JP6220390B2 - Video data distributed transmission system - Google Patents

Description

  The present invention relates to a video data distributed transmission system for distributing and distributing video data for broadcasting, and in particular, the video data transmitting device divides the video data and assigns a packet alignment number to the packet. Large-capacity video data can be obtained even in a network environment where the bandwidth is limited by the video data receiving device arranging the packets transmitted in a distributed manner based on the sorting number and restoring the video data so that the video data can be viewed. In addition, the present invention relates to a video data distributed transmission system that guarantees the efficiency and high quality of data transmission with minimal fluctuation and loss of video.

  Conventionally, various technologies for distributing video used for television broadcasting and the like have been developed, and a video distribution system that takes into consideration high-quality video, distribution efficiency, availability, and reliability has been developed. ,It is used. In particular, high-volume, high-quality video data delivery requires high video quality assurance and reliability, and high transmission speed, so high quality, high reliability, and high-speed transmission are required. Development of a video data transmission system to be secured is underway.

  For example, Japanese Patent Application Laid-Open No. 2010-278799 exists as a technique related to a system for distributing and transmitting video data. Here, when a failure occurs on the path during data transmission and its transmission performance deteriorates, the transmitting side distributes data to all the transmission paths toward the receiving side, and the receiving side distributes multiple data. The technology that selects the data that arrives first among the transmitted data and performs reception processing is disclosed, and a failure occurred on the transmission path in data transmission using wireless transmission of high-definition video Even in this case, it has been suggested that degradation of video quality can be reduced.

  In the above technique, data combining processing is performed when data is received by the receiving side, but a sequence number added to data is used for data alignment that is essential before data combining. However, in order to maintain the high quality of video data, a function to correct data errors is indispensable. However, in the above technology, there is no mention of redundant data for data correction, and the quality of video is maintained. However, the video data transmission system is inadequate, and there is a problem in that it cannot be a video data transmission system in which a sufficient quality is ensured with a reduced delay when delivering high-quality live video. Further, since the system does not consider the bandwidth of each transmission path for distributed transmission, there is a problem that it is not suitable for transmission of high-quality and large-capacity data.

  Japanese Unexamined Patent Application Publication No. 2009-244308 exists as a technique related to a system for transmitting video data. Here, a technique for distributing video data corresponding to a part of a hierarchy of a video file that is hierarchically encoded based on a network throughput value is disclosed. In addition, it is possible to view high-quality video content as necessary, and a technique for switching them seamlessly to the maximum without the user's awareness is disclosed.

  However, from the viewpoint of video distribution reliability, the above technology is not sufficient for maintaining video quality, especially for video distribution for real-time television broadcasting that requires high quality and high reliability. In order to do so, there was a problem that a system with sufficient reliability could not be obtained. Further, in an environment where the bandwidth of the transmission path is limited, it is impossible to distribute high-quality video content, and there is a problem that it is not suitable for transmitting high-quality large-capacity data.

Therefore, high-quality video data can be transmitted without delay even in an environment where the bandwidth of the transmission path is limited while ensuring high-quality video data, efficient delivery, and reliability during data delivery. Development of a system related to transmission of certain video data has been desired.
JP 2010-278799 A JP 2009-244308 A

  The present invention relates to a video data distributed transmission system for distributing and distributing video data for broadcasting. In particular, the video data transmitting apparatus divides the video data and assigns packet alignment numbers to the packets. The video data receiving device arranges the packets transmitted in a distributed manner based on the sorting number and restores the video data so that the video data can be viewed. It is an object of the present invention to provide a video data distributed transmission system that can deliver video data and that can minimize the fluctuation and loss of video and ensure the efficiency and high quality of data transmission.

In order to achieve the above object, the video data distributed transmission system according to the present invention receives video data and converts it into a transport stream (TS) format or a transport stream with a time stamp (TTS) format. A video data transmitting apparatus that transmits the video data encoded by the encoding means to an IP network, a video data receiving apparatus that receives the video data transmitted from the video data transmitting apparatus, and the video data receiving apparatus. A video data distributed transmission system for performing high-speed video data transmission via an IP network comprising decoding means for decoding received video data, wherein the video data transmitting device is distributed over a plurality of paths In TS format or TTS format for transmission Transmission packet generation means for dividing the data into TS packets or TTS packets and FEC (Forward Error Correction) packets, and the packets divided and generated by the transmission packet generation means are sequentially distributed and transmitted to the IP network. transmission means comprising a plurality, Tona is, the transmission packet generating means, the data of the TS format or TTS format received from said encoding means via a single or two ports in the TS packet or TTS packets and FEC packets A packet dividing means for dividing, a sorting number assigning means for identifying a packet type and assigning a sequence number of the TS packet or TTS packet immediately divided by the packet dividing means to the FEC packet; a TS packet or Is composed of transmission packet distribution means for distributing TTS packets and FEC packets to one or a plurality of transmission means .

  The encoding means receives the generated TS packet or TTS packet through one port and the generated FEC packet through another port, thereby receiving video data in TS format or TTS format in the video data transmitting apparatus. It is a configuration to pass.

  The transmission means sequentially selects a path to be used for transmission from a plurality of paths, and sends the TS packet or TTS packet and FEC packet generated by the transmission packet generation means to the IP network. It is a configuration.

