JPH0752968B2 - Video signal waveform display device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for displaying a signal waveform of a video signal on the screen of a television receiver.

2. Description of the Related Art In recent years, television devices have become widespread as television broadcast receivers and computer displays, but in addition to such original display of images and characters, various visual appealing displays are possible. is there. For example, the waveform display device previously proposed by the present applicant in Japanese Patent Application No. 1-223567 can display a received video signal as a time-series waveform like an oscilloscope. It is noteworthy that it can display a larger screen than the oscilloscope as an additional function of.

Hereinafter, a conventional waveform display device will be described with reference to the drawings.

FIG. 9 is a block diagram showing the configuration of a conventional video signal waveform display device.

In FIG. 9, 1 is an input terminal, 2 is an amplifier for amplifying the input video signal to a predetermined level, 3 is an A / D converter for converting the video signal into a digital value, and 4 is the A / D converted video signal. A memory for storing a waveform for one horizontal section, 5 is an address counter for generating an address AD when storing or reading in the memory, 6 is a line counter for counting lines for waveform display, 7 is a comparator, The data from the memory 4 is compared with the output of the line counter 6, and when the two values match, the output is turned on. A scale generator 8 generates a scale signal corresponding to the scale of the oscilloscope. A mixer 9 mixes the waveform signal, the scale signal and the synchronizing signal and outputs a display output signal to the output terminal 10. A sync signal separator 11 separates a horizontal sync signal and a vertical sync signal from the input video signal. A control unit 12 generates a signal for controlling the operation timing of each unit and outputs a synchronization signal to a terminal 14. A clock generator 13 generates a clock signal CK necessary for each block.

The operation of the conventional video signal waveform display device configured as described above will be described below.

First, the input video signal input to the input terminal 1 is input to the amplifier 2
Is amplified to a predetermined size by the A / D converter 3 and analog-digital converted (A / D converted).

This waveform is displayed by the control unit 12 when the input signal is interlaced as in the NTSC system, the field is discriminated, and the write signal WR is generated in the memory at the desired horizontal scanning to display the waveform. Only the line (one horizontal section) is selected and stored in the memory 4.

The memory data is repeatedly read for each horizontal section by designating the address AD by the address counter 5.

On the other hand, the line counter 6 is a down counter, which is preset to a maximum value of 255 by the vertical synchronizing signal VP and decremented by 1 every 1H (1 scan). The comparator 7 receives the data V read from the memory representing the voltage level and 1H
The value of the output L of the line counter 6 that decreases each time is compared, and a signal voltage is generated at the output terminal only at the point where V and L match, and this becomes the waveform signal of the image. At the same time, a scale signal is generated by the scale generator 8 and a synchronization signal SYNC synchronized with this waveform output signal is output from the control unit 12.
Is output to terminal 14. The waveform signal, the scale signal, and the synchronization signal SYNC are mixed by the mixer 9 to be converted into a composite video signal (television signal) and output to the output terminal 10.

In this way, the video signal is stored in the memory for the signal in one horizontal section, read out in accordance with the horizontal scanning of the television receiver, and the waveform signal is obtained by comparing it with the value of the line counter synchronized with the vertical scanning. The waveform can be displayed on the screen of the television receiver like an oscilloscope.

As a concrete example, if the scanning line shown in the figure is displayed in a waveform on a screen on which the Japanese flag is displayed as in the screen in FIG. 10a, the waveform display as in FIG. 10b can be obtained. become.
In this waveform display, is a horizontal synchronizing signal, is a color burst reference signal, and is a color carrier and corresponds to the red of the Japanese flag. The broken line is the scale, the horizontal axis is time, and the display period is about
It is 1H. The vertical axis is voltage, and the unit is scaled by IRE display.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The above-mentioned waveform display device realizes the function of an oscilloscope on a television screen, and makes it possible for general people who do not have an oscilloscope to see the waveform of the signal, and a new television receiver is provided. It is valuable as a function.

