Transmitter and receiver

Abstract

To provide a transmitter and a receiver that make it possible to suppress an increase in a jitter amount on the transmission side and prevent video destruction on the reception side, enabling content in IP packet form to be transmitted in bulk.SOLUTION: A transmitter 11 according to the present invention comprises: a content distribution unit 111 which, when transmitting content in IP packet form in bulk via a plurality of broadcast transmission channels, identifies and separates the multiple types of content data on the basis of each destination IP address; a TLV signal generation unit 112 that converts it into a TLV packet string for each type and constructs a TLV stream; a flag addition unit 113 that adds, to the packet type field of a prescribed TLV packet in the TLV stream, a flag that is identifiable on the reception side and that indicates switching of the transmission channels; and a divided frame generation unit 114 that controls transmission of the TLV stream in bulk, on the basis of a prescribed divided frame. A transmitter 17 according to the present invention detects the flag and reconstructs the TLV stream.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to the technical fields of satellite broadcasting and terrestrial broadcasting, as well as fixed communications and mobile communications, and more particularly to transmitting and receiving devices for time-division multiplexing of digital data. [Background technology]

[0002] In digital transmission systems, multi-level modulation schemes are often used to transmit more information within the available frequency bandwidth for each service. To improve frequency utilization efficiency, increasing the number of bits assigned per symbol of the modulated signal (modulation order) is effective. However, the relationship between the upper limit of the information transmission rate per Hz and the signal-to-noise ratio is limited by the Shannon limit. Satellite digital broadcasting is an example of information transmission using satellite transmission channels.

[0003] In currently used satellite digital broadcasting, information correction is performed in receiving equipment using error correction codes. By adding a redundant signal called a parity bit to the information to be transmitted, it is possible to control the redundancy (coding rate) of the signal and improve resistance to noise. Error correction codes and modulation schemes are closely related, and the theoretical upper limit of frequency utilization efficiency with respect to the signal-to-noise ratio is called the Shannon limit. One of the powerful error correction codes that approaches the Shannon limit is the LDPC (Low Density Parity Check) code, which was proposed by Gallagher in 1962 (see, for example, Non-Patent Document 1).

[0004] LDPC codes are linear codes defined by a very sparse check matrix H (the elements of the check matrix consist of 0s and 1s, and the number of 1s is very small). LDPC codes are powerful error correction codes that, by increasing the code length and using an appropriate check matrix, can achieve transmission characteristics approaching the Shannon limit. LDPC codes are also used in ARIB STD-B44 (hereinafter referred to as the Advanced Satellite Broadcasting System (ISDB-S3)), which specifies the transmission method for current and next-generation broadcasting services such as 4K / 8K Super Hi-Vision satellite broadcasting (see, for example, Non-Patent Document 2). By combining multi-level modulation with powerful error correction codes such as LDPC codes, transmission with higher frequency utilization efficiency is becoming possible.

[0005] Incidentally, in recent years, there has been much expectation for the establishment of transmission technologies for next-generation content that surpasses 4K and 8K services, such as AR (Augmented Reality) and VR (Virtual Reality) 3D content. However, focusing on the 12GHz band used for satellite broadcasting, the available frequencies are congested, making it difficult to secure sufficient bandwidth for transmitting next-generation content that surpasses 4K and 8K services. In such situations where sufficient bandwidth cannot be secured, a technology called bulk transmission, which divides and transmits large-capacity data by bandwidth, is known (see, for example, Patent Document 1).

[0006] Furthermore, a transmission system is disclosed that is highly compatible with IP-based communication transmission lines and uses multiple broadcast transmission lines to divide predetermined data into TLV packet format and transmit it in bulk (see, for example, Patent Document 2). [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2009-260408 [Patent Document 2] Japanese Patent Publication No. 2020-123763 [Non-patent literature]

[0008] [Non-Patent Document 1] R. G Gallager, “Low Density Parity Check Codes,” in Research Monograph series Cambridge, MIT Press, 1963 [Non-Patent Document 2] "Advanced Broadband Satellite Digital Broadcasting Transmission System (ISDB-S3) Standard ARIB STD-B44 Version 2.1", [online], revised March 25, 2016, ARIB, [accessed June 6, 2022], Internet <URL: https: / / www.arib.or.jp / kikaku / kikaku_hoso / std-b44.html> [Overview of the project] [Problems that the invention aims to solve]

[0009] As mentioned above, while bulk transmission, a technology that divides and transmits large-capacity data by bandwidth, is known, a problem with bulk transmission as shown in Patent Documents 1 and 2 is that it lacks the function to specify a transmission path for each type of content data that constitutes a single piece of content. Furthermore, when specifying a transmission path for each type of content data that constitutes a single piece of content, when the signals from each transmission path that were divided and transmitted are combined and output at the receiving end, an increase in jitter is expected due to the output being in a different order / interval than the signal output order / interval before bulk transmission. This could potentially cause video corruption in the transmitted content due to memory overflow or other issues in the decoder or other devices downstream of the receiving device.

[0010] Accordingly, in view of the above-mentioned problems, an object of the present invention is to provide a transmitting device and a receiving device that suppress the increase in the amount of jitter on the transmitting side and prevent image degradation on the receiving side, thereby enabling bulk transmission of IP packet format content. [Means for solving the problem]

[0011] The transmission device of the present invention is a transmission device that bulk-transmits content in IP packet format in TLV (Type Length Value) packet format using a plurality of broadcast transmission paths, and inputs a plurality of content data to which destination IP addresses are assigned for each of the contents constituting the content in IP packet format input from a predetermined content streamer, identifies each destination IP address, determines the type of the plurality of content data, and performs sorting; content distribution means; a TLV signal generation means that converts the sorted signal in IP packet format according to the type of content data into a signal in TLV packet format for each type of content data and constitutes one TLV stream; for the TLV stream, a flag addition means that discriminates a continuous TLV packet sequence for each type of content data for bulk transmission according to the type of content data, and adds a flag for specifying a transmission path switchable on the receiving side to the packet type field of the TLV header in a predetermined TLV packet in the TLV stream; based on identification information predetermined so as to be able to identify at least the type and number of the transmission paths used for the bulk transmission, a divided frame with a frame length conforming to a common transmission method for a plurality of broadcast transmission paths used for the bulk transmission is determined, and when the information bit rate required for transmission of the TLV stream is within the maximum transmission rate of the plurality of broadcast transmission paths, the divided frame is constituted by a number of basic divided slots corresponding to the plurality of broadcast transmission paths, The aforementioned TLV stream when the information bit rate required for transmission of exceeds the maximum transmission rate that can be transmitted by the plurality of broadcast transmission paths, a predetermined number of additional basic divided slots for transmission via a communication transmission path of an IP network are added to constitute the divided frame, and a divided frame generation means that controls to bulk-transmit the TLV stream according to the type of content data based on the divided frame, and is characterized by comprising.

[0012] Also, in the transmission device of the present invention, the flag addition means is configured to add the flag at least to the packet type field of the TLV header in the TLV packet immediately before the transmission path is switched.

[0013] Also, in the transmission device of the present invention, the flag addition means is configured to add the flag while incrementing or decrementing from a predetermined value within the range of the undefined region to the packet type field of the target TLV packet for the number of transmission paths used for the bulk transmission.