  In addition, the video data receiving apparatus is arranged by a receiving unit that receives the packets distributed and transmitted by the transmitting unit, an alignment storing unit that aligns the packets received by the receiving unit, and the alignment storing unit. Video data restoration means for integrating TS packets or TTS packets and FEC packets into a viewable format and transmitting them to a decoding means.

  The alignment storing means includes a packet aligning means for aligning the TS packets or TTS packets and FEC packets received by the receiving means in the order of the sequence number of each packet and for each packet type; A first storage means comprising a first buffer area for temporarily storing TTS packets, a second storage means comprising a second buffer area for temporarily storing FEC packets, and packets sorted by the packet sorting means are classified by type. The buffering means stores data in one buffer area or the second buffer area.

  Further, the video data restoring means includes a restored data selecting means for selecting each TS packet or TTS packet and FEC packet temporarily stored in the buffer by the buffering means after a predetermined time, and an aligned TS packet. Alternatively, when the sequence number of the TTS packet matches the sequence number of the FEC packet given by the sorting number assigning means, the FEC packet is inserted (arranged) after the TS packet or TTS packet and the FEC is inserted. This is composed of packet integration means for deleting the sequence number assigned to the packet.

In addition, the video data transmitting apparatus includes a transmission schedule adjusting unit that monitors and adjusts packet transmission processing by the transmitting unit.
Further, the video data transmitting apparatus is provided with a division control means for monitoring and controlling the packet division processing by the packet division means.

In addition, the video data receiving apparatus is provided with an integrated control unit that monitors and controls packet integration processing by the packet integration unit.
Further, the video data transmitting apparatus is provided with a band securing means for securing a band for video distribution.

  In addition, the video data distributed transmission system transmits and / or receives TS format data or TTS format data to the IP network via SIP, so that the video data transmitting device and the video data receiving device are separately provided. A relay device that is equipped and receives the video data transmitted from the video data transmitting device and transmits it to the IP network, and receives the video data transmitted from the IP network and delivers it to the video data receiving device. Session establishment means for establishing a SIP session in response to a session establishment request, session management means for monitoring and controlling the established session, and session disconnection means for disconnecting the established session in response to the request, The relay device uses the session establishing means to In response to an unacceptable response to the session establishment request, an error response is made without performing the backward operation, the session establishment request is resumed, and the session is disconnected by the session disconnection means without waiting for a response to the session disconnection request. .

In addition, the relay device is configured to include a bandwidth securing unit that secures a bandwidth for video distribution including a bandwidth of 15 Mbps to 25 Mbps .
The IP network is composed of an NGN (Next Generation Network), and a path used for transmitting TS format data or TTS format data is a path secured on the NGN.

Further, the bandwidth securing means is configured to have a bandwidth of 15 Mbps to 25 Mbps.
Further, the video data transmission device is configured to perform streaming transmission of video data using RTP under session management by RTCP.

Since the present invention is configured as described in detail above, the following effects are obtained.
1. Since video data in transport stream (TS) format or transport stream with time stamp (TTS) format is transmitted to the IP network, general-purpose data transmission in accordance with communication standards can be realized. No further conversion of the data format for the device is required. In addition, since the video data transmission device divides the video data into TS packets or TTS packets and FEC packets by the transmission packet generation means and sequentially transmits them to the IP network, the video data is distributed to a plurality of routes for each packet. Can be sent. In addition, since the transmission packet generation means is provided with an alignment number assigning means for assigning the sequence number of the TS packet or TTS packet that has been divided immediately before to the FEC packet, the FEC packet is inserted at an appropriate position when the packets are integrated. Packet alignment is facilitated.

2. Since the TS packet generated by the encoding means or the TTS packet and the FEC packet can be delivered to the video data transmitting apparatus via separate ports, a video data distributed transmission system that can support any transmission form is provided. It can be configured.
3. The transmission means selects a route to be used for transmission from a plurality of routes in order, and sends the divided packets to the IP network. Is possible.

4). The video data receiving apparatus receives and arranges the distributedly transmitted packets, and converts the distributedly transmitted video data into a format that can be used quickly and easily in order to integrate them into a format that can be viewed by the video data restoration means. It becomes possible.
5). Since the arrangement storage means arranges the packets received by the reception means in the sequence of the sequence numbers in the first buffer area and the second buffer area for each packet type, the buffering means performs buffering. Alignment and integration is easy and quick.

6). Since the packet integration means is configured to insert the FEC packet when the sequence number of the aligned TS packet or TTS packet and the sequence number of the FEC packet coincide with each other, accurate integration of packets distributed and transmitted easily Is possible.
7). Since the video data transmission apparatus is provided with transmission schedule adjustment means for monitoring and adjusting packet transmission processing by the transmission means, the transmission of each packet is stabilized, and highly reliable video data can be distributed and transmitted.

8). Since the video data transmission apparatus is provided with a division control means for monitoring and controlling the packet division processing by the packet division means, data loss or damage during packet division can be prevented, and smooth packet division processing can be realized. .
9. The video data receiver is equipped with an integrated control unit that monitors and controls packet integration processing by the packet integration unit, so that errors during packet integration can be avoided and eliminated, and stable video data restoration is possible. It becomes.

