JPH06169473A - Video signal correcting device - Google Patents

Abstract

PURPOSE:To detect a synchronizing signal at the time of reproducing to suppress the disturbance of synchronism by limiting the data change or generation processing so that the level of a color composite video signal is not lower than a synchronizing tip level. CONSTITUTION:The luminance signal and the color signal read out from a recording medium 1 are demodulated by demodulating circuits 2 and 3, and the luminance level and the color level are detected by detecting circuits 4 and 5 and are sent to a level control circuit 6. The control circuit 6 adjusts the color signal level by a level adjusting circuit 7 if the decoded widen signal obtained by adding both signals in an adding circuit 9 has the level lower than the synchronizing tip level. Then, the synchronizing signal from a synchronizing signal generating circuit 8 is added to the video signal of the adding circuit 9 by an adding circuit 10 to output a composite video signal. Thus, the synchronizing signal is detected even when the luminance signal and the color signal are changed by a personal computer or the like, and the disturbance of synchronism is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal correction device, and more particularly to a video signal correction device that does not affect the synchronization of video signals even when image data is modified.

[0002]

2. Description of the Related Art In a video device such as a video tape recorder or a still video, for example, an input video signal is separated into a luminance signal and a chrominance signal, or a predetermined modulation is performed on the separated and inputted luminance signal and chrominance signal. And recording on a recording medium. That is, in the video tape recorder, the Y signal separated from the video signal by the Y / C separation circuit is frequency-modulated, the C signal is converted into a low frequency band, and the signals after both processes are added to record on a video tape or the like. Record on media. Further, in the still video recorder, the Y and C signals separated from the video signal by the Y / C separation circuit are subjected to color difference conversion, and then the signals are subjected to frequency modulation processing and then added to a recording medium such as a video floppy. Record. In such a video device, the signal at the time of recording is an analog signal, and the recorded content is hardly rewritten by directly operating the signal recorded on the recording medium.

By the way, in recent years, a system for recording an image as digital data has been used in various fields. For example, SMC (Solid state Memory Camera) that applies a solid-state memory card as a recording medium for image information
Then, the trend of recent years is to make the format of the image data stored in the recording medium compatible with the data of a personal computer (PC). This way,
On the personal computer side, the image data recorded in the solid-state memory card can be modified and manipulated by the SMC just like the personal computer data. That is, originally, the brightness, chromaticity (hue / saturation), etc. of the image recorded in the solid-state memory card by the SMC can be independently set arbitrarily.

[0004]

As described above, in the conventional video apparatus, the image data is processed as digital data, and various modification operations can be performed.
On the other hand, when reproducing the image data stored in a recording medium such as a solid-state memory card as digital data on a TV monitor, in order to obtain a reproducible color composite video signal, the read image data is D / A conversion is performed and a sync signal is added. As is well known, the TV monitor cannot reproduce the signal as an image on the screen unless the synchronization signal in the supplied signal can be detected properly. However, if the brightness, chromaticity (hue / saturation), etc. of the image recorded in the solid-state memory card as described above are arbitrarily modified by a personal computer without paying special attention,
For example, when only the color saturation (saturation) is significantly increased, the color composite video signal read out for reproduction, D / A converted, and added with a sync signal is a luminance signal level. On the other hand, the amplitude of the color subcarrier superimposed on this becomes too large, and the lower limit level of the composite video signal falls below the sync tip level (sync signal level), and a normal sync signal cannot be detected, and There is a risk that it will not be possible to reproduce. This is because the phenomenon that the luminance level is correspondingly high and only the amplitude of the color subcarrier is large cannot occur when the video signal obtained during normal imaging has high color saturation. Although it does not occur, the signal formed by the processing in the personal computer does not depend on such a physical phenomenon, and the color saturation can be arbitrarily set independently of the luminance level. Further, the signal formed by the processing by the personal computer may become a video signal in which the luminance signal level itself falls below the sync tip level.

