JPH05336489A - Method and circuit for generating advanced black burst signal - Google Patents

Abstract

PURPOSE:To realize the circuit generating the advanced black burst signal from a black burst signal with simple circuit composition. CONSTITUTION:The advanced black burst signal generating circuit is provided with a synchronizing separator circuit 10, an external synchronous horizontal/ vertical synchronizing signal generating circuit 12, a delay circuit 14, and an encoder circuit 16. The synchronizing separator circuit 10 synchronizes and separates an input black burst signal BB, generating a vertical synchronizing signal VSYNC and a horizontal/vertical composite synchronizing signal ESYNC. The delay circuit 14 delays the vertical synchronizing signal VSYN by a period of time so as to make it the advanced black burst signal equivalent. The vertical synchronous horizontal/vertical synchronizing signal generating circuit 12 generates a horizontal/vertical composite synchronizing signal ESYNC based on the delay vertical synchronizing signal DVSYNC from the delay circuit 14. The encoder circuit 16 generates the advanced black burst signal ABB by decoding the horizontal/vertical composite synchronizing signal ESYNC.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit for generating a black burst signal used when operating a video signal reproducing apparatus and a video signal recording apparatus in synchronism in a video signal processing system for business use. In particular, when an intermediate video signal processing device is provided between a video signal reproducing device and a video signal recording device, a black burst signal considering a time delay due to signal processing in the intermediate video signal processing device. Relating to a circuit for generating.

[0002]

2. Description of the Related Art FIG. 3 shows a general configuration of a video signal reproduction processing system for business use. This video signal reproduction processing system is a video signal reproduction device 50 for reproducing a video signal, and an intermediate video signal processing device for performing predetermined signal processing, for example, processing for adding a title to the reproduction video signal from the video signal reproduction device 50. 52, a video signal recording device 54 for recording the video signal processed by the intermediate video signal processing device 52.

In this video signal reproduction processing system, it is necessary to record the video signal reproduced by the video signal reproducing device 50 in the video signal recording device 54 at an accurate timing. Therefore, the black burst signal BB indicating the time delay associated with the recording process of the video signal recording device 54.
Is output to the video signal reproducing device 50. black·
The burst signal BB is a black signal as a video signal, that is, a black signal that does not appear on the screen when an image is reproduced is generated as a burst wave for synchronous pull-in. When signal processing is performed by the signal processing circuit 521 in the intermediate video signal processing device 52, processing time is further delayed. Therefore, in consideration of the fact that the black burst signal BB from the video signal recording device 54 is further delayed in the intermediate video signal processing device 52 by the processing time of the intermediate video signal processing device 52, the black burst signal BB is preliminarily taken in advance. Advanced black burst signal generation circuit 523 for generating a black burst signal, that is, an advanced black burst signal ABB
Is provided.

Advanced black burst signal AB
B is fed back to the video signal reproducing apparatus 50, and the video signal reproducing apparatus 50 reproduces and outputs the video signal in consideration of the prefetch time, so that the signal processing is synchronized throughout the entire video signal reproducing processing system.

FIG. 4 shows a configuration example of the advanced black burst signal generation circuit 523 in the intermediate video signal processing device 52 shown in FIG. This advanced black burst signal generation circuit is composed of a sync separation circuit 70, an external synchronization type horizontal / vertical sync signal generation circuit 72, a continuous wave generation circuit 74,
It has a first counter 76, a second counter 78, a third counter 80, a memory 82, and a D / A converter and encoder circuit 84. The sync separation circuit 70 receives the black burst signal BB shown in FIG. 5 (A) output from the video signal recording device 54 and inputs the vertical sync signal VSYNC.
C is separated and a horizontal / vertical composite sync signal ESYNC is generated. The external synchronization type horizontal / vertical synchronization signal generation circuit 72 includes a horizontal / vertical composite synchronization signal ESYNC and a vertical synchronization signal VSY.
NC is input and a plurality of horizontal synchronizing signals HSYNC are generated using the vertical synchronizing signal VSYNC as a reference for one frame. The continuous wave generating circuit 74 is composed of, for example, a PLL, and generates a continuous wave CW shown in FIG. 5B with reference to the horizontal synchronizing signal HSYNC generated by the external synchronizing type horizontal / vertical synchronizing signal generating circuit 72. ..

