtained from the terrestrial broadcast signal to output video and audio of content such as a broadcast program. This allows the user to view content such as a broadcast program.

[0123] (Configuration of receiving device) FIG. 20 is a block diagram showing an example of the configuration of the receiving device 30A of FIG.

[0124] 20, the receiving device 30A includes a receiving unit 301A and a processing unit 302. The receiving unit 301A includes a conversion unit 311.

[0125] The receiving unit 301A is composed of a tuner, a demodulation LSI, etc. The receiving unit 301A performs necessary processing such as demodulation processing on the terrestrial broadcast signal received from the transmitting device 10 via the antenna, and supplies packets storing the resulting broadcast stream data to the processing unit 302.

[0126] The converter 311 is included in a demodulation device such as a demodulator LSI. The converter 311 converts physical layer control information transmitted in the physical layer defined by the broadcasting system of terrestrial digital television broadcasting into upper layer control information transmitted in an upper layer such as a transport layer. This upper layer control information is stored in a packet and supplied to the processor 302.

[0127] The processing unit 302 is configured from a main SoC, etc. The processing unit 302 performs necessary processing such as decoding processing and playback processing on the packets supplied from the receiving unit 301A.

[0128] A broadcast stream includes broadcast components and upper layer control information. The upper layer control information includes control information related to the broadcast components and control information obtained by converting physical layer control information transmitted in the physical layer specified in the broadcasting standard for terrestrial digital television broadcasting. For example, in the decoding and playback processes, the data of the broadcast components is decoded and played back based on the upper layer control information.

[0129] The video and audio data obtained through the decoding process, playback process, etc. is output to the subsequent circuit, whereby the receiving device 30A displays the video of the content such as a broadcast program on the display, and outputs the audio synchronized with the video from the speaker.

[0130] In the transmission system of Figure 19 configured as described above, in the receiving device 30A, the conversion unit 311 of the receiving section 301A converts physical layer control information transmitted in the physical layer specified in the broadcasting format of terrestrial digital television broadcasting transmitted from the transmitting device 10 into upper layer control information transmitted in an upper layer such as a transport layer, and outputs a packet including the upper layer control information to the processing unit 302 at the subsequent stage.

[0131] With this configuration, the receiving device 30A can multiplex and output upper layer control information obtained by converting physical layer control information transmitted in the physical layer defined by the broadcasting standard of terrestrial digital television broadcasting with data, without increasing the number of output signals of the demodulation device having the conversion unit 311. This allows the processing unit 302 made up of the main SoC to process the upper layer control information output from the receiving unit 301A including the demodulation device at an appropriate timing.

[0132] (Process flow) Next, the flow of processing by each device in the transmission system of FIG. 19 will be described with reference to the flowchart of FIG.

[0133] First, a description will be given of the processing of steps S111 to S113 executed by the transmitting device 10. In steps S111 to S113, similar to steps S11 to S13 in Fig. 18, a physical layer frame including physical layer control information is transmitted as a terrestrial broadcast signal from a transmitting antenna installed at a transmitting station.

[0134] Next, the processes of steps S131 to S134 executed by the receiving device 30A will be described. In step S131, the receiving unit 301A receives the terrestrial broadcast signal transmitted from the transmitting device 10 via the antenna.

[0135] In step S132, the conversion unit 311 converts physical layer control information transmitted in the physical layer defined in the broadcasting format of terrestrial digital television broadcasting into upper layer control information transmitted in an upper layer such as a transport layer, using, for example, any of the above-mentioned first to third formats. Note that the conversion unit 311 is not limited to any of the above-mentioned first to third formats, and may also use the above-mentioned fourth or fifth format.

[0136] In step S133, the receiving unit 301 outputs a TLV packet storing the upper layer control information. In step S134, the processing unit 302 performs predetermined processing based on the upper layer control information output from the receiving unit 301. This upper layer control information is control information obtained by converting physical layer control information transmitted in the physical layer specified in the broadcasting format of terrestrial digital television broadcasting. The processing unit 302 also processes the broadcast stream, and decodes and plays back the data of the broadcast component based on the upper layer control information.

[0137] As described above, in the receiving device 30A, the conversion unit 311 converts the physical layer control information transmitted in the physical layer specified in the broadcasting format of terrestrial digital television broadcasting into upper layer control information transmitted in an upper layer such as the transport layer, thereby enabling the processing unit 302 to process the control information appropriately.

[0138] <3. Modifications>

[0139] (Other broadcasting methods) In the above explanation, we have mainly described the operation of retransmitting content such as broadcast programs broadcast by next-generation terrestrial digital television broadcasting via digital cable television broadcasting, but it may also be applied to combinations of other broadcasting methods. For example, broadcasting methods such as satellite digital broadcasting using broadcasting satellites (BS) and communications satellites (CS) can be applied. Furthermore, the digital broadcasting method is not limited to ISDB, and broadcasting methods specified by DVB, ATSC, etc. may also be used in combination.