For example, as shown in FIG. 13, when a luminance signal (A), a color signal (B) and a synchronization signal (C) are added to generate a composite signal (D), the luminance signal (A) remains unchanged. Then, if the color signal (B) is increased only by the shaded portion, the shaded portion of the obtained composite video signal (D) is expanded, and the level portion N becomes lower than the sync signal tip level, which makes synchronization detection difficult. , The screen is out of sync. As a result of modifying the image data in this way, or creating the image data by the personal computer itself without using the image pickup means, the normal sync signal cannot be detected and the image data is displayed on the TV.
There is a problem that it cannot be reproduced on the monitor, or that synchronization cannot be achieved during dubbing. In this case, it is not only difficult to confirm the outline of the image, but it may be mistakenly recognized that a defect has occurred in the signal reproduction system from the information recording medium to the TV monitor. Further, when an image formed by processing by a personal computer is to be copied to a tape by a recording device such as a VTR, if the sync signal is not detected from the recording medium of the copy source, the tape is run or rotated on the recording device side. There is also a problem that the servo for driving the head cylinder is lost.

Therefore, an object of the present invention is to provide a video signal correction apparatus which does not cause a problem in the detection of the synchronization signal when the image signal is modified.

[0007]

In order to solve the above-mentioned problems, a video signal correction apparatus according to the present invention corresponds to the first data and the chromaticity signal corresponding to the luminance signal which is an element of the color composite video signal. A video signal processing system capable of performing modification or formation processing of the second data which does not depend on each other, and is based on a result value of the first data and the second data processed by the system. It is configured to include a limiting unit that limits the modification or formation process so that the level of the color composite video signal configured as described above does not fall below the sync chip level.

[0008]

According to the present invention, for example, in a video signal processing system capable of performing data modification or formation processing on a luminance signal and a chromaticity signal forming a color composite video signal without depending on each other, these processed luminances are processed. Signal and the chromaticity signal, the level of the color composite video signal does not interrupt the sync tip level so that the modification or formation process is restricted so that the sync signal is detected. I tried not to occur.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention performs level adjustment processing on a luminance signal and a chrominance signal in order to prevent interruption of the sync tip level (synchronization signal level) of the composite image signal. FIG. 1 is a configuration block diagram showing an embodiment of a video signal correction apparatus according to the present invention, and an IC card 10 as a recording medium.
After performing a predetermined editing process on the image signal (luminance signal and color difference signal) read from No. 1, when the relationship between both signal levels is not normal and there is a risk that the composite video signal may fall below the sync tip level, In this example, the image signal is subjected to level adjustment processing and stored in another IC card 112. The compressed luminance signal and color difference signal read from the IC card 101 are decompressed by the decompression circuits 102 and 103, and then edited by the editing circuits 104 and 105.
The level information of the luminance signal level and the color difference signal level thus edited is detected by the luminance level detection circuit 106 and the color level detection circuit 107. The level control circuit 108 determines whether or not the relationship between the luminance level and the color level is normal, that is, whether or not the composite video signal composed of both signals interrupts the sick chip level. here,
When it is determined that the color difference signal from the editing circuit 5 is not normal, the level adjustment circuit 109 performs a predetermined level adjustment on the color difference signal from the editing circuit 5 to prevent the interruption, and eliminates a problem in detecting the synchronization signal. The luminance signal and the color difference signal thus obtained are respectively compressed by the compression circuits 110 and 111, and the IC
It is recorded on the card 112.

FIG. 2 is a flowchart showing the operation processing procedure of the embodiment shown in FIG. First, the luminance signal data and the color signal data (image data) are read from the IC card (step S1), and it is determined whether the read data is compressed data or uncompressed data (step S2). If it is determined that the data is compressed data, after decompression processing is performed (step S
3) Also, if it is determined that the data is uncompressed data,
Edit processing such as modification of brightness / color data is performed (step S
4) It is determined whether the relationship between the brightness level and the color level is normal (step S5). If it is determined in step S5 that it is not normal, for example, the color level is adjusted (step S9), and if it is determined that it is normal, it is determined whether or not to compress the data. When it is compressed, the compression process is performed (step S7), and when it is not compressed, the data is recorded on the IC card as it is (step S8).

The specific configuration of the video signal correction apparatus according to the present invention will be described below. FIG. 3 is a configuration block diagram showing a concrete first embodiment of the video signal correction apparatus according to the present invention. A luminance signal and a color signal are stored in the recording medium 1, and the luminance signal and the color signal read from the recording medium 1 are demodulated by the demodulation circuits 2 and 3, respectively. The demodulated brightness signal and color signal are detected in brightness level and color level by the brightness level detection circuit 4 and the color level detection circuit 5, and are sent to the level control circuit 6. The level control circuit 6 determines whether or not the relationship between the detected luminance level and color level is normal, that is, whether or not the composite video signal obtained by adding both signals interrupts the sync tip level. to decide. If it is determined that the color signal level from the demodulation circuit 3 is not normal, the level adjustment circuit 7
Adjust by. When it is determined that the level is normal, the level adjustment circuit 7 controls so that the level adjustment is not performed. The adder circuit 9 adds the luminance signal output from the demodulation circuit 2 and the color signal from the level adjustment circuit 7.
The adder circuit 10 adds the sync signal from the sync signal generation circuit 8 to the output signal from the adder circuit 9 and outputs a composite video signal.