10. Since the video data transmitting apparatus is provided with a band securing means for securing a band for video distribution, stable video data can be transmitted and received by band-guaranteed communication using a specific band.
11. A relay device that transmits and receives video data is installed separately in the video data transmission device and the video data reception device, establishes a session using the SIP protocol, monitors and controls the established session, and responds to requests. Since the session is disconnected, stable video data transmission / reception is possible. In addition, since video data is transmitted / received to / from the IP network via SIP, inexpensive and stable video data can be transmitted / received using the existing communication network. In addition, when the session transmission request is unacceptable, the session establishment means sends an error response and resumes the session establishment request, and the session disconnection means disconnects the session without waiting for a response to the session disconnection request. Therefore, it is possible to ensure the continuity of the video data and increase the transmission efficiency of the video data.

12 Since the relay device is provided with the band securing means for securing the video distribution band, even when the relay device is used, stable video data transmission / reception by band-guaranteed communication using a specific band becomes possible. Further, since the bandwidth secured by the bandwidth securing means is set to 15 Mbps to 25 Mbps, stable high-speed data transmission is possible.
13. Since NGN is used as the IP network, band-guaranteed data transmission is possible, and stable and high-speed data transmission can be realized.

14 Since the relay device performs streaming transmission of video data by RTP by session management by RTCP, it is possible to transmit video data with higher stability.

  Hereinafter, a video data distributed transmission system according to the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a schematic diagram of a video data distributed delivery system according to the present invention, and FIG. 2 is a schematic diagram of a transmission packet generation means. FIG. 3 is a flowchart of processing by the transmission packet generation unit, and FIG. 4 is a conceptual diagram showing packet processing by the transmission packet generation unit. FIG. 5 is a schematic diagram of transmission packet generation means when there are a plurality of ports for receiving packets, and FIG. 6a is a flowchart of TS or TTS packet processing by the transmission packet generation means. FIG. 6B is a flowchart of FEC packet processing by the transmission packet generation unit, and FIG. 7 is a conceptual diagram showing packet processing by the transmission packet generation unit when there are a plurality of ports that receive packets.

  FIG. 8 is a schematic diagram of the alignment storage unit and the video data restoration unit, and FIG. 9A is a flowchart of TS or TTS packet processing by the alignment storage unit and the buffering unit. FIG. 9b is a flowchart of FEC packet processing by the alignment storage unit and the buffering unit, and FIG. 10 is a flowchart of packet processing by the video data restoration unit. FIG. 11 is a conceptual diagram showing packet processing by the video data restoration means, and FIG. 12 is a schematic diagram of a video data distributed delivery system using relay devices.

  As shown in FIG. 1, the video data distributed transmission system according to the present invention includes a video data transmission apparatus 100 including an encoding unit 110, a transmission packet generation unit 120, and a transmission unit 130, a reception unit 230, and an alignment storage unit 240. And a video data receiving device 200 comprising a video data restoring means 220 and a decoding means 210, which are mainly used for high-speed distributed transmission of the video data 500 via the IP network 400.

  As shown in FIG. 1, the encoding unit 110 is a unit for converting video data 500 transmitted from the outside into a format that can be transmitted on the IP network 400. In the present embodiment, the encoding means 110 that has received the video data 500 converts the video data 500 into MPEG-2, and here, in particular, with a transport stream (TS) format (MPEG-2 TS) or a time stamp. Convert to Transport Stream (TTS) format. The video data 500 whose data format has been converted is sent to the video data transmitting apparatus 100.

  The video data transmitting apparatus 100 is an apparatus that distributes and transmits the video data 500 converted into the TS format or the TTS format by the encoding unit 110 via a single port or a plurality of ports. As will be described later, the video data transmitting apparatus 100 divides the video data 500 into packets and transmits the packets through a plurality of lines provided in the IP network 400 limited to a narrow band. Thereby, even in a low bit rate environment in which the bandwidth in digital transmission is limited and the data transmission speed is limited, large-capacity data such as video data can be transmitted at a high speed.

As shown in FIG. 1, the video data transmission apparatus 100 includes a transmission packet generation unit 120 and a transmission unit 130.
The transmission packet generation unit 120 converts the video data 500 converted into the TS format or the TTS format by the encoding unit 110 into the TS packet, the TTS packet, and the FEC packet in order to distribute and transmit the video data 500 to a plurality of paths. It is means for dividing.

  The transmission unit 130 is a unit that transmits the video data 500 from the video data transmission device 100 installed on the transmission side. The transmission unit 130 is a unit that sequentially distributes the packets generated by dividing the video data 500 by the transmission packet generation unit 120 to the IP network 400 and transmits the packets to the video data transmission apparatus 100. Transmission means 130 is provided. The transmission means 130 is composed of a storage area for sequentially storing assigned packets, and is controlled so as to sequentially transmit the packets to the IP network 400.

  The transmission unit 130 can be configured to perform packet transmission while synchronizing with other transmission units 130 at the time of packet transmission. As a result, packet delay can be minimized, video provision delay can be suppressed, and video data transmission efficiency can be improved.