[0014] Furthermore, the receiving device of the present invention is a receiving device that receives the content in the form of the IP packet transmitted in bulk by the transmission device of the present invention. Based on the predetermined identification information, it identifies the structure of the divided frame to determine a predetermined number of basic division slots, and for the signal in the form of the TLV packet received via the broadcast transmission path that constitutes the TLV stream transmitted in bulk according to the type of content data, and further for the IP-based packet transmitted via the communication transmission path of the IP network, when there is such a packet, it performs IP decapsulation and arranges the signal order based on the IP sequence number that uniquely specifies the signal order given in the packet, and then extracts the signal in the form of the TLV packet. For the signal in the form of the TLV packet, it sequentially assigns the TLV packet sequence in the order received to the basic division slots corresponding to each transmission path to reconstruct the divided frame generated by the transmission device. It includes a divided frame reconstruction means, a flag detection means for detecting the flag from the TLV packet sequence in each basic division slot of the reconstructed divided frame, and an output signal generation means for concatenating the TLV packet sequences in each basic division slot based on the position and value of the flag on the detected divided frame to restore the TLV stream. From the restored TLV stream, it extracts the data in the form of the IP packet that constitutes a plurality of content data to which the destination IP addresses are respectively assigned, and reconstructs each content data that constitutes the content in the form of the IP packet and outputs it to the destination device corresponding to each destination IP address. [Effects of the Invention]

[0017] According to the present invention, in a bulk transmission system that enables high-capacity transmission even in environments where the frequency of broadcast transmission lines is constrained, by specifying a transmission line for each type of content data that constitutes a single piece of content and performing bulk transmission, it is possible to reduce the signal jitter of the transmitting device output that may occur in the process, and to prevent image corruption due to memory overflow of decoders and other devices downstream of the receiving device. [Brief explanation of the drawing]

[0018] [Figure 1] This is a block diagram showing a schematic configuration of a transmission system comprising a transmitting device and a receiving device according to one embodiment of the present invention. [Figure 2] This is a schematic block diagram showing the configuration of a transmission system comprising a transmitting device and a receiving device according to one embodiment of the present invention. [Figure 3] This is a block diagram showing the schematic configuration of a transmitting device according to one embodiment of the present invention. [Figure 4] This figure shows an example of generating a signal in TLV packet format using a TLV signal generation unit in a transmitting device according to one embodiment of the present invention. [Figure 5] (a) shows an example of a TLV signal in which TLV packets for each content data generated by the TLV signal generation unit in one embodiment of the present invention are connected in a single line, and (b) shows an example in which a flag specifying the transmission path switching of TLV packets is added by the flag addition unit in one embodiment of the present invention. [Figure 6] This figure shows an example of transmission path switching when bulk transmitting a TLV signal in which TLV packets for each content data are connected in a single line, according to one embodiment of the present invention. [Figure 7] This is a diagram showing the configuration of a segmented frame used in a transmitting device according to one embodiment of the present invention. [Figure 8] This is a block diagram showing a schematic configuration of a receiving device according to one embodiment of the present invention. [Figure 9] This figure shows an example of restoring a TLV stream using a flag detection unit and an output signal generation unit in a receiving device according to one embodiment of the present invention. [Figure 10] (a) shows an example of a TLV signal in which TLV packets for each content data generated by the TLV signal generation unit in a transmission device according to one embodiment of the present invention are connected in a single line, and (b) shows an example in which a flag specifying the transmission path switching of TLV packets is added by the flag addition unit in a modified transmission device according to the present invention. [Modes for carrying out the invention]

[0019] Hereinafter, with reference to the drawings, a transmission system 1 comprising a transmitting device 11 and a receiving device 17 according to one embodiment of the present invention will be described in detail.

[0020] (Transmission system) Figure 1 is a block diagram illustrating the schematic configuration of a transmission system 1 comprising a transmitting device 11 and a receiving device 17 according to one embodiment of the present invention. In the example of the transmission system 1 shown in Figure 1, the system is configured to include a signal source device 10, a transmitting device 11, m (m>1) transmitters 12-1, 12-2, ..., 12-m (hereinafter collectively referred to as "transmitters 12"), m transmitting antennas 13-1, 13-2, ..., 13-m (hereinafter collectively referred to as "transmitting antennas 13"), a broadcasting satellite 14, in this example one receiving antenna 15, m receivers 16-1, 16-2, ..., 16-m (hereinafter collectively referred to as "receivers 16"), a receiving device 17, a display device 18, and an IP network 19.

[0021] In the transmission system 1 according to this embodiment, each of the m transmitters 12 and the corresponding m receivers 16 are devices compliant with the Advanced Satellite Broadcasting System (ISDB-S3) and are capable of data transmission using the coding and modulation schemes supported by ISDB-S3 (LDPC coding and the maximum multi-level modulation 32APSK under the current standard). Specifically, the transmitters 12-m perform LDPC coding processing on the data to be transmitted according to a predetermined LDPC coding rate (BCH coding may also be added), generate a modulated signal with mapping according to a predetermined modulation scheme, and uplink to the broadcast satellite 14. The broadcast satellite 14 downlinks the modulated signal to the receiving antenna 15. The receivers 16-m receive the modulated signal via the receiving antenna 15, perform demodulation and decoding processing corresponding to the coding and modulation scheme of the transmitters 12-m, and restore the data transmitted from the transmitters 12-m. Alternatively, a single receiver with the functions of m receivers 16 may be used.

[0022] In other words, the m transmitters 12, m transmitting antennas 13, broadcast satellites 14, receiving antennas 15, and m receivers 16 constitute multiple (m) broadcast transmission paths, similar to a so-called Multi-Input Multi-Output (MIMO) or Multi-Input Single-Output (MISO) broadcast transmission system. The IP network 19 constitutes a communication transmission path in an IP-based communication transmission system. For example, the IP network 19 can be a general communication transmission path composed of Internet protocols such as IPv4 or IPv6. In this example, an example using multiple satellite transmission paths as broadcast transmission paths is described, but it is not limited to this, and a system using multiple next-generation terrestrial transmission paths may also be used.

[0023] The transmitting device 11 then controls m transmitters 12 to bulk transmit the content of the large-capacity data acquired from the signal source device 10 to the receiving device 17, using multiple broadcast transmission lines (in this example, satellite transmission lines) and, if necessary, communication transmission lines via the IP network 19.

[0024] The signal source device 10 shown in Figure 1 is a device that sends data to be transmitted by this transmission system 1 to the transmitting device 11. Since the transmitting device 11 can also utilize the communication transmission path via the IP network 19, it is possible to send data to the transmitting device 11 even at a transmission rate higher than the maximum transmission rate that can be transmitted by the m-unit transmitters 12.

[0025] For example, the transmitting device 11 transmits from the signal source device 10 to a transmitter 12 that exceeds the maximum transmission rate that can be transmitted by the m-type transmitter 12. all The system inputs data at an information bitrate and distributes it to m transmitters 12 and the IP network 19 based on a segmented frame described later as one embodiment, referring to Figure 7. Specifically, the transmitter 11 outputs the data at information bitrate I1 to transmitter 12-1, information bitrate I2 to transmitter 12-2, and information bitrate I to transmitter 12-m. m The data is distributed, and for the remaining data exceeding the maximum transmission rate that can be transmitted by the m-unit transmitters 12, the information bitrate I is applied to the IP network 19. n Then, the content of the large-capacity data acquired from the signal source device 10 is distributed and output.

[0026] The information bitrate of the large-capacity data acquired from the signal source device 10 is I all In that case, all and the information bitrates I1, I2, ..., I after distribution by the transmitting device 11 n Between these two points, if the measurement range of the information bitrate is limited to the actual data such as video and audio to be transmitted (payload excluding the header), then the following equation (1) holds true.

[0027]

number

[0028] Here, when transmitting the large-capacity data acquired from the signal source device 10, the transmission device 11 has pre-determined m transmitters 12 to be used as satellite transmission paths. Since the maximum value that can be transmitted is determined by the modulation method and LDPC coding rate set for each of the m transmitters 12, from each of the m transmitters 12, the TMCC (Transmission and Multiplexing Configuration Control) information (TMCC1, TMCC2, …, TMCC m ) is acquired, and the information bit rates I1, I2, …, I m can be determined. Incidentally, when it is pre-determined that the m transmitters 12 use a fixed coding and modulation method, the information bit rates I1, I2, …, I m can be determined without depending on the TMCC information.

[0029] And when there is a part of the data (data with the information bit rate I n ) after distribution to be sent via the IP network 19, for that data as well, a split frame exemplified in FIG. 7 described later is configured. However, when the information bit rate I all of the content of the large-capacity data acquired from the signal source device 10 can be transmitted only by the m transmitters 12 without using the IP network 19, it may be configured to distribute the large-capacity data within the range of the m transmitters 12.

[0030] For each of the m transmitters 12, modulation signals based on their respective coding and modulation methods are generated for each of the data with the information bit rates I1, I2, …, I m distributed to them, and are uplinked to the broadcast satellite 14 via their respective transmitting antennas 13.

[0031] Each of the modulation signals from the m transmitters 12 uplinked to the broadcast satellite 14 is downlinked all at once towards the receiving antenna 15 in the service area covered by the broadcast satellite 14.