However, in the above configuration, the oscilloscope function is simply realized on the TV screen, so when evaluated as an additional function of the TV receiver, what the displayed waveform shows as a general person who is not an expert can see. It had a problem that it was difficult to tell if it was there.

Therefore, the development of a waveform display device that displays the video signal in a waveform that is easy to understand has been desired.

The present invention has been made in view of the above problems, and it is possible to display the waveform of the video signal in an easy-to-understand manner by separately coloring the waveform of the video signal into the image signal of the chroma portion and the non-chroma portion and the synchronization signal. The present invention provides a video signal waveform display device that can be used.

In order to achieve this object, a video signal waveform display device of the present invention comprises a chrominance carrier signal detector, an A / D converter, and (Y +
C) and (Y-C) computing units, memory, means for selecting horizontal scanning lines to be stored in the memory, memory address counter, line counter, (Y + C) signal, and (Y-
C) It is provided with a comparator for comparing the magnitude of the signal, the value of the line counter and the reference value.

According to the present invention, with the above-described configuration, the reference level is set to the pedestal, and the portion surrounded by the reference level and the synchronizing signal and the portion surrounded by the reference level and the (Y-C) video signal of the image section are colored. At the same time, (Y + C) signal and (Y-C)
By painting the portion surrounded by signals as a chroma signal in another color, the video signal waveform can be divided into a sync signal, a luminance signal, and a chroma signal for easy display.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a video signal waveform display device according to an embodiment of the present invention. In FIG. 1, 1
Is an input terminal, 5 is an address counter, 6 is a line counter, 8 is a scale generator, 11 is a sync separator, 12 is a control unit, 13 is a clock generator, and 14 is a sync signal output terminal. It has the same function as that of the same reference numeral in the configuration of the conventional example shown in the figure, and the same reference numeral is given and its detailed description is omitted. 23 is a composite color video signal and a luminance signal Y
And a color sub-carrier C are separated by Y / C separator 22, 22 is a chroma detector for peak-detecting the separated color sub-carrier C to obtain a chroma signal C, and 23 is a low-pass filter for cutting harmful high frequency components. At the same time, the chroma detector 22 delays the luminance signal Y by an amount of time the chroma signal is delayed. Reference numerals 24 and 25 denote adders and subtractors, respectively, which calculate (Y + C) and (Y-C) from the luminance signal Y and the detected chroma signal C. 3a and 3b
Are A / D converters for converting the (Y + C) signal and the (Y-C) signal into digital values, and 4a and 4b are horizontal lines of the A / D-converted (Y + C) signal and the (Y-C) signal. A memory for storing waveforms for a period, 7 is a magnitude comparator, which compares the data from the memories 4a and 4b with the magnitude of the output of the line counter 13,
A waveform signal corresponding to the magnitude relationship of the respective signals is output, and a specific configuration is shown in FIG.

In the figure, 71, 72 and 73 are 8-bit digital comparators, and the output becomes true when the A input is larger than the B input. 74 and
77 is an AND circuit, 75 is an exclusive OR circuit, and 76 is an inverter.

Fig.1 26a, 26b and 26c are circuits for setting color of non-chroma, chroma and scale respectively, and 9R, 9G and 9B mix these signals to obtain red, blue and green signals respectively. The RGB waveform signals obtained by the mixer are R, G, and B respectively.
Is output to the output terminals 10R, 10G, 10B.

The operation of the video signal waveform display device configured as described above will be described below with reference to FIGS. 1 and 3. FIG. 3 shows the waveform of each part when the video signal of FIG. 10b is input.

First, the input composite video signal of FIG. 10b is the Y / C separator 2
The luminance signal Y and the color subcarrier signal C are separated by 1 and become as shown in FIGS. This color subcarrier signal C is peak-detected by the chroma detector 22 and the chroma signal C representing its amplitude is obtained as shown in FIG. On the other hand, the luminance signal Y is time-adjusted through the delay circuit 23, and then is added to and subtracted from the chroma signal C by the adder 24 and the subtractor 25, and the (Y + C) signal of FIG. Y-
C) Obtain the signal. The (Y + C) signal and the (Y-C) signal are converted into 8-bit digital values by the A / D converters 3a and 3b, respectively, and then one horizontal scanning line is selected by the control unit 12 to store them in the memory respectively. It is stored in 4a and 4b. This memory data is repeatedly read for each horizontal section by designating the address AD by the address counter 5, and is input to the magnitude comparator 7.