  In this embodiment, as shown in FIG. 1, the number of transmission means 130 corresponding to the number of lines for distributed transmission is provided, and the number of ports used for data transmission is single or plural depending on the number of lines. However, the present invention is not limited to this configuration, and a configuration may be adopted in which a single port is shared by a plurality of transmission units 130 to control packet transmission. In this embodiment, 1 to 10 transmission units 130 can be provided, but the present invention is not limited to this.

  The video data receiving device 200 is a device that receives the video data 500 distributed from the video data transmitting device 100 and transmitted to the IP network 400. Since the video data 500 transmitted through the IP network 400 is subjected to the division process, the arrival order of the divided packets may be reversed depending on the situation of the IP network 400. As will be described later, the video data receiving apparatus 200 has a function of connecting packets after arranging them in order, so that the quality of the video data 500 can be maintained even when the arrival order of the packets is reversed. Is possible.

  The video data 500 received by the video data receiving apparatus 200 and aligned and connected is transmitted to the decoding means 210. The decoding unit 210 is a unit that converts the video data 500 received, aligned and connected by the video data receiving apparatus 200 into a viewable format.

As shown in FIG. 1, the video data receiving apparatus 200 includes a receiving unit 230, an alignment storage unit 240, and a video data restoration unit 220.
The reception unit 230 is a unit that receives the video data 500 divided into packet units that are sequentially transmitted from the transmission unit 130 of the video data transmission apparatus 100 to the IP network 400. The video data reception apparatus 200 includes a single unit. Alternatively, a plurality of receiving means 230 are provided. The receiving unit 230 includes a storage area for sequentially storing packets received via the IP network 400.

  When a single receiving unit 230 is provided in the video data receiving apparatus 200, it is desirable that the receiving unit 230 has a storage area corresponding to the transmitting unit 130. The receiving unit 230 receives the packets transmitted in synchronization with each transmitting unit 130 and accumulates them in the corresponding storage area. Then, the receiving unit 230 further collects the packets for each TS packet, TTS packet, and FEC packet, and sequentially stores each packet. It transmits to the alignment preservation | save means 240. FIG.

  Further, when a plurality of receiving means 230 are provided in the video data receiving apparatus 200, each receiving means 230 has a storage area and receives a packet transmitted while synchronizing with the corresponding transmitting means 130. After accumulating in the storage area, the packets are collected for each TS packet, TTS packet, and FEC packet in a separate storage area, and each packet is sequentially transmitted to the alignment storage unit 240.

  The video data 500 received by the receiving unit 230 is transmitted to the alignment storage unit 240. The alignment storage unit 240 is controlled so as to align the packets received by the reception unit 230 and grouped together into TS packets, TTS packets, and FEC packets based on the sequence information attached to the packets. .

  The video data 500 aligned by the alignment storage unit 240 is transmitted to the video data restoration unit 220. The video data restoration unit 220 is a decoding unit that integrates TS packets or TTS packets and FEC packets, which are divided packets constituting the video data 500 and arranged by the reception unit 230, into a viewable data format. 210.

  The video data 500 encoded by the encoding means 110 is transmitted to the video data transmitting apparatus 100. At this time, the generated TS packet or TTS packet constituting the video data 500 and the generated FEC packet are the same port. The video data is transmitted to the video data transmitting apparatus 100. The generated TS packet or TTS packet may be sent through one port, but the TS packet or TTS packet and the FEC packet may be transmitted to the video data transmitting apparatus 100 via different ports. . These can be arbitrarily selected, and the video data in the TS format or the TTS format can be transferred to the video data transmitting apparatus with any configuration.

Next, the transmission packet generator 120 will be described in detail.
As shown in FIG. 2 or 5, the transmission packet generation unit 120 includes a packet division unit 122, an alignment number assigning unit 124, and a transmission packet distribution unit 126, and divides the video data 500 into packets. To the transmission means. The packet dividing unit 122 is a unit that divides TS format or TTS format data received from the encoding unit 110 via a single port or two ports into TS packets, TTS packets, and FEC packets.

  When the video data 500 is converted into the TS format or the TTS format by the encoding unit 110, an FEC packet that is redundant data for restoring data is generated by the encoding unit 110 at the same time when data corruption or loss occurs. Each of the generated data is transmitted to the packet dividing unit 122, and division processing is performed.

  Note that the transmission form from the encoding means 110 may be the case where data in the TS format or TTS format and the FEC packet pass through the same port, or through a different port. In the present embodiment, the transmission packet generation means 120 has the configuration shown in FIG. 2 when the same port is used, so that any data transmission mode can be supported. The configuration is as shown in FIG.

  As shown in FIGS. 2 and 5, among the data divided and arranged by the packet dividing unit 122, the FEC packet is processed by the alignment number assigning unit 124. Each TS packet or TTS packet and FEC packet holds a unique sequence number as data. The sequence number assigning means 124 uses this sequence number. That is, as shown in FIG. 3 and FIG. 6B, the sorting number assigning unit 124 is a unit that determines the type of packet and sets only the FEC packet as an operation target, and is an FEC that is an operation (processing) target. Processing for adding a sequence number of a TS packet or TTS packet (an FEC packet aligned immediately before a TS packet or TTS packet) that has been subjected to the division processing immediately before the division processing by the packet division unit 122 for the FEC packet to the packet Is done.