[0032] Each of the m receivers 16 receives the corresponding modulated signal from the m transmitters 12 via the receiving antenna 15, performs demodulation and decoding processing corresponding to the coding and modulation scheme of each of the m transmitters 12, and recovers the data transmitted from the m transmitters 12, and obtains TMCC information (TMCC1, TMCC2, ..., TMCC m ) is sent to the receiving device 17 along with it.

[0033] In this example, the receiving device 17 receives TMCC information (TMCC1, TMCC2, ..., TMCC) from m receivers 16. m Based on this, the information bitrates I1, I2, ..., I transmitted from the m-unit transmitter 12 m For each data point, the divided frame described later is reconstructed with reference to Figure 7. Furthermore, the receiving device 17 receives a portion of the distributed data (information bitrate I) transmitted from the transmitting device 11 via the IP network 19. n If data (such as the one shown below) is available, that data is also received, and the segmented frames exemplified in Figure 7, described later, are reconstructed.

[0034] Then, the receiving device 17 receives segmented data (information bitrate I1, I2, ..., I) transmitted via the m receivers 16 and the IP network 19. n All of the data is received, and the valid data of each basic division slot in the reconstructed division frame is concatenated to form large-capacity data (information bitrate I) in the same signal format as that sent from the signal source device 10. all The system restores the content of the data (equivalent to the data transmitted), generates an output signal suitable for the display device 18, and outputs it to the display device 18.

[0035] The display device 18 reproduces the large-capacity data transmitted from the signal source device 10 via the receiving device 17. Alternatively, a recording device that records the large-capacity data onto a recording medium may be used instead of the display device 18.

[0036] Furthermore, the connection between the transmitting device 11 and the signal source device 10, and between the transmitting device 11 and m transmitters 12, may be a direct communication method using a dedicated line, or a connection via an IP-based local area network. Similarly, the connection between the receiving device 17 and the display device 18, and between the receiving device 17 and m receivers 16, may be a direct communication method using a dedicated line, or a connection via an IP-based local area network.

[0037] By the way, when the transmission system 1 of one embodiment shown in Figure 1 is configured to transmit multiple types of content data constituting one content in bulk, a technique is required to reduce signal jitter at the output of the transmitting device 11 and to reliably prevent image corruption due to memory overflow of the decoder, etc., in the display device 18 downstream of the receiving device 17.Therefore, when the transmission system 1 of one embodiment shown in Figure 1 is configured to transmit multiple types of content data constituting one content in bulk, the transmission system 1a of that embodiment is configured as shown in Figure 2.Figure 2 is a schematic block diagram showing the configuration of the transmission system 1a comprising a transmitting device 11 and a receiving device 17 of one embodiment according to the present invention.

[0038] The transmission system 1a of one embodiment shown in Figure 2 differs from the one shown in Figure 1 in that it is configured with a content streamer 10a as one embodiment of the signal source device 10 shown in Figure 1, and the display device 18 has a 4K decoder 18-1 configured as a decoder for 4K video signals and an AR decoder 18-2 configured as a decoder for AR video signals as one embodiment.

[0039] The content streamer 10a sends a signal of content in IP packet format (3D content in this example) to the transmission device 11 of this embodiment. In this example, the 3D content signal consists of two types of content data signals in IP packet format: a 4K video signal and an AR video signal. It will be explained that destination IP addresses in IP packet format are pre-assigned, denoted as X for the 4K decoder 18-1 for the 4K video signal and Y for the AR decoder 18-2 for the AR video signal.

[0040] Therefore, the transmitter 11 in one embodiment shown in Figure 2 bulk transmits the IP packet-format content signal (3D content in this example) input from the content streamer 10a to the receiver 17 according to the type of content data (two types in this example: 4K video signal and AR video signal) according to the destination IP addresses X and Y. In particular, the transmitter 11 in this embodiment bulk transmits the 4K video signal using the first to m satellite transmission paths and the AR video signal using the IP line (communication transmission path via the IP network 19 described above). To do this, it first converts the content data into a series of TLV packets sorted according to the type of content data and generates a TLV stream that constitutes a TLV signal. Furthermore, the transmitting device 11 of this embodiment specifies a transmission path according to the type of content data, and provides a flag that specifies the switching of this transmission path (i.e., a flag managed between the transmitting device 11 and the receiving device 17 as information for the receiving device 17 to identify the transmission path after switching, and consequently a flag for identifying the output order of TLV packets from the transmitting device 11). This flag is added to the TLV header of a predetermined TLV packet in the TLV stream, and then bulk transmission of the 3D content is performed to the receiving device 17 of this embodiment via each transmission path.

[0041] In this embodiment, the receiving device 17 receives a sequence of TLV packets transmitted from the transmitting device 11 via multiple transmission paths, and restores the TLV stream constituting the TLV signal by referring to the flags mentioned above. Furthermore, the receiving device 17 in this embodiment distributes signals according to the type of content data (in this example, two types: 4K video signals and AR video signals) according to the destination IP address in the IP packet format described above, and outputs them to the destination devices (4K decoder 18-1 and AR decoder 18-2) on the display device 18 corresponding to each destination IP address. Each of the 4K decoder 18-1 and AR decoder 18-2 performs the decoding process necessary to display the 3D content by combining the 4K video signal and the AR video signal on the display device 18 (not shown).

[0042] The following describes in more detail the transmitting device 11 and the receiving device 17 according to one embodiment of the present invention.

[0043] (Transmitter) Figure 3 is a block diagram showing the schematic configuration of a transmission device 11 according to one embodiment of the present invention. The transmission device 11 of this embodiment includes a content distribution unit 111, a TLV signal generation unit 112, a flag addition unit 113, a segmented frame generation unit 114, and an IP encapsulation unit 115.

[0044] The content distribution unit 111 receives information bitrate I from the content streamer 10a. all The content distribution unit 111 receives multiple content data, each of which is assigned a destination IP address, as input as large-capacity data (including video and audio, etc.) in IP packet format. It identifies each destination IP address, determines the type of the multiple content data, and distributes them before outputting them to the TLV signal generation unit 112. In this embodiment, the content distribution unit 111 receives two types of content data, each of which is assigned a destination IP address X and Y, as input from the content streamer 10a as a 3D content in IP packet format. It identifies each destination IP address, determines the type of the two types of content data, and distributes them accordingly.

[0045] The TLV signal generation unit 112 receives signals in IP packet format (hereinafter also referred to as "IP signals") from the content distribution unit 111, which are distributed according to the type of content data (in this example, two types: 4K video signals and AR video signals), converts (stores) them into TLV packet format signals for each type of content data (for example, see ARIB STD-B32, Volume 3, p.20, 3.5, TLV packets), and outputs them to the flag addition unit 113.

[0046] More specifically, the TLV signal generation unit 112 determines the packet length of each IP packet for each type of content data (in this example, two types: 4K video signals and AR video signals), generates a 4-byte TLV header conforming to the TLV packet format signal, and adds it to the TLV packet payload. Figure 4 shows an example of generating a TLV packet format signal by the TLV signal generation unit 112 in a transmission device 11 of one embodiment of the present invention. Typically, a TLV header consists of a packet type field (1 byte indicating "0x7F" and 1 byte indicating the type) and a packet length field (length). In the current TLV packet format, the packet type field constitutes an undefined area of ​​"0x04~0xFD", and this packet type field is used as an additional area for the "flag specifying transmission path switching" according to the present invention, which will be described later.

[0047] Also, information bitrate I from content streamer 10a allThe 3D content, input as large-capacity data (including video and audio, etc.), is in IP packet format and consists of signals in IP packet format, with each IP packet comprising an IP header and an IP packet payload. The IP packet payload may also contain other header information (e.g., a UDP (User Datagram Protocol) header) (not shown in the diagram), and may further contain MMT signals that constitute an MMTP packet, consisting of an MMTP header and an MMTP packet payload.

[0048] In this embodiment, the 3D content transmitted from the content streamer 10a is configured as a collection of IP packet signals constituting an MMTP packet, consisting of a first IP data flow to destination IP address X that originally represents 4K video signal content data, and a second IP data flow to destination IP address Y that represents AR video signal content data. Furthermore, each IP header in the IP packet sequence constituting the first IP data flow to destination IP address X is assigned a first signal source sequence number indicating its signal order, and each IP header in the IP packet sequence constituting the second IP data flow to destination IP address Y is assigned a second signal source sequence number indicating its signal order.Therefore, in the example shown in Figure 4, the TLV signal generation unit 112 extracts the IP packet payload from one or more IP packets in the order of the first signal source sequence numbers for the first IP data flow, stores them in the TLV packet payload, and constitutes one TLV packet. Similarly, for the second IP data flow, the TLV signal generation unit 112 extracts the IP packet payload from one or more IP packets in the order of the second signal source sequence number, stores them in the TLV packet payload, and constitutes one TLV packet.

