Si retransmission method and si retransmission device

Abstract

To achieve excellent functionality for transmitting SI signals in a system that retransmits content of some channels of a plurality of channels.SOLUTION: An SI retransmission method in an SI retransmission device provided in a participating station that is capable of retransmitting content of some channels of content of a plurality of channels distributed by a common head-end station includes steps of: receiving an IP packet including a first SI signal of the plurality of channels; acquiring the first SI signal from the IP packet; performing a rewrite process to rewrite an NIT included in the first SI signal; and transmitting an IP packet including a second SI signal after the rewrite process.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to an SI retransmission method and an SI retransmission device. [Background technology]

[0002] So-called IP retransmission services, which deliver broadcast content to subscribers' homes in real time via an IP multicast network, have become popular. For example, Patent Document 1 (JP 2020-10199 A) discloses the following IP retransmission device. That is, the IP retransmission device is used in an IP retransmission system that retransmits multi-channel digital broadcast signals received from an antenna to multiple receivers via an IP multicast network. The IP retransmission device extracts SI information from the digital broadcast signals, stores the SI information in packets with SI identification values ​​added to part of the header information, and transmits the packets to the IP multicast network together with or separately from the broadcast stream. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-10199 Summary of the Invention [Problem to be solved by the invention]

[0004] With regard to transmission of SI (Service Information) signals in a system that retransmits content on some of multiple channels, a technology that can achieve superior functionality beyond that of the technology described in Patent Document 1 is desired.

[0005] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to provide an SI retransmission method and an SI retransmission device that can achieve excellent functionality regarding the transmission of SI signals in a system that retransmits content from some of multiple channels. [Means for solving the problem]

[0006] The SI retransmission method disclosed herein is an SI retransmission method in an SI retransmission device provided in a participating station that is capable of retransmitting content of some of the content of multiple channels distributed by a common headend station, and includes the steps of receiving an IP packet including a first SI signal, which is an SI signal of the multiple channels; acquiring the first SI signal from the received IP packet; performing a rewrite process to rewrite an NIT (Network Information Table) included in the acquired first SI signal; and transmitting an IP packet including a second SI signal, which is the SI signal after the rewrite process.

[0007] One aspect of the present disclosure can be realized not only as an SI retransmission method having such characteristic processing steps, but also as a program for causing a computer to execute such characteristic processing steps. Furthermore, one aspect of the present disclosure can be realized as a semiconductor integrated circuit that realizes part or all of an SI retransmission device, or as a system including an SI retransmission device. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to realize an excellent function for transmitting SI signals in a system that retransmits content on some of multiple channels. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating a configuration of a broadcasting system according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a diagram illustrating a configuration of an SI retransmission device according to the first embodiment of the present disclosure. [Figure 3] FIG. 3 is a flowchart defining an example of an operation procedure when the SI retransmission device according to the first embodiment of the present disclosure transmits the SI signal Sa2. [Figure 4] FIG. 4 is a diagram illustrating a configuration of a broadcasting system according to the second embodiment of the present disclosure. [Figure 5] FIG. 5 is a diagram illustrating a configuration of an SI retransmission device according to the second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] First, the contents of the embodiments of the present disclosure will be listed and described. (1) An SI retransmission method according to an embodiment of the present disclosure is an SI retransmission method in an SI retransmission device provided in a participating station that is capable of retransmitting content of some of the content of multiple channels distributed by a common headend station, and includes the steps of receiving an IP packet including a first SI signal, which is an SI signal of the multiple channels; acquiring the first SI signal from the received IP packet; performing a rewrite process to rewrite the NIT included in the acquired first SI signal; and transmitting an IP packet including a second SI signal, which is the SI signal after the rewrite process.

[0011] In this way, by rewriting the NIT included in the SI signal obtained from the received IP packet and transmitting the IP packet including the SI signal after the rewriting process, compared to a method in which the participating station generates a new SI signal based on EPG (Electronic Programming Guide) information or the like, the participating station can reuse the information included in the SI signal transmitted from the common headend station to transmit an SI signal including SI information related to the channel to be retransmitted. This simplifies the system configuration of the participating station and enables the transmission of SI signals at low cost. This therefore realizes excellent functionality for transmitting SI signals in a system that retransmits content from some of multiple channels.

