JP5370565B2 - Video signal communication system and communication method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video signal communication method for preventing network congestions and transmitting a video signal with minimized quality deterioration even in the case where transmission band is not secured, when transmitting an uncompressed HDTV signal using an IP network. <P>SOLUTION: Transmission includes converting an uncompressed video signal in sampling rate on the basis of band control information received from a network; carrying out control of a transmission band with the number of data being reduced; IP-packetizing a video signal obtained after the transmission band control; and transmitting the signal to a receiving side via the network from a transmission control section. Reception includes: receiving the video signal obtained after the transmission band control; subjecting the signal to reverse conversion of sampling rate based on the band control information; reconstructing it to a transmission band of an original video signal to form the original video signal. If transmission requests of a video signal occur from a plurality of lines at the same time, then the transmission band is controlled based on a priority for each video signal and band conversion information produced from band control information from the receiving side. A plurality of IP packets are selectively multiplexed and sent out to the network. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a video signal communication system and a communication method therefor, and in particular, an IP (Internet Protocol) protocol communication network such as the Internet for video signals such as uncompressed high-definition television (HDTV). TECHNICAL FIELD The present invention relates to a communication system and a communication method for transmission using the Internet.

  In general, services for transmitting video signals such as HDTV using an IP network such as the Internet have been put into practical use, and various methods have been proposed. In a communication network such as the Internet where QoS (Quality of Service) is not guaranteed, the transmission band and transmission quality are not maintained constant. For this reason, when a continuous signal such as a video signal or an audio signal is transmitted in real time, the quality is often deteriorated and high quality transmission is often impossible.

  For example, the methods disclosed in Patent Document 1 and Patent Document 2 control congestion on the network by feeding back information on the transmission band of the network to the transmission side sequentially and controlling the band of the transmitted signal. Therefore, the transmission signal is efficiently transmitted while suppressing the deterioration of quality.

The BTA S-001B, S-002B, S-004B, S-005S, S-006S, and 1125/60 standard HDTV studio system standards listed as Non-Patent Document 1 are like standard uncompressed HDTV signals. An example in which the data amount is fixed is disclosed. The device disclosed in Non-Patent Document 2 transmits an HDTV uncompressed signal using an IP network.
JP 2002-135783 A JP 2003-244695 A BTA S-001B, S-002B, S-004B, S-005S, S-006S, 1125/60 standard HDTV studio system standard Takeaki Mochida et al. “Uncompressed HDTV Video Multiplexing Technology in 10 Gigabit Networks” NTT Technology Journal 2005.2, pp. 46-49

  However, in the methods disclosed in Patent Document 1 and Patent Document 2, a signal to be transmitted is originally a signal whose transmission rate can be controlled on the premise of a signal encoded by the MPEG (Moving Picture Experts Group) method or the like. This is a method of controlling so as to keep the quality as high as possible. Therefore, this method cannot be applied when the amount of data is fixed as in the uncompressed signal of HDTV standardized in Non-Patent Document 1.

  Furthermore, the device disclosed in Non-Patent Document 2 transmits HDTV uncompressed signals using an IP network, but the network uses a high-speed line such as 10 Giga Ethernet and is sufficient. It is assumed that it will be used within a guaranteed guaranteed transmission band. For this reason, there is no particular indication for dealing with network traffic congestion.

  Recently, a network with a guaranteed bandwidth called QoS has been introduced in signal transmission using an IP network. This classifies according to the destination of the signal to be transmitted and the service type, and performs priority control and bandwidth control for each class. Usually, priority is given to signals that require real-time characteristics, such as video signals and audio signals. For other data that does not require real-time properties, a best-effort transmission method is often used.

  However, in the case of a high-speed signal such as an uncompressed HDTV signal, this transmission band requires 1.5 Gbit / s or more per channel. For example, when trying to run multiple HDTV uncompressed signals in the 2.4 Gbit / s transmission band, or when trying to send multiple video signals in the 10 Gbit / s transmission band, the transmission band will be 10 Gbit / s. In such a case, the network becomes congested. As a countermeasure against this congestion, it is difficult to guarantee the bandwidth by classifying QoS for the same type of video signal. In addition, it is difficult to control the transmission rate like the MPEG compression signal.

  In view of such a problem, the present invention prevents network congestion and minimizes quality deterioration of video signals even when a transmission band is not secured for a request for simultaneously transmitting video signals of a plurality of lines. An object of the present invention is to provide a video signal communication system and a communication method thereof.

  In order to solve the above-described problems, the present invention provides a video signal communication system including a video signal transmission device that multiplexes a plurality of video signals and transmits the multiplexed video signals through a communication network, and a video signal reception device that receives the video signals. The video signal transmitting device has designation information for designating whether or not to band-convert the signal regardless of the priority order, and each of the plurality of original video signals set with the priority order is designated as the first luminance signal and the first luminance signal. Conversion means for each original video signal for converting into a color difference signal, and band conversion information for preferentially controlling the band conversion from the designation information and the band control information and the priority order for each of the plurality of original video signals. Based on the conversion information, the transmission band of the first luminance signal and the first color difference signal is controlled, and the original video signal for generating the second luminance signal and the second color difference signal whose transmission band is controlled, respectively. Separate transmission band control means, packetizing means for each original video signal for assembling the second luminance signal and the second color difference signal into a packet to which band conversion information is assigned for each of a plurality of original video signals, and band conversion information Based on the bandwidth control signal, the selective multiplexing means for selecting and multiplexing the packets that can be transmitted based on the packet and generating multiplexed packet data and the bandwidth control signal from the video signal receiving device are received. And a transmission control means for generating multiplexed information and transmitting the multiplexed packet data to the video signal receiving device via the network. The video signal receiving device receives the multiplexed packet data sent via the network. In addition, a reception control method for generating a band control signal from the line status of the network and transmitting the band control signal to the video signal transmitting apparatus. And a multiplexed packet separating means for separating the packet from the received multiplexed packet data and restoring the band conversion information, and extracting video data for each separated packet, and extracting the video data to the second luminance Video data extraction and conversion means for each packet that is converted into a signal and a second color difference signal and output, and the transmission band of the second luminance signal and the second color difference signal for each packet based on the restored band conversion information A transmission band restoration unit for each packet that restores the transmission band of the first luminance signal and the first color difference signal, and the original video signal is restored from the restored first luminance signal and the first color difference signal for each packet. And a video signal restoration means for each packet.

  In order to solve the above-mentioned problem, the present invention provides a communication method in a video signal communication system in which a plurality of original video signals are converted into video signal data, multiplexed, and transmitted through a communication network. In the video signal transmission device on the transmission side, prior to the transmission of the multiplexed video signal data, the usable transmission band of the communication network is acquired as the band control information and set for each of the plurality of original video signals. The first step of acquiring priority information and specifying information specifying whether or not to perform band conversion of the signal regardless of the priority order, and the acquired specification information for each original video signal, as well as the bandwidth control information and priority Band conversion information for priority control of the band is generated based on the order, and the transmission band of the original video signal is converted based on the band conversion information to change the transmission band. A second step of adaptively selecting whether to generate the converted video signal data or discarding the original video signal, and adding the band conversion information to the video signal data after the band conversion Then, these are generated as packets, the generated packets are selected based on the band conversion information, multiplexed, and a third step of generating multiplexed packet data, and the generated multiplexed packet data The fourth step of transmitting to the video signal receiving device on the receiving side in this system via the communication network, and receiving the multiplexed packet data in this video signal receiving device, generating the received video signal data, The fifth step of generating control information and transmitting it to the video signal transmitting device, and separating the received video signal data into packets, restoring the band conversion information, And a sixth step of inversely converting the transmission band of the received video signal data to the transmission band of the original video signal based on the band conversion information and restoring the original video signal from the inversely converted signal data. And

  According to the present invention, even when the transmission band is not secured when receiving a request to transmit video signals of a plurality of lines simultaneously, selective multiplexing prevents network congestion and reduces video signal quality. It can be transmitted with a minimum. The present invention is particularly advantageously applied to a video communication system such as television broadcast program material transmission and video distribution in which an uncompressed video signal is transmitted using an IP network.