[0049] However, as a modification of the example shown in Figure 4, the TLV signal generation unit 112 may, for the first IP data flow, store the data (including the IP header and IP packet payload) directly into the TLV packet payload for one or more IP packets in the order of the first signal source sequence number, thereby constituting a single TLV packet. Similarly, the TLV signal generation unit 112 may, for the second IP data flow, store the data (including the IP header and IP packet payload) directly into the TLV packet payload for one or more IP packets in the order of the second signal source sequence number, thereby constituting a single TLV packet. Furthermore, as an application example, if an MMT signal is configured within the IP packet payload, the MMT signal may also contain package information that associates the first IP data flow with the second IP data flow.

[0050] In this way, the TLV signal generation unit 112 constructs a TLV signal that forms a single TLV stream from the TLV packet format signals (i.e., the TLV packet sequence signals) that have been sequentially generated for each type of content data, and outputs it to the flag addition unit 113.

[0051] The flag-adding unit 113 receives the TLV stream from the TLV signal generation unit 112, identifies a sequence of TLV packets (referred to as a "TLV packet flow" in this specification) for each type of content data in order to perform bulk transmission according to the type of content data, adds a flag that specifies transmission path switching identifiable by the receiving device 17 to the packet type field of the TLV header in a predetermined TLV packet (hereinafter abbreviated as "TLVP" as appropriate) in the TLV stream, and outputs it to the segmented frame generation unit 114.

[0052] Here, referring to Figures 5 and 6, we will describe, as a concrete example, a TLV signal (a single TLV stream) in which TLV packets (TLVPs) for each content data (4K video signal and AR video signal) are connected in a single line, and an example in which a flag specifying transmission path switching is added. Figure 5(a) shows an example of a TLV signal (a single TLV stream) in which TLV packets (TLVPs) for each content data (two types: 4K video signal and AR video signal) are connected in a single line, generated by the TLV signal generation unit 112 in one embodiment of the present invention. Figure 5(b) shows an example in which a flag specifying transmission path switching is added by the flag addition unit 113 in one embodiment of the present invention to indicate the output transmission path of the TLV packet (TLVP) (either of two satellite transmission paths with m=2 or an IP line). Figure 6 shows an example of transmission path switching when bulk transmitting a TLV signal (one TLV stream) in which each TLV packet (TLVP) for content data (4K video signal and AR video signal) is connected in one line in a transmission device 11 according to one embodiment of the present invention.

[0053] First, as shown in Figure 5(a), the TLV signal generation unit 112 constructs a TLV signal that forms a single TLV stream from the TLV packets (TLVPs) sequentially generated for each type of content data. Here, the single TLV stream shown in Figure 5(a) is an example of a signal that can transmit TLV packets representing 4K video signal content data at approximately 25 Mbps (modulation method QPSK, LDPC coding rate 7 / 9) using two satellite transmission lines with an information bitrate of m=2, and TLV packets representing AR video signal content data at approximately 125 Mbps using an IP line. Furthermore, the TLV signal generation unit 112 constructs a TLV signal that forms a single TLV stream in a manner that allows for the identification of TLV packets and their signal order that represent content data of a 4K video signal (in the figure, TLV packets 4K_#1, 4K_#2, 4K_#3, ... that maintain the IP signal order of the first signal source sequence number) and TLV packets and their signal order that represent content data of an AR video signal (in the figure, TLV packets IP_#1, IP_#2, IP_#3, ... that maintain the IP signal order of the second signal source sequence number), and outputs it to the flag addition unit 113. As mentioned above, the content data that constitutes the 3D content in IP packet format is of two types in this example: a 4K video signal and an AR video signal. A destination IP address in IP packet format, simply shown as X for the 4K decoder 18-1 of the 4K video signal and simply shown as Y for the AR decoder 18-2 of the AR video signal, is pre-assigned.

[0054] Then, as shown in Figure 5(b), in this embodiment, the flag-adding unit 113 adds a flag to specify transmission path switching to the packet type field of the TLV header in the TLVP immediately before the transmission path switches (i.e., the TLVP immediately before the TLVP at the beginning of the TLV packet flow for each transmission path that will be used as the output destination). For example, in this embodiment shown in Figure 5(b), a TLV packet flow in which one or more TLVPs indicating content data of a 4K video signal are consecutive (one TLVP at a time in this example) is transmitted across two satellite transmission paths with m=2, and a flag to specify transmission path switching is added to the packet type field of the TLV header in the TLVP immediately before the transmission path switches (i.e., the TLVP immediately before the TLVP at the beginning of the TLV packet flow for each transmission path that will be used as the output destination).

[0055] Furthermore, as shown in Figure 5(b), in order to improve the accuracy of the TLV stream reconstruction based on the detection of the flag on the receiving device 17 side, it is preferable to add the flag specifying the transmission path switching to the packet type field of the target TLV packet by incrementing (or decrementing) from a predetermined value within the undefined range (in this example, "0x04 to 0xFD") for the number of transmission paths used for the bulk transmission (in this example, 3 paths: 2 satellite transmission paths and an IP line). For example, the flag indicating IP line output is added to the packet type field of the target TLV packet as Type=0x04, the flag indicating the first satellite transmission path output is added to the packet type field of the target TLV packet as Type=0x05, and the flag indicating the second satellite transmission path output is added to the packet type field of the target TLV packet as Type=0x06. In this embodiment, if a subsequent TLV packet does not involve a transmission path switch, a predetermined value (for example, Type=0xFD) that is not used as a flag to specify a transmission path switch is added to the packet type field of the immediately preceding TLV packet.

[0056] Therefore, as shown in Figure 5(b), the flag-adding unit 113 adds a flag to specify transmission path switching and outputs it to the segmented frame generation unit 114 as a single TLV stream in a manner that allows identification of the TLV packets and their signal order in each TLV packet flow.

[0057] The segmented frame generation unit 114 shown in Figure 3 first determines segmented frames with frame lengths compliant with a common transmission method (ISDB-3 in this embodiment) for multiple broadcast transmission lines used for bulk transmission, based on pre-defined identification information (in this example, TMCC information obtained from each of the m transmitters 12) that allows at least the type and number of transmission lines used for bulk transmission to be identified. Then, the segmented frame generation unit 114 constructs the segmented frame with a number of basic segmented slots corresponding to the multiple broadcast transmission lines if the information bitrate required for the transmission of the TLV stream is within the maximum transmission rate of the multiple broadcast transmission lines. If the information bitrate required for the transmission of the predetermined data exceeds the maximum transmission rate that can be transmitted through the multiple broadcast transmission lines, it further constructs the segmented frame by adding a predetermined number of basic segmented slots (one basic segmented slot in this example) for transmission via the communication transmission line (IP line) of the IP network 19. The segmented frame generation unit 114 then controls the connection of each transmitter 12 in the multiple broadcast transmission lines, as well as the IP network 19 to the communication transmission line, so that the TLV stream is transmitted in bulk according to the type of content data based on the segmented frame.

[0058] In particular, in this embodiment shown in Figure 5, the segmented frame generation unit 114 can identify and distribute a sequence of TLV packets (TLV packets 4K_#1, 4K_#2, 4K_#3, 4K_#4, 4K_#5, ...) representing the content data of a 4K video signal into a sequence of TLV packets to be transmitted using a first satellite transmission path (TLV packets 4K_#1, 4K_#3, 4K_#5, 4K_#7, 4K_#9, ...) and a sequence of TLV packets to be transmitted using a second satellite transmission path (4K_#2, 4K_#4, 4K_#6, 4K_#8, 4K_#10, ...). Furthermore, the segmented frame generation unit 114 can identify a sequence of TLV packets to be transmitted using an IP line as a sequence of TLV packets (TLV packets IP_#1, IP_#2, IP_#3, IP_#4, IP_#5, ...) representing the content data of an AR video signal.