[0012] (2) An SI retransmission device according to an embodiment of the present disclosure includes a receiving unit that receives an IP packet including a first SI signal, which is an SI signal of a plurality of channels; an acquiring unit that acquires the first SI signal from the IP packet received by the receiving unit; a processing unit that generates a second SI signal by rewriting the NIT included in the first SI signal acquired by the acquiring unit; and a transmitting unit that transmits an IP packet including the second SI signal generated by the processing unit.

[0013] In this way, by rewriting the NIT included in the first SI signals of multiple channels to generate and transmit the second SI signals, compared to a configuration in which the SI retransmission device generates a new SI signal based on EPG information or the like, it is possible to reuse information included in the first SI signals transmitted from other broadcast stations to transmit the second SI signals including SI information related to the channel to be retransmitted. This simplifies the system configuration of the broadcast station in which the SI retransmission device is installed, and enables SI signals to be transmitted at low cost. This makes it possible to achieve excellent functionality for transmitting SI signals in a system that retransmits content from some of multiple channels.

[0014] (3) In (2) above, the NIT may include tuning information for the plurality of channels, and the processing unit may generate the second SI signal by rewriting the tuning information in the NIT included in the first SI signal.

[0015] With this configuration, the NIT channel selection information can be rewritten to match the channel to be retransmitted and the SI signal can be sent out, so that users can select from among the channels that can be viewed at their homes within the distribution area of ​​the broadcasting station where the SI retransmission device is installed.

[0016] (4) In the above (3), the processing unit may generate the second SI signal, which is an SI signal of some of the channels among the plurality of channels, by deleting information of some of the channels in the channel selection information.

[0017] With this configuration, channels that cannot be viewed in the distribution area of ​​the broadcasting station where the SI retransmission device is installed can be excluded from the channel selection targets of the user.

[0018] (5) In the above (3) or (4), the processing unit may add information about a channel different from the plurality of channels to the channel selection information.

[0019] With this configuration, when a broadcasting station in which an SI retransmission device is installed further distributes content of an independent broadcasting channel, the independent broadcasting channel can be included in the channel selection targets of a user.

[0020] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, identical or corresponding parts are designated by the same reference numerals, and their description will not be repeated. Furthermore, at least some of the embodiments described below may be combined in any manner.

[0021] First Embodiment [Configuration and basic operation] Fig. 1 is a diagram showing the configuration of a broadcasting system according to a first embodiment of the present disclosure. Referring to Fig. 1, a broadcasting system 401 includes an SI retransmission device 101, a switch 111, an SI sending device 201, IP broadcasting devices 211A, 211B, and 211C that are IP broadcasting devices 211, and hubs 121 and 221. The SI sending device 201, IP broadcasting device 211, and hub 221 are provided in a common headend station 251. The SI retransmission device 101, the switch 111, and the hub 121 are provided in a participating station 151. The IP broadcasting devices 211A, 211B, and 211C are assigned channels ch1, ch2, and ch3, respectively.

[0022] The broadcasting system 401 may be configured to include two or four or more IP broadcasting devices 211. The broadcasting system 401 may also be configured to include multiple sets of SI retransmission devices 101, switches 111, and hubs 121, each set being provided in a plurality of participating stations 151.

[0023] (Joint Headend Station) The common headend station 251 distributes content for multiple services, i.e., channels. The content includes, for example, audio information, video information, PSI (Program Specific Information), and SI information. As an example, the common headend station 251 distributes content for channels ch1, ch2, and ch3 to STBs (Set Top Boxes) 301A installed in subscriber homes within a distribution area RA.

[0024] More specifically, the SI sending device 201 in the common headend station 251 receives EPG information for channels ch1, ch2, and ch3 from a control device not shown, and generates multiple TS packets containing SI information for channels ch1, ch2, and ch3 based on the received EPG information.

[0025] The TS packets generated by the SI sending device 201 contain table information such as an NIT, an SDT (Service Description Table), and an EIT (Event Information Table) as SI information.

[0026] The NIT stored in the TS packet generated by the SI sending device 201 includes tuning information for channels ch1, ch2, and ch3. For example, the NIT includes, as tuning information, information necessary for tuning channels ch1, ch2, and ch3, such as a service ID.

[0027] The SI sending device 201 transmits an SI signal Sa1, which is a stream of channels ch1, ch2, and ch3, including the generated TS packets, to the STB 301A. More specifically, the SI sending device 201 transmits a plurality of IP packets Pa1 including the SI signal Sa1 to the STB 301A via the hub 221 and the IP network 311A. The SI sending device 201 also transmits the IP packets Pa1 to the participating station 151 via the hub 221. The SI signal Sa1 is a signal dedicated to SI for transmitting SI information, and is an example of a first SI signal. The destination address of the IP packet Pa1 is set to a predetermined multicast address for SI transmission. The SI sending device 201 also transmits a plurality of IP packets including the SI signal Sa1 to the IP broadcasting device 211.

