KR0146803B1 - Image line signal waveform analysis device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for analyzing waveforms of video signals input to a television (TV), video tape recorder (VTR), a camera, and the like. The present invention relates to a still image stored in a memory at a high sampling rate at a high speed. By displaying on a monitor and selecting a line to be analyzed on the screen, the waveform of the selected line signal of the video screen can be analyzed while viewing the image directly on the screen.

Description

Image line signal waveform analysis device

1 is a circuit block diagram of a conventional image line signal waveform analysis device.

2 is a circuit block diagram of an image line signal waveform analysis apparatus according to the present invention.

3 is a state diagram of a video signal displayed on the monitor shown in FIG. 2 according to the present invention.

* Explanation of symbols for main parts of the drawings

21: I / O border 31: Delay line

32: A / D converter 33: memory

34: central processing unit 35: computer monitor

41: synchronous separation circuit 42: scanning line counter

43: comparator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for analyzing waveforms of video signals input to a television (TV), video tape recorder (VTR), camera, and the like. Particularly, the present invention relates to a high speed processing of a video line signal at a sampling rate of An image line signal waveform stored in a memory and displayed on a monitor so as to select a line to be analyzed on the screen so that the image can be analyzed directly on the screen while analyzing the waveform of the selected line signal among the image screens. It relates to an analysis device.

In general, by analyzing an image waveform using a device that analyzes the waveform of an image signal input to a TV, a video tape recorder, a camera, or the like, the cause of diagnosis and distortion of the image, etc. Elimination measures can be prepared.

FIG. 1 is a circuit block diagram of a conventional video line signal waveform analyzing apparatus. Referring to FIG. 1, the conventional waveform analyzing apparatus has a line selection function of an image signal which is an analog input signal source, so that the signal component can be analyzed. . However, there has been a problem that the analyst cannot confirm the image formed by the signal source.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, and to provide an image line signal waveform analysis device capable of selectively analyzing a high speed processed image line signal at a high sampling rate of 100 MHz. .

Another object of the present invention is to display a still image on a monitor and select a line to be analyzed on the screen, so that the waveform of the selected line signal among the image screens can be read from the memory and analyzed while viewing the image directly on the screen. An image line signal waveform analysis apparatus is provided.

As a technical means for achieving the above object,

The present invention

An input / output borderer for receiving a composite video signal and outputting the frame to the central processing unit one frame at a time;

A delay line for delaying and outputting the line signal of the composite video signal by one horizontal scanning time;

An A / D converter for converting the output signal of the delay line into a digital signal;

A memory for storing the output signal of the A / D converter when a write enable signal is input;

The video signal of one frame and the output signal of the memory are processed and output to the monitor, and if an arbitrary horizontal line is selected for analysis on the still image displayed on the monitor, it corresponds to the horizontal line. A central processing unit for outputting a line value;

A monitor displaying a screen and a line waveform output from the central processing unit;

A synchronization separating circuit unit for separating a horizontal synchronization signal and a vertical synchronization signal of the composite video signal;

A scan line counter for counting a horizontal scan line using the horizontal sync signal of the synchronous separation circuit unit and outputting the count value;

Comparing the line value output from the central processing unit and the count value output from the scanning line counter and outputs the write enable signal when the same.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

2 is a circuit block diagram of an image line signal waveform analyzing apparatus according to the present invention.

21 is an input / output border, which receives a composite video signal and outputs one frame to the central processing unit. 31 is a delay line, which is output by delaying the line signal of the composite video signal by one horizontal scanning time. 32 is an A / D converter, which converts the output signal of the delay line into a digital signal. 33 is a memory, which stores the output signal of the A / D converter when a write enable signal is input.

34 is a central processing unit, which selects an arbitrary horizontal line for analysis on a still image displayed on a monitor, outputs a line value corresponding to the horizontal line, and outputs an input / output border output signal and a memory output signal. To process 35 is a computer monitor, which displays screen and line waveforms output from the central processing unit.