[0059] Furthermore, in this example, the TMCC information obtained from each transmitter 12 in each satellite transmission path related to the first IP data flow includes, as identification information, the number of slot divisions for constructing the divided frame exemplified in Figure 7 described later, and a unique number indicating the basic divided slot corresponding to each transmitter 12, and is pre-scheduled. However, in this example, the identification information for identifying the transmission path used for bulk transmission is the TMCC information obtained from each of the m transmitters 12, but it may also be predetermined to be known between the transmitting device 11 and the receiving device 17, or it may be transmitted separately via a communication transmission path using an MMT signal.

[0060] Therefore, the segmented frame generation unit 114, based on the flags that specify transmission path switching added by the flag addition unit 113 and the TMCC information obtained from the m transmitters 12, configures segmented frames (see Figure 7) for adjusting the information bitrate related to distribution of the TLV stream input from the flag addition unit 113 to the satellite transmission path via the m transmitters 12 and the IP line via the IP network 19, and distributes the content data according to its type for bulk transmission based on these segmented frames.

[0061] Figure 7 is a diagram showing the configuration of a segmented frame used in a transmission device 11 according to one embodiment of the present invention. As shown in Figure 7, the segmented frame generated by the segmented frame generation unit 114 has m=2 in this example, with the width corresponding to the frame length and the height corresponding to the number of segmented slots, and this segmented frame is composed of a plurality of basic segmented slots. Each basic segmented slot has a frame length that corresponds to the transmission frame length of the broadcast transmission line transmission method (ISDB-S3 in this example) (equivalent to 120 slots of ISDB-S3), and is set to be easily synchronized with the broadcast transmission line transmission method (synchronized with 120 transmission frame slots of ISDB-S3), and capable of accommodating data of an encoding and modulation scheme supported by the broadcast transmission line transmission method (ISDB-S3 in this example) (for example, modulation scheme QPSK, LDPC coding rate 7 / 9).

[0062] For example, one TLV stream constituting the TLV signal input to the segmented frame generation unit 114 is arranged in ascending order from basic segmentation slot #1 to basic segmentation slot #n, with TLV packets as shown in Figure 6, for the corresponding transmission path. A null (or null TLV packet) is inserted at the end of each basic segmentation slot to adjust the frame length of the segmented frames to be uniform. Here, the TLV packet sequence in basic segmentation slot #1 is for transmission via the first satellite transmission path through transmitter 12-1, the TLV packet sequence in basic segmentation slot #2 is for transmission via the second satellite transmission path through transmitter 12-2, and the TLV packet sequence in basic segmentation slot #n is for transmission via the communication transmission path (IP line) through the IP network 19.

[0063] Furthermore, assuming that the delay difference between each transmission path (in this example, two satellite transmission paths and an IP line) is small enough that no signal order reordering error occurs on the receiving device 17 side, the segmented frame generation unit 114 stores the maximum number of TLV packets for each transmission path corresponding to each basic segmented slot, or a fixed number predetermined between the transmitting device 11 and the receiving device 17. On the other hand, when configuring a transmission system 1a with a large delay difference between each transmission path, the segmented frame generation unit 114 assigns a segmented frame number to the type field in the TLV header of the TLV packet located at the beginning of each basic segmented slot #1 to #m by incrementing (or decrementing) it with a numerical value that is indistinguishable from the flag that specifies the transmission path switching. By referring to such a segmented frame number, the delay difference can be corrected. In this case as well, in this embodiment, since a flag that specifies the transmission path switching is added in addition to the leading TLV header in each segmented frame, the signal order is corrected to match by flag detection on the receiving device 17 side.

[0064] Furthermore, when storing IP packets that constitute IP signals for each type of content data from the content streamer 10a shown in Figure 4 directly in the TLV packet payload (including the IP header and IP packet payload), the receiving device 17 can detect flags and correct the signal order to match. Specifically, in 3D content, each IP packet sequence in the first IP data flow to destination IP address X and the second IP data flow to destination IP address Y is assigned first and second signal source sequence numbers indicating their respective signal order. Moreover, if package information that associates the first IP data flow and the second IP data flow when MMT signals are configured is described, these can be used to detect flags on the receiving device 17 and correct the signal order to match.

[0065] Furthermore, even when configuring a transmission system 1a with large delay differences between each transmission path, in order to reliably reconstruct segmented frames with matching signal order on the receiving device 17 side, the segmented frame generation unit 114 may generate TMCC information by embedding information that identifies the TLV packets stored in each basic segmented slot (information indicating which TLV packets, identifiable by which first and second signal source sequence numbers, are stored in which basic segmented slot in which segmented frame) into the empty area of ​​the TMCC information obtained from the m transmitters 12, and then notify the m transmitters 12 of the update and transmit it.

[0066] As a variation of this, since a TLV stream is a sequence of TLV packets identified by a TLV stream ID, TLV packets containing TLV transmission control signals that indicate the physical configuration of each IP data flow that can be associated with each TLV packet flow may be appropriately generated and inserted on each transmission path. For example, although the diagrammatic explanation is omitted, a basic partitioning slot consisting only of a sequence of TLV packets containing TLV transmission control signals may be configured and transmitted periodically using any or all of the basic partitioning slots #1 to #m (m=2 in this example) shown in Figure 7, or a configuration may be used in which TLV packets containing the TLV transmission control signals are inserted as TLV packets located at the beginning of each of the basic partitioning slots #1 to #m illustrated in Figure 7.

[0067] In this way, the segmented frame generation unit 114 configures segmented frames (see Figure 7) to adjust the information bitrate for distribution to m transmitters 12 in a timely manner based on the TMCC information. Then, based on these segmented frames, the segmented frame generation unit 114 divides and distributes one TLV stream that constitutes the TLV signal input from the flagging unit 113 to the subsequent m transmitters 12 and the IP network 19, with the TLV signal input from the TLV signal generation unit 112.

[0068] The segmented frame generation unit 114 operates to distribute the large amount of data from the content streamer 10a in segmented frame units to m transmitters 12 and the IP network 19. This stabilizes the distribution operation when performed in clock synchronization, and since the payload size that can be accommodated in the transmission frame (ISDB-S3 transmission frame in this example) of each of the m transmitters 12 matches the payload size of the basic segmented slot, it becomes easy to connect to the m transmitters 12.

[0069] Furthermore, even if the coding and modulation schemes of each of the m transmitters 12 are individually different and variable, the segmented frame generation unit 114 can set the payload size of each corresponding basic segmented slot based on the TMCC information acquired from each of the m transmitters 12. This allows control to ensure that the information bitrate for each of the m transmitters 12 remains constant. In other words, the information bitrate of each basic segmented slot is determined based on the TMCC information of each of the m transmitters 12.

[0070] Furthermore, when the number of data distributions to the m transmitters 12 and IP network 19 is varied according to the TMCC information (i.e., when the total number of basic division slots constituting one division frame is varied), the segmented frame generation unit 114 notifies each of the m transmitters 12 of the information regarding the number of slot divisions (n ​​in this example) and the unique number (1 to m in this example) indicating the basic division slot corresponding to each transmitter 12, and the TMCC information (TMCC1, TMCC2, ..., TMCC) in each of the m transmitters 12 is notified. m It is preferable to configure the system to transmit signals from m transmitters 12 to the receiving device 17 using a specific method. This allows the receiving device 17, which will be described in detail later, to easily reconstruct a single segmented frame.

[0071] In other words, the information on the number of slot divisions that is notified to all m transmitters 12 being used corresponds to the total number of basic division slots (n) in the division frame shown in Figure 7. The unique number (1 to m in this example) indicating the basic division slot that is notified to each of the m transmitters 12 corresponds to the unique number that identifies each basic division slot shown in Figure 7.

[0072] Therefore, when the number of data distributions to m transmitters 12 and the IP network 19 is made variable according to the TMCC information (i.e., when the total number of basic division slots constituting one division frame is made variable), the division frame generation unit 114 notifies the transmitters by embedding identification information indicating the number of slot divisions (n ​​in this example) and a unique number (1 to m in this example) indicating the basic division slot corresponding to each transmitter 12 into the extended area of ​​the TMCC information obtained from each of the m transmitters 12 and sending it back. ISDB-S3 has 3614 bits available as the extended area of ​​the TMCC information, and has sufficient free space to independently transmit the information of the number of slot divisions and the unique number of the basic division slot. However, this identification information indicating the number of slot divisions and the unique number of the basic division slot may also be notified from the division frame generation unit 114 to each of the m transmitters 12 via the local area network, or it may be embedded in each basic division slot.

