JP2001016554A - Video transmission method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize transmission of a plurality of video signals through a single transmission line and flexibility with respect to a change in the number of signals to be sent. SOLUTION: A transmitter side is provided with a control signal generating section 203 that generates a control signal including information denoting the kind and number of video signals multiplexed by a multiplexer section 204 and with a channel control section 205 that controls the number and the kind of signals multiplexed by the multiplexer section 204 depending on the control signal, and a receiver side is provided with a control signal reception section that separates the control signal from the received signal, a separation section that separate the video signal from the received signal and provides an output of the video signal, and a channel control section that controls separation of the video signal and its output conducted by the separation section on the basis of the information of the control signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for transmitting a digital video signal.

[0002]

2. Description of the Related Art In conventional video transmission, a different transmission path is used for each video signal. As a transmission method in this case, for example, the standard “1” formulated by the Japan Radio Industry Association
125/60 HDTV (High Definition)
ION Television signal bit serial interface standard (BTAS-004A). FIG. 6 is an explanatory diagram showing luminance data and color difference data according to this transmission method. In this transmission method, luminance data (Y) and color difference data (Cb / Cr) of one HDTV signal are digital effective lines surrounded by an effective video start timing reference code (SAV) and an effective video end timing reference code (EAV). Housed in the area.

FIG. 6A shows an accommodation form of luminance data (Y), and FIG. 6B shows color difference data (Cb / Cr). In actual transmission, these two signals are multiplexed, converted from parallel to serial, and transmitted through one transmission line. Therefore, in this transmission method, only HDTV is used as a video signal to be transmitted, and the number of transmission signals can correspond to only one. SDTV (Standard
Although there is a similar standard in "Definition Television" signal in "SMPTE standard 259M", a single signal type and the number of corresponding signals are 1 in common.

FIG. 7 is a block diagram showing a configuration of a video transmission apparatus using such a transmission system. In FIG.
701 is a transmitting device, and 702 is a receiving device. The transmitting device 701 includes a plurality of SDTV transmitting devices 703 and a plurality of HDTV transmitting devices 704. However, FIG. 7 shows a case where three SDTV transmission devices 703 and one HDTV transmission device 704 are included. Receiving device 7
02 includes a plurality of SDTV receivers 705 and a plurality of HDTV receivers 706. However, in FIG.
The case where three SDTV receiving apparatuses 705 and one HDTV receiving apparatus 706 are included is shown. The SDTV transmitter 703 and the SDTV receiver 705 are point-to-
The points are connected by SDTV transmission lines. Also, HDT
The V transmitter 704 and the HDTV receiver 706 are also connected via a point-to-point HDTV transmission path.

Next, the operation will be described. First, SDT
The transmission of the V signal will be described. SDTV signal SD (t
1) is processed by the SDTV transmitting apparatus 703 and transmitted to the SDTV receiving apparatus 705 via the SDTV transmission path. The SDTV receiving apparatus 705 is an SDTV transmitting apparatus 703.
To obtain the SDTV signal SD (r1).
The same applies to the SDTV signals SD (r2) and SD (r3).

Next, transmission of an HDTV signal will be described.
The HDTV signal HD (t) is processed by the HDTV transmission device 704 and transmitted to the HDTV reception device 706 via the HDTV transmission path. HDTV receiver 706 is HDT
Performs a process reverse to that of the V transmission device 704 and outputs the HDTV signal HD
(R) is obtained.

[0007]

Since the conventional video transmission method and the conventional video transmission apparatus are configured as described above, transmission paths are required by the number of SDTV signals and HDTV signals to be transmitted. However, there is a problem that it is difficult to flexibly cope with a change in the number of signals.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a plurality of video signals can be transmitted through a single transmission line, and the number of transmitted signals can be changed flexibly. It is an object of the present invention to obtain a compatible video transmission method and apparatus.

[0009]

According to a video transmission method according to the present invention, a control signal including information on a type of a signal to be multiplexed and the number of signals to be multiplexed is generated on a transmitting side, and the control signal and the video signal are generated. Is multiplexed and transmitted to the transmission path, and the receiving side separates the control signal of the signal received from the transmission path, and controls the type and the number of video signals to be separated based on the control signal. It was done.

[0010] The video transmission method according to the present invention provides an HDTV.
, And the HDTV channel information indicating the number of SDTV signals and the SDTV channel information indicating the number of SDTV signals are included in the control signal.

The video transmission method according to the present invention is such that an error correction signal for detecting an error in a control signal is included in the control signal.

[0012] A video transmission apparatus according to the present invention comprises a control signal generating means for generating a control signal including information on the type of video signal to be multiplexed and the number of video signals to be multiplexed, and a multiplexing apparatus for multiplexing video signals. Control means for controlling the type and number of signals to be multiplexed by the multiplexing means in accordance with the control signal, and control for separating the control signal from the received signal Signal receiving means, separating means for separating and outputting the video signal from the received signal, based on information about the type and number of signals included in the control signal separated by the control signal receiving means, And receiving means having channel control means for controlling the separation and output of the video signal performed by the separating means.