  As shown in FIG. 2, when TS format or TTS format data and the FEC packet are transmitted through the same port, as shown in FIG. 3, the alignment number assigning means 124 first determines the packet type. In the case of an FEC packet, as shown in FIG. 4, the TS packet or the sequence number of the TTS packet aligned immediately before the FEC packet is added to the FEC packet and transmitted to the transmission packet sorting unit 126. To do. If it is a TS packet or a TTS packet, it is transmitted to the transmission packet sorting means 126 without being processed.

  Also, as shown in FIG. 5, when TS format or TTS format data and FEC packets are transmitted via different ports, there is no need to determine the packet type, and from the port where the TS packet or TTS packet is transmitted. As shown in FIG. 6a, the received packet is directly transmitted to the transmission packet sorting unit 126 without being processed. On the other hand, as shown in FIG. 6B, the sorting number assigning means 124 sends the packets received from the port to which the FEC packet is transmitted to the position immediately before the FEC packet. The sequence number of the TTS packet is extracted, added to the FEC packet (see FIG. 7), and transmitted to the transmission packet sorting unit 126.

  In this way, by adding the TS packet or the sequence number of the TTS packet to the FEC packet, it becomes possible to improve the efficiency and accuracy at the time of integration of the separately transmitted packets, and transmission of higher quality video data can be achieved. It becomes possible. Note that the integration processing of the divided and transmitted packets will be described later.

  The divided TS packet or TTS packet and the FEC packet to which the sequence number is added are transmitted to the transmission packet sorting unit 126 as shown in FIG. The transmission packet distribution unit 126 is a unit that distributes TS packets or TTS packets and FEC packets to one or more transmission units 130.

  As shown in FIGS. 3 and 6b, the transmission packet distribution unit 126 equally distributes TS packets or TTS packets to the plurality of transmission units 130 based on the sequence numbers held by the TS packet, the TTS packet, and the FEC packet. And processing for distributing the FEC packet. Receiving each packet, the transmission means 130 sequentially performs a process of sending the packet to the IP network 400.

In this embodiment, the streaming delivery is performed using the RTP protocol. That is, the TS packet or the TTS packet is configured to be stored in the RTP packet using RTP. The RTP packet is further provided with an IP header to form an IP packet, and is sent to the IP network 400. With this configuration, more efficient data transmission can be realized. In this case, the number assigned to the FEC packet by the sorting number assigning unit 124 is the RTP sequence number of the RTP packet. The number used for the distribution process in the transmission packet distribution unit 126 is also an RTP sequence number.
Further, in order to increase the efficiency of the transmission process, it is desirable that the FEC packet has a packet length to which redundant data is further added so as to have the same size as the RTP packet or the IP packet.

  The transmission means 130 sequentially selects a path to be used for packet transmission from among a plurality of paths, and sends the TS packet or TTS packet and FEC packet generated by the transmission packet generation means 120 to the IP network 400. It is the composition to do. Since the transmission unit 130 itself can select a path to be used for packet transmission, the risk of packet loss and delay can be reduced, so that high-quality video data can be transmitted. In particular, as an embodiment of the present invention, when a single transmission unit 130 is used, it is desirable that the transmission unit 130 itself selects a path to be used for packet transmission.

Next, the alignment storage unit 240 will be described in detail.
The alignment storing unit 240 is a unit that restores the distributedly transmitted TS packet or TTS packet and FEC packet received by the receiving unit 230 to the state before the division, and as shown in FIG. The first storage unit 244a, the second storage unit 244b, and the buffering unit 246 are included.
The packet aligning unit 242 receives the data received by a single or a plurality of receiving units 230, and summarizes the data collected for each TS packet, TTS packet, and FEC packet, for each packet type, as shown in FIGS. 9a and 9b. It is means for arranging in order of sequence number based on the sequence number held by the packet.

  The first storage unit 244a is a unit for temporarily storing the aligned TS packets or TTS packets, and includes a first buffer area as a storage area. The second storage unit 244b is a unit for temporarily storing the aligned FEC packets, and includes a second buffer area as a storage area.

  The TS packet or the TTS packet and the FEC packet that have been sorted for each packet type by the packet sorting unit 242 are transmitted to the buffering unit 246. As shown in FIGS. 9a and 9b, the buffering means 246 is a means for storing the packets aligned by the packet alignment means 242 in the first buffer area or the second buffer area for each packet type. That is, the buffering means 246 determines the type of packet to be transmitted, and if it is a TS packet or a TTS packet, as shown in FIG. 9a, delivers the packet to the first storage means 244a, and if it is an FEC packet, As shown in FIG. 9b, the packet is delivered to the second storage means 244b.

Next, the video data restoration unit 220 will be described in detail.
The video data 500 (TS packet or TTS packet and FEC packet) stored in the first storage unit 244a and the second storage unit 244b is transmitted to the video data restoration unit 220. The video data restoring unit 220 is a unit for restoring the data so that the video data 500 divided into packets can be sent to the decoding unit 210 and changed to a viewable format. And integration means 224.