[0073] Furthermore, as shown in Figure 4, when it is specified that data be transmitted in MMT signal format within the TLV packet payload, identification information indicating the number of slot divisions and the unique number of the basic division slots may be embedded in the MMTP header. In the case of MMT, an extended area is reserved in the MMTP header, and it is possible to use this to notify the number of slot divisions and the unique number of the basic division slots. Thus, when it is specified to store a signal format that has unique header information, such as MMT, the notification is made using the free area of ​​the header information. Also, since it is unlikely that the number of slot divisions will be changed frequently, it is possible to pre-determine and make known the number of slot divisions and the unique number of the basic division slots, which are scheduled at the transmission time, between the sender and receiver (transmitter 11 and receiver 17) for unique information such as the frequency allocation of each transmitter 12, or to pre-notify the receiver 17 from the transmitter 11 before the transmission of the large amount of data.

[0074] The IP encapsulation unit 115 shown in Figure 3 has an information bitrate of I n Then, a sequence of TLV packets (a sequence of TLV packets in the basic division slot #n shown in Figure 7) containing content data (in this example, the second IP data flow of the AR video signal) to be transmitted over the IP line acquired from the content streamer 10a is given header information according to an Internet protocol such as IPv4 or IPv6, and IP encapsulation is performed to form an IP-based signal (such as an IP packet or Ethernet® frame), which is output to the IP network 19 and transmitted to the receiving device 17 via the IP network 19.

[0075] In particular, the IP encapsulation unit 115 has means for dividing the TLV packet sequence of the basic division slot #n into IP-based packets consistent with the IP network 19, and for assigning an IP sequence number to each divided IP-based packet to uniquely indicate the signal order of the packets, and transmitting them to the receiving device 17.

[0076] The receiving device 17 will sort the received IP-based signals sequentially based on the header information, and then extract the TLV packet sequence in the basic division slot #n shown in Figure 7. However, the transmitting device 11 will not transmit information bitrate I exceeding the maximum transmission rate that can be transmitted by content streamers 10a to m transmitters 12. all The transmission to the IP network 19 may be used only when transmitting data to the receiving device 17. Note that the basic division slot #n shown in Figure 7 may be multiple slots, but in this embodiment, since the configuration primarily uses a broadcast transmission path with high transmission time stability, it is set to one slot. Furthermore, when transmitting large amounts of data from the transmitting device 11 to the receiving device 17 using a broadcast transmission path (satellite transmission path in this example) and a communication transmission path (IP line), the size is the same as the basic division slot size for transmission by m transmitters 12, from the viewpoint of ease of reconfiguring the division slots on the receiving device 17 side (concatenation of TLV packets within each basic division slot).

[0077] As described above, in one embodiment of the transmission system 1a according to the present invention, the transmission device 11 distributes the content of large-capacity data in IP packet format (3D content in this example) input from the content streamer 10a to a specified number of transmission paths based on the content data corresponding to the destination IP address attached to the IP header of the IP packet constituting the IP signal. Furthermore, in the transmission device 11 of this embodiment, each distributed IP packet sequence is converted into a signal of a TLV packet sequence to form a TLV stream, and then a flag specifying transmission path switching that can be identified by the receiving device 17 is added to the packet type field in the TLV header of a predetermined TLV packet and transmitted in bulk, which is then used by the receiving device 17 to restore the bulk transmitted TLV stream.

[0078] (Receiving device) The following describes in detail an embodiment of the receiving device 17 according to the present invention, which corresponds to the transmitting device 11 shown in Figure 3.

[0079] Figure 8 is a block diagram showing the schematic configuration of a receiving device 17 according to one embodiment of the present invention. This receiving device 17 includes a segmented frame reconstruction unit 171, an IP decapsulation unit 172, a flag detection unit 173, an output signal generation unit 174, and a content redistribution unit 175.

[0080] First, the IP decapsulation unit 172 processes the signal (information bitrate I) transmitted from the transmitting device 11 via the IP network 19. n When a signal is present, IP decapsulation is performed, and the signal sequence is sorted based on an IP sequence number that uniquely identifies the signal sequence assigned within the packet. Then, the TLV packet sequence in the basic partitioning slot #n shown in Figure 7 is extracted and output to the partitioned frame reconstruction unit 171.

[0081] When the segmented frame reconstruction unit 171 receives the TLV stream transmitted in bulk according to the type of content data, it first uses the predetermined identification information (in this example, TMCC information obtained from m receivers 16 corresponding to m transmitters 12 (TMCC1, TMCC2, ..., TMCC m Based on this, the structure of the divided frame (such as the number of slot divisions in the basic divided slot) is identified and a predetermined number of basic divided slots are determined. Then, the divided frame reconstruction unit 171 sequentially assigns the TLV packet format signals received via the broadcast transmission path that constitutes the TLV stream transmitted in bulk according to the type of content data, and if there are IP-based packets transmitted via the communication transmission path of the IP network, IP decapsulation is performed and the signal order is sorted based on the IP sequence number that uniquely indicates the signal order assigned within the packet, and then extracts the TLV packet format signals, to the basic divided slots corresponding to each transmission path in the order in which they were received, and reconstructs the divided frame generated by the transmitting device 11.

[0082] For example, the segmented frame reconstruction unit 171 sequentially assigns TLV packet sequences to the basic segmented slots corresponding to each broadcast transmission path (in this example, the first and second satellite transmission paths) in the order they are received, and the information bitrates I1, I2, ..., I transmitted from the m transmitters 12 m For each data, a null (or null TLV packet) is inserted at the end of each basic division slot to reconstruct the division frame as illustrated in Figure 7. Furthermore, the division frame reconstruction unit 171 sequentially assigns the TLV packet sequence obtained via the IP network 19 to the basic division slot #n in the order it was received from the IP decapsulation unit 172, and the information bitrate I n A null (or null TLV packet) is inserted at the end as data to reconstruct the segmented frame as exemplified in Figure 7.

[0083] In this example, the number of slot divisions for reconstructing the divided frame shown in Figure 7 and the unique number indicating the basic divided slot corresponding to each transmitter 12 are used as identification information that can at least identify the type and number of transmission lines used for the bulk transmission, as TMCC information (TMCC1, TMCC2, ..., TMCC m ) is transmitted using the above. However, if the coding and modulation scheme used in multiple broadcast transmission lines is known in advance, and the number of data distributions to m transmitters 12 and IP network 19 is fixed and not variable, or if identification information is transmitted using MMT signals, or if it is scheduled or notified in advance between the transmitting device 11 and the receiving device 17 to be known in advance, the segmented frame reconstruction unit 171 will use the above TMCC information (TMCC1, TMCC2, ..., TMCC m Regardless of the method used, it is possible to reconstruct segmented frames that have a predetermined fixed frame length.

[0084] In other words, the segmented frame reconstruction unit 171, based on the predetermined identification information, determines the basic segmentation slots for the broadcast transmission path (two satellite transmission paths in this embodiment) and, if there is a signal of a TLV packet sequence via an IP line, the basic segmentation slots for the IP line, and reconstructs the segmented frame. This allows for accurate reconstruction of the segmented frame using nulls (or null TLV packets) that are not actually transmitted in the broadcast transmission path and communication transmission path, thereby maintaining a constant processing speed between each basic segmentation slot in each segmented frame and stabilizing processing. This makes it possible to compensate for transmission delays in the broadcast transmission path and communication transmission path, and enables bulk transmission in a manner highly compatible with both the broadcast transmission path and the communication transmission path.

[0085] In this manner, the segmented frame reconstruction unit 171 reconstructs the segmented frame as described above with reference to Figure 7.

[0086] Here, the segmented frame reconstruction unit 171 satisfies the condition that the delay difference between each transmission path (in this example, two satellite transmission paths and an IP line) is small enough that no signal order reordering error occurs on the receiving device 17 side, and allocates the maximum number of TLV packets for each corresponding transmission path to each basic segmented slot, or a fixed number predetermined between the transmitting device 11 and the receiving device 17. On the other hand, when configuring a transmission system 1a with a large delay difference between each transmission path, the segmented frame reconstruction unit 171 detects a TLV packet indicating the segmented frame number assigned on the transmitting device 11 side, and allocates this TLV packet as the TLV packet located at the beginning of each basic segmented slot #1, #m, to store the maximum number of TLV packets for each corresponding transmission path, or a fixed number predetermined between the transmitting device 11 and the receiving device 17. By referring to such segmented frame numbers, the delay difference can be corrected.