[0013] The video transmission apparatus according to the present invention is an HDTV.
HDTV channel information indicating the number of SDTV signals and SDTV channel information indicating the number of SDTV signals are included in the control signal.

According to the video transmission apparatus of the present invention, the control signal includes an error correction signal for detecting an error in the control signal.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a block diagram showing a configuration of a video transmission device to which the video transmission method according to the first embodiment is applied. In the figure, 101 is a transmitting device (transmitting means), 10
Reference numeral 2 denotes a receiving device (receiving means). The transmitting apparatus 101 includes three SDTVs (Standard Definei).
SD (t) which is a signal Television signal.
1), SD (t2), SD (t3) and one HDTV
(High Definition Televisi
on) The signal HD (t) is input. Also,
From the receiving apparatus 102, three SDTV signals SD
(R1), SD (r2), SD (r3) and one HD
HD (r) which is a TV signal is output. Note that the transmission device 101 and the reception device 102 are connected by a transmission path.

FIG. 2 is a block diagram showing the internal configuration of the transmitting apparatus 101. In the figure, 201-1 is an SDTV data processing unit, 207 is an SDTV interface unit, 20
Reference numeral 8 denotes an SDTV speed converter. 201-2 and 20
An SDTV data processing unit 1-3 has the same configuration as the SDTV data processing unit 201-1. 202 is an HDTV data processing unit, 209 is an HDTV interface unit, 210
Is an HDTV speed converter. 203 is a control signal generation unit (control signal generation means), 204 is an SDTV signal, HDT
A multiplexing unit (multiplexing unit) for multiplexing a video signal such as a V signal; 205, a channel control unit (channel control unit);
206 is a transmission interface unit.

FIG. 3 is a block diagram showing the internal configuration of the receiving apparatus 102. In the figure, 301 is a reception interface unit, 302 is a separation unit (separation unit), 303 is a control signal reception unit (control signal reception unit), 304 is a channel control unit (channel control unit), and 305-1 is an SDTV data processing unit It is. Reference numeral 307 denotes an SDTV speed conversion unit, and reference numeral 308 denotes an SDTV interface unit. 305-2, 305
-3 is an S which has the same configuration as the SDTV data processing unit 305-1.
It is a DTV data processing unit. 306 is an HDTV data processing unit, 309 is an HDTV speed conversion unit, 310 is an HDTV data
Interface section.

Next, the operation will be described. The transmitting apparatus 101 in FIG. 1 has three SDTV signals, SD
(T1), SD (t2), SD (t3) and one HDT
HD (t), which is a V signal, is input. The signal format of the SDTV signal is, for example, an SDTV serial digital signal (hereinafter, SD-SDI) compliant with SMPTE standard 259M.
Signal). The signal format of the HDTV signal is, for example, an HDTV serial digital signal (hereinafter, referred to as an HD-SDI signal) conforming to the SMPTE standard 292M. The transmitting apparatus 101 performs processing on the input SDTV signal and HDTV signal.

Referring to the block diagram shown in FIG. 2, the input SDTV signal SD (t1) is
The SD-SDI signal is terminated in the SDTV interface unit 207 in the TV data processing unit 201-1 and converted into a format suitable for processing in the transmission device 101. For example, serial / parallel conversion of a signal is performed. The SDTV speed conversion unit 208 has a function of temporarily storing the received SD-SDI signal, and has a buffer memory for storing the received SD-SDI signal therein. SD
The SD-SDI signal stored in the TV speed conversion unit 208 is read out by the multiplexing unit 204, and the multiplexing unit 20
4, multiplexed with other SDI signals, etc.
It is transmitted as a transmission signal to the transmission path.

SDTV signals SD (t2), SD (t3)
, The same processing as in the SDTV data processing unit 201-1 is performed in the SDTV data processing unit 201-2 and the SDTV data processing unit 201-3. HDT
The V signal HD (t) is transmitted to the HD-SDI interface unit 209 in the HDTV data processing unit 202 by the HD-SDI.
The signal is terminated and converted into a format suitable for processing in the transmission device 101. For example, serial / parallel conversion of a signal is performed.

The HDTV speed converter 210 receives the HD
-Has a function of temporarily storing the SDI signal, and has a buffer memory for storing the received HD-SDI signal therein.

H stored in HDTV speed conversion section 210
The D-SDI signal is read by the multiplexing unit 204,
The multiplexing unit 204 multiplexes the multiplexed signal with another SDI signal and the like, and transmits the multiplexed signal to the transmission path as a transmission signal.

