JPH06284387A - Video signal information transmission system - Google Patents

Abstract

PURPOSE:To effectively utilize the idle transmission data of a synchronizing signal part in an encoded video signal, regarding a system transmitting video signal information. CONSTITUTION:In a video signal transmitter where an A/D conversion means 1 converting video signals including synchronizing signals into digital data, and a synchronizing detection means 2 generating a synchronizing flag for a synchronizing signal period are provided, a transmitter multiplexing video data and a synchronized flag and transmitting it, a D/A conversion means 3 converting reception video data into an analog signal and a synchronizing generation means 4 generating an analog synchronizing signal for a sychronizing flag reception period are provided, and a receiver adding the synchronizing signal to the video signal and reproducing an original signal is provided, information data is converted into the same speed as a video, the data is multiplexed to the video for a synchronizing signal period and transmitted by providing a speed conversion means 5 on the transmitter, and the information data separated for the synchronizing flag reception period is converted into original speed and original data is reproduced by providing a speed conversion means 6 on the receiver.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for transmitting video signal information, and more particularly to an HDTV system utilizing an optical fiber or the like.
The present invention relates to a video signal information transmission system for realizing point-to-point digital transmission of broadband video information such as signals.

For example, in the case of an HDTV signal, the band of the luminance signal (Y) is 30 MHz and the color difference signals (P _b, P _r )
The band is 15 MHz. When performing digital transmission of such signals, since these signals are multiplexed and transmitted, an expensive broadband transmission line is required.

Therefore, even in the effective use of the transmission line,
There is a demand for further expansion of the information capacity that can be transmitted as compared with the transmission capacity (transmission bit rate). In addition, it is indispensable to transmit video and audio at the same time in response to future multi-media, but for that purpose, it is necessary to multiplex both video and audio signals, especially expansion of multiple channels as much as possible. desired. Furthermore, as the reliability of transmission equipment is required more and more, it is important to establish an on-line test method that can be executed simultaneously with information transmission.

[0004]

2. Description of the Related Art A video signal is composed of a luminance signal (Y) and two kinds of color difference signals ( _{Pb, Pr} ) or three kinds of color signals (G, B, R). Therefore, in order to perform digital transmission of video signals, it is necessary to individually encode these signals and then multiplex and transmit them.
Hereinafter, a video signal for HDTV, Y, P _b, as an example of each signal P _r, the conventional encoding and digital transmission methods will be described.

FIG. 6 shows a conventional video signal information transmission system. 11 is analog / digital (A /
D) A converter for converting an analog video signal into video data composed of a digital signal. Reference numeral 12 denotes a synchronization detection circuit, which detects a synchronization signal from video data and creates a synchronization flag. A multiplexing circuit 13 multiplexes the video data and the synchronization flag. A frame generation circuit 14 creates a video frame from digital video data. A transmission circuit 15 transmits framed video data. These constitute a transmitter, and the transmission signal is transmitted to the receiver via a transmission path.

In the receiving device, reference numeral 21 is a receiving circuit, which receives video data from a transmission line. Reference numeral 22 is a frame synchronization circuit, which establishes frame synchronization with the received signal. A separation circuit 23 separates the sync flag and the digital video data from the frame data. A flag detection circuit 24 detects a synchronization flag. 25
Is a digital / analog (D / A) converter, which converts digital video data into an analog video signal in synchronization with a sync flag. Reference numeral 26 is a sync generation circuit, which creates an analog sync signal from the sync flag.
An adder circuit 27 adds the analog video signal and the analog sync signal to reproduce the original video signal.

FIG. 7 illustrates the coding of a video signal. Indicates an analog Y signal, and indicates an analog P _b signal and an analog P _r signal, and a video signal and a sync signal are transmitted alternately. In order to transmit this digitally, the sample data shown in is created and transmitted by encoding into a PCM signal of 8 bits or 10 bits by the sampling clock shown in. Here, F is a sync flag, "1" indicates the value of the sync signal portion, and "0" indicates the value of the video signal portion. D is video data.

As described above, the synchronizing signal portion having the known waveform pattern is transmitted as a 1-bit flag, and the receiving device uses the method of reproducing the same synchronizing signal as the transmitting device when receiving the synchronizing flag. .

Further, conventionally, a method has been adopted in which a transmission channel for an audio signal is set separately from a channel for a video signal and multiplexed for transmission. Further, at the time of a transmission line test of a transmission device, a method of stopping transmission of a video signal and switching to a test signal to execute the test is adopted.

[0010]

In the conventional video signal information transmission system, the sample data of the sync signal is transmitted as it is (or set to a certain fixed value). Since the reproduction of the synchronizing signal in the receiving device is performed by using the synchronizing flag as described above, the sample data in the synchronizing signal is a useless signal, and in the receiving device,
Not being used effectively.

Further, in order to transmit the audio signal, it is necessary to set a channel different from that of the video signal, and at the time of the test, the transmission of the video signal must be stopped in order to transmit the test signal. did not become.