It is a block diagram which shows the schematic structure of the video signal transmitter in the Example of the video signal communication system which concerns on this invention. It is a block diagram which shows schematic structure of the video signal receiver in the Example of the video signal communication system which concerns on this invention. It is a figure which shows the example of 1 structure of the luminance signal sampling rate conversion part in the video signal transmission apparatus of FIG. FIG. 2 is a diagram illustrating a configuration example of a color difference signal sampling rate conversion unit in the video signal transmission apparatus of FIG. 1. It is a figure explaining the calculation example of the sampling rate conversion in the video signal transmitter of FIG. FIG. 2 is a filter characteristic diagram illustrating an example of a low-pass filter characteristic in the video signal transmission device of FIG. 1. It is a figure explaining IP packetization of the video data by the video signal transmitter shown in FIG. It is a figure explaining IP packetization of video data in relation to FIG. It is a figure which shows the structural example of the sender report which the video signal transmission apparatus of FIG. 1 produces. It is a figure which shows the structural example of the recipient report which the video signal receiver of FIG. 2 produces. It is a block diagram which shows schematic structure of the video signal transmitter in the other Example of the video signal communication system which concerns on this invention. FIG. 12 is a block diagram showing a schematic configuration of a video signal receiving device corresponding to the transmitting device of FIG. FIG. 12 is a diagram illustrating an example of priority control and a multiplexing method of the video signal transmission device illustrated in FIG. 11, and illustrates a case where 6 signals are full-band multiplexed and 2 signals are discarded. FIG. 12 is a diagram illustrating an example of priority control and a multiplexing method of the video signal transmission device illustrated in FIG. 11, and illustrates a case where four signals are full-band multiplexed and four signals are multiplexed in a band 1/2. FIG. 12 is a diagram illustrating an example of priority control and a multiplexing method of the video signal transmission device illustrated in FIG. 11 and illustrating a case where 8 signals are multiplexed in a band 3/4. FIG. 12 is a diagram illustrating an example of priority control and a multiplexing method of the video signal transmission device illustrated in FIG. 11 and illustrating a case where 8 signals are multiplexed in a band 3/4.

  Embodiments of a video signal communication system according to the present invention will now be described in detail with reference to the accompanying drawings. First, referring to FIG. 11 and FIG. 12, these are block diagrams showing the configuration of an embodiment of the video signal communication system according to the present invention. FIG. 11 shows the transmission side in the video signal communication system 70, that is, the video signal transmission device. FIG. 12 shows the receiving side, that is, the video signal receiving device 88. Both devices 78 and 88 are connected to an IP (Internet Protocol) protocol communication network 56 such as the Internet.

  In the video signal communication system 70 of the embodiment, the video signal transmission device 78 has designation information for designating whether or not the SDI-INF S / P conversion unit 71 performs band conversion of the signal regardless of the priority order, and has priority. Each of the 8 HD SDI signals in which the order is set is converted into a luminance signal and a color difference signal as an output signal 301, and the sampling rate conversion processing unit 72 assigns designation information, band control information, and priority for each of the 8 HD SDI signals. Band conversion information 306 for preferential control of band conversion is generated from this, and the transmission band of the luminance signal and the color difference signal is controlled based on the band conversion information 306. A color difference signal is generated and output as an output signal 302. The IP packetizing unit 73 assembles another luminance signal and other color difference signal into a packet to which band conversion information is assigned for each of the eight HD SDI signals. Output signal 303, selective multiplexing unit 74 selects and multiplexes packets that can be transmitted based on band conversion information 306, generates multiplexed packet data 304, and transmission control unit 77 generates a video signal. The bandwidth control signal 311 is received from the reception device 88, the bandwidth control information 305 is generated based on the bandwidth control signal 311, and the multiplexed packet data is transmitted to the video signal reception device 88 via the network 56.

  The video signal receiving device 88 receives the multiplexed packet data 310 sent via the network 56 by the reception control unit 81, generates a band control signal 311 from the line status of the network 56, and performs this band control. The signal 311 is sent to the video signal transmitter 78, and the packet is separated from the multiplexed packet data 401 received by the multiplexed packet separator 82, and the band conversion information 405 is restored and separated by the video data extraction converter 83. For each packet, video data is extracted, the video data is converted into other luminance signals and other color difference signals, and output as an output signal 403, and restored by the sampling rate inverse conversion processing unit 84 for each packet. Based on the band conversion information 405, the transmission band of the other luminance signal and other color difference signal is restored to the transmission band of the luminance signal and color difference signal, and the output signal 404 is output, and the SDI-INF S / P For each packet section 85, to restore the original image signal 407 from the restored luminance signal and the color difference signals.

  As a result, even when the transmission bandwidth is not ensured when a request for simultaneous transmission of video signals 300 of multiple lines is received, network congestion is prevented by selective multiplexing, and video signal quality degradation is minimized. For example, the present invention is particularly advantageously applied to a video communication system such as television broadcast program material transmission and video distribution in which an uncompressed video signal is transmitted using an IP network.

  First, referring to FIG. 1, a video signal 100 is input to the video signal transmission device 52 in this embodiment. The video signal 100 may be, for example, a 1.485 / 1.001 Gbit / s HD-SDI (High Definition-Serial Digital Interface) signal standardized in Non-Patent Document 1. The HD-SDI signal 100 is input to the SDI INF-S / P conversion unit 61. The SDI INF-S / P conversion unit 61 interfaces (INF) with the HD-SDI signal 100 and serial / parallel (S / P) converts the signal into a luminance (Y) signal 101, a color difference (PbPr) signal 102, and Video signal conversion means for outputting the synchronization timing signal 103 is configured. The luminance (Y) signal 101 is connected to the luminance signal sampling rate conversion unit 62 and the luminance signal delay adjustment unit 66. The color difference (PbPr) signal 102 is connected to the color difference signal sampling rate conversion unit 63 and the color difference signal delay adjustment unit 67. The synchronization timing signal 103 is connected to the timing extraction unit 64.

  The timing extraction unit 64 is connected to the SDI INF-S / P conversion unit 61, the luminance signal sampling rate conversion unit 62, and the chrominance signal sampling rate conversion unit 63, and the synchronization timing generated by the SDI INF-S / P conversion unit 61 This is a functional unit that generates a timing signal necessary for sampling rate conversion from the signal 103.

  The video signal transmission device 52 includes a sampling rate control unit 65, which is connected to the transmission control unit 10, the luminance signal sampling rate conversion unit 62, and the chrominance signal sampling rate conversion unit 63. This is a control circuit that generates sampling rate control information 105 and 106 based on the band control information 104 and controls the luminance signal sampling rate conversion unit 62 and the chrominance signal sampling rate conversion unit 63.

  The luminance signal sampling rate conversion unit 62 is connected to the SDI INF-S / P conversion unit 61, the selection unit 68, the timing extraction unit 64, and the sampling rate control unit 65. The luminance signal sampling rate conversion unit 62 receives the luminance signal 101 from the SDI INF-S / P conversion unit 61, takes a timing with the output signal 107 of the timing extraction unit 64, and receives the sampling rate control information from the sampling rate control unit 65 The luminance signal 101 is converted into a sampling rate by 105 and sent to the selection unit 68. Similarly, the chrominance signal sampling rate conversion unit 63 receives the chrominance signal 102 from the SDI INF-S / P conversion unit 61, takes a timing with the output signal 108 of the timing extraction unit 64, and samples from the sampling rate control unit 65. This is a functional unit that converts the sampling rate of the color difference signal 102 based on the rate control information 106 and sends it to the selection unit 68.

  The luminance signal delay adjustment unit 66 is connected to the selection unit 68, and adjusts the delay time so that there is no data shift in the luminance signal when the luminance signal output 110 of the sampling rate conversion unit 62 is adaptively switched. It is. Similarly, the color difference signal delay adjustment unit 67 is connected to the selection unit 68 and adjusts the delay time so that there is no data shift in the color difference signal when the color difference signal output of the sampling rate conversion unit 63 is adaptively switched. It is a functional part.