[0028] Each IP broadcasting device 211 receives IP packets from the SI sending device 201 and acquires an SI signal Sa1 from the received IP packets. Each IP broadcasting device 211 also receives IP packets containing audio and video information from a distribution device (not shown) at the program distribution provider and acquires the audio and video information from the received IP packets. Each IP broadcasting device 211 also generates PSI information for channels ch1, ch2, and ch3.

[0029] Based on the acquired SI signal Sa1, audio information, and video information, and the generated PSI information, the IP broadcast device 211 generates a plurality of TS packets containing the content of the channel assigned to the IP broadcast device 211. The TS packets generated by the IP broadcast device 211 contain audio information, video information, a PAT (Program Association Table), etc., but do not contain an NIT. The IP broadcast device 211 transmits a broadcast signal Sb, which is a stream containing the generated TS packets, to the STB 301A.

[0030] More specifically, the IP broadcast device 211A transmits a plurality of IP packets Pb1, including a broadcast signal Sb1, as the broadcast signal Sb to the STB 301A via the hub 221 and the IP network 311A. The IP broadcast device 211A also transmits the IP packets Pb1 to the participating station 151 via the hub 221. The destination address of the IP packets Pb1 is set to a predetermined multicast address corresponding to the channel Ch1.

[0031] The IP broadcast device 211B transmits a plurality of IP packets Pb2 including the broadcast signal Sb2 as the broadcast signal Sb to the STB 301A via the hub 221 and the IP network 311A. The IP broadcast device 211B also transmits the IP packets Pb2 to the participating station 151 via the hub 221. The destination address of the IP packets Pb2 is set to a predetermined multicast address corresponding to the channel Ch2.

[0032] The IP broadcast device 211C transmits a plurality of IP packets Pb3, including the broadcast signal Sb3, as the broadcast signal Sb to the STB 301A via the hub 221 and the IP network 311A. The IP broadcast device 211C also transmits the IP packets Pb3 to the participating station 151 via the hub 221. The destination address of the IP packets Pb3 is set to a predetermined multicast address corresponding to the channel Ch3.

[0033] The STB 301A receives a plurality of IP packets Pa1 from the SI sending device 201 via the hub 221 and the IP network 311A, and can select channels ch1, ch2, and ch3 based on the NIT contained in the received IP packets Pa1.

[0034] (Participating stations) Participating station 151 can retransmit the content of some of the channels ch1, ch2, and ch3 distributed by common headend station 251. For example, participating station 151 retransmits the content of channels ch1 and ch2 to STB 301B installed in a subscriber's home in distribution area RB.

[0035] More specifically, switch 111 receives IP packets Pb1, Pb2, and Pb3 from IP broadcast device 211 via hub 221. Of the received IP packets Pb1, Pb2, and Pb3, switch 111 transmits IP packets Pb1 and Pb2 to STB 301B via hub 121 and IP network 311B. Meanwhile, switch 111 discards the received IP packet Pb3. Unlike a system in which a broadcast signal is distributed via RF (Radio Frequency) from a common headend station, broadcast system 401 distributes a broadcast signal Sb that does not include an NIT via IP from common headend station 251. Therefore, there is no need to install a device that processes broadcast signal Sb in participating stations; instead, it is sufficient to install switch 111 and SI retransmission device 101 in participating stations 151, simplifying the system configuration of participating stations.

[0036] The SI retransmission device 101 receives an IP packet Pa1 from the SI transmission device 201 via the hub 221. The SI retransmission device 101 acquires an SI signal Sa1 from the received IP packet Pa1 and generates an SI signal Sa2 by rewriting the NIT included in the acquired SI signal Sa1. The SI signal Sa2 is a signal dedicated to SI for transmitting SI information, and is an example of a second SI signal.

[0037] The SI retransmission device 101 transmits the generated SI signal Sa2 to the STB 301B. More specifically, the SI retransmission device 101 transmits a plurality of IP packets Pa2 including the SI signal Sa2 to the STB 301B via the hub 121 and the IP network 311B. The destination address of the IP packets Pa2 is set to a predetermined multicast address for sending SI.