The first counter 76 is a binary counter and counts the continuous wave CW from the continuous wave generating circuit 74. The second counter 78 is also a binary counter and counts the horizontal synchronizing signal HSYNC from the external synchronizing type horizontal / vertical synchronizing signal generating circuit 72. The third counter 80 is also a binary counter and counts the vertical sync signal VSYNC from the sync separation circuit 70. The memory 82 receives the first address signal S76 from the first counter 76, the second address signal S78 from the second counter 78, and the third address signal S80 from the third counter 80 as an address signal. , And outputs the data in the memory specified by these addresses. The first address signal S76 counting the continuous wave CW indicates the lowest address, the second address signal S78 counting the horizontal synchronizing signal HSYNC indicates an intermediate address, and the vertical synchronizing signal VS.
The third address signal S80 counting YNC indicates the highest address. The memory 82 stores pattern data for the advanced black burst signal in which a delay in the signal processing circuit 521 is added according to these address signals.

By continuously applying the first address signal S76, the pattern data of the black burst signal BB for one horizontal period is continuously output from the memory 82.
When the second address signal S78 advances by one, the pattern data of the black burst signal for the next horizontal scanning line is output according to the change of the first address signal S76. When the third address signal S80 advances, the horizontal scanning line and the black burst signal pattern in each horizontal scanning line corresponding to the field are stored in the memory 82.
Is output from. D / A converter and encoder circuit 8
Reference numeral 4 converts the data output from the memory 82 into an analog signal, encodes it, and outputs it as a continuous advanced black burst signal ABB to the video signal reproducing apparatus 50 shown in FIG. The operation timing of the above-described advanced black burst signal generation circuit is shown in FIG.

[0008]

The advanced black burst signal generating circuit shown in FIG. 4 generates a continuous wave CW that is an integral multiple of the frequency of the horizontal synchronizing signal HSYNC.
A continuous wave generating circuit 74 including LL and the like and a memory 82 for storing the advanced black burst signal pattern data are required, which causes a problem that the circuit configuration is complicated. The price is also high due to the complexity of the circuit configuration. Further, when a high frequency signal is output from the continuous wave generation circuit, it causes noise.

Therefore, it is an object of the present invention to realize the above-described advanced black burst signal generating circuit with a simpler circuit configuration and reduce the cost.

[0010]

In order to solve the above problems and achieve the above-mentioned object, according to the present invention, the vertical synchronizing signal is delayed by a time corresponding to the delay time in the video signal processing system and is equivalent. There is provided an advanced black burst signal generation method for generating an advanced black burst signal that is advanced by a delay time.

Further, according to the present invention, a sync separation circuit for inputting a black burst signal to generate a horizontal and vertical composite sync signal and separating the vertical sync signal, and a delay for delaying the separated vertical sync signal for a predetermined time. Circuit, an external synchronous horizontal / vertical synchronous signal generating circuit for generating a second horizontal / vertical composite synchronous signal based on the timing of the delayed vertical synchronous signal from the delay circuit, and an external synchronous horizontal / vertical synchronous signal generating circuit There is provided an advanced black burst signal generation circuit having an encoder circuit for decoding a horizontal / vertical composite sync signal and generating an advanced black burst signal. Specifically, in a video signal reproduction processing system including a video signal reproduction device, an intermediate video signal processing device, and a video signal recording device, the advanced black burst signal generation circuit is arranged in the intermediate video signal processing device. The advanced black burst signal is output in response to the black burst signal from the video signal recording device.