  The selection unit 68 outputs a luminance signal 112 and a color difference signal 114, and these signals are supplied to the IP packetization unit 69. Based on the band control information 104 from the transmission control unit 10, the selection unit 69 selectively switches the output signal 110 from the luminance signal sampling rate conversion unit 62 from a signal obtained by converting a sampling rate, which will be described later, to a signal that is not converted. The resultant signal is output to the output 112, and the output signal 111 from the chrominance signal sampling rate conversion unit 63 has a selection function of selectively switching a signal that has not been converted from the sampling rate and a signal that has not been converted. These timing extraction unit 64, sampling rate control unit 65, luminance signal sampling rate conversion unit 62, chrominance signal sampling rate conversion unit 63, luminance signal delay adjustment unit 66, chrominance signal delay adjustment unit 67, and selection unit 68 have transmission band control Means.

  The IP packetization unit 69 is an IP packetization function unit that assembles the outputs 112 and 114 from the selection unit 68 into IP packets. The output 115 is connected to the transmission control unit 10. The transmission control unit 10 is supplied with band control information 104 as a control signal to the sampling rate control unit 65, the selection unit 68, and the IP packetizing unit 69, and further connected to the video signal receiving device 54 on the receiving side via the network 56 Has been. The transmission control unit 10 transmits and receives a protocol for establishing a communication link with the reception control unit 11 on the reception side, and transmits a video signal 202 that has been converted into an IP packet to the video signal reception device 54 on the reception side. It is.

  Next, the video signal receiving device 54 will be described with reference to FIG. The video signal receiving device 54 includes a reception control unit 11, and the reception control unit 11 is connected to the network 56 and the video data extraction / conversion unit 12. The reception control unit 11 is connected to the network 56 and transmits / receives a protocol to establish a communication link with the transmission control unit 10 of the video signal transmission device 52 on the transmission side, and receives the video signal 202 converted into an IP packet. This is a functional unit that sends the data to the video data extraction / conversion unit 12. The reception control unit 11 also performs various communication controls such as transmission / reception of an RTCP packet, which will be described later, and has a function of transmitting the bandwidth control information 200 to the video signal transmission device 52 on the transmission side using the RTCP packet, for example.

  The video data extraction / conversion unit 12 includes a luminance signal sampling rate reverse conversion unit 13, a color difference signal sampling rate reverse conversion unit 14, a luminance signal delay adjustment unit 17, a color difference signal delay adjustment unit 18, a timing extraction unit 15, and a sampling rate control unit 16. And a function unit that is connected to the selection unit 19 and extracts video data from the received IP packet to generate a luminance (Y) signal 201, a color difference (PbPr) signal 202, a synchronization timing signal 203, and a band control signal 205. .

  The luminance (Y) signal 201 output from the video data extraction / conversion unit 12 is connected to the luminance signal sampling rate inverse conversion unit 13 and the luminance signal delay adjustment unit 17. Further, the color difference (PbPr) signal 202 is connected to the color difference signal sampling rate inverse conversion unit 14 and the color difference signal delay adjustment unit 18. Further, the synchronization timing signal 203 and the band control signal 205 are connected to the timing extraction unit 15 and the sampling rate control unit 16, respectively.

  The timing extraction unit 15 is connected to the luminance signal sampling rate reverse conversion unit 13 and the chrominance signal sampling rate reverse conversion unit 14, and the timing required for the reverse sampling rate conversion from the synchronization timing signal 203 generated by the video data extraction conversion unit 12 It has the function of generating signals 206 and 207. The sampling rate control unit 16 is connected to the luminance signal sampling rate reverse conversion unit 13 and the chrominance signal sampling rate reverse conversion unit 14, and based on the band control information 205 from the video data extraction conversion unit 12, the sampling rate control information 208 and 209 Are respectively functional units that control the luminance signal sampling rate inverse conversion unit 13 and the color difference signal sampling rate inverse conversion unit 14.

  The luminance signal sampling rate inverse conversion unit 13 is connected to the timing extraction unit 15, the sampling rate control unit 16, and the selection unit 19, and uses the luminance (Y) signal 201 from the video data extraction conversion unit 12 as the timing from the timing extraction unit 15. It has an inverse conversion function for performing an inverse conversion of the sampling rate by the signal 206 and the sampling rate control information 208 from the sampling rate control unit 16.

  Similarly, the color difference signal sampling rate inverse conversion unit 14 is connected to the timing extraction unit 15, the sampling rate control unit 16, and the selection unit 19, and the color difference (PbPr) signal 202 from the video data extraction conversion unit 12 is used as the timing extraction unit 15. And the sampling rate control information 209 from the sampling rate control unit 16 and the function of performing reverse sampling rate conversion.

  The luminance signal delay adjustment unit 17 is a functional unit that is connected to the selection unit 19 and adjusts the delay time so that there is no data shift when the luminance signal output 210 of the sampling rate inverse conversion unit 13 is adaptively switched. . Similarly, the color difference signal delay adjustment unit 18 is connected to the selection unit 19 and adjusts the delay time so that there is no data shift when the color difference signal output 211 of the sampling rate inverse conversion unit 14 is adaptively switched.

  The selection unit 19 is connected to the SDI INF-P / S conversion unit 20, and based on the band control information 205 from the video data extraction conversion unit 12, the output 210 of the luminance signal sampling rate inverse conversion unit 13 and the color difference signal sampling rate conversion A selection function for switching the output 211 of the unit 14 to the output of the luminance signal delay adjustment unit 17 and the output of the color difference signal delay adjustment unit 18 and sending the resulting signal 212 to the SDI INF-P / S conversion unit 20 Have. These luminance signal sampling rate reverse conversion unit 13, color difference signal sampling rate reverse conversion unit 14, timing extraction unit 15, sampling rate control unit 16, luminance signal delay adjustment unit 17, color difference signal delay adjustment unit 18 and selection unit 19 are transmitted. Band decoding means is configured.

  The SDI INF-P / S conversion unit 20 converts the output 212 of the selection unit 19 from parallel to serial and outputs the HD-SDI signal 213, which is the original video signal, and parallel serial (P / S) A video signal restoration means having a conversion function is configured.

  In the operating state, the system 50 uses the video signal transmission device 52 on the transmission side to convert the uncompressed video signal 100 based on the bandwidth control information 200 received from the network 56 side to reduce the number of data. The transmission band is controlled and sent to the video signal receiving device 54 on the receiving side. The video signal receiving device 54 on the receiving side receives the video signal 202 after the transmission band control, reversely converts the sampling rate based on the band control information, restores to the transmission band of the original video signal, Restore to video signal.

  More specifically, in the video signal transmission device 52, the HD-SDI video signal 100 arrives at 1.485 / 1.001 Gbit / s. When the HD-SDI signal 100 is input to the SDI INF-S / P converter 61, the SDI INF-S / P converter 61 converts the HD-SDI signal 100 from the serial format to the parallel format, and further, the luminance ( Y) A signal 101, a color difference (PbPr) signal 102, and a synchronization timing signal 103 are output.

  The luminance (Y) signal 101 is input to the luminance signal sampling rate conversion unit 62. The luminance signal sampling rate conversion unit 62 takes the timing by the output signal 107 of the timing extraction unit 64, that is, in synchronization with this, performs the sampling rate conversion by the sampling rate control information 105 from the sampling rate control unit 65, and the result The signal 110 is sent to the selection unit 68. Similarly, the chrominance (PbPr) signal 102 is input to the chrominance signal sampling rate conversion unit 63, and the chrominance signal sampling rate conversion unit 63 takes a timing from the output signal 108 of the timing extraction unit 64, The sampling rate is converted according to the sampling rate control information 106, and the resulting signal 111 is sent to the selection unit 68.

  The luminance signal sampling rate conversion unit 62 and the chrominance signal sampling rate conversion unit 63 are configured by filters for converting at the sampling rate. In this embodiment, the band of the HD-SDI signal 100 that is the input signal is 3/4 and 1 Has a bandwidth compression function to / 2. FIG. 3 shows a configuration example of the luminance signal sampling rate conversion unit 62, and FIG. 4 shows a configuration example of the color difference signal sampling rate conversion unit 63. In this embodiment, the number of samples is converted only in the effective video area of the input video signal 100, that is, the signal area excluding the vertical blanking part and the horizontal blanking part, and 1920 samples per line. This signal of the effective video area is referred to as an effective video signal.