[0038] (SI retransmission device) 2 is a diagram illustrating a configuration of an SI retransmission device according to the first embodiment of the present disclosure. Referring to FIG. 2, the SI retransmission device 101 includes an IP receiving unit 10, a processing unit 20, and an IP transmitting unit 30. The processing unit 20 includes a packet filter 21, an NIT generating unit 22, and a multiplexing unit 23. The IP receiving unit 10 is an example of a receiving unit and an example of an acquiring unit. The IP transmitting unit 30 is an example of a transmitting unit. Some or all of the IP receiving unit 10, the processing unit 20, and the IP transmitting unit 30 are realized by, for example, a processing circuit including one or more processors.

[0039] The IP receiver 10 receives the IP packet Pa1 including the SI signal Sa1. The IP receiver 10 acquires the SI signal Sa1 from the received IP packet Pa1. More specifically, the IP receiver 10 receives the IP packet Pa1 from the SI sending device 201 via the hub 221, and acquires the SI signal Sa1 from the received IP packet Pa1. The IP receiver 10 outputs the acquired SI signal Sa1 to the processing unit 20.

[0040] The processing unit 20 generates the SI signal Sa2 by performing a rewriting process to rewrite the NIT included in the SI signal Sa1 acquired by the IP receiving unit 10. In the rewriting process, the processing unit 20 rewrites the channel selection information of the NIT included in the SI signal Sa1. For example, the processing unit 20 deletes the information about channel ch3 from the channel selection information of the NIT included in the SI signal Sa1.

[0041] The packet filter 21 receives the SI signal Sa1 from the IP receiver 10. The packet filter 21 performs a removal process to remove TS packets containing NIT from the received SI signal Sa1. Here, the PID (Packet ID) of the TS packet containing NIT is "0x0010." A number beginning with "0x" means that the numbers following "0x" are expressed in hexadecimal.

[0042] In the removal process, the packet filter 21 refers to the header portion of the TS packet included in the SI signal Sa1 received from the IP receiver 10, and removes from the SI signal Sa1 TS packets having a PID of "0x0010" among the TS packets included in the SI signal Sa1. The packet filter 21 outputs the SI signal Sa1 after the removal process, from which TS packets including NITs have been removed, to the multiplexer 23.

[0043] The NIT generation unit 22 generates an NIT to be sent to the STB 301B. For example, the NIT generation unit 22 receives the SI signal Sa1 from the IP reception unit 10 and extracts TS packets including an NIT from the received SI signal Sa1. More specifically, the NIT generation unit 22 references the header portions of the TS packets included in the SI signal Sa1 received from the IP reception unit 10 and extracts TS packets having a PID of "0x0010" from the TS packets included in the SI signal Sa1.

[0044] The NIT generation unit 22 acquires the NIT from the extracted TP packet, and performs a deletion process to delete information necessary for selecting channel ch3, such as the service ID of channel ch3, from the channel selection information of the acquired NIT.The NIT generation unit 22 then generates a TS packet including the NIT after the deletion process, and outputs the generated TS packet to the multiplexing unit 23.

[0045] The multiplexing unit 23 generates an SI signal Sa2, which is a stream in which the TS packets generated by the NIT generation unit 22 are multiplexed onto the SI signal Sa1 that has been subjected to the removal process by the packet filter 21. More specifically, the multiplexing unit 23 generates the SI signal Sa2 by multiplexing, in the time axis direction, the SI signal Sa1 received from the packet filter 21 and the TS packets received from the NIT generation unit 22. The multiplexing unit 23 outputs the generated SI signal Sa2 to the IP transmission unit 30.

[0046] The IP transmitting unit 30 transmits the IP packet Pa2 including the SI signal Sa2 after the rewriting process by the processing unit 20. More specifically, the IP transmitting unit 30 receives the SI signal Sa2 from the multiplexing unit 23, and transmits the plurality of IP packets Pa2 including the received SI signal Sa2 to the STB 301B via the hub 121 and the IP network 311B.

[0047] STB301B receives multiple IP packets Pa2 from SI retransmission device 101 via hub 121 and IP network 311B, and can select channels ch1 and ch2 out of channels ch1, ch2, and ch3 based on the NIT contained in the received IP packets Pa2.

[0048] [Operation flow] FIG. 3 is a flowchart defining an example of an operation procedure when the SI retransmission device according to the first embodiment of the present disclosure transmits the SI signal Sa2.