  As shown in FIG. 8, the restoration data selection unit 222 selects the TS packet or the TTS packet and the FEC packet temporarily stored in the first storage unit 244a and the second storage unit 244b by the buffering unit 246 after an arbitrary time has elapsed. It is means to take out by each. TS packets or TTS packets are continuously transmitted and sequentially stored in the first buffer area, which is the first storage means 244a. The time that can be stored in the buffer area can be set in advance. As shown in FIG. 10, a packet that has exceeded the set time is calculated retroactively from the latest TTS sequence number (overflowed from the buffer value). Packet) is selected for transmission to the decoding means 210. At the same time, a packet which is calculated retroactively from the latest FEC sequence number and exceeds the set time is selected as an object to be transmitted to the decoding unit 210 in the same manner.

  The packet integration unit 224 compares the sequence number of the TS packet or TTS packet that has been aligned and transmitted to the decoding unit 210 with the sequence number of the FEC packet that has been added by the alignment number assigning unit 124, and matches the sequence number. The FEC packet is inserted after the TS packet or the TTS packet, and the sequence number given to the FEC packet is deleted.

  As shown in FIG. 10, the TS packet or TTS packet selected by the restoration data selection unit 222 is transmitted to the decoding unit 210. At this time, as shown in FIG. 11, the sequence number assigned to the selected FEC packet is compared with the sequence number of the TS packet or TTS packet, and if they match, the sequence number assigned to the FEC packet is deleted. The FEC packet is transmitted to the decoding unit 210. By repeating this process, TS packets or TTS packets are transmitted to the decoding unit 210 in the correct order, and the FEC packet is restored to the correct position.

  By performing this process, a delay or the like occurs in the IP network 400, and it is possible to prevent a situation in which the FEC packet is not inserted at the correct position by changing the arrival order of the packets. Even when the strength of the FEC packet (FEC packet data restoration performance) is changed, it is not necessary to change the specifications of the system itself, and the system can be operated flexibly.

  As described above, by adopting a configuration in which the video data 500 is distributed and transmitted over a plurality of paths, it is possible to distribute a large amount of video data even in a network environment in which the bandwidth is limited. In addition, even when packet loss or delay occurs, it is possible to reliably restore packets using redundant data, and to minimize data fluctuations and loss and improve data transmission efficiency and high performance. It is possible to configure a video data distributed transmission system that guarantees quality.

  In this embodiment, the TS packet or TTS packet uses RTP and is stored in the RTP packet. The number assigned to the FEC packet by the sorting number assigning unit 124 is the RTP included in the RTP packet. It is a sequence number. Therefore, the packet stored in the first storage unit 244a and the packet transmitted to the decoding unit 210 are RTP packets and are transmitted to the decoding unit 210 as an RTP stream.

  As shown in FIG. 1, the video data transmitting apparatus 100 can be configured to include a transmission schedule adjusting unit 140. The transmission schedule adjustment unit 140 is a unit for monitoring and adjusting packet transmission processing by the transmission unit 130. When an abnormality is recognized in the packet transmission, control is performed so that the retraction operation is performed. If there is a problem on the IP network 400, processing such as changing the transmission path is performed. As a result, it is possible to stabilize packet transmission via the IP network 400 and to perform stable distributed transmission processing of the video data 500.

  Further, as shown in FIG. 1, the video data transmitting apparatus 100 can be configured to include a division control unit 150. The division control unit 150 is a unit for monitoring and controlling the packet division processing by the packet division unit 122. As a result, when an abnormality is recognized in the packet division processing, stable transmission processing of the video data 500 can be performed by performing control so that the retraction operation is performed.

  Also, the video data receiving apparatus 200 can be configured to include an integrated control means 250 as shown in FIG. The integration control means 250 is a means for monitoring and controlling the packet integration processing by the packet integration means 224. Thereby, when an abnormality is recognized in the packet integration processing by the packet integration means 224, stable transmission processing of the video data 500 can be performed by controlling to perform the retraction operation.

  Further, as shown in FIG. 1, the video data transmitting apparatus 100 can be configured to include a bandwidth securing unit 160 for securing a bandwidth for video distribution. Band securing means 160 is means for securing a band for transmission of video data 500 in IP network 400. Based on the number of bands used for transmitting the video data 500 (TS packet or TTS packet and FEC packet) registered in advance, the band securing unit 160 secures the band. Thereby, stable transmission of the video data 500 becomes possible. Note that, when a best effort network such as the Internet is used, it is difficult to secure a bandwidth because of its specifications. Therefore, it is desirable to use a bandwidth guaranteed network in which QoS is realized.

  The video data distributed transmission system according to the present invention can be configured to provide the relay device 300 and transmit and / or receive TS format data or TTS format data to the IP network via SIP. Hereinafter, the relay device 300 that performs transmission control using the SIP protocol will be described in detail.

  As shown in FIG. 12, the relay device 300 is separately provided in the video data transmitting device 100 and the video data receiving device 200, and the video data 500 (TS packet or TTS packet and FEC packet) is transmitted to the IP network 400, and the video data 500 transmitted from the IP network 400 is received and delivered to the video data receiver 200. The session establishing means 310, A session management unit 320 and a session disconnection unit 330 are included.