The present invention is intended to solve such a problem of the prior art, and in the video signal information transmission system, effectively uses the unnecessary transmission data of the sync signal portion in the encoded video signal. The purpose is to. Further, in the video signal information transmission method, it is not necessary to set a channel for transmitting an audio signal separately from the channel for the video signal, and it is another object of the present invention to prevent the transmission of the video signal from being stopped at the time of a transmission line test. .

[0013]

[Means for Solving the Problems] (1) FIG. 1 shows a principle configuration of the present invention. The present invention includes an A / D conversion means 1 for converting an analog video signal including an analog sync signal into digital video data, and a sync detection means 2 for detecting a transmission period of the sync signal and generating a sync flag.
A transmitter for multiplexing and transmitting digital video data and a synchronization flag, a D / A conversion means 3 for converting the received digital video data into an analog video signal, and an analog synchronization signal corresponding to the reception period of the synchronization flag. In the video signal transmission device including the synchronization generation means 4 for reproducing the video signal by adding the analog sync signal to the analog video signal, the information data is transmitted to the transmission device in the same manner as the video data. Speed conversion means 5 for converting to speed
And a speed converting means for converting the received information data separated from the received signal into the original speed to the receiving device by multiplexing the information data with the video data in the synchronizing signal transmitting period and transmitting the multiplexed information data. 6 is provided to reproduce the information data.

(2) According to the present invention, in (1), the transmitting device is provided with an A / D converting means 7 for converting an analog audio signal into digital audio data and inputting it to the speed converting means 5 to provide a synchronization signal. During the transmission period, the audio data is multiplexed with the video data and transmitted, and the reception audio data separated from the reception signal during the synchronization flag reception period and converted into the original speed by the speed conversion means 6 is transmitted to the receiving device as an analog audio signal. A D / A conversion means 8 for converting into a voice signal is provided to reproduce an audio signal.

(3) According to the present invention, in (1), the transmitting device is provided with a pattern generating means 9 for generating a test pattern and inputting it to the speed converting means 5, and this pattern data is transmitted during the synchronizing signal transmitting period. Is multiplexed with video data and transmitted,
In the receiving device, the error detecting means 1 for detecting an error in the received pattern data separated from the received signal in the synchronization flag receiving period and converted into the original speed in the speed converting means 6.
0 is provided to test the transmission line on line.

[0016]

2A and 2B are views for explaining the operation of the present invention, in which indicates a video signal, and F indicates a synchronization flag.
Is a high-speed clock corresponding to video data. Also,
Is another information data such as voice data or test data, which is relatively low speed. Is a low-speed clock corresponding to audio data (test data), and is transmission data.

In the video signal shown in (1), the transmission data when the synchronization flag F is "1" is useless synchronization signal data. Therefore, as shown in, the relatively low-speed separate information data A such as audio data or test data is converted in speed and inserted by replacing it with the synchronization signal data. The transmission data that captures the information data is obtained.

Generally, the information capacity of the synchronizing signal in the video signal accounts for 5% or more. Therefore, in the case of ultra-high-speed transmission of HDTV signals (several Gb / s), for example, if the information capacity of video data is 2 Gb / s, when this portion is used for transmission of other information data, the information capacity is 100 Mb / s.
s or more can be obtained. This is a sufficient information capacity for transmission of the above-mentioned voice data and test data.

Conventionally, a transmission channel for an audio signal or the like is set separately from a video signal channel for multiplex transmission, and the transmission of a video signal is stopped when a transmission device is tested. Although the test signal is transmitted, in the method of the present invention, the audio signal channel and the test signal channel can be taken in the video signal channel. It is also possible to carry out an on-line transmission line test without requiring the.

[0020]

FIG. 3 shows an embodiment (1) of the present invention, in which the same parts as those in FIG.
Reference numeral 16 is a speed conversion circuit in the transmission device, and 28 is a speed conversion circuit in the reception device.

In the embodiment shown in FIG. 3, the speed conversion circuit 16 of the transmission device speed-converts the information data into a speed synchronized with the video data rate by using the video signal synchronizing signal as a trigger, and the multiplexing circuit. 13 multiplexes this on the video signal channel.

In the receiving device, the speed conversion circuit 28 is
With the detection of the synchronization flag in the received video data as a trigger,
The received information data is separated from the video signal channel, converted into a desired information data rate, and output.

Therefore, according to the embodiment shown in FIG.
The information data can be transmitted without stopping the transmission of the video signal.

FIG. 4 shows an embodiment (2) of the present invention, in which the same components as those in FIG. 3 are designated by the same reference numerals, and 17 is an analog / digital converter for converting an analog voice signal into digital voice data. (A / D) converter, 29
Is a digital / analog (D / A) converter for converting digital voice data into an analog voice signal.

In the embodiment shown in FIG. 4, the A / D converter 17 of the transmitter converts the analog audio signal into digital audio data, and the speed conversion circuit 16 uses the video signal synchronizing signal as a trigger. The speed of the digitized audio data is converted into a speed synchronized with the video data rate, and the multiplexing circuit 13 multiplexes the audio data into the video signal channel.