[0049] Referring to FIG. 3, first, the SI retransmission device 101 receives the IP packet Pa1 from the SI transmission device 201 via the hub 221 (step S11).

[0050] Next, the SI retransmission device 101 acquires the SI signal Sa1 from the received IP packet Pa1 (step S12).

[0051] Next, the SI retransmission device 101 performs a rewriting process to rewrite the NIT included in the SI signal Sa1. More specifically, the SI retransmission device 101 performs a removal process to remove TS packets including the NIT from the SI signal Sa1, and generates the SI signal Sa2 by multiplexing TS packets including the NIT, from which information necessary for selecting channel ch3 has been deleted, onto the SI signal Sa1 after the removal process (step S13).

[0052] Next, the SI retransmission device 101 transmits the generated IP packet Pa2 including the SI signal Sa2 to the STB 301B via the hub 121 and the IP network 311B (step S14).

[0053] In the SI retransmission device 101 according to the first embodiment of the present disclosure, the processing unit 20 is configured to rewrite the tuning information of the NIT included in the SI signal Sa1 in the rewriting process, but this is not limiting. The processing unit 20 may be configured to rewrite information other than the tuning information in the NIT in the rewriting process.

[0054] Furthermore, in the SI retransmission device 101 according to the first embodiment of the present disclosure, the NIT generation unit 22 in the processing unit 20 is configured to extract TS packets containing an NIT from the SI signal Sa1, acquire the NIT from the extracted TS packets, and perform a deletion process to delete information necessary for tuning to channel ch3 from the tuning information in the acquired NIT, but this is not limited to this.The NIT generation unit 22 may be configured to generate tuning information for channels ch1 and ch2 and generate an NIT containing the generated tuning information, instead of extracting and deleting TS packets containing an NIT.

[0055] Furthermore, in the broadcasting system 401 according to the first embodiment of the present disclosure, the SI sending device 201 is configured to send a plurality of IP packets including the SI signal Sa1 to the IP broadcasting device 211, but this is not limiting. The SI sending device 201 may be configured not to send the IP packet including the SI signal Sa1 to the IP broadcasting device 211 when the IP broadcasting device 211 receives an IP packet further including EPG information from a distribution device.

[0056] Furthermore, in broadcasting system 401 according to the first embodiment of the present disclosure, common headend station 251 is configured to distribute content on channels ch1, ch2, and ch3 to STB 301A, but this is not limited to this. Common headend station 251 may be configured not to distribute content on a channel among channels ch1, ch2, and ch3 that is retransmitted by participating station 151, such as channel ch2. In this case, IP broadcasting device 211B transmits IP packet Pb2 to participating station 151 via hub 221, but does not transmit IP packet Pb2 to STB 301A.

[0057] Next, other embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals and their description will not be repeated.

[0058] <Second embodiment> [Configuration and basic operation] This embodiment relates to a broadcasting system 402 that is capable of transmitting content for an independent broadcasting channel in addition to the broadcasting system 401 according to the first embodiment. Except for the details described below, the broadcasting system 402 is the same as the broadcasting system 401 according to the first embodiment.

[0059] 4 is a diagram showing the configuration of a broadcasting system according to a second embodiment of the present disclosure. Referring to FIG. 4, compared to broadcasting system 401, broadcasting system 402 includes an SI retransmission device 102 instead of SI retransmission device 101, and further includes an IP broadcasting device 112. SI retransmission device 102, IP broadcasting device 112, switch 111, and hub 121 are provided in participating station 152. An independent broadcasting channel ch5, different from channels ch1, ch2, and ch3, is assigned to IP broadcasting device 112.

[0060] In comparison with participating station 151, participating station 152 not only retransmits the content of channels ch1 and ch2, but also distributes the content of its own broadcast channel ch5 to STB 301B.

[0061] More specifically, compared to the SI retransmission device 101, the SI retransmission device 102 generates an SI signal Sa3 that further includes SI information for channel ch5. The SI signal Sa3 is a signal dedicated to SI for transmitting SI information, and is an example of a second SI signal. The SI retransmission device 102 transmits multiple IP packets Pa3 including the generated SI signal Sa3 to the STB 301B via the hub 121 and the IP network 311B. The destination address of the IP packet Pa3 is set to a predetermined multicast address for SI transmission. The SI retransmission device 102 also transmits multiple IP packets including the SI signal Sa3 to the IP broadcasting device 112.