[0140] (Another example of a receiving device) In the above description, the receiving device 30 or the receiving device 30A is exemplified by devices capable of receiving broadcast signals, such as a television receiver or a set-top box, but the receiving device 30 or the receiving device 30A may have a communication function for performing communication via a communication line (communication network) such as the Internet or a telephone network. In this case, the receiving device 30 performs two-way communication with a server via a communication line such as the Internet.

[0141] In the above description, the receiving device 30 or the receiving device 30A has been described as being a fixed receiver such as a television receiver or a set-top box, but the receiving device 30 may also be a mobile receiver such as a smartphone, a mobile phone, or a tablet computer, or an in-vehicle receiver mounted in a vehicle such as an in-vehicle television. In this specification, a system refers to a logical collection of multiple devices.

[0142] (Name of descriptor, etc.) Other names may be used for the above-mentioned descriptors, fields, packets, streams, etc. For example, a TLV packet may be called an ALP (ATSC Link-layer Protocol) packet or a GSE (Generic Stream Encapsulation) packet. The difference between these names is a formal difference, and does not affect the actual content of the target descriptors, etc.

[0143] (Computer Configuration) The above-described series of processes can be executed by hardware or software. When the series of processes is executed by software, a program constituting the software is installed in a computer. Fig. 22 is a block diagram showing an example of the hardware configuration of a computer that executes the above-described series of processes by a program.

[0144] In the computer, a CPU (Central Processing Unit) 1001, a ROM (Read Only Memory) 1002, and a RAM (Random Access Memory) 1003 are interconnected by a bus 1004. An input / output interface 1005 is further connected to the bus 1004. An input unit 1006, an output unit 1007, a storage unit 1008, a communication unit 1009, and a drive 1010 are connected to the input / output interface 1005.

[0145] The input unit 1006 includes a keyboard, a mouse, a microphone, etc. The output unit 1007 includes a display, a speaker, etc. The storage unit 1008 includes a hard disk, a non-volatile memory, etc. The communication unit 1009 includes a network interface, etc. The drive 1010 drives a removable recording medium 1011 such as a semiconductor memory, a magnetic disk, an optical disk, or a magneto-optical disk.

[0146] In a computer configured as described above, the CPU 1001 loads a program recorded in the ROM 1002 or memory unit 1008 into the RAM 1003 via the input / output interface 1005 and the bus 1004 and executes it, thereby performing the above-mentioned series of processes.

[0147] The program executed by the computer (CPU 1001) can be provided by being recorded on a removable recording medium 1011 such as a package medium, for example. The program can also be provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital satellite broadcasting.

[0148] In a computer, the program can be installed in the storage unit 1008 via the input / output interface 1005 by inserting the removable recording medium 1011 into the drive 1010. The program can also be received by the communication unit 1009 via a wired or wireless transmission medium and installed in the storage unit 1008. Alternatively, the program can be installed in the ROM 1002 or the storage unit 1008 in advance.

[0149] Here, in this specification, the processing performed by a computer according to a program does not necessarily have to be performed chronologically in the order described in the flowchart. In other words, the processing performed by a computer according to a program also includes processing executed in parallel or individually (for example, parallel processing or object-based processing). Furthermore, the program may be processed by one computer (processor), or may be processed in a distributed manner by multiple computers.

[0150] It should be noted that the embodiments of the present disclosure are not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present disclosure. Furthermore, the effects described in this specification are merely examples and are not intended to be limiting, and other effects may also be obtained.

[0151] The present disclosure can also be configured as follows.