In the receiving device, the speed conversion circuit 28 is
With the detection of the synchronization flag in the received video data as a trigger,
Separate the received audio data from the video signal channel, and
The A converter 29 converts this into an analog audio signal and outputs it.

Therefore, according to the embodiment shown in FIG.
An audio signal can be transmitted without providing a channel different from the video signal channel.

FIG. 5 shows an embodiment (3) of the present invention, in which the same parts as those in FIG. 3 are indicated by the same numbers, and 18 is a PN pattern generation for generating a PN pattern for a transmission line test. Reference numeral 30 is an error detector for detecting a transmission line error by the reception PN pattern.

In the embodiment shown in FIG. 5, the PN pattern generator 18 of the transmitter generates a PN pattern for a transmission line test, and the speed conversion circuit 16 uses the video signal synchronizing signal as a trigger to generate the PN pattern. The pattern is subjected to speed conversion into a speed synchronized with the video data rate, and the multiplexing circuit 13 multiplexes this into the video signal channel.

In the receiving device, the speed conversion circuit 28 is
With the detection of the synchronization flag in the received video data as a trigger,
The reception PN pattern is separated from the video signal channel, and the error detector 30 detects a transmission line error by comparing the reception PN pattern with a predetermined PN pattern, and outputs an error rate signal.

Therefore, according to the embodiment shown in FIG.
The test data can be transmitted and the transmission line test can be performed on-line without stopping the transmission of the video signal.

In the embodiment shown in FIG. 5, P
The N pattern generator 18 and the speed conversion circuit 16 are replaced with a fixed pattern generator, and the speed conversion circuit 28 and the error detector 3 are replaced.
By replacing 0 with a fixed pattern detector, it is possible to perform a transmission path test with a fixed pattern and simplify the circuit configuration.

[0033]

As described above, according to the present invention, in the video signal information transmission system, it is possible to effectively use the unnecessary transmission data of the synchronizing signal portion in the prior art, so that the information capacity is greatly expanded. Can be realized.

Further, according to the present invention, since the audio data and the data for the transmission path test can be included in the video data channel and transmitted, the transmission channel of the audio signal and the like can be set separately from the video signal channel. You don't have to. Also,
When transmitting the test signal, it is not necessary to stop the transmission of the video signal, and the on-line transmission line test can be performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention.

FIG. 2 is a diagram for explaining the operation of the present invention.

FIG. 3 is a diagram showing an embodiment (1) of the present invention.

FIG. 4 is a diagram showing an embodiment (2) of the present invention.

FIG. 5 is a diagram showing an embodiment (3) of the present invention.

FIG. 6 is a diagram showing a conventional video signal information transmission system.

FIG. 7 is a diagram illustrating encoding of a video signal.

[Explanation of symbols]

 1 A / D conversion means 2 Synchronization detection means 3 D / A conversion means 4 Synchronization generation means 5 Speed conversion means 6 Speed conversion means 7 A / D conversion means 8 D / A conversion means 9 Pattern generation means 10 Error detection means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Miji Nishizawa, inventor Mitsuji Nishizawa 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Within Fujitsu Limited (72) Inventor Takuya Miwa 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph Phone Co., Ltd.

Claims (3)

[Claims] 1. An A / D conversion means (1) for converting an analog video signal including an analog sync signal into digital video data, and a sync detection means (2) for detecting a transmission period of the sync signal and generating a sync flag. ), A transmitter for multiplexing and transmitting the digital video data and the synchronization flag, a D / A conversion means (3) for converting the received digital video data into an analog video signal, and a reception period of the synchronization flag. A video signal transmission device comprising: a sync generation means (4) for generating an analog sync signal corresponding to the above, and a receiving device for reproducing the video signal by adding the analog sync signal to the analog video signal, The transmitting device is provided with a speed converting means (5) for converting the information data into the same speed as the video data, and the information data is transferred to the video during a sync signal transmission period. The information data is multiplexed with the data and transmitted, and the receiving device is provided with a speed converting means (6) for converting the reception information data separated from the reception signal into the original speed during the synchronization flag reception period, and the information data is transmitted. A video signal information transmission method characterized by reproducing. 2. The video signal information transmission system according to claim 1, wherein an A / D conversion means (7) for converting an analog audio signal into digital audio data and inputting it to the speed conversion means (5) in a transmission device. ) Is provided, the audio data is multiplexed with the video data and transmitted during a synchronization signal transmission period, and is separated from a reception signal during the synchronization flag reception period by the speed conversion means (6). A video signal information transmission system characterized in that the audio signal is reproduced by providing D / A conversion means (8) for converting the received audio data converted into the speed of 1. into an analog audio signal. 3. The video signal information transmission system according to claim 1, wherein the transmitting device is provided with a pattern generating means (9) for generating a test pattern and inputting it to the speed converting means (5) for synchronization. In the signal transmission period, the pattern data is multiplexed with the video data and transmitted, and the reception device separates the reception signal from the reception signal in the synchronization flag reception period and converts it into the original speed in the speed conversion means (6). A video signal information transmission system characterized in that an error detection means (10) for detecting an error in pattern data is provided to test a transmission line on-line.