Further, according to the present invention, there is provided a sync reference signal generating circuit for inputting a signal including a sync signal indicating a basic processing delay state and outputting an advanced sync signal in consideration of a predetermined processing time delay. A circuit for separating the sync signal, a circuit for delaying the sync separation signal for a predetermined time,
Based on the delay synchronization signal from the predetermined time delay circuit,
There is provided a sync reference signal generation circuit having a circuit for outputting a horizontal / vertical composite sync signal and a circuit for decoding the horizontal / vertical composite sync signal from the circuit to generate a second sync reference signal.

[0013]

The vertical synchronizing signal is delayed by a time corresponding to the delay time in the video signal processing system, and an advanced black burst signal advanced equivalently by the delay time is generated. This advanced black burst signal generation can be realized with a simple circuit configuration such as a sync separation circuit, an external sync type horizontal / vertical sync signal generation circuit, a delay circuit, and an encoder circuit.

[0014]

1 is a circuit diagram of an advanced black burst signal generation circuit as an embodiment of a synchronization reference signal generation circuit of the present invention. The advanced black burst signal generation circuit is the intermediate video signal processing device 52 shown in FIG.
Advanced black burst signal generation circuit 52 in
3, and the video signal recording device 54 shown in FIG.
Input the black burst signal BB output from the device, and input the advanced black burst signal ABB as shown in FIG.
To the video signal reproducing device 50 shown in FIG. This advanced black burst signal generation circuit is composed of a sync separation circuit 10, an external sync type horizontal / vertical sync signal generation circuit 12, a delay circuit 14, and an encoder circuit 16.

The sync separation circuit 10 includes a video signal recording device 54.
2B. The black burst signal BB output from FIG.
YNC and vertical sync signal VSYNC are output. The black burst signal BB is supplied to the video signal recording device 54 by the vertical synchronizing signal V for a time delayed by the video signal recording device 54.
It is superimposed as a burst signal at a position deviated from SYNC. The delay circuit 14 delays the vertical sync signal VSYNC shown in FIG. 2B from the sync separation circuit 10 by a time corresponding to the delay time processed by the processing circuit 521 in the intermediate video signal processing device 52, as shown in FIG. The delayed vertical synchronizing signal DVSYNC shown in FIG.

The advanced black burst signal ABB is not actually a signal for prefetching the field, but is actually a prefetching black burst signal for enabling synchronization processing in a state delayed by one field. .. Therefore, the delay circuit 14 delays the black burst signal BB from the video signal recording device 54 in consideration of the delay of the processing circuit 521 so as to be the prefetch timing in the next field. The delay circuit 14 can be composed of a plurality of stages of shift registers, counters, and the like.

External synchronization type horizontal / vertical synchronization signal generation circuit 12
The delayed vertical synchronizing signal DVSYNC and the horizontal and vertical composite synchronizing signal SYNC are input to the delay vertical synchronizing signal DVSYNC.
The horizontal / vertical composite sync signal ESYNC is output with reference to the NC timing. The encoder circuit 16 decodes the horizontal / vertical composite synchronizing signal ESYNC from the external synchronizing type horizontal / vertical synchronizing signal generating circuit 12, and outputs the advanced black burst signal ABB shown in FIG. 2D to the video signal reproducing apparatus shown in FIG. Output to 50.

The video signal reproducing device 50 outputs the reproduced video signal signal VIDEO to the intermediate video signal processing device 52 with reference to the advanced black burst signal ABB delayed by one field. The processing circuit 521 in the intermediate video signal processing device 52 performs a predetermined process and outputs the delayed delayed reproduction video signal signal DVIDEO to the video signal recording device 54. The video signal recording device 54 uses the delayed reproduction video signal signal DV.
The intermediate video signal processing device 5 outputs the black burst signal BB in which the IDEO is input and recorded, and the delay time of its own is taken into consideration.
Output to 2. The advanced black burst signal generation circuit 523 in the intermediate video signal processing device 52 performs the above-mentioned processing to perform the advanced black burst signal ABB.
Is output to the video signal reproducing device 50. As described above, synchronized video signal processing can be performed through the video signal reproducing device 50, the intermediate video signal processing device 52, and the video signal recording device 54.