The control signal generator 203 is a channel controller 2
05, and generates a control signal (CTL) included in a transmission signal described later based on the channel information. The multiplexing unit 204 obtains channel information from the channel control unit 205, and based on the channel information, obtains an SD-SDI signal,
The multiplexing process of the HD-SDI signal and the control signal (CTL) is performed.

The channel control unit 205 has information (channel information) such as the type of a signal to be multiplexed, and transmits the channel information to the control signal generation unit 203 and the multiplexing unit 204.
Output to

FIGS. 4A and 4B are explanatory diagrams showing a frame structure of a transmission signal. FIG. 4A shows a case where three SDTV signals are multiplexed, and FIG. 4B shows a case where one HDTV signal is multiplexed. (C) shows a case where one HDTV signal and one SDTV signal are multiplexed. In addition, FIG.
FIG. 4 shows the configuration of a control signal (CTL) included in each of (b) and (c). The control signal (CTL) includes a synchronization signal (SYNC) and HDTV channel information (HD-C
H), SDTV channel information (SD-CH), and an error detection code (CRC). SYNC is a signal for detecting frame synchronization of a transmission signal. HD-CH is HDT
V indicates the number of multiplexes. In this embodiment,
It becomes "0" or "1". SD-CH indicates the number of multiplexed SDTVs, and takes a value from "0" to "3" in this embodiment.

FIG. 5 shows the values of SD-CH and HD-CH in each of the multiplexing examples (a), (b) and (c). CRC
Is used for bit error detection for SYNC, HD-CH, and SD-CH in the CTL.

The signal multiplexed into the transmission frame by the multiplexing unit 204 is transmitted to the transmission interface unit 20.
In 6, processing such as transmission path encoding is performed, and transmitted as a transmission signal to the transmission path.

Next, the operation of the receiving apparatus 102 will be described with reference to FIG. The transmission signal received from the transmission apparatus 101 is subjected to transmission path decoding processing or the like in the reception interface unit 301, and is converted into a signal format suitable for the reception apparatus 102. The signal converted by the receiving interface unit 301 is sent to the separating unit 302 and the control signal receiving unit 303. The control signal receiving unit 303 extracts the HD-CH and the SD-CH from the CTL part of the received transmission frame.
Further, the control signal receiving unit 303 converts the received CTL into CR
C is calculated, and if it does not match the received CRC, it is determined that there is a bit error, and if it matches, it is determined that there is no bit error. The control signal receiving unit 303 transfers the extracted HD-CH, SD-CH and “bit error presence / absence information” to the channel control unit 304.

The channel control section 304 controls the demultiplexing section 302 using the above-mentioned "channel information" and "bit error presence / absence information". The separation unit 302 is a channel control unit 3
When "bit error presence / absence information" from 04 indicates "bit error present", a predetermined signal, for example, a black burst signal is output without using the data of the received transmission signal. When the “bit error presence / absence information” from the channel control unit 304 indicates “no bit error”, the transmission signal is distributed and output based on the “channel information” from the channel control unit 304. For example, if HD-CH is "1" and SD
When -CH is "1", since the data is transmitted in the multiplexing pattern of FIG. 4C, the data of the HD1 part of FIG. 4C is output to the HDTV data processing unit 306, and the data of the SD1 part is output. To the SDTV data processing unit 305-1.

The HDTV data processing unit 306
The V-speed converter 309 temporarily stores the HD1 data in the buffer memory. The stored HD1 data is HD
The signal is read from the HDTV speed conversion unit 309 at a bit rate of −SDI, converted into a signal format of an HD-SDI signal in the HDTV interface unit 310, and output as an HDTV signal.

The SD1 data is transmitted to the SDTV data processing unit 3
In the SDTV speed conversion unit 307 in 05-1, the SD
One data is temporarily stored in the buffer memory. The stored SD1 data is converted to SDT at the SD-SDI bit rate.
The signal is read from the V-speed conversion unit 307, converted into a signal format of an SD-SDI signal in the SDTV interface unit 308, and output as an SDTV signal.

As described above, according to the first embodiment, a plurality of video signals such as an SDTV signal and an HDTV signal can be multiplexed and transmitted by a single transmission line, and it is not necessary to provide a plurality of networks, and There is an effect that a video transmission method and apparatus capable of realizing flexible video transmission with respect to a change in the number of signals can be obtained.

In the embodiment described above, 3
Although one SDTV signal and one HDTV signal are transmitted, the transmission of other combinations can be easily realized by setting the frame length of the transmission frame to another length.

[0034]

As described above, according to the present invention, a control signal including information on the type of signal to be multiplexed and the number of signals to be multiplexed is generated on the transmission side, and the control signal and the video signal are multiplexed. Since the receiving side separates the control signal of the signal received from the transmission line and controls the type and the number of video signals to be separated based on the control signal, In addition, there is an effect that a plurality of video signals can be transmitted through a single transmission line, and that a change in the number of transmitted signals can be flexibly handled.