  In this embodiment, the sampling rate conversion is performed as follows. As shown in FIG. 3 and FIG. 4, the luminance signal sampling rate conversion unit 62 and the chrominance signal sampling rate conversion unit 63 are both composed of a finite impulse response (FIR) filter, and 1920 samples are converted into 1440 or 960. Convert to sample. In both figures, the symbol “D” indicates the one-sample delay element 33 or 37. In the present embodiment, a filter using 10 samples is formed. For example, the luminance (Y) signal 101 is formed by 10 stages of delay elements 33. Also, for the color difference (PbPr) signal 102, the number of samples is half that of the luminance (Y) signal 101, but the blue color difference (Pb) signal and the red color difference (Pr) signal are multiplexed so that the luminance (Y ) The number of 1920 samples is the same as signal 101. In this filter configuration, the Pb signal and the Pr signal are delayed by two samples so as not to mix with each other. The FIFO units 34 and 38 shown in both figures are first-in first-out registers.

FIG. 5 shows a specific calculation example in the sampling rate conversion. When 1920 samples are converted to 1440 samples, the conversion is 4: 3. Therefore, for example, the output can be obtained by sequentially switching the three types of filter coefficients b4, b5, and b6 in the figure as shown in the following calculation formula.
b4 = k12 x a1 + k9 x a2 + k6 x a3 + k3 x a4 + k0 x a5 + k3 x a6 + k6 x a7 + k9 x a8 + k12 x a9
b5 = k13 x a2 + k10 x a3 + k7 x a4 + k4 x a5 + k1 x a6 + k2 x a7 + k5 x a8 + k8 x a9 + k11 x a10 + k14 x a11
b6 = k14 x a3 + k11 x a4 + k8 x a5 + k5 x a6 + k2 x a7 + k1 x a8 + k4 x a9 + k7 x a10 + k10 x a11 + k13 x a12
The filter coefficients of this calculation formula are controlled by coefficient control units 31 and 35 shown in FIGS. 3 and 4, respectively. The FIFO write control unit 32 in the luminance signal sampling rate conversion unit 62 controls the timing signal 39 to sequentially switch the output of the FIFO unit 34 like the sampling coefficients b4, b5, and b6. Thereby, the input luminance signal 101 of the luminance signal sampling rate conversion unit 62 is converted from 1920 samples to 1440 samples. In addition, the FIFO write control unit 36 in the color difference signal sampling rate conversion unit 63 controls the timing signal 40 and sequentially switches the output of the FIFO unit 38 like the sampling coefficients b4, b5, and b6. Thus, the input color difference signal 102 of the sampling rate conversion unit 63 is converted from 1920 samples to 1440 samples.

Similarly, when converting from 1920 samples to 960 samples, an output can be obtained by sequentially switching filter coefficients as shown in the following calculation formula C3, for example.
c3 = k'12 x a1 + k'9 x a2 + k'6 x a3 + k'3 x a4 + k'0 x a5 + k'3 x a6 + k'6 x a7 + k'9 x a8 + k'12 x a9
FIG. 6 illustrates the frequency characteristics of the filters 62 and 63 having this filter coefficient. When 1920 samples are converted to 1440 samples for the input signal 100 having the frequency band f, since this conversion is in a 4: 3 relationship, if the input signal 100 is virtually oversampled three times, The signal 100A of FIG. 4 is 3/4 band compression of the original signal 100, that is, 1/4 band compression for the oversampled signal. That is, this filter has the characteristics of a low-pass filter. When 1920 samples are converted to 960 samples, the conversion is 2: 1. Therefore, the output characteristic 100B can be obtained by applying the above calculation formula c3 to each sample.

  Similarly, FIG. 6 shows the frequency characteristics of this filter. Here, as in the case of conversion from 1920 samples to 1440 samples with an output characteristic of 100A, the filter coefficient is oversampled by a factor of 3 and then half the bandwidth of the original signal (with respect to the oversampled signal) Indicates the coefficient for the data that has the low-pass filter characteristics. For the filter characteristic 100B, it is also possible to calculate a filter characteristic of a half band without oversampling.

  Returning to FIG. 1, the outputs of the luminance signal sampling rate conversion unit 62 and the color difference signal sampling rate conversion unit 63 are input to the selection unit 68. Luminance signal delay adjustment unit 66 and chrominance signal delay adjustment unit 67 adjust the delay times of input signals 101 and 102, respectively, so that there is no data shift when adaptively switching the output of sampling rate conversion units 62 and 63 To do. Outputs of the luminance signal delay adjustment unit 66 and the color difference signal delay adjustment unit 67 are input to the selection unit 68. Outputs of the luminance signal delay adjustment unit 66 and the color difference signal delay adjustment unit 67 are signals that are not subjected to sampling rate conversion, and are obtained by adjusting the delay times of the input signals 101 and 102, respectively.

  The selection unit 68 selectively switches whether the input signals 110 and 111 are subjected to sampling rate conversion or not. The signals 112 and 114 after the switching are input to the IP packetizing unit 69. The IP packetizing unit 69 assembles an input signal into an IP packet, that is, packetizes it. 7, 8, and 9 explain the video data 112 and 114 output from the IP packetizing unit 69 and its IP packetization.

  In this embodiment, the format and method for converting an HDTV signal into an IP packet is the RFC 3550 (RTP: A Transport) of RFC (Request For Comments) issued by the IETF (The Internet Engineering Task Force) that establishes technical standards related to the Internet. Protocol for Real-Time Applications), RFC3497 (RTP Payload Format for Society of Motion Picture and Television Engineers (SMPTE) 292M Video) and Pro-MPEG Code of Practice # 4 release 1 (Transmission of High Bit Rate Studio Streams over IP Networks) may be used.

  More specifically, the video data is transmitted on the payload of the RTP packet. However, since the data basically needs to be processed in units of bytes, a luminance (Y) signal per sample is shown in FIG. The color difference (PbPr) signal is converted into 10-bit signals, that is, a total of 20-bit signals into 8-bit units. Thus, as shown in FIG. 8, 280 samples of data in the EAV (End of Active Video), SAV (Start of Active Video), and ANC (ANCyillary data) DATA areas are represented by 8 bits * 700. The data for 1920 samples of the effective video signal is divided into four 480 samples, and the data of each 480 samples is represented by 8 bits * 1200.

  In addition, since it is assumed that the RTP packet is transmitted by Ethernet (trademark), the packet length needs to be within a MAC (Media Access Control) frame. Normally, since the user data of the MAC frame is determined to be within 1500 bytes, the data per packet is limited to 1200 bytes in consideration of the header part of the IP packet and the RTP packet. As shown in FIG. 8, 700 bytes of EAV, SAV and ANC DATA are transmitted as one independent packet. When sampling rate conversion is not performed for video data, four 1200 bytes of data are transmitted in four packets to form one line of data. When the sampling rate is converted to 3/4, three 1200 bytes of data are transmitted in 3 packets, and when the sampling rate is converted to 1/2, two 1200 bytes of data are transmitted in 2 packets, respectively. To do. In other words, video data is a maximum of 1200 bytes, and 1 packet per line of data is transmitted in 3 to 5 packets.

  Returning to FIG. 1, the IP packetized signal 115 is sent to the network 56 via the transmission control unit 10. The transmission control unit 10 also receives a band control signal 200 for controlling the sampling rate from the video signal receiving device 54 on the receiving side via the network 56. This bandwidth control is performed using a packet defined by RTCP (RTP Control Protocol) so as to include the sender report SR of FIG. 9 and the receiver report RR of FIG. This is realized by exchanging with 54.

  This is a method stipulated in RFC3550. In the video signal receiving device 54 on the receiving side, the discard rate and the number of discarded packets are calculated from the received packets, and the sender side RR is exemplified as the receiver report RR illustrated in FIG. Send to 52. On the transmission side 52, an appropriate sampling rate is selected based on the discard rate in the received report RR, and the luminance signal sampling rate conversion unit 62, the color difference signal sampling rate conversion unit 63, and the selection unit 68 are controlled. Therefore, the unit for switching the sampling rate coincides with the RTCP packet transmission / reception cycle.