Comparing the advanced black burst signal generation circuit of FIG. 1 with the advanced black burst signal generation circuit of FIG. 4, although the functions are exactly the same, the advanced black burst signal generation circuit shown in FIG. The circuit configuration of the circuit is simple without the need for the continuous wave generating circuit 74 and the memory 82. Therefore, the size can be reduced and the price can be reduced. There is also no problem of noise associated with high frequencies.

In the above embodiment, the sync signal is black.
The case where the burst signal BB and the advanced black burst signal ABB are used has been described, but as a method for synchronizing the video signal reproducing device 50, the intermediate video signal processing device 52, and the video signal recording device 54, the black burst signal However, the synchronization signals of other patterns can be used. In that case, the encoder circuit 16 shown in FIG. 1 may be replaced with one that generates desired pattern data.

[0021]

According to the present invention, a circuit for generating a continuous wave having an integral multiple of the frequency of the horizontal synchronizing signal and a memory in which a time-series pattern of the horizontal and vertical synchronizing signals are written are not required, unlike the prior art. The circuit configuration is simple and can be realized at low cost. In addition, noise is reduced because a continuous wave that is an integral multiple of the frequency of the horizontal synchronizing signal is not used.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of an embodiment of an advanced black burst signal generation circuit as an embodiment of a synchronization reference signal generation circuit of the present invention.

FIG. 2 is an operation timing chart of the advanced black burst signal generation circuit shown in FIG.

FIG. 3 is a configuration diagram of a video signal processing system in which the advanced black burst signal generation circuit of FIG. 1 is arranged.

FIG. 4 is a circuit configuration diagram of an advanced black burst signal generation circuit as a prior art.

5 is an operation timing chart shown in FIG.

[Explanation of symbols]

10. Synchronous separation circuit 12. External synchronous horizontal / vertical synchronizing signal generation circuit 14. Delay circuit 16 Encoder circuit 50. Video signal reproducing device 52. Intermediate video signal processing device 521 .. Video signal processing circuit 523 ... Advanced black burst signal generation circuit 54 ... Video signal recording device 70 ... Sync separation circuit 72 ... External synchronization type horizontal / vertical sync signal generation circuit 74 ... Continuous wave generation circuit 76 ... First counter 78 ..Second counter 80..Third counter 82..Memory 84..D / A converter and encoder circuit

Claims (4)

[Claims] 1. A method of generating an advanced black burst signal for delaying a vertical synchronizing signal by a time corresponding to a delay time in a video signal processing system, and generating an advanced black burst signal equivalently advanced by the delay time. .. 2. A sync separating circuit for inputting a black burst signal to generate a horizontal and vertical composite synchronizing signal and separating the vertical synchronizing signal, a delay circuit for delaying the separated vertical synchronizing signal for a predetermined time, and a delay circuit. And a horizontal / vertical composite sync signal from the external synchronous horizontal / vertical sync signal generation circuit for generating a second horizontal / vertical composite sync signal based on the timing of the delayed vertical sync signal from Advanced black burst signal generation circuit having an encoder circuit that decodes the signal to generate an advanced black burst signal. 3. A video signal reproduction processing system comprising a video signal reproduction device, an intermediate video signal processing device, and a video signal recording device, wherein the advanced black burst signal generation circuit is provided in the intermediate video signal processing device. The advanced black burst signal generating circuit according to claim 2, wherein the advanced black burst signal is output in response to the black burst signal from the video signal recording device. 4. A synchronization reference signal generation circuit for inputting a signal including a synchronization signal indicating a basic processing delay state and outputting an advanced synchronization signal in consideration of a predetermined processing time delay. A circuit for separating, a circuit for delaying the synchronization separation signal for a predetermined time, and a circuit for delaying the synchronization signal from the predetermined time delay circuit as a reference,
A sync reference signal generation circuit having a circuit for outputting a horizontal / vertical composite sync signal and a circuit for decoding the horizontal / vertical composite sync signal from the circuit to generate a second sync reference signal.