JPH11331886A - Device for adjusting and discriminating reproduction characteristics of video signal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly discriminate and adjust video signal reproduction characteristics of a video device in a short time with a simple operation. SOLUTION: In the device for adjusting and discriminating a reproduction characteristics, a programmable test pattern generator 7 outputs a test pattern of a luminance signal, a red color difference signal and a blue color difference signal. A color signal conversion output circuit 10 coverts the patterns, a display device 11 displays the test patterns of the luminance signal, the red color difference signal and the blue color difference signal in a way that the screen is divided into three by the signals, an oscilloscope 12 observes an output of the color signal conversion output circuit 10 and an adjustment device 13 rewrites storage values of level setting data of the luminance signal, the red color difference signal and the blue color difference signal in a PROM 14 so that output level of the luminance signal, the red color difference signal and the blue color difference signal from the color signal conversion output circuit 10 is a reference level. Thus, it is not required to prepare a separate adjustment device and to receive an external test pattern signal, and the luminance and the chromaticity are adjusted under a prescribed condition simply, quickly and properly and a color characteristics image with high image quality is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for judging and adjusting reproduction characteristics of a video signal.

[0002]

2. Description of the Related Art In various video equipment such as a video camera, a video signal is reproduced and displayed on a display as an image. At the time of display, a high-quality image faithful in terms of luminance and chromaticity is displayed on the display. Is required to be displayed. For this purpose, a luminance test signal, a red color difference test signal and a blue color difference test signal are input to a video signal reproducing device of a video device, and the luminance of the image displayed on the display, the chromaticity of the red color difference signal, and the blue color difference signal are measured. It is necessary to determine the reproduction characteristics of the video signal reproduction device based on the chromaticity of the signal.

In order to make this determination, conventionally, a reference luminance signal is generated and input to a video reproducing apparatus, and the luminance characteristic of the video reproducing apparatus is determined based on the luminance of a reproduced image displayed on a display. A reference red difference signal is generated and input to the video playback device, and the chromaticity of the playback image displayed on the display is used to determine the redness of the video playback device. The blueness of the video playback device is determined based on the chromaticity of the playback image displayed on the display after being input to the playback device.

[0004]

In determining the reproduction characteristics of the above-mentioned conventional video signal, a reference luminance signal, a reference red difference signal, and a reference blue difference signal are generated by an external test equipment, and are sequentially determined. It is necessary to input the data to a video reproducing apparatus and determine the luminance or chromaticity of the reproduced image displayed on the display in each case. For this reason, in the above-mentioned conventional method for determining the reproduction characteristics of a video signal, it is necessary to separately prepare a test device, and the operation of the test is complicated, and the test time is long.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described current state of the method for determining the reproduction characteristics of a video signal, and has as its object to determine and adjust the video signal reproduction characteristics of a video device in a short time with a simple operation. And an apparatus for judging and adjusting the reproduction characteristic of a video signal capable of accurately performing the adjustment.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a video apparatus in which a video signal is converted by a color signal conversion output circuit and displayed on a display, and the video signal is reproduced. A test pattern signal generating means for outputting a luminance test pattern signal, a red color difference test pattern signal, and a blue color difference test pattern signal when a test mode is set; When setting the mode,
A test pattern for displaying a test pattern signal by dividing the screen of the display into three parts using the luminance test pattern signal, the red color difference test pattern signal, and the blue color difference test pattern signal output from the test pattern generating means Signal display means, and a conversion output level of the color signal conversion output circuit such that the signal levels of the luminance test pattern signal, the red color difference test pattern signal, and the blue color difference test pattern fall within a preset reference level range. Level adjusting means for performing adjustment.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a video camera will be described below with reference to FIGS. FIG. 1 is a block diagram showing a configuration of the present embodiment, and FIG. 2 is a flowchart of a conversion output level adjusting operation of the present embodiment.