  Incidentally, in the video signal receiving device 54, the reception control unit 11 is connected to the network 56 and performs various communication controls such as transmission / reception of RTCP packets. For example, the bandwidth control information 200 is transmitted to the transmission side 52 using an RTCP packet. The video data extraction / conversion unit 12 extracts video data from the received IP packet, and converts the byte unit signal into a luminance (Y) signal 202 and a color difference (PbPr) signal 203, each as a 10-bit signal.

  The luminance (Y) signal 202 and the color difference (PbPr) signal 203 output from the video data extraction / conversion unit 12 are input to the luminance signal sampling rate inverse conversion unit 13 and the color difference signal sampling rate inverse conversion unit 14, respectively. The luminance signal delay adjustment unit 17 and the color difference signal delay adjustment unit 18 are also input. The luminance signal sampling rate reverse conversion unit 13 and the chrominance signal sampling rate reverse conversion unit 14 perform conversion opposite to the sampling rate conversion on the transmission side based on the band control information, and return the number of samples to that of the original input. . This basic configuration is realized by the same configuration and method as the sampling rate conversion shown in FIGS. The sampling rate conversion process is a generally known technique including an application for down-converting an HDTV signal into an SDTV (Standard Definition Television) signal, and thus description of the calculation method and filter characteristics is omitted.

  The luminance signal delay adjusting unit 17 and the chrominance signal delay adjusting unit 18 are connected to the output 210 of the luminance signal sampling rate inverse conversion unit 13 and the output 211 of the chrominance signal sampling rate inverse conversion unit 14 with respect to a full-rate signal of 1920 samples. Delay adjustment for matching timing is performed. The selection unit 19 performs selection according to the sampling number of the received signal. The SDI INF-P / S conversion unit 20 converts the output 212 of the selection unit 19 from a parallel format to a serial format, and restores and outputs the HD-SDI signal 213.

  As described above, according to the present embodiment, when a high-speed continuous signal such as an uncompressed HDTV signal is transmitted using a network such as the Internet where QoS is not guaranteed, the sampling rate of the video signal to be transmitted is set. Conversion is performed according to the transmission band of the network, thereby controlling the transmission band. As a result, it is possible to perform efficient video transmission in which congestion does not occur on the network and deterioration in quality is suppressed. Further, when performing bandwidth control, by reducing the number of samples, it is possible to prevent fatal errors such as continuous data interruption and data corruption due to network congestion.

  Furthermore, the data amount reduction processing by sampling rate conversion is much shorter than when high-efficiency encoding such as MPEG is performed, the processing itself is simple, and an uncompressed signal that does not change the sampling rate. Can be easily realized. In particular, it is suitable for applications such as material transmission used in television broadcasting.

  Next, another embodiment of the present invention will be described. A video signal communication system 70 according to another embodiment is shown as a block diagram in FIG. 11 and FIG. FIG. 11 shows the transmitting side, that is, the video signal transmitting device 78 in the video signal communication system 70, and FIG. 12 shows the receiving side, that is, the video signal receiving device 88. Both devices 78 and 88 are connected to an IP protocol communication network 56 such as the Internet.

  In the video signal communication system 70 of the present embodiment, the video signal transmission device 78 on the transmission side has the same band conversion requirement indicating whether or not to perform band conversion on all signals regardless of priority as a system value. Has a non-designated value. In this embodiment, the priority is set for each of the eight video signals 300. Therefore, for each video signal, band conversion information 306 is generated from the same band conversion necessity designation value and the band control information 311 received from the network 56 side and the priority order, and an uncompressed video signal is generated based on the band conversion information 306. The sampling rate is converted for 300, the transmission band is controlled to reduce the number of data, and the resulting signal 302 is converted into an IP packet. Further, a plurality of IP packets are selected and multiplexed, and this multiplexed signal 310 is sent to the video signal receiving apparatus on the receiving side. When receiving the multiplexed signal 310, the video signal receiving device 54 on the receiving side separates each IP packet, performs reverse conversion of the sampling rate based on the band conversion information for each IP packet, and returns to the transmission band of the original video signal. Restore the original video signal.

  First, the video signal transmission device 78 will be described with reference to FIG. The video signal transmission device 78 includes an SDI INF-S / P conversion unit 71, a sampling rate conversion processing unit 72, an IP packetization unit 73, a selection multiplexing unit 74, a wired control unit 75, a sampling rate control unit 76, and a transmission control unit. Includes 77. In particular, the SDI INF-S / P conversion unit 71, the sampling rate conversion processing unit 72, and the IP packetizing unit 73 are provided with numbers corresponding to the number of input video signals. In this embodiment, eight video signals 300 (HD-SDI signal 1 to signal 8) are input to the video signal transmission device 78. The video signal 300 may be a 1.485 / 1.001 Gbit / s HD-SDI (High Definition-Serial Digital Interface) signal standardized in Non-Patent Document 1, for example. The priority order of the HD-SDI signal 300 is set for each signal and is input to each SDI INF-S / P conversion unit 71. The SDI INF-S / P conversion unit 71 has the same function as the SDI INF-S / P conversion unit 61 (FIG. 1) in the previous embodiment. In other words, the SDI INF-S / P conversion unit 71 interfaces with the HD-SDI signal 300, captures it, separates the captured HD-SDI signal 300 into three types of signals, and converts each of the separated signals to serial-parallel conversion. Then, the obtained luminance (Y) signal 101, color difference (PbPr) signal 102, and synchronization timing signal 103 are output. These output signals 101, 102 and 103 correspond to the output signal 301 of the SDI INF-S / P conversion unit 71.

  The SDI INF-S / P converter 71 supplies the S / P converted output signal 301 to the sampling rate conversion processor 72. Although not shown, the sampling rate conversion processing unit 72 is the luminance signal sampling rate conversion unit 62 and the luminance signal delay adjustment unit 66, the color difference signal sampling rate conversion unit 63 and the color difference signal delay adjustment unit 67, and the timing extraction unit in the previous embodiment. 64, which has the same configuration and function as the selection unit 68. Each sampling rate conversion processing unit 72 is supplied with the respective sampling rate control information 307 from the sampling rate control unit 76, and is subjected to sampling control according to the supplied sampling rate control information.

  Here, the sampling rate control unit 76 has a function of generating the sampling rate control information 307 from the band conversion information 306. The sampling rate control unit 76 receives the band conversion information 306 from the priority control unit 75, generates the sampling rate control information 307 from the band conversion information 306, and thereby controls the sampling rate conversion processing unit 72.

  The sampling rate conversion processing unit 72 supplies the selected output signal 302 to the IP packetizing unit 73. The IP packetizing unit 73 has substantially the same function as the IP packetizing unit 69 in the previous embodiment, and is an IP packetizing function unit that assembles the output 302 of the sampling rate conversion processing unit 72 into an IP packet. However, when assembling an IP packet, the bandwidth conversion information 306 is also added to the IP packet, which is different from the IP packetization unit 69 of the previous embodiment.

  Incidentally, the output 302 of the sampling rate conversion processing unit 72 corresponds to the outputs 112 and 114 from the selection unit 68 in the video signal transmitting apparatus 50 in the previous embodiment. The IP packetizing unit 73 outputs the output signal 303 converted into the IP packet to the selective multiplexing unit 74. The selective multiplexing unit 74 selects and multiplexes a plurality of IP packets 303 based on the band conversion information 306 supplied from the priority control unit 75, and generates a multiplexed IP packet 304. The selective multiplexing unit 74 supplies the multiplexed IP packet 304 to the transmission control unit 77.

  The transmission control unit 77 is connected to the priority control unit 75 and further connected to the reception side 88 via the network 56. The transmission control unit 77 has the same function as the transmission control unit 10 in the previous embodiment, and performs transmission and reception of packets according to the protocol for establishing a communication link with the reception control unit 81 of the device 88 on the reception side, This is a control function unit that transmits the video signal 310 that has been converted into the multi-IP packet to the device 88 on the receiving side.