[0062] The IP broadcasting device 112 receives IP packets from the SI retransmission device 102 and acquires the SI signal Sa3 from the received IP packets. The IP broadcasting device 112 also acquires audio information and video information from a storage unit inside or outside the IP broadcasting device 112 and encodes the acquired audio information and video information. The IP broadcasting device 112 also generates PSI information for channel ch5.

[0063] The IP broadcast device 112 generates multiple TS packets containing the content of channel ch5 based on the acquired SI signal Sa3, the encoded audio and video information, and the generated PSI information. The TS packets generated by the IP broadcast device 112 contain audio information, video information, a PAT, and the like, but do not contain an NIT. The IP broadcast device 112 transmits a broadcast signal Sb, which is a stream containing the generated TS packets, to the STB 301B. More specifically, the IP broadcast device 112 transmits multiple IP packets Pb5 containing a broadcast signal Sb5 as the broadcast signal Sb to the STB 301B via the hub 121 and the IP network 311B. The destination address of the IP packets Pb5 is set to a predetermined multicast address corresponding to channel Ch5.

[0064] (SI retransmission device) 5 is a diagram illustrating a configuration of an SI retransmission device according to a second embodiment of the present disclosure. Referring to FIG. 5, compared to the SI retransmission device 101, the SI retransmission device 102 includes a processing unit 40 instead of the processing unit 20. The processing unit 40 includes a packet filter 41, an NIT generation unit 42, an SDT extraction unit 43, an SDT generation unit 44, an SDT synthesis unit 45, an EIT extraction unit 46, an EIT generation unit 47, an EIT synthesis unit 48, and a multiplexing unit 49.

[0065] The IP receiver 10 receives the IP packet Pa1 from the SI transmitter 201 via the hub 221, and acquires the SI signal Sa1 from the received IP packet Pa1. The IP receiver 10 outputs the acquired SI signal Sa1 to the processor 40.

[0066] The processing unit 40 performs a rewriting process to rewrite the NIT included in the SI signal Sa1 acquired by the IP receiving unit 10. For example, the processing unit 40 deletes information about channel ch3 from the tuning information of the NIT included in the SI signal Sa1, and adds information about channel ch5 to the tuning information.

[0067] The packet filter 41 receives the SI signal Sa1 from the IP receiver 10. The packet filter 41 performs a removal process to remove TS packets containing an NIT, TS packets containing an SDT, and TS packets containing an EIT from the received SI signal Sa1. Here, the PID of the TS packets containing an SDT is "0x0011," and the PID of the TS packets containing an EIT is "0x0012."

[0068] In the removal process, the packet filter 41 refers to the header portions of the TS packets included in the SI signal Sa1 received from the IP receiver 10, and removes from the SI signal Sa1, TS packets with a PID of "0x0010," TS packets with a PID of "0x0011," and TS packets with a PID of "0x0012" from the TS packets included in the SI signal Sa1. The packet filter 41 outputs the SI signal Sa1 after the removal process to the multiplexer 49.

[0069] The NIT generation unit 42 generates an NIT to be sent to the STB 301 B. For example, the NIT generation unit 42 receives the SI signal Sa1 from the IP reception unit 10, and extracts TS packets including the NIT from the received SI signal Sa1.

[0070] The NIT generation unit 42 acquires the NIT from the extracted TP packet, and performs modification processing to delete information necessary for selecting channel ch3 from the tuning information of the acquired NIT, and add information necessary for selecting channel ch5 to the tuning information. The NIT generation unit 42 then generates a TS packet including the NIT after the modification processing, and outputs the generated TS packet to the multiplexing unit 49.

[0071] The SDT extraction unit 43 receives the SI signal Sa1 from the IP reception unit 10 and extracts TS packets containing an SDT from the received SI signal Sa1. More specifically, the SDT extraction unit 43 references the headers of the TS packets included in the SI signal Sa1 received from the IP reception unit 10 and extracts TS packets with a PID of "0x0011" from among the TS packets included in the SI signal Sa1. The SDT extraction unit 43 generates section data of the SDT by combining the data stored in the payloads of the extracted TS packets. The SDT extraction unit 43 outputs the generated section data to the SDT synthesis unit 45.

[0072] The SDT generation unit 44 receives EPG information for channel ch5 from a control device (not shown), and based on the received EPG information, generates section data of the SDT for channel ch5. The SDT generation unit 44 outputs the generated section data to the SDT synthesis unit 45.