FIG. 9 is a waveform diagram for explaining the processing in the first embodiment. In FIG. 9, when the level relationship between the color signal (A) indicated by the broken line and the luminance signal is not normal, the level is adjusted by the level adjusting circuit 7 as indicated by the solid line, and the obtained composite video signal (B) is the synchronization signal. Beyond the level, I try not to interrupt. In the configuration of FIG. 3, since only the color signal level is adjusted, the circuit scale can be reduced and there is no effect on the luminance signal.

FIG. 4 is a block diagram showing a second embodiment of the video signal correction apparatus according to the present invention. In the embodiment shown in FIG. 3, when the luminance level and the color level are not in a normal relationship, the color signal from the demodulation circuit 3 is subjected to the level adjustment processing, whereas the present embodiment does not The difference is that a level adjusting circuit 11 that performs a level adjusting process on the luminance signal from the circuit 2 is provided. For example, the dotted line portion of the luminance signal (A) in FIG. 10 is raised and the level is adjusted as shown by the solid line to prevent the composite video signal (B) from interrupting the sync signal. In the present embodiment, since only the luminance signal level is adjusted, it is possible to obtain a video signal correction device having a small circuit scale that does not affect the color signal.

FIG. 5 is a block diagram showing a third embodiment of the video signal correction apparatus according to the present invention. This embodiment is a combination of the structures shown in FIGS. 3 and 4, and when the brightness level and the color level are not in a normal relationship, as shown in FIG. Level adjustment is performed on A) and the color signal (B), and the signal shown by the solid line is obtained to obtain the composite video signal (C). According to the present embodiment, the luminance signal, the color signal, and both signals are adjusted, so that finer adjustment can be performed.

FIG. 6 is a block diagram showing a fourth embodiment of the video signal correction apparatus according to the present invention. In this embodiment, the luminance signal and the color signal from the demodulation circuits 2 and 3 are added by the adder 9 without performing the level detection of the luminance signal and the color signal, and the added signal is uniformly leveled to interrupt the sync signal level. A slicer circuit 12 for slicing is provided. For example, as shown in FIG. 12, a sync signal generated from the sync signal generating circuit 8 is added to a signal (B) obtained by slicing the addition signal (A) of the luminance signal and the color signal at the slice level TH. The composite video signal (C) is obtained. In this embodiment, the level detector is not necessary and the structure is extremely simplified.

FIG. 7 is a block diagram showing the configuration of a fifth embodiment of the video signal correction apparatus according to the present invention when it is applied to an SMC system. IC card 21 which is a recording medium
The compressed luminance signal and color-difference signal recorded in 1 are subjected to decompression processing by decompression circuits 22 and 23, and converted into analog signals by D / A converters 24 and 25. The analog color difference signal from the D / A converter 25 is sent to the encoder 26.
Are converted into color signals by. Brightness level detection circuit 27
Detects the level of the luminance signal from the D / A converter 24. Further, the level of the color signal from the encoder 26 is detected by the color level detection circuit 28. The control circuit 29 determines whether the relationship between the luminance signal level and the color signal level thus detected is normal. Here, if it is determined that it is not normal, the level adjustment circuit 30 causes
The color signal from the encoder 26 is level-adjusted and sent to the adder 32. The adder 32 adds the luminance signal from the D / A converter 24 and the chrominance signal from the level adjusting circuit 30, and further adds the luminance signal from the synchronizing signal generating circuit 31 by the adder 33 to obtain a composite video image. The signal is output.

FIG. 8 is a block diagram showing the configuration of another embodiment of the present invention. In the embodiment of FIG. 7, the level adjustment is performed after conversion to analog signals by the D / A converters 24 and 25, but in the present embodiment, the expansion circuit 22 before conversion by the D / A converters 24 and 25. The luminance level and the color level are detected on the basis of the signals from the signals 23 and 23, and the normality of the relationship between the two levels is judged. When they are not normal, the level adjustment circuit 30 performs the level adjustment. Although SMC has been described in the above embodiments, the present invention can of course be applied to the case where a magnetically recorded medium is used.