  The priority control unit 75 is connected to the transmission control unit 77, the sampling rate control unit 76, the IP packetizing unit 73, and the selective multiplexing unit 74. The priority control unit 75 generates the band conversion information 306 based on the same band conversion necessity designation value, the band control information received from the transmission control unit 77, and the priority set for each input video signal, The generated band conversion information 306 is sent to the sampling rate control unit 76, the IP packetizing unit 73, and the selective multiplexing unit 74.

  Next, priority control will be described in more detail with reference to FIGS. 11 to 13D. The priority control unit 75 acquires the same band conversion necessity designation value that is a system setting value, acquires the band control information from the transmission control unit 77, and acquires the priority order set for each video signal. In this embodiment, the video line 300 is 8 lines (signal 1 to signal 8). The bandwidth control information 311 is composed of information on the bandwidth A that can be transmitted on the network line, and the bandwidth A is 10 Gbit / s as shown in FIGS. 13A to 13D. The video signal bandwidth of each video line is equivalent to 1.6 Gbit / s.

  In the case of the example shown in FIGS. 13A to 13D, since the signals 1 to 8 are simultaneously input to the video signal transmission device 78 and each signal has a speed of 1.6 Gbit / s, the necessary transmission band B is 1.6 * 8 = 12.8 Gbit / s. However, since the band A that can be transmitted through the network line is 10 Gbit / s as described above, the band B exceeds the band A and cannot transmit all of the signals 1 to 8. For this reason, based on the priority order set for each of the video signals 1 to 8, the band conversion and discarding of the signals 1 to 8 are performed.

  In one example, the priority is configured from four levels: low to “Discardable”, “1/2 Bandwidth”, “3/4 Bandwidth”, and “1/1 Bandwidth = Full Bandwidth”. Has been. In addition, the video signal transmission device 78 has a “same band conversion necessity designation value” which is a setting value of “whether all signals are band-converted equally regardless of priority” as a system value. ing. When the same band conversion necessity specification value is “No”, the band conversion information 306 is generated as follows.

  When the four priority levels are a, b, c, and d, and the total number of signal lines before band conversion is 8, band conversion information 306 is generated under the following three conditions.

a + b + c + d = 8 ... Condition (1)
B = 1.6 * (0 * a + (1/2) * b + (3/4) * c (1/1) * d) <10 (= A) ... Condition (2)
Bandwidth conversion is applied from the lowest priority, but the priority level of a, b, c, d is changed so that it is closest to band A, and the optimal priority level and a, b, c, d are changed. Calculate ... Condition (3)
In the case shown in FIG. 13A, if a = 2, b = 1, c = 1, and d = 4, that is, signal 7 and signal 8 correspond to a, signal 6 corresponds to b, and signal 5 corresponds to c. If the signals 1 to 4 correspond to d, the lowest priority level a = 2 is applied first. That is, the signals 7 and 8 corresponding to a are discarded. At this time,
B = 1.6 * ((1/2) * 1 + (3/4) * 1 + (1/1) * 4) = 8.4 <10
The condition (2) is satisfied, but in order to satisfy the condition (3), the level of b is changed from 1/2 band to 1/1 band, and the level of c is changed to 3/4 band in the same way. Change from normalization to 1/1 bandwidth.

This
B = 1.6 * ((1/1) * 1 + (1/1) * 1 + (1/1) * 4) = 9.6 <10
Thus, the conditions (2) and (3) are also satisfied. Therefore, a = 2 and d = 6, the signals 7 and 8 are discarded, the signals 1 to 6 are 1/1 bands, and the information for each signal becomes the band conversion information 306.

Next, in the case shown in FIG. 13B, when signal 4 to signal 8 are set to 1/2 band and signal 1 to signal 3 are set to 1/1 band, a = 0, b = 5, c = 0 D = 3. At this time, the condition (2) is
B = 1.6 * ((0) * 0 + (1/2) * 5 + (3/4) * 0 + (1/1) * 3) = 8.8 <10
Thus, the condition (2) is satisfied, but in order to satisfy the condition (3), b = 5 is changed to b = 4, and d = 3 is changed to d = 4. At this time
B = 1.6 * ((0) * 0 + (1/2) * 4 + (3/4) * 0 + (1/1) * 4) = 9.6 <10
Thus, the conditions (2) and (3) are also satisfied. Therefore, b = 4, d = 4, signal 5 to signal 8 is 1/2 band, signal 4 is 1/1 band, and as a result, signal 1 to signal 4 is 1/1 band. This information becomes the band conversion information 306.

Next, in the case shown in FIG. 13C, when signal 3 to signal 8 are set to 3/4 band and signal 1 to signal 2 are set to 1/1 band, a = 0, b = 0, c = 6 , D = 2. At this time, the condition (2) is
B = 1.6 * ((0) * 0 + (1/2) * 0 + (3/4) * 6 + (1/1) * 2) = 10.4> 10
Since the condition (2) is not satisfied, c = 6 is changed to c = 8 and d = 2 is changed to d = 0 to satisfy the conditions (2) and (3). At this time
B = 1.6 * ((0) * 0 + (1/2) * 0 + (3/4) * 8 + (1/1) * 0) = 9.6 <10
Thus, the conditions (2) and (3) are also satisfied. Therefore, c = 8 and d = 0, and the signals 1 to 8 have a 3/4 band, and the information for each signal becomes the band conversion information 306.

Next, when the same band conversion necessity designation value is “necessary”, band conversion information 306 is generated as follows. In this case, the band conversion condition is
B = 1.6 * P * 8 <10 (= A) ・ ・ ・ ・ Condition (4)
P must be the maximum of the specified bandwidth values ... Condition (5)
It is.

  An example of this case is shown in FIG. 13D. P is a predetermined bandwidth value, and in this embodiment, it is one of 1/2 bandwidth, 3/4 bandwidth, or 1/1 bandwidth, but satisfies the conditions (4) and (5). Is P = 3/4 bandwidth, and at this time, B = 1.6 * (3/4) * 8 = 9.6 <10. That is, the signals 1 to 8 have a 3/4 band, and this information becomes the band conversion information 306.

  In these band conversion information 306, in the case shown in FIG. 13A, six signals among signals 1 to 8 are selected and multiplexed in the full band, that is, without band conversion, and the two signals are discarded. In the case shown in FIG. 13B, four of the signals 1 to 8 are multiplexed in the full band, that is, without band conversion, and the four signals are band-converted to ½ and multiplexed. In the case shown in FIG. 13C, all signals 1 to 8 are band-converted to 3/4 and multiplexed. Also in the case shown in FIG. 13D, all signals 1 to 8 are band-converted to 3/4 and multiplexed.

  As described above, when the same band conversion necessity designation value is “No”, the priority control unit 75 performs band conversion or discard of each video signal based on the band control information and the priority order of each signal. Are applied in ascending order of priority, and a band conversion value for maximally using the transmittable band A is generated as band conversion information 306 for each video signal. When the same band conversion necessity designation value is “necessary”, an optimal uniform band conversion value is generated as band conversion information 306 for each video signal.

  Next, the video signal receiving device 88 will be described with reference to FIG. The video signal receiving device 88 includes a reception control unit 81, which is connected to the network 56 and the multiplexed packet separation unit 82. The reception control unit 81 has the same function as the reception control unit 11 in the previous embodiment, is connected to the network 56, transmits and receives a protocol for establishing a communication link with the transmission control unit 77 of the transmission side 78, This is a functional unit that receives the video signal 310 that has been converted into the multiplexed IP packet and sends it to the multiplexed packet separation unit 82. Similarly to the reception control unit 11 in the previous embodiment, the reception control unit 81 performs various communication controls such as transmission / reception of RTCP packets, and transmits, for example, band control information 311 to the transmission side 77 using the RTCP packets. It has a function.

  The multiplexed packet separation unit 82 is connected to the reception control unit 81, the eight video data extraction / conversion units 83, and the sampling rate control unit 86. The multiplexed packet separation unit 82 separates the output signal 401 formed of the multiplexed IP packetized video signal 310 received from the reception control unit 81 into individual IP packets, and sends them to the respective video data extraction / conversion units 83. Also, the band conversion information 306 in the IP packet is restored and sent to the sampling rate control unit 86 as an output signal 405.