The line counter 6 is a down counter that is decremented by 1 every 1H (one scan) as in the conventional example, and its output is also input to the magnitude comparator 7.

The magnitude comparator 7 of the present invention does not output only coincidence like the comparator of the conventional example, but detects a chroma portion and a non-chroma portion based on the magnitude relation of a plurality of input values. The operation will be described with reference to.

Input signal is the data (Y + C) read from the memory
And a (Y-C), the output value L of the line counter 6, the reference value L _O from four 8-bit digital value data addition, comparison of these large and small, as follows.

First, when the line counter output L is between (Y + C) and (Y-C), that is, (Y + C)>L> (Y-C) (1), the inputs of the comparison circuit 71 and the comparison circuit 72 are both A. > B, and A> B outputs are both true. Therefore, the output of the AND circuit 74 becomes true and the chroma part output is turned on, and this becomes a chroma part waveform signal.

On the other hand, when the value of the line counter is upper i.e. L> L _O from the reference line is the true output of the comparator circuit 73 is L <output (Y-C) comparing circuit 72 when becomes false exclusive OR circuit 75 Output is true. On the other hand, when it is below the reference line, that is, when L <L _O , the output of the comparison circuit 73 is false. Therefore, when L> (Y−C), the output of the comparison circuit 72 becomes true and the output of the exclusive OR circuit 75 becomes true. Becomes Since the output of the exclusive OR circuit 75 is masked by the gate of the AND circuit for the above chroma output part, eventually L> L _O and L <(Y−C) (2) or L <L _O and L> ( Y + C) When (3), it is output as a non-chroma part.

Apply this to the actual waveform. The waveform in Fig. 3 is a superposition of the waveforms of D and E for clarity. In the waveform diagram (f), when the line counter is L = La, the above condition is not satisfied. When scanning L = Lb, point a has no output, point b has non-chroma output because it satisfies the condition (2) above, and point c has chroma output because the condition (1) is satisfied. When scanning L = Lc, d
Since the point satisfies the condition of (3), it becomes non-chroma output, and e
The point has no output, and the point (f) satisfies the condition (1), so that it is a chroma output.

The chroma part waveform signal and the non-chroma part waveform signal obtained in this manner are combined with the scale signal from the scale signal generator 26c together with the color setter color selectors 26a, 26b, 26, respectively.
The color to be displayed is determined by c and mixed by the RGB mixers 9R, 9G and 9B. The RGB signals thus created are output from the output terminals 10R, 10G, and 10B, respectively, and when reproduced on the screen of the display, they become as shown in FIG. In this case, the chroma part is magenta and the non-chroma part is white.

The non-chroma part waveform signal represents the luminance signal above the reference line and the sync signal below.

As described above, according to this embodiment, the Y / C separator for separating the luminance signal and the chroma signal, the chroma signal detector converter (Y
+ C), (Y-C) calculator, (Y + C) calculator and (Y
-C) By providing the configuration of the arithmetic unit and the magnitude comparator of the value of the line counter, the setup of the video signal and the (Y-C) signal value are colored with the setup and the synchronization signal, and the chroma signal is lit. By applying a different color on the signal, the sync signal, the luminance signal, and the chroma signal can be distinguished, and an easy-to-see display can be made.

In the above example, the signal portion of the non-chroma portion and the synchronizing signal portion have the same color, but they may have different colors.

Another embodiment of the present invention will be described below with reference to the drawings.

4, 5 and 6 are block diagrams showing another embodiment of the present invention.

These figures show only the portion corresponding to the portion surrounded by the broken line in the configuration of FIG. 1, and the other parts are exactly the same as FIG. 1, and the overall function is not particularly different from that of FIG. .