[0152] (1) a receiving unit that receives a broadcast signal in a first broadcasting system; a conversion unit that converts first control information transmitted in a physical layer defined in the first broadcasting system into second control information transmitted in an upper layer that is a layer higher than the physical layer defined in a second broadcasting system different from the first broadcasting system; a transmitting unit that transmits a broadcast signal of the second broadcasting system; A retransmission device comprising: (2) the first broadcasting system is a terrestrial digital television broadcasting system, The second broadcasting system is a digital cable television broadcasting system. The retransmission device according to (1) above. (3) The second broadcasting method is Adopting IP method, The MMT method is used as the media transport method. The second control information is Included in MMT-SI, It is transmitted by a TLV packet containing an IP / UDP packet storing the MMT-SI. The retransmission device according to (1) or (2) above. (4) The second broadcasting method employs an IP method, The second control information is It is stored in a TLV packet that contains an IP / UDP packet. Identified by the packet type of the TLV packet The retransmission device according to (1) or (2) above. (5) The second broadcasting method employs an IP method, The second control information is Included in TLV-SI, The TLV-SI is transmitted by an extended TLV packet. The retransmission device according to (1) or (2) above. (6) The second broadcasting method is A broadcasting system that complies with ATSC3.0, The ROUTE method is used as the media transport method. The second control information is included in the control information related to the ROUTE method. The retransmission device according to (1) above. (7) The second broadcasting system employs the MPEG-2 system, The second control information is included in the control information related to the MPEG-2 system. The retransmission device according to (1) or (2) above. (8) The conversion unit converts control information that matches a preset condition among the first control information into the second control information. The retransmission device according to any one of (1) to (7). (9) The upper layer is the transport layer The retransmission device according to any one of (1) to (8). (10) The retransmission device receiving a broadcast signal in a first broadcasting system; converting first control information transmitted in a physical layer defined in the first broadcasting system into second control information transmitted in an upper layer that is a layer higher than the physical layer defined in a second broadcasting system different from the first broadcasting system; Transmitting a broadcast signal of the second broadcasting system How to resend. (11) a receiving unit that receives and demodulates a broadcast signal of a first broadcasting system; a processing unit that processes packets obtained by demodulating the broadcast signal; Equipped with the receiving unit has a conversion unit that converts first control information transmitted in a physical layer defined in the first broadcasting system into second control information transmitted in an upper layer that is a layer higher than the physical layer defined in a second broadcasting system different from the first broadcasting system, The processing unit processes a packet that stores the second control information and is output from the receiving unit. Receiving device. (12) the first broadcasting system is a terrestrial digital television broadcasting system, The second broadcasting system is a digital cable television broadcasting system. The receiving device according to (11) above. (13) The second broadcasting method is Adopting IP method, The MMT method is used as the media transport method. The second control information is Included in MMT-SI, It is transmitted by a TLV packet containing an IP / UDP packet storing the MMT-SI. The receiving device according to (11) or (12). (14) The second broadcasting method employs an IP method, The second control information is It is stored in a TLV packet that contains an IP / UDP packet. Identified by the packet type of the TLV packet The receiving device according to (11) or (12). (15) The second broadcasting method employs an IP method, The second control information is Included in TLV-SI, It is transmitted by a TLV packet that stores the TLV-SI. The receiving device according to (11) or (12). (16) The second broadcasting method is A broadcasting system that complies with ATSC3.0, The ROUTE method is used as the media transport method. The second control information is included in the control information related to the ROUTE method. The receiving device according to (11) above. (17) The second broadcasting system employs the MPEG-2 system, The second control information is included in the control information related to the MPEG-2 system. The receiving device according to (11) or (12). (18) The conversion unit is included in a demodulation device. The receiving device according to any one of (11) to (17). (19) The upper layer is the transport layer The receiving device according to any one of (11) to (18). (20) a receiving unit that receives and demodulates a broadcast signal of a first broadcasting system; a processing unit that processes packets obtained by demodulating the broadcast signal; A receiving method for a receiving device comprising: the receiving unit converts first control information transmitted in a physical layer defined in the first broadcasting system into second control information transmitted in an upper layer that is a layer higher than the physical layer defined in a second broadcasting system different from the first broadcasting system; The processing unit processes a packet that stores the second control information and is output from the receiving unit. Receiving method. [Explanation of symbols]

[0153] 10 transmitting device, 20 retransmission device, 30 receiving device, 30A receiving device, 101 generating unit, 102 transmitting unit, 201 receiving unit, 202 processing unit, 203 transmitting unit, 211 converting unit, 301 receiving unit, 301A receiving unit, 302 processing unit, 311 converting unit, 1001 CPU

Claims

1. a conversion unit that converts first control information transmitted in a physical layer defined in a first broadcasting system that is a broadcasting system for terrestrial digital television broadcasting into second control information transmitted in an upper layer that is a layer higher than the physical layer defined in a second broadcasting system that is a broadcasting system for digital cable television broadcasting; The second broadcasting system employs an IP system, The second control information is Included in signaling information related to transmission control used in the second broadcasting system, Transmitted by TLV packets Re-sending device.

2. The second broadcasting system employs the MMT system as a media transport system, The second control information is Included in MMT-SI, It is transmitted by a TLV packet containing an IP / UDP packet storing the MMT-SI. The retransmission device according to claim 1 .

3. The second control information is Included in TLV-SI, The TLV-SI is transmitted by an extended TLV packet. The retransmission device according to claim 1 .

4. The conversion unit converts control information that matches a preset condition from among the first control information into the second control information. The retransmission device according to claim 1 .

5. The upper layer is the transport layer The retransmission device according to claim 1 .

6. The retransmission device converting first control information transmitted in a physical layer defined in a first broadcasting system, which is a broadcasting system for terrestrial digital television broadcasting, into second control information transmitted in an upper layer, which is a layer higher than the physical layer defined in a second broadcasting system, which is a broadcasting system for digital cable television broadcasting; The second broadcasting system employs an IP system, The second control information is Included in signaling information related to transmission control used in the second broadcasting system, Transmitted by TLV packets How to resend.

Images