In the present embodiment, the reproduction characteristic determination and adjustment device according to the present invention is incorporated in a video camera. As shown in FIG. 1, the video camera 1 is provided with a VTR chassis 8, and the VTR chassis 8 is provided. The chassis 8 includes a luminance test pattern signal 16Y and a red color difference test pattern signal 16Y.
A programmable test pattern generator 7 that outputs a test pattern image signal composed of R and blue difference test pattern signals 16B, and a VTR 5 that stores image data are accommodated. In the video camera 1, a recording system circuit 3 that performs signal processing on an image signal of a subject obtained by the imaging unit 2 and stores the signal in a VTR is connected to an imaging unit 2 that captures an image of the subject. VT for storing image signals
R5 is connected, and the VTR 5 is connected to a reproduction system circuit 6 that reads an image signal from the VTR 5 and performs signal processing for reproduction.

An output terminal of the programmable test pattern generator 7 and an output terminal of the reproduction system circuit 6 convert and output a test pattern image signal or an image signal read from the VTR 5 via a changeover switch 17. The color signal conversion output circuit 10 is connected to Further, in the present embodiment, the PROM 14 that inputs the level setting signal for setting the conversion output levels of the luminance signal, the red color difference signal, and the blue color difference signal to the color signal conversion output circuit 10 is connected to the color conversion output circuit 10. And the color signal conversion output circuit 10
Of the test pattern image signal or VTR
The display 11 on which the image signal read from the display 5 is displayed is connected. In the present embodiment, when the test mode is set, the input terminal of the oscilloscope 12 is connected to the output terminal of the color signal conversion output circuit 10,
The adjuster 13 for rewriting the level setting data of the PROM 14 is connected to the PROM 14.

The operation of adjusting the converted output level according to the present embodiment having such a configuration will be described. In step S1 of the flowchart of FIG. 2, the output level adjustment test mode is set, the changeover switch 17 is switched to the programmable test pattern generator 7 side, and the luminance test pattern signal 16Y, the red color difference test A test pattern image signal composed of the pattern signal 16R and the blue difference test pattern signal 16B is output and input to the color signal conversion output circuit 10. In the color signal conversion output circuit 10, the luminance test pattern signal 16
The Y, red color difference test pattern signal 16R, and blue color difference test pattern signal 16B are D / A converted, and the process proceeds to step S2, where the display screen is divided into three as shown in FIG. The difference signal test image 15R and the blue difference signal test image 15B are displayed on the display 11.

In step S3, the technician connects the input terminal of the oscilloscope 12 to the output terminal of the chrominance signal conversion output circuit 10, and connects the oscilloscope 12 to the luminance test pattern signal 16Y, as shown in FIG. The signal waveforms of the red color difference test pattern signal 16R and the blue color difference test pattern signal 16B are displayed, and the respective signal levels are measured. Then, the process proceeds to step S4, where the technician specifies the luminance test pattern signal 16Y and the red color difference test pattern signal 16Y displayed on the oscilloscope 12.
R and the signal waveforms of the blue difference test pattern signal 16B are observed, and based on the respective signal waveforms, the luminance test pattern signal 16Y and the red difference test pattern signal 16B are determined.
The adjustment is performed so that the output levels of the signal waveforms of the R and blue difference test pattern signals 16B become the preset reference levels, respectively.

This adjustment is performed on each test pattern signal by the adjuster 13. For example, for the luminance test pattern signal 16Y, the oscilloscope 12 adjusts the output level d of the signal waveform of the oscilloscope 12 to the reference level. While monitoring the 11 display waveforms, adjuster 1
3, the level setting data of the luminance signal stored in the PROM 14 is adjusted and rewritten. Next, the adjuster 13 monitors the display waveform of the oscilloscope 11 so that the output level d of the signal waveform of the oscilloscope 12 becomes the reference level for the red difference signal.
The level setting data of the red color difference signal stored in the PROM 14 is adjusted and rewritten. Then, while monitoring the display waveform of the oscilloscope 11 so that the output level d of the signal waveform of the oscilloscope 12 becomes the reference level for the blue difference signal, the adjuster 13 monitors the PRO.
The level setting data of the blue color difference signal stored in M14 is adjusted and rewritten.