  The sampling rate control unit 86 receives the output signal 405 composed of the band conversion information 306, generates a sampling rate control signal 406 from the band conversion information 306, and controls the sampling rate thereby to control the sampling rate inverse conversion processing unit 84. To control.

  The video data extraction / conversion unit 83 has substantially the same function as the video data extraction / conversion unit 12 in the previous embodiment, and extracts video data from the received IP packet to obtain a luminance (Y) signal 201, a color difference (PbPr) This is a functional unit that generates the signal 202 and the synchronization timing signal 203. In the previous embodiment, the band control signal 205 is configured to be generated by the video data extraction / conversion unit 12, but this function is different from that of the video data extraction / conversion unit 83 in this embodiment. The output 403 of each video data extraction / conversion unit 83 is sent to each sampling rate inverse conversion processing unit 84.

  The sampling rate inverse conversion processing unit 84 is connected to the video data extraction / conversion unit 83, the sampling rate control unit 86, and the SDI INF-P / S conversion unit 85. The sampling rate reverse conversion processing unit 84 is the luminance signal sampling rate reverse conversion unit 13, the chrominance signal sampling rate reverse conversion unit 14, the luminance signal delay adjustment unit 17, the chrominance signal delay adjustment unit 18, and the timing extraction unit 15 in the previous embodiment. Also, it has the same configuration and function as the selection unit 19, and restores the transmission band of the luminance signal and color difference signal to the transmission band of the video signal.

  The output 404 of each sampling rate inverse conversion processing unit 84 is sent to each SDI INF-P / S conversion unit 85. The SDI INF-P / S converter 85 is the same as in the previous embodiment, and converts the output 404 from parallel to serial and outputs the HD-SDI signal 407, which is the original video signal, and parallel serial. (P / S) Has a conversion function.

  In the operating state, the system 70 is the transmission side video signal transmission device 78, the band control information 311 received from the network 56 side, and the band conversion information 306 generated from the priority set for each video signal 300. Based on the above, sampling rate conversion is performed on a plurality of uncompressed video signals 300, the number of data is reduced, the transmission band is controlled, and these are multiplexed and sent to the receiving side.

  When the video signal receiving device 88 on the receiving side receives the multiplexed video signal 310 after the transmission band control, the multiplexed video signal 310 is separated into individual video signals, and each individual video signal has a bandwidth. The sampling rate is inversely converted based on the conversion information to restore the transmission band of the original video signal, and further restore the original video signal.

  More specifically, in the video signal transmission device 78, a plurality of HD-SDI video signals 300 arrive at 1.485 / 1.001 Gbit / s. When the HD-SDI signal 300 is input to the SDI INF-S / P converter 71, the SDI INF-S / P converter 71 converts the HD-SDI signal 300 from the serial format in the same manner as in the previous embodiment. The signal is converted into a parallel format and an output signal 301 is output. The output signal 301 corresponds to the luminance (Y) signal 101, the color difference (PbPr) signal 102, and the synchronization timing signal 103 in the previous embodiment. The output signal 301 is sent to the sampling rate conversion processing unit 72.

  When the sampling rate conversion processing unit 72 receives the sampling control information 307 from the sampling control unit 76, the sampling rate conversion processing unit 72 converts each output signal 301 to the sampling rate based on the sampling control information 307. This sampling rate conversion method may be the same as in the previous embodiment. The sampling rate-converted signal 302 is sent to the IP packetizing unit 73 and converted into an IP packet. The IP packetization method may be almost the same as in the previous embodiment, except that the band conversion information 306 is further added to the IP packet. The band conversion information 306 is received from the priority control unit 75.

  The IP packetized signal 303 that has been converted into an IP packet is then sent to the selective multiplexing unit 74. Based on the band conversion information 306 received from the priority control unit 75, the selection multiplexing unit 74 selects an IP packetized signal 303 that is not in the discard mode from among a plurality of IP packetized signals 303, and multiplexes the multiplexed signals by multiplexing them. An IP packet signal 304 is generated and sent to the transmission control unit 77. The transmission control unit 77 sends the multiplexed IP packet signal 304 to the network 56 as a transmission signal 310.

  The transmission control unit 77 also receives the band control information 311 from the reception side via the network 56 and sends it to the priority control unit 75. The priority control unit 75 acquires the same band conversion necessity specification value that is a system setting value, acquires the band control information 311 from the transmission control unit 77 as an output 305, and sets the priority set for each video signal. get.

  In the present embodiment, as described above, with the eight video lines 300 (signal 1 to signal 8), the bandwidth A that can be transmitted on the network line is 10 Gbit / s, and the necessary transmission band B is 12.8 Gbit / s. s. Therefore, based on the same band conversion necessity designation value and the priority order set for the video signals 1 to 8, the conversion and discarding of the bands of the signals 1 to 8 are performed.

  For example, when the same band conversion necessity designation value is “No”, in the case shown in FIG. 13A, six signals among signals 1 to 8 are selected and multiplexed in the full band, that is, without band conversion, 13B, four of the signals 1 to 8 are multiplexed in the full band, that is, without band conversion, and the four signals are band-converted to ½ and multiplexed. In the case shown in Fig. 13C, all signals 1 to 8 are band-converted into 3/4 and multiplexed, and as shown in Fig. 13D, when the same band conversion necessity designation value is "necessary" , Signal 1 to signal 8 are all band-converted to 3/4 and multiplexed.

  As described above, when the same band conversion necessity designation value is “No”, the priority control unit 75 performs band conversion or discard of each video signal based on the band control information and the priority order of each signal. Are applied in ascending order of priority, and a band conversion value for maximally using the transmittable band A is generated as band conversion information 306 for each video signal. When the same band conversion necessity designation value is “necessary”, an optimal uniform band conversion value is generated as band conversion information 306 for each video signal. The generated band conversion information 306 is sent to the sampling control unit 76, the IP packetizing unit 73, and the selective multiplexing unit 74.

  In view of this, in the video signal receiving device 88, the reception control unit 81 receives the transmission signal 310 from the video signal transmitting device 78 on the transmission side via the network 56. The reception controller 81 operates in the same manner as in the previous embodiment, and sends the multiplexed IP packet signal 304, which is the received signal 310, to the multiplexed packet separator 82 as an output 401.

  The multiplexed packet separation unit 82 separates the multiplexed IP packet signal 304 into individual IP packet signals 402 and restores the band conversion information 405 for each IP packet. This band conversion information 405 is the same as the band conversion information 306. Each IP packet signal 402 is sent to each video data extraction / conversion unit 83, and each band conversion information 405 is sent to the sampling control unit 76.

  The sampling control unit 76 receives the band conversion information 405 for each IP packet signal 402, generates sampling control information 406, and sends it to the respective sampling rate inverse conversion processing units 84.

  The video data extraction / conversion unit 83 operates in substantially the same manner as in the previous embodiment, extracts video data from the received IP packet, and outputs a luminance (Y) signal 201, a color difference (PbPr) signal 202, and a synchronization timing signal 203. Generated as output signal 403. Band control signal 205 is not generated. Also, the sampling rate inverse conversion processing unit 84 is the luminance signal sampling rate inverse conversion unit 13, the chrominance signal sampling rate inverse conversion unit 14, the luminance signal delay adjustment unit 17, the chrominance signal delay adjustment unit 18, the timing extraction in the previous embodiment. It operates in the same manner as the unit 15 and the selection unit 19, and outputs the output signal 404 as an output signal 404 by inversely converting the output signal 403.

  The output signal 404 of each sampling rate inverse conversion processing unit 84 is sent to each SDI INF-P / S conversion unit 85. Each SDI INF-P / S converter 85 operates in the same manner as in the previous embodiment, converts the output signal 404 from parallel to serial, and outputs the HD-SDI signal 407, which is the original video signal, respectively. .

  As described above, according to the present embodiment, when a high-speed continuous signal such as a plurality of uncompressed HDTV signals is simultaneously transmitted using a network such as the Internet where QoS is not guaranteed, each video to be transmitted is transmitted. The sampling rate of the signal is converted according to the transmission band of the network, thereby controlling the transmission band and selectively multiplexing these video signals for transmission. As a result, efficient video transmission can be performed with respect to a plurality of video signals with no congestion on the network and with suppressed quality degradation. Further, when performing bandwidth control, by reducing the number of samples, it is possible to prevent fatal errors such as continuous data interruption and data corruption due to network congestion.