[0073] The SDT synthesis unit 45 multiplexes the SDT section data received from the SDT extraction unit 43 and the SDT section data received from the SDT generation unit 44. The SDT synthesis unit 45 generates a plurality of TS packets including the multiplexed SDT section data. More specifically, the SDT synthesis unit 45 generates TS packets in which the SDT section data is divided and stored in the payload portion. The SDT synthesis unit 45 outputs the generated TS packets to the multiplexing unit 49.

[0074] The EIT extraction unit 46 receives the SI signal Sa1 from the IP reception unit 10 and extracts TS packets containing an EIT from the received SI signal Sa1. More specifically, the EIT extraction unit 46 references the headers of the TS packets included in the SI signal Sa1 received from the IP reception unit 10 and extracts TS packets with a PID of "0x0012" from among the TS packets included in the SI signal Sa1. The EIT extraction unit 46 generates section data of the EIT by combining data stored in the payloads of the extracted TS packets. The EIT extraction unit 46 outputs the generated section data to the EIT synthesis unit 48.

[0075] The EIT generation unit 47 receives EPG information for channel ch5 from a control device (not shown), and based on the received EPG information, generates section data of an EIT for channel ch5. The EIT generation unit 47 outputs the generated section data to the EIT synthesis unit 48.

[0076] The EIT synthesis unit 48 multiplexes the EIT section data received from the EIT extraction unit 46 and the EIT section data received from the EIT generation unit 47. The EIT synthesis unit 48 generates a plurality of TS packets including the multiplexed EIT section data. More specifically, the EIT synthesis unit 48 generates TS packets in which the EIT section data is divided and stored in the payload portion. The EIT synthesis unit 48 outputs the generated TS packets to the multiplexing unit 49.

[0077] The multiplexing unit 49 generates an SI signal Sa3, which is a stream obtained by multiplexing the TS packets generated by the NIT generation unit 42, the TS packets generated by the SDT synthesis unit 45, and the TS packets generated by the EIT synthesis unit 48 onto the SI signal Sa1 that has been subjected to the removal process by the packet filter 41. More specifically, the multiplexing unit 49 generates the SI signal Sa3 by multiplexing, in the time axis direction, the SI signal Sa1 received from the packet filter 41, the TS packets received from the NIT generation unit 42, the TS packets received from the SDT synthesis unit 45, and the TS packets received from the EIT synthesis unit 48. The multiplexing unit 49 outputs the generated SI signal Sa3 to the IP transmission unit 30.

[0078] The IP transmitting unit 30 transmits the IP packet Pa3 including the SI signal Sa3 after the rewriting process by the processing unit 40. More specifically, the IP transmitting unit 30 receives the SI signal Sa3 from the multiplexing unit 49, and transmits the plurality of IP packets Pa3 including the received SI signal Sa3 to the STB 301B via the hub 121 and the IP network 311B.

[0079] The STB 301B receives a plurality of IP packets Pa3 from the SI retransmission device 102 via the hub 121 and the IP network 311B, and can select channels ch1, ch2, and ch5 based on the NIT included in the received IP packets Pa3.

[0080] In the broadcasting system 402 according to the second embodiment of the present disclosure, the participating station 152 is configured to retransmit the content of channels ch1 and ch2 and distribute the content of the independent broadcast channel ch5, but this is not limited to this. The participating station 152 may also be configured to retransmit the content of all channels ch1, ch2, and ch3 distributed by the joint headend station 251 and distribute the content of the independent broadcast channel ch5. In this case, the processing unit 40 in the SI retransmission device 102 adds the information of channel ch5 to the channel selection information of the NIT included in the SI signal Sa1 without deleting the information of channel ch3 in the channel selection information.

[0081] The above-described embodiments should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0082] Each process (each function) in the above-described embodiments is realized by a processing circuit including one or more processors. The processing circuit may be configured as an integrated circuit or the like that combines one or more memories, various analog circuits, and various digital circuits in addition to the one or more processors. The one or more memories store programs (instructions) that cause the one or more processors to execute each of the processes. The one or more processors may execute each of the processes according to the program read from the one or more memories, or according to a logic circuit pre-designed to execute each of the processes. The processor may be various processors suitable for computer control, such as a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), a field programmable gate array (FPGA), and an application-specific integrated circuit (ASIC). Note that the physically separate processors may cooperate with each other to execute each of the processes. For example, the processors mounted on a plurality of physically separated computers may cooperate with each other to execute the above processes via a network such as a LAN (Local Area Network), a WAN (Wide Area Network), the Internet, etc. The program may be installed into the memory from an external server device or the like via the network, or may be distributed in a state stored on a recording medium such as a CD-ROM (Compact Disc Read Only Memory), a DVD-ROM (Digital Versatile Disc Read Only Memory), or a semiconductor memory, and installed into the memory from the recording medium.