As described above, the level setting data of the luminance signal, the level setting data of the red color difference signal, and the level setting data of the blue color difference signal stored in the PROM 14 are rewritten.
The color signal conversion output circuit 10 performs adjustment so that a luminance signal, a red difference signal, and a blue difference signal having a preset reference output level are output.

With this adjustment, a high-quality image of the subject captured by the video camera 1 can be displayed on the display 11, and an image signal of the subject captured from the imaging unit 2 is recorded by the recording system circuit 3. Is processed and stored in the VTR. During a reproduction operation, the changeover switch 17 is switched to the reproduction system circuit 6 side, and the image signal of the subject read from the VTR 5 is reproduced by the reproduction system circuit 6. Signal processing for the color signal conversion output circuit 10
The luminance signal, red color difference signal, and blue color difference signal of the image signal are respectively converted into reference output levels by a color signal conversion output circuit 10, and a captured image of a subject having excellent color characteristic quality is displayed on a display 11. Is displayed.

As described above, according to the present embodiment, the luminance test pattern signal 16 output from the programmable test pattern generator 7 in the test mode
In response to the Y, red difference test pattern signal 16R, and blue difference test pattern signal 16B, the signal output level converted and output from the color signal conversion output circuit 10 is
Observed by the oscilloscope 12. The luminance test pattern signal 16Y and the red color difference test pattern signal 16
R and the output level of the blue color difference test pattern signal 16B are respectively set to a preset reference level.
The adjuster 13 rewrites the level setting data of the luminance signal, the level setting data of the red color difference signal, and the level setting data of the blue color difference signal stored in the PROM 14. For this reason, according to the present embodiment, it is not necessary to prepare a separate adjusting device and adjust the input of a color test pattern signal from outside, and the brightness and chromaticity of the image signal can be quickly and accurately adjusted by a simple operation. By adjusting to a predetermined condition, it is possible to always display an image with high quality color characteristics on a display.

[0016]

The present invention is incorporated in a video device, and a luminance test pattern signal, a red color difference test pattern signal, and a blue color difference test pattern signal are output from a test pattern signal generating means by setting a test mode. The test pattern signal display means divides the screen into three by a luminance test pattern signal, a red color difference test pattern signal, and a blue color difference test pattern signal, and displays the test pattern signal on a display. The adjustment of the conversion output level of the signal conversion output circuit is performed such that the signal levels of the luminance test pattern signal, the red difference test pattern signal, and the blue difference test pattern fall within a preset reference level range.
Adjustment equipment does not require separate input of test pattern signals from the outside.Adjustment of brightness and chromaticity to predetermined conditions quickly and accurately by simple operation, and always display high quality image of video signal on display. It becomes possible to do.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a flowchart of an operation of adjusting a converted output level according to the embodiment;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Video camera, 7 ... Programmable test pattern generator, 10 ... Color signal conversion output circuit, 11 ... Display, 12 ... Oscilloscope, 13 ... Adjuster, 14 ... PR
OM.

Claims (1)

[Claims] 1. A video signal reproduction characteristic determining and adjusting device incorporated in a video device which converts a video signal by a color signal conversion output circuit and displayed on a display, and determines and adjusts the reproduction characteristic of the video signal. A test pattern signal generating means for outputting a luminance test pattern signal, a red color difference test pattern signal, and a blue color difference test pattern signal when a test mode is set; and the luminance test output from the test pattern generating means when a test mode is set A pattern signal, the red difference test pattern signal, and the blue difference test pattern signal, by dividing the screen of the display into three, and displaying a test pattern signal; and a luminance test pattern signal; A red difference test pattern signal and the blue difference test pattern And a level adjustment means for adjusting the conversion output level of the color signal conversion output circuit so that the signal level of the video signal falls within a preset reference level range.