  Although the above-described embodiments deal with uncompressed HDTV signals, the present invention can be realized with the same configuration and method for SDTV signals. In addition, as an example of sampling rate conversion, the cases of 3/4 and 1/2 have been described. However, the present invention can of course be applied to other conversion ratios.

  In the above-described embodiment, the sampling rate conversion is adaptively switched according to the transmission band. However, for example, the sampling rate conversion can be fixedly switched to a low sampling rate.

  In the above-described embodiment, the transmission side and the reception side are separate devices. Of course, one device has the transmission side function and the reception side function, and can be applied to an example of bidirectional video communication. is there.

  Furthermore, although the above-described embodiment has been applied to an IP network, the present invention is not necessarily limited to an IP network, and is not limited to an existing dedicated line, an asynchronous transfer mode (ATM) line, or a wired network. The present invention is advantageously applied as a method for reducing the transmission band, not limited to a wireless line.

10, 77 Transmission control unit
11, 81 Reception controller
12, 83 Video data extraction and conversion unit
13 Luminance signal sampling rate inverse converter
14 Color difference signal sampling rate inverse converter
15, 64 Timing extractor
16, 65, 76 Sampling rate controller
17, 66, 86 Luminance signal delay adjuster
18, 67 Color difference signal delay adjuster
19, 68 Selection part
20, 71 SDI INF-P / S converter
50, 70 Video signal communication system
52, 78 Video signal transmitter
54, 88 Video signal receiver
61, 85 SDI INF-S / P converter
62 Luminance signal sampling rate converter
63 Color difference signal sampling rate converter
69, 73 IP packetizer
72 Sampling rate conversion processor
74 Selective multiplexing unit
75 Priority control section
82 Multiplexed packet separator
84 Sampling rate inverse conversion processor

Claims (8)

In a video signal communication system including a video signal transmitting device that multiplexes a plurality of video signals and transmits the multiplexed video signals through a communication network, and a video signal receiving device that receives the video signals,
The video signal transmitting device has designation information for designating whether or not to perform band conversion of a signal regardless of priority,
A conversion means for each original video signal for converting each of the plurality of original video signals set with the priority order into the first luminance signal and the first color difference signal,
For each of the plurality of original video signals, band conversion information for performing priority control of band conversion is generated from the designation information, band control information, and the priority order, and the first luminance signal and the first luminance signal are generated based on the band conversion information. A transmission band control unit for each original video signal that controls the transmission band of the color difference signal of 1, and generates the second luminance signal and the second color difference signal, each of which is controlled in transmission band;
For each of the plurality of original video signals, a packetizing unit for each original video signal that assembles a second luminance signal and a second color difference signal into a packet provided with the band conversion information;
Selective multiplexing means for selecting and multiplexing transmittable packets among the packets based on the band conversion information, and generating multiplexed packet data;
A bandwidth control signal is received from the video signal receiving device, the bandwidth control information is generated based on the bandwidth control signal, and the multiplexed packet data is transmitted to the video signal receiving device via the network. Transmission control means,
The video signal receiving device is:
Receiving control means for receiving multiplexed packet data sent via the network, generating the band control signal from the network status of the network, and sending the band control signal to the video signal transmitting device; ,
A multiplexed packet separating means for separating the packet from the received multiplexed packet data and restoring the band conversion information;
For each of the separated packets, video data is extracted, and the video data is converted into a second luminance signal and a second color difference signal for output, and packet-specific video data extraction / conversion means;
For each packet, based on the restored band conversion information, transmission for each packet restores the transmission band of the second luminance signal and the second color difference signal to the transmission band of the first luminance signal and the first color difference signal. Bandwidth restoration means,
A video signal communication system comprising: a packet-specific video signal restoration unit that restores the original video signal from the restored first luminance signal and the first color difference signal for each packet.   The system according to claim 1, wherein when the designation information indicates that band conversion is unnecessary for each original video signal, the band conversion information indicates a usable transmission band of the communication network obtained from the band control information. In order from the signal with the lowest priority, the information is adaptively allocated to the transmission band of the first video signal composed of the first luminance signal and the first chrominance signal, and the designation information needs to be subjected to band conversion. In the case of showing, the transmission bandwidth that can be used for the communication network obtained from the bandwidth control information is generated as information that is allocated as a uniform bandwidth to all the first video signals, and when sampling rate conversion is performed, the sampling rate information is The video signal communication system includes discard information when discarding without performing sampling rate conversion. . The system according to claim 1 or 2,
The transmission band control means for each original video signal controls the sampling rate of the first luminance signal and the first color difference signal for each of the original video signals based on the band conversion information, and the first luminance signal and the first luminance signal Sampling rate conversion of the chrominance signal of 1 and thereby generating a second luminance signal and a second chrominance signal by changing the number of samples of the effective video signal in the original video signal, or the first luminance signal and the first chrominance signal The transmission band of the video signal is controlled by discarding the color difference signal of 2,
The per-packet transmission band restoring means reverses the sampling rate by controlling the sampling rate of the second luminance signal and the second color difference signal of the received video signal data based on the band conversion information for each packet. Thereby, the number of samples of the effective video signal is restored to the number of samples of the original video signal, thereby restoring the transmission band of the first luminance signal and the first color difference signal of the original video signal. Video signal communication system.   4. The system according to claim 1 or 3, wherein the original video signal converting means converts an effective video signal of the original video signal into a first luminance signal and a first color difference signal for each original video signal. A video signal communication system. In a communication method in a video signal communication system in which a plurality of original video signals are converted into video signal data, multiplexed and transmitted through a communication network, the method includes:
In the video signal transmitting device on the video signal data transmitting side, prior to sending the multiplexed video signal data, a usable transmission band of the communication network is acquired as band control information, and a plurality of original video signals A first step of acquiring priority information set for each and acquiring designation information specifying whether or not to perform band conversion of the signal regardless of priority;
For each original video signal, band conversion information for preferentially controlling a band based on the acquired designation information, band control information and priority order is generated, and a transmission band of the original video signal is determined based on the band conversion information. A second step of performing band conversion by adaptively selecting whether to convert and generate video signal data after transmission band conversion or discarding the original video signal;
The band conversion information is added to the video signal data after the band conversion, and these are generated as packets, the generated packets are selected based on the band conversion information, multiplexed, and the multiplexed packet data is A third step to generate,
A fourth step of transmitting the generated multiplexed packet data to the video signal receiving device on the receiving side in the system via the communication network;
In the video signal receiving device, a fifth step of receiving the multiplexed packet data, generating received video signal data, and generating the band control information and transmitting it to the video signal transmitting device;
Separating the received video signal data into packets, restoring the band conversion information, and for each packet, reversely converting the transmission band of the received video signal data to the transmission band of the original video signal based on the band conversion information, And a sixth step of restoring the original video signal from the inversely converted signal data.   6. The method according to claim 5, wherein when the designation information indicates that band conversion is not required for each original video signal, the band conversion information indicates a usable transmission band of the communication network obtained from the band control information. The signals are generated as information that is adaptively allocated to the transmission band of the first video signal composed of the first luminance signal and the first color difference signal in order from the signal having the lowest priority, and the designation information indicates that band conversion is required. In this case, the usable transmission band of the communication network obtained from the band control information is generated as information that is uniformly allocated to all the first video signals. A communication method characterized by including discard information when discarding without performing sampling rate conversion. The method according to claim 5 or 6, wherein
The second step is to perform sampling conversion of the original video signal by controlling the sampling rate of the original video signal based on the band conversion information, thereby changing the number of samples of the effective video signal in the original video signal By converting the transmission band of the video signal,
The sixth step controls the sampling rate of the received video signal data based on the band conversion information, and reverses the sampling of the received video signal data, thereby converting the number of samples of the effective video signal into the original video signal A communication method characterized by restoring to the transmission band of the original video signal by restoring to the number of samples.   8. The method according to claim 5, wherein the video signal transmission device controls a transmission band of the original video signal based on the band conversion information for an effective video signal of the original video signal. Communication method.

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