[0087] Furthermore, when information identifying the TLV packets stored in each basic division slot (information indicating which TLV packets, identifiable by which first and second signal source sequence numbers, are stored in which basic division slot in which division frame) is embedded in the free area of ​​the TMCC information obtained from the m transmitters 12, the division frame reconstruction unit 171 reconstructs the division slots by storing the corresponding TLV packets for each transmission path in each basic division slot according to the TMCC information. As a modification, the division frame reconstruction unit 171 may also be configured to reconstruct the division frame based on the received TLV transmission control signal when a TLV packet containing a TLV transmission control signal indicating the physical configuration of each IP data flow that can be associated with each TLV packet flow is being transmitted.

[0088] The flag detection unit 173 detects a flag that specifies transmission path switching added by the transmitting device 11 from the TLV packet (TLVP) sequence in each basic division slot of the division frame reconstructed by the division frame reconstruction unit 171, and outputs the position of the TLV packet with that flag on the division frame and the value of the flag to the output signal generation unit 174.

[0089] The output signal generation unit 174, based on the position and value of the flags on the divided frame detected by the flag detection unit 173, concatenates the TLV packet (TLVP) sequences within each basic divided slot to reconstruct the TLV stream and outputs it to the content redistribution unit 175.

[0090] Figure 9 shows an example of restoring a TLV stream using the flag detection unit 173 and output signal generation unit 174 in a receiving device 17 of one embodiment of the present invention, and corresponds to the embodiment of the transmitting device 11 shown in Figure 5(b) above. As shown in Figure 9, the flag detection unit 173 detects and refers to a flag that specifies transmission path switching, and can identify the sequence of TLV packet flows via the first and second satellite transmission paths (in the figure, TLV packets 4K_#1, 4K_#2, 4K_#3,…) that represent content data of 4K video signals transmitted using two satellite transmission paths with m=2 set by the output signal generation unit 174, and the sequence of TLV packet flows (in the figure, TLV packets IP_#1, IP_#2, IP_#3,…) that represent content data of AR video signals transmitted using an IP line, and can restore a single TLV stream shown in Figure 5(a) above in a manner that allows identification of content data (two types in this example: 4K video signals and AR video signals).

[0091] In particular, in this embodiment, when the receiving device 17 restores the TLV stream using the output signal generation unit 174, the flag detection unit 173 detects a flag that specifies transmission path switching added by the transmitting device 11, and the output signal generation unit 174 reads TLV packet sequences from the transmission path specified by the flag and organizes the output order until the next flag is detected. In this example, the flag detection unit 173 first detects a flag (Type=0x04) indicating IP line output, and the output signal generation unit 174 reads the TLV packet flow (in this example, sequences of five TLVPs) transmitted via the IP line until the next flag is detected. Subsequently, when the flag detection unit 173 detects a flag (Type=0x06) indicating second satellite transmission path output as the next flag, the output signal generation unit 174 reads the TLV packet flow (in this example, one TLVP at a time) transmitted via the second satellite transmission path until the next flag is detected. Next, the flag detection unit 173 detects a flag (Type=0x04) indicating IP line output as the next flag, and the output signal generation unit 174 reads the TLV packet flow transmitted via the IP line until the next flag is detected. By repeating this operation, the output signal generation unit 174 can restore the TLV stream in a manner that allows identification of the content data shown in Figure 5(a) corresponding to Figure 9.

[0092] The content redistribution unit 175 extracts IP packet data from the restored TLV stream, each of which is assigned a destination IP address, to constitute multiple content data. It then reconstructs the IP packet content and outputs it to the 4K decoder 18-1 and AR decoder 18-2 on the display device 18, which are the destinations corresponding to each destination IP address.

[0093] More specifically, in this embodiment, the TLV signal generation unit 112 in the transmitting device 11 is configured to remove the IP header indicating the destination IP address corresponding to each content data that constitutes the IP packet format content, extract the IP packet payload portion, and convert it into a TLV packet format signal for each type of content data. The content redistribution unit 175 then extracts the TLV packet payload for each content data from each TLV packet of the restored TLV stream obtained from the output signal generation unit 174. Subsequently, the content redistribution unit 175 uses the extracted TLV packet payload as the IP packet payload and generates a new IP packet format signal by adding an IP header indicating the destination IP address corresponding to each content data, using the destination IP address X indicating the content data of the 4K video signal and the destination IP address Y indicating the content data of the AR video signal, which are known between the transmitting device 11 and the receiving device 17. The content redistribution unit 175 then outputs to the destination devices (4K decoder 18-1 and AR decoder 18-2) on the display device 18 corresponding to each destination IP address. Alternatively, instead of the display device 18, a recording device that records large amounts of data onto a recording medium may be used.

[0094] In this way, the content redistribution unit 175 converts the TLV stream obtained from the output signal generation unit 174 into a first IP data flow to destination IP address X indicating content data of a 4K video signal corresponding to the 3D content from the content streamer 10a, and a second IP data flow to destination IP address Y indicating content data of an AR video signal, and distributes them to the 4K decoder 18-1 and AR decoder 18-2 on the display device 18 corresponding to their respective destination IP addresses. Each of the 4K decoder 18-1 and AR decoder 18-2 performs decoding processing on the display device 18 necessary to display the 3D content by combining the 4K video signal and the AR video signal (not shown).

[0095] Furthermore, the TLV signal generation unit 112 in the transmitting device 11 can be configured to convert the content data into TLV packet format signals for each type of content data while retaining the IP header indicating the destination IP address corresponding to each content data constituting the IP packet format content. In this way, when the IP packets constituting the IP signals for each type of content data from the content streamer 10a are stored as they are (including the IP header and IP packet payload) in the TLV packet payload, the content redistribution unit 175 extracts the TLV packet payload for each content data from each TLV packet of the TLV stream obtained from the output signal generation unit 174, thereby generating a 3D content signal (information bitrate I) in the same signal format as that transmitted from the content streamer 10a. all It is possible to reconstruct a signal equivalent to the one transmitted via [the specified method].

[0096] In this case, it is preferable that the content redistribution unit 175 has the function of verifying the signal order of each content data and rearranging it to the correct signal order if there is a discrepancy in the signal order. That is, in 3D content, each IP packet sequence in the first IP data flow for destination IP address X and the second IP data flow for destination IP address Y is assigned first and second signal source sequence numbers indicating the respective signal order, and furthermore, when MMT signals are configured, package information relating the first IP data flow and the second IP data flow is described. Using these, it is possible to configure the system to verify the signal order and rearrange it to the correct signal order if there is a discrepancy in the signal order.

[0097] (Examples of flags) Figure 10(a) shows an example of a TLV signal in which TLV packets for each content data, generated by the TLV signal generation unit 112 in a transmission device 11 of one embodiment of the present invention, are connected in a single stream. Figure 10(b) shows an example in which a flag specifying the transmission path switching of TLV packets is added by the flag addition unit 113 in a modified transmission device 11 of the present invention. Note that Figure 10(a) is the same as Figure 5(a), and the TLV signal generation unit 112, similar to the embodiment illustrated in Figure 5(a), constructs a TLV signal that makes up a single TLV stream for TLV packets (TLVPs) sequentially generated for each type of content data.

[0098] In this modified version shown in Figure 10(b), unlike the embodiment shown in Figure 5(b), the flag-adding unit 113 adds a flag to specify transmission path switching to the packet type field of the TLV header in the TLV packet immediately preceding the TLV packet for each transmission path to which it is output, for all TLV packets. For example, in this modified version shown in Figure 10(b), a TLV packet flow consisting of one or more consecutive TLV packets (TLVPs) representing content data of a 4K video signal (one TLVP at a time in this example) is transmitted across two satellite transmission paths with m=2, and a TLV packet flow consisting of one or more consecutive TLV packets representing content data of an AR video signal (a series of five TLVPs at a time in this example) is transmitted using an IP line. In this configuration, the flag to specify transmission path switching is added to the packet type field of the TLV header in the TLV packet immediately preceding the TLV packet for each transmission path to which it is output, for all TLV packets.