41 is a synchronous separation circuit section, which separates the vertical synchronous signal of the horizontal synchronous signal of the composite video signal. 42 is a scan line counter, which counts the horizontal scan line using the horizontal synchronization signal of the synchronous separation circuit section and outputs the count value. Reference numeral 43 is a comparator, which compares the line value output from the central processing unit with the coefficient value output from the scanning line counter and outputs a write enable signal in the same case. The write enable signal is a negative pulse signal.

51 is an analog switch, which is automatically switched according to the signal output from the comparator. 52 is a television monitor, which outputs a video signal.

Hereinafter, the operation and effect according to the present invention will be described in detail.

2 and 3, the input / output border 21 outputs a video signal input to a TV, a video tape recorder, a camera, or the like to the central processing unit 34 one frame (one lower surface). .

In addition, the delay line 31 delays the line signal of the composite video signal by one horizontal scanning time and outputs it to the A / D converter 32. In the A / D converter 32, the line signal output from the delay line 31 is sampled at 100 MHz and converted into a digital signal.

On the other hand, in the sync separation circuit 41, the horizontal sync signal HD and the vertical sync signal VD included in the composite video signal are separated and output to the scan line counter 42. At this time, the scan line counter 42 continuously counts and outputs the horizontal scan line inputted from the synchronous separation circuit unit 41 from 1 to 525 (scan line in the NTSC method), and resets the vertical sync signal when the vertical sync signal is inputted to the clear terminal (CLR). The counting for the horizontal scan line corresponding to one frame is terminated, and the scan line corresponding to the next frame is counted.

If the SECAM or PAL method has 625 scan lines, the scan line counter 42 counts from 1 to 625 if the present invention is applied to the SECAM or PAL method.

When the central processing unit 34 selects an arbitrary horizontal line for analysis on the still image displayed on the monitor using the key board 34, the central processing unit 34 selects a line value corresponding to the horizontal line. The comparator 43 compares the count value output from the scan line counter 42 and the selection line value output from the central processing unit 34 to output a negative pulse signal in the same case.

For example, if the user selects the 10th horizontal scan line with the keyboard 34 to analyze the image signal corresponding to the 10th horizontal scan line on the monitor by looking at the computer monitor 35, the central processing unit 34 receives the 10th horizontal scan line. The signal corresponding to the output signal is input to the one input terminal of the comparator 43. In this case, the frequency counter 42 counts a horizontal scan line, and when the count value corresponding to 10 corresponds to 10, the comparator 43 outputs a negative pulse signal.

The negative pulse signal output from the comparator 43 stores the digital signal converted by the A / D converter 32 at the instant of being provided as a write enable signal to the memory 33, and further includes the negative ( When a pulse signal is output, a display line is generated on the horizontal scan line to be analyzed on the screen which is instantly switched by the analog switch 51 and appears on the television monitor 52.

According to the present invention as described above, an image line signal is processed at a high sampling rate of 100 MHz and stored in a memory, a still image is displayed on a monitor, and an image to be analyzed is selected on the screen. It is an excellent effect to analyze the waveform of the selected line signal of the video screen while viewing directly on the screen.

Claims (1)

An input / output border 21 for receiving a composite video signal and outputting the composite image signal to the central processing unit one frame at a time; A delay line 31 for delaying the line signal of the composite video signal by one horizontal scanning time and outputting the delayed signal; An A / D converter 32 for converting the output signal of the delay line 31 into a digital signal; A memory 33 for storing the output signal of the A / D converter 32 when a write enable signal is input; The video signal of one frame and the output signal of the memory are processed and output to the monitor, and an arbitrary horizontal line is selected for analysis on the still image displayed on the monitor. A central processing unit 34 for outputting a line value corresponding to a line; A monitor (35) for displaying a screen and a line waveform output from the central processing unit (34); A synchronization separator circuit 41 for separating a horizontal synchronization signal and a vertical synchronization signal of the double image signal; A scan line counter 42 for counting a horizontal scan line using the horizontal sync signal of the sync separating circuit section 41 and outputting the count value; And a comparator 43 for comparing a line value output from the central processing unit 34 and a count value output from the scanning line counter 42 and outputting a write enable signal when they are identical to each other. Signal waveform analysis device.