According to the present invention, HDTV channel information representing the number of HDTV signals and STV representing the number of SDTV signals are provided.
Since the DTV channel information is included in the control signal, a plurality of HDTV signals or SDT
There is an effect that the V signal can be transmitted, and that it is possible to flexibly cope with a change in the number of signals to be transmitted.

According to the present invention, since an error correction signal for detecting an error in a control signal is included in the control signal, a plurality of video signals can be transmitted with high reliability over a single transmission path. In addition, there is an effect that it is possible to flexibly respond to a change in the number of signals to be transmitted.

According to the present invention, control signal generating means for generating a control signal including information on the type of video signal to be multiplexed and the number of video signals to be multiplexed, and multiplexing means for multiplexing the video signal Control means for controlling the type and number of signals to be multiplexed by the multiplexing means in accordance with the control signal, the transmission means comprising: a control signal receiving means for separating the control signal from a received signal; ,
A separating unit that separates and outputs the video signal from the received signal, and the separating unit performs the separation based on information about a type and a number of signals included in the control signal separated by the control signal receiving unit. Since the receiving means is provided with a channel control means for controlling the separation and output of the video signal, a plurality of video signals can be transmitted on a single transmission line, and the number of signals to be transmitted is changed. Also has the effect of being able to respond flexibly.

According to the present invention, HDTV channel information representing the number of HDTV signals and SDTV representing the number of SDTV signals are provided.
Since the control signal includes the TV channel information, a plurality of HDTV signals or SDTs can be transmitted on a single transmission line.
There is an effect that the V signal can be transmitted, and that it is possible to flexibly cope with a change in the number of signals to be transmitted.

According to the present invention, since the control signal includes an error correction signal for detecting an error in the control signal, a plurality of video signals can be transmitted with high reliability over a single transmission line, and There is an effect that it is possible to flexibly cope with a change in the number of signals to be transmitted.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a video transmission device to which a video transmission method according to a first embodiment of the present invention is applied.

FIG. 2 is a block diagram illustrating an internal configuration of a transmission device of the video transmission device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing an internal configuration of a receiving device of the video transmission device according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram illustrating a frame configuration of a transmission signal in the video transmission device according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of multiplexing in the video transmission device according to the first embodiment of the present invention.
FIG. 4 is an explanatory diagram showing values of the.

FIG. 6 is an explanatory diagram showing luminance data and chrominance data according to a conventional transmission method performed using a different transmission path for each video signal.

FIG. 7 is a block diagram illustrating a configuration of a conventional video transmission device.

[Explanation of symbols]

101 transmitting apparatus (transmitting means), 102 receiving apparatus (receiving means), 203 control signal generating section (control signal generating means), 204 multiplexing section (multiplexing means), 205, 30
4 Channel control unit (channel control unit), 302 separation unit (separation unit), 303 control signal reception unit (control signal reception unit).

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C063 AA01 AA11 AB03 AB07 AB11 CA23 CA40 DA07 5K014 AA01 BA05 EA07 FA11 HA00 HA10 5K022 AA03 AA12 AA22 5K028 AA11 DD01 DD02 EE03 KK03 LL02 MM09 PP12 SS06 SS16

Claims (6)

[Claims] 1. A transmitting side generates a control signal including information on a type of a signal to be multiplexed and the number of signals to be multiplexed, multiplexes the control signal and a video signal, transmits the multiplexed signal to a transmission path, and In the video transmission method, the control signal of the signal received from the transmission path is separated, and the type and the number of video signals to be separated are controlled based on the control signal. 2. The control signal includes HDTV channel information indicating the number of HDTV signals and SD signal indicating the number of SDTV signals.
2. The method according to claim 1, wherein the information includes TV channel information.
The described video transmission method. 3. The video transmission method according to claim 1, wherein the control signal includes an error correction signal for detecting an error in the control signal. 4. A control signal generating means for generating a control signal including information on a type of a video signal to be multiplexed and the number of video signals to be multiplexed, a multiplexing means for multiplexing the video signal, and the multiplexing Transmitting means having channel control means for controlling the type and number of signals to be multiplexed by the means in accordance with the control signal; control signal receiving means for separating the control signal from a received signal; Separating means for separating and outputting the video signal from the separated signal, and the image performed by the separating means based on information on the type and number of signals included in the control signal separated by the control signal receiving means. A receiving means having a channel control means for controlling signal separation and output; 5. The control signal generated by the control signal generation means includes: HDTV channel information indicating the number of HDTV signals;
5. The video transmission apparatus according to claim 4, wherein SDTV channel information indicating the number of SDTV signals is included. 6. The control signal generated by the control signal generation means includes an error correction signal for detecting an error in the control signal.
The video transmission device according to the above.