  The session establishing means 310 is transmitted via the IP network 400 by the transmission side relay device 300a issuing a SIP session establishment request and the reception side relay device 300b issuing a status code (acceptance response) accordingly. The SIP session is established between both relay devices 300.

  The session management unit 320 monitors and controls the state of the established session. As a session management protocol, in the embodiment of the present invention, session management using RTP and RTCP is performed. However, the present invention is not limited to this, and session management using SDP, for example, is also possible. .

  In addition, the session disconnection unit 330 performs a disconnection process on the session established by the session establishment unit 310 in response to a request from the relay device 300.

  In response to the SIP session establishment request from the transmission side relay device 300a, the session establishment unit 310 automatically receives the SIP session establishment request, and the reception side relay device 300b automatically responds with a status code (acceptance response). The SIP session between both relay devices 300 can be established. As a result, everything from the transmission to the reception of the video data 500 is automatically performed, and it is possible to realize the quick and efficient transmission and reception of the video data.

  When the session establishing means 310 is operated, the relay device 300 receives an unacceptable (reject) response from the receiving relay device 300b in response to the session establishment request from the transmitting relay device 300a. Is configured to perform an error response and resume the session establishment request. Normally, if an unacceptable (rejected) response is made, it may be possible to respond to the change to regressive operation, but by performing the processing as described above, quick switching of session establishment requests to other transmission routes Thus, the transmission efficiency of the video data 500 can be increased.

  In addition, when the session is disconnected, the session is disconnected without waiting for a session end response from the receiving relay device 300b in response to a session disconnection request from the session disconnecting device 330 from the transmitting relay device 300a. Such unilateral disconnection can eliminate the response waiting time, so that the continuity of the video data 500 can be secured and the transmission efficiency of the video data 500 can be increased.

  As shown in FIG. 12, the relay device 300 can be configured to include a bandwidth securing unit 340. Band securing means 340 is means for securing a band for transmission of video data 500 in IP network 400. Based on the number of bands used for transmitting the video data 500 (TS packet or TTS packet and FEC packet) registered in the relay device 300 in advance, the band securing unit 340 secures the band. Thereby, stable transmission of the video data 500 becomes possible. Note that, when a best effort network such as the Internet is used, it is difficult to secure a bandwidth because of its specifications. Therefore, it is desirable to use a bandwidth guaranteed network in which QoS is realized. Further, the bandwidth securing unit 160 provided in the video data transmission device 100 may be configured to function as a spare device when a failure occurs.

  In the present embodiment, the IP network 400 includes an NGN (Next Generation Network). NGN is a bandwidth-guaranteed network, unlike the normal Internet, which is a best-effort network. Accordingly, it is possible to easily secure the bandwidth. The band used by the video data distributed transmission system of the present invention for transmitting the video data 500 is a band secured by the bandwidth securing unit 160 or the bandwidth securing unit 340 on the NGN, so that stable transmission of the video data 500 is possible. In addition, it is possible to construct a distributed video data transmission system that is superior in cost performance.

  In the embodiment of the present invention, the bandwidth securing unit 160 or the bandwidth securing unit 340 secures a bandwidth of 10 Mbps to 25 Mbps. A bandwidth of 10 Mbps to 25 Mbps is appropriate as a band, and a video data distributed transmission system that is excellent in terms of performance can be obtained.

  In this embodiment, the video data transmitting apparatus 100 can be configured to perform session management using RTP and RTCP. That is, it is configured to perform streaming transmission of video data using RTP under session management by RTCP. By using this protocol, it is possible to efficiently transmit the video data 500 and to achieve a highly versatile video data distributed transmission system.

  Note that the video data distributed delivery system according to the present invention is configured to be able to send data of the same content to a plurality of routes without dividing each packet and performing distributed transmission. With this configuration, although the transmission speed is limited, it is possible to use one as a main stream and the other as a spare stream, and use a spare stream even if a problem occurs in the data transmission path. Thus, stable transmission of the video data 500 becomes possible.

Schematic diagram of video data distribution and delivery system according to the present invention Schematic diagram of transmission packet generation means Flow chart of processing by transmission packet generation means Conceptual diagram showing packet processing by transmission packet generation means Schematic diagram of transmission packet generation means when there are multiple ports to receive packets Flow chart of TS or TTS packet processing by transmission packet generation means Flow chart of FEC packet processing by transmission packet generation means Conceptual diagram showing packet processing by transmission packet generation means when there are a plurality of ports for receiving packets Schematic diagram of alignment storage means and video data restoration means Flow chart of TS or TTS packet processing by alignment storage means and buffering means Flow chart of FEC packet processing by alignment storage means and buffering means Flow chart of packet processing by video data restoration means Conceptual diagram showing packet processing by video data restoration means Schematic diagram of distributed video data distribution system using relay equipment

DESCRIPTION OF SYMBOLS 100 Video data transmission apparatus 110 Encoding means 120 Transmission packet generation means 122 Packet division means 124 Sorting number assignment means 126 Transmission packet distribution means 130 Transmission means 140 Transmission schedule adjustment means 150 Division control means 160 Band securing means 200 Video data reception apparatus 210 Decoding means 220 Video data restoration means 222 Restored data selection means 224 Packet integration means 230 Receiving means 240 Alignment storage means 242 Packet alignment means 244a First storage means 244b Second storage means 246 Buffering means 250 Integration control means 300 Relay device 300a Transmission side relay device 300b Reception side relay device 310 Session establishment means 320 Session management means 330 Session disconnection means 340 Band securing means 400 IP network 500 Video data