[0099] Furthermore, in the modified example shown in Figure 10(b), the flags specifying transmission path switching are preferably added to the packet type field of the target TLV packet by incrementing (or decrementing) from a predetermined value within the undefined range (in this example, "0x04 to 0xFD") for each transmission path (in this example, 3 paths: 2 satellite transmission paths and an IP line) to improve the accuracy of TLV stream reconstruction based on the detection of the flags on the receiving device 17 side. For example, the flag indicating IP line output is added as Type=0x04 to the packet type field of the target TLV packet, the flag indicating first satellite transmission path output is added as Type=0x05 to the packet type field of the target TLV packet, and the flag indicating second satellite transmission path output is added as Type=0x06 to the packet type field of the target TLV packet.

[0100] Therefore, in both the embodiment shown in Figure 5(b) and the modified example shown in Figure 10(b), the flag-adding unit 113 in the transmitting device 11 adds a flag specifying transmission path switching to at least the packet type field of the TLV header in the TLVP immediately before the transmission path switches (i.e., the TLVP immediately before the TLVP at the beginning of the TLV packet flow for each transmission path to be output). As a result, in both the embodiment shown in Figure 5(b) and the modified example shown in Figure 10(b), the receiving device 17 operates substantially the same way.

[0101] However, in the modified version shown in Figure 10(b), a flag specifying path switching is added to all TLV packets. This eliminates the need to "add a predetermined value (e.g., Type=0xFD) that is not used as a flag to specify path switching" as in the embodiment shown in Figure 5(b), effectively increasing the number of available paths by one. Furthermore, in this modified version, the receiving device 17 detects the flag from the TLV header of all TLV packets, allowing the "flag indicating path switching" to also be used for "identifying path maintenance," thus enabling efficient reconstruction of the TLV stream.

[0102] With the transmitter 11 and receiver 17 configured as described above (including modified versions), it becomes possible to perform bulk transmission of multiple types of content data constituting a single content in the bulk transmission method transmission system 1a. Furthermore, it becomes possible to reduce the signal jitter of the output of the transmitter 11 that occurs in this process, and it becomes possible to prevent image corruption due to memory overflow of the decoder or other devices downstream of the receiver 17.

[0103] Regarding the embodiments described above (including modified examples), a computer can be configured to function as a transmitting device 11 or a receiving device 17, and a program for enabling each means of the transmitting device 11 or the receiving device 17 can be suitably used. Specifically, a control unit for controlling each means can be configured as a central processing unit (CPU) within the computer, and a storage unit for appropriately storing the program necessary to operate each means can be configured as at least one memory. That is, by having the CPU execute the program in such a computer, the functions of each means described above can be realized. Furthermore, the program for enabling the functions of each means can be stored in a predetermined area of ​​the aforementioned storage unit (memory). Such a storage unit can be configured as RAM or ROM inside the device, or it can be configured as an external storage device (e.g., a hard disk). Also, such a program can be configured as part of software on the OS used by the computer (stored in ROM or an external storage device). Furthermore, the program for enabling each means to function can be recorded on a storage medium that the computer can read. Also, each of the means described above can be configured as part of hardware or software, and each can be combined to realize them.

[0104] Although the above-described embodiments are representative examples, it will be apparent to those skilled in the art that many modifications and substitutions are possible within the spirit and scope of the present invention. For example, the above-described embodiments describe a configuration in which a satellite transmission path of the ISDB-S3 transmission system is used as a broadcast transmission path, but it is also possible to use a configuration in which a next-generation 4K / 8K or similar terrestrial transmission path, which is expected to have a transmission frame configuration substantially similar to that of the ISDB-S3 system, is used as a broadcast transmission path. Furthermore, the above-described embodiments describe a configuration in which the transmitting device 11 and m transmitters 12 are provided separately, but it is also possible to provide a configuration in which m transmitters 12 are contained within the transmitting device 11. Therefore, the present invention should not be interpreted as being limited by the above-described embodiments, but rather limited only by the claims. [Industrial applicability]

[0105] According to the present invention, by specifying a transmission path for each type of content data that constitutes a single piece of content, it becomes possible to reduce signal jitter on the transmitting side and reliably prevent image distortion on the receiving side while enabling efficient bulk transmission. Therefore, it is useful for applications in bulk transmission systems that transmit large amounts of data, such as 3D content, by dividing it into separate transmission paths. [Explanation of Symbols]

[0106] 1,1a Transmission System 10 Signal source device 10a Content Streamer 11 Transmitter 12,12‐1,12‐2,…,12‐m transmitter 13, 13-1, 13-2, ..., 13-m transmitting antenna 14 Broadcasting Satellites 15 Receiving antenna 16, 16-1, 16-2, ..., 16-m receiver 17 Receiving device 18 Display device 18-1 4K Decoder 18-2 AR Decoder 19 IP Network 111 Content Distribution Department 112 TLV signal generation section 113 Flag Addition Section 114 Segmented Frame Generation Unit 115 IP Encapsulation Section 171 Segmented Frame Reconstruction Unit 172 IP Decapsulation Unit 173 Flag detection unit 174 Output signal generation unit 175 Content Redistribution Department

Claims

1. A transmitting device that uses multiple broadcast transmission lines to bulk transmit IP packet-formatted content in TLV (Type Length Value) packet format, A content distribution means that receives multiple content data, each of which is in IP packet format and has a destination IP address assigned to it, from a predetermined content streamer, identifies each destination IP address, determines the type of the multiple content data, and distributes them accordingly. A TLV signal generation means that converts IP packet signals, which are sorted according to the type of content data, into TLV packet signals for each type of content data, and constitutes a single TLV stream. A flag-adding means for determining a sequence of consecutive TLV packets for each type of content data in order to bulk transmit the TLV stream according to the type of content data, and adding a flag to the packet type field of the TLV header of a predetermined TLV packet in the TLV stream that specifies a transmission path switch identifiable on the receiving side, A segmented frame generation means that, based on identification information predetermined to at least identify the type and number of transmission paths used for the bulk transmission, determines segmented frames with a frame length conforming to a common transmission method for multiple broadcast transmission paths used for the bulk transmission, configures the segmented frame with a number of basic segmented slots corresponding to the multiple broadcast transmission paths when the information bitrate required for the transmission of the TLV stream fits within the maximum transmission rate of the multiple broadcast transmission paths, and adds a predetermined number of basic segmented slots for transmission via the IP network communication transmission path to configure the segmented frame when the information bitrate required for the transmission of the TLV stream exceeds the maximum transmission rate that can be transmitted by the multiple broadcast transmission paths, and controls the bulk transmission of the TLV stream according to the type of content data based on the segmented frame, A transmitting device characterized by comprising the following features.

2. The transmission device according to claim 1, characterized in that the flag-adding means is configured to add the flag to at least the packet type field of the TLV header in the TLV packet immediately before the transmission path switches.

3. The transmission device according to claim 2, characterized in that the flag-adding means is configured to add the flag to the packet type field of the target TLV packet by incrementing or decrementing it from a predetermined value within the range of an undefined area, for the number of transmission paths used for the bulk transmission.

4. A receiving device for receiving IP packet content transmitted in bulk by the transmitting device described in claim 1, A segmented frame reconstruction means identifies the structure of the segmented frame based on predetermined identification information, determines a predetermined number of basic segmented slots, and, according to the type of content data, assigns a sequence of TLV packets to the basic segmented slots corresponding to each transmission path in the order in which they were received, and reconstructs the segmented frame generated by the transmitting device. This means identifies the structure of the segmented frame based on predetermined identification information, determines a predetermined number of basic segmented slots, and, according to the type of content data, assigns a sequence of TLV packets to the basic segmented slots corresponding to each transmission path in the order in which they were received, and reconstructs the segmented frame generated by the transmitting device. A flag detection means for detecting the flag from the TLV packet sequence within each basic partitioning slot of the reconstructed partitioned frame, An output signal generation means that, based on the position and value of the flag on the detected segmented frame, concatenates the TLV packet sequences within each basic segmented slot to reconstruct the TLV stream, Content redistribution means extracts IP packet data from the restored TLV stream, each of which is assigned a destination IP address, and reconstructs each content data that constitutes the IP packet content, outputting it to the destination device corresponding to each destination IP address. A receiving device characterized by being equipped with the following features.

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