[0083] The above description includes the following additional features. [Appendix 1] a receiving unit that receives an IP packet including a first SI signal that is an SI signal of a plurality of channels; an acquisition unit that acquires the first SI signal from the IP packet received by the receiving unit; a processing unit that generates a second SI signal by rewriting an NIT included in the first SI signal acquired by the acquisition unit; a transmitter for transmitting an IP packet including the second SI signal generated by the processor; The processing unit a packet filter that performs a removal process to remove NIT from the first SI signal; A generation unit that generates an NIT including channel selection information for the part of channels; a multiplexing unit that multiplexes the first SI signal after the removal process by the packet filter and the NIT generated by the generation unit.

[0084] [Appendix 2] a receiving unit that receives an IP packet including a first SI signal that is an SI signal of a plurality of channels; an acquisition unit that acquires the first SI signal from the IP packet received by the receiving unit; a processing unit that generates a second SI signal by rewriting an NIT included in the first SI signal acquired by the acquisition unit; a transmitter for transmitting an IP packet including the second SI signal generated by the processor; The NIT includes tuning information for the plurality of channels, the processing unit adds information of a first channel different from the plurality of channels to the channel selection information in the rewriting process; The processing unit an extraction unit that extracts TS packets in which table information different from the NIT is stored from the first SI signal and combines data stored in the extracted TS packets to generate first section data that is section data; a generating unit that generates second section data that is section data of the table information related to the first channel; an SI retransmission device including a synthesis unit that multiplexes the first section data generated by the extraction unit and the second section data generated by the generation unit, and generates a plurality of TS packets including the multiplexed section data.

[0085] [Appendix 3] An SI retransmission device, comprising: processing circuitry; The processing circuitry receiving an IP packet including a first SI signal that is an SI signal of a plurality of channels; Acquire the first SI signal from the received IP packet; generating a second SI signal by rewriting the NIT included in the acquired first SI signal; an SI retransmission device that transmits an IP packet including the generated second SI signal; [Explanation of symbols]

[0086] 10 IP receiver 20 Processing section 21 Packet Filter 22 NIT generation section 23 Multiplex section 30 IP transmission unit 40 Processing section 41 Packet Filter 42 NIT generation section 43 SDT Extraction Unit 44 SDT generation section 45 SDT synthesis section 46 EIT extraction part 47 EIT generation section 48 EIT synthesis section 49 Multiplex section 101,102 SI retransmission device 111 Switch 112 IP broadcasting equipment 121 Hub 151 participating stations 201 SI sending device 211,211A,211B,211C IP broadcast equipment 221 Hub 251 Joint Headend Station 301A, 301B STB 311A,311B IP network 401,402 Broadcasting System RA,RB distribution area

Claims

1. 1. An SI retransmission method in an SI retransmission device provided in a participating station capable of retransmitting content of some channels among content of a plurality of channels distributed by a common headend station, comprising: receiving an IP packet including a first SI signal, which is a Service Information (SI) signal of the plurality of channels; obtaining the first SI signal from the received IP packet; performing a rewriting process of rewriting an NIT (Network Information Table) included in the acquired first SI signal; and transmitting an IP packet including a second SI signal, which is the SI signal after the rewriting process.

2. a receiving unit that receives an IP packet including a first SI signal that is an SI signal of a plurality of channels; an acquisition unit that acquires the first SI signal from the IP packet received by the receiving unit; a processing unit that generates a second SI signal by rewriting an NIT included in the first SI signal acquired by the acquisition unit; a transmitting unit that transmits an IP packet including the second SI signal generated by the processing unit.

3. The NIT includes tuning information for the plurality of channels, The SI retransmission device according to claim 2 , wherein the processing unit generates the second SI by rewriting the channel selection information in an NIT included in the first SI.

4. The SI retransmission device according to claim 3, wherein the processing unit generates the second SI signal, which is an SI signal of a portion of the channels among the plurality of channels, by deleting information of a portion of the channels in the channel selection information.

5. 5. The SI retransmission device according to claim 3, wherein the processing unit generates the second SI signal by adding information about a channel different from the plurality of channels to the channel selection information.

Images