Claims (14)

Encoding means for receiving video data and converting it into a transport stream (TS) format or a transport stream with time stamp (TTS) format, and a video for transmitting the video data encoded by the encoding means to an IP network Via an IP network comprising a data transmitting device, a video data receiving device that receives video data transmitted from the video data transmitting device, and a decoding means that decodes video data received by the video data receiving device In a video data distributed transmission system for high-speed video data transmission,
The video data transmission device includes a transmission packet generation unit that divides data in a TS format or a TTS format into a TS packet, a TTS packet, and an FEC packet in order to distribute and transmit to a plurality of paths, and the transmission packet generation unit. Comprising one or a plurality of transmission means for sequentially distributing and transmitting the divided and generated packets to the IP network,
The transmission packet generating means includes a packet dividing means for dividing TS format or TTS format data received from the encoding means via a single or two ports into TS packets or TTS packets and FEC packets; Alignment number assigning means for assigning to the FEC packet the sequence number of the TS packet or TTS packet that has been divided and processed immediately before by the packet dividing means, and the transmission means comprising one or more TS packets or TTS packets and FEC packets A distributed transmission system for video data, characterized by comprising: a transmission packet distribution means that distributes to each other.   The encoding means passes the generated TS packet or TTS packet through one port and the generated FEC packet through another port to deliver video data in TS format or TTS format to the video data transmitting device. The video data distributed transmission system according to claim 1.   The transmission means sequentially selects a path to be used for transmission from a plurality of paths, and sends the TS packet or the TTS packet and the FEC packet generated by the transmission packet generation means to the IP network. The video data distributed transmission system according to claim 1.   The video data receiving apparatus includes: a receiving unit that receives a packet distributed and transmitted by the transmitting unit; an alignment storage unit that aligns the packets received by the receiving unit; and a TS packet that is aligned by the alignment storage unit 2. The video data distributed transmission system according to claim 1, further comprising video data restoration means for integrating the TTS packet and the FEC packet into a viewable format and transmitting the data to the decoding means.   The alignment storing means includes a packet alignment means for aligning the TS packet or TTS packet and FEC packet received by the receiving means in the order of the sequence number of each packet and for each packet type, and the aligned TS packet or TTS packet. First storage means comprising a first buffer area for temporarily storing packets, second storage means comprising second buffer areas for temporarily storing FEC packets, and packets sorted by the packet sorting means for each type of first buffer 5. The video data distributed transmission system according to claim 4, further comprising buffering means for storing in the area or the second buffer area.   The video data restoration means includes restoration data selection means for selecting each of the TS packets or TTS packets and FEC packets temporarily stored in the buffer by the buffering means after selection, and arranged TS packets or TTS. The FEC packet is inserted (arranged) after the TS packet or TTS packet when the sequence number of the packet matches the sequence number of the FEC packet assigned by the sorting number assigning means, and the FEC packet is inserted. 6. The video data distributed transmission system according to claim 5, further comprising packet integration means for deleting the assigned sequence number.   2. The distributed video data transmission system according to claim 1, wherein the video data transmission device includes a transmission schedule adjustment unit that monitors and adjusts packet transmission processing by the transmission unit.   2. The video data distributed transmission system according to claim 1, wherein the video data transmitting apparatus includes a division control unit that monitors and controls packet division processing by the packet division unit. 7. The distributed video data transmission system according to claim 6, wherein the video data receiving apparatus includes an integrated control unit that monitors and controls packet integration processing by the packet integration unit.   2. The distributed video data transmission system according to claim 1, wherein the video data transmission device is provided with a bandwidth securing means for securing a bandwidth for video distribution. Since the video data distributed transmission system transmits and / or receives TS format data or TTS format data to the IP network via SIP,
The video data transmitting device and the video data receiving device are separately provided, receive the video data transmitted by the video data transmitting device and transmit it to the IP network, and the video data transmitted from the IP network A relay device that receives and passes the video data to the video data receiving apparatus includes a session establishment unit that establishes a SIP session in response to a SIP session establishment request, a session management unit that monitors and controls the established session, and an established session Session disconnection means for disconnecting on demand,
The relay device resumes the session establishment request after performing an error response without performing the backward operation when the session establishment unit does not accept the response to the session establishment request, and the session disconnection unit responds to the session disconnection request. 5. The video data distributed transmission system according to claim 1, wherein the session is disconnected without waiting.   12. The video data distributed transmission system according to claim 11, wherein the relay device is provided with a bandwidth securing means for securing a bandwidth for video distribution including a bandwidth of 15 Mbps to 25 Mbps.   The IP network includes an NGN (Next Generation Network), and a path used for transmitting TS format data or TTS format data includes a path secured on the NGN. Item 12. The video data distributed transmission system according to Item 11. 12. The video data distributed transmission system according to claim 11, wherein the video data transmission device performs streaming transmission of video data using RTP under session management by RTCP.

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