[0018]

As described above, according to the video signal correction apparatus of the present invention, the color composite video signal level does not fall below the sync signal and sync chip level, and is modified into a luminance signal and a color signal by a personal computer or the like. Even if is added, the sync signal can be detected at the time of reproduction, and the disturbance of synchronization at the time of TV monitor reproduction or dubbing is eliminated.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a first embodiment of a video signal correction device according to the present invention.

FIG. 2 is a configuration block diagram of a second embodiment of a video signal correction device according to the present invention.

FIG. 3 is a specific first example of a video signal correction apparatus according to the present invention.
It is a configuration block diagram of an embodiment of.

FIG. 4 is a configuration block diagram of a second embodiment of a video signal correction device according to the present invention.

FIG. 5 is a configuration block diagram of a third embodiment of a video signal correction device according to the present invention.

FIG. 6 is a configuration block diagram of a fourth embodiment of a video signal correction device according to the present invention.

FIG. 7 is a configuration block diagram showing an application example of an image signal correction apparatus according to a fifth embodiment of the present invention to an SMC system.

FIG. 8 is a configuration block diagram of an application example of a video signal correction device according to a sixth embodiment of the present invention to an SMC system.

9 is a waveform diagram illustrating the operation of the embodiment of FIG.

10 is a waveform diagram illustrating the operation of the embodiment of FIG.

9 is a waveform diagram illustrating the operation of the embodiment of FIG.

FIG. 12 is a waveform diagram illustrating the operation of the embodiment of FIG.

FIG. 13 is a diagram for explaining a problem that a composite video signal in a conventional video device interrupts a synchronization signal.

[Explanation of symbols]

 1 recording medium 2,3 demodulation circuit 4,27,106 luminance level detection circuit 5,28,107 color level detection circuit 6,29,108 level control circuit 7,11,30,109 level adjustment circuit 8,31 sync signal generation Circuits 9, 10, 32, 33 Adder circuits 21, 101, 112 IC cards 22, 23, 102, 103 Expanding circuits 24, 25 D / A converters 110, 111 Compressing circuits 104, 105 Editing circuits

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[Procedure amendment]

[Submission date] October 6, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a first embodiment of a video signal correction device according to the present invention.

FIG. 2 is a configuration block diagram of a second embodiment of a video signal correction device according to the present invention.

FIG. 3 is a specific first example of a video signal correction apparatus according to the present invention.
It is a configuration block diagram of an embodiment of.

FIG. 4 is a configuration block diagram of a second embodiment of a video signal correction device according to the present invention.

FIG. 5 is a configuration block diagram of a third embodiment of a video signal correction device according to the present invention.

FIG. 6 is a configuration block diagram of a fourth embodiment of a video signal correction device according to the present invention.

FIG. 7 is a configuration block diagram showing an application example of an image signal correction apparatus according to a fifth embodiment of the present invention to an SMC system.

FIG. 8 is a configuration block diagram of an application example of a video signal correction device according to a sixth embodiment of the present invention to an SMC system.

9 is a waveform diagram illustrating the operation of the embodiment of FIG.

10 is a waveform diagram illustrating the operation of the embodiment of FIG.

11 is a waveform diagram illustrating the operation of the embodiment of FIG.

FIG. 12 is a waveform diagram illustrating the operation of the embodiment of FIG.

FIG. 13 is a diagram for explaining a problem that a composite video signal in a conventional video device interrupts a synchronization signal.

[Description of Reference Signs] 1 recording medium 2,3 demodulation circuit 4,27,106 luminance level detection circuit 5,28,107 color level detection circuit 6,29,108 level control circuit 7,11,30,109 level adjustment circuit 8 , 31 Synchronous signal generating circuit 9, 10, 32, 33 Adder circuit 21, 101, 112 IC card 22, 23, 102, 103 Expanding circuit 24, 25 D / A converter 110, 111 Compressing circuit 104, 105 Editing circuit

Claims (1)

[Claims] A video signal processing system capable of modifying or forming data without depending on the first data corresponding to the luminance signal and the second data corresponding to the chromaticity signal, which are elements of the color composite video signal. In order to prevent the level of the color composite video signal formed based on the result values of the first data and the second data processed by the system from falling below the sync tip level, A video signal correction apparatus comprising a limiting means for limiting the forming process.