In the example of FIG. 4, the luminance signal Y and the detected chroma signal C are A /
After D conversion and reading from memory, (Y + C) and (Y-C) operations are performed with digital signals.

In the example of FIG. 5, the luminance signal Y and the chroma signal C are A / D converted, read out from the memory, and then the detection of the chroma signal and the operations (Y + C) and (Y-C) are performed by digital signals.

In the example of FIG. 6, the input composite signal V is A / D-converted, read from the memory, and then Y / C separation, chroma signal detection, and (Y + C) and (Y-C) calculations are performed using digital signals. ing.

FIG. 7 is a block diagram showing the configuration of another embodiment of the present invention.

In FIG. 7, reference numeral 22 denotes a chroma demodulator which outputs a color difference signal (RY) signal and (BY) signal from the color subcarrier C, which are converted into digital values by A / D converters 3b and 3c, respectively. Input to memories 4b and 4c. The multiplier 31 uses the color difference signal (R-
Y) signal and (BY) signal are multiplied to obtain the absolute value thereof, and the detection value C of the chroma signal in the embodiment of FIG. 1 is obtained.
You get the same thing as. Reference numerals 32a, 32b and 32c are D / A converters for converting the luminance signal Y, the color difference signal (RY) signal and the (BY) signal read from the memory into analog signals. A matrix circuit 33 synthesizes primary color signals R, G and B from these signals. This RGB signal is supplied to the chroma section color setting circuit 26a to determine the color of the chroma section. The RGB signal is also supplied to the switching circuit 34, switched to a waveform signal according to an instruction from the control unit 12, and output to the output terminals 10R, 10G, 10B. The configuration other than the above is the same as that of FIG. 1, and the description thereof is omitted.

Next, the operation will be described.

The color subcarrier C separated from the input composite signal V by Y / C is supplied by the chroma demodulator 22 to a color difference signal (RY) signal and (B−).
Y) The signal is demodulated and then converted into digital values by the A / D converters 4b and 4C and stored in the memory. The (RY) signal and the (BY) signal read from the memory are multiplied by the multiplier 31 to obtain the absolute value, and the same value as the chroma detection signal C in FIG. 1 is obtained. The output of the chroma part and the non-chroma part by the comparator 7 is the same as in FIG.
On the other hand, the luminance signal Y and the color difference signal (R-
The (Y) signal and the (BY) signal are D / A converters 32a, 32b, 3
It is converted into an analog signal by 2c, and the primary color signals R, G, B are further combined by the matrix circuit 33. This means that the one-line video signal stored in the memory is reproduced as it is. The reproduced color signal is supplied to the chroma section color setting circuit to set the color of the chroma section. On the other hand, this primary color signal
The R, G, B signals can be directly output by the switching circuit 34. In this case, the content of one horizontal scanning line extracted from the input signal is repeatedly output to the entire screen on all horizontal scanning lines of display output. It will be.

As a result, the color burst signal and multi-burst signal inserted in the vertical blanking period can be viewed on the full screen, which is useful for checking the display device.

FIG. 8 is a block diagram showing an example of the configuration of a video signal generating device focusing only on this function. The unnecessary components are deleted from the configuration of FIG. 7 and converted into a composite video signal (television signal) by the encoder 35. Then, the output signal is obtained.

In the examples given so far, the input is the composite signal V and the Y / C separation is performed, but of course, the component Y signal and C signal may be input.

Although the waveform display output is RGB output, it may be encoded into a composite video signal of NTSC or another system and output.

Further, the period of the line for taking in the input signal has been described as 1H, but it can be 1H or less or several H.

EFFECTS OF THE INVENTION As described above, the present invention provides a chroma signal detector and (Y +
C), (Y-C) arithmetic unit, A / D converter, memory, line counter and magnitude comparator are provided to divide the video signal into a chroma portion and a non-chroma portion, and a non-chroma portion is further divided. By separating the setup and the signal value and the setup and the synchronization signal and dividing each part into different colors, it is possible to easily distinguish the synchronization signal, the luminance signal, and the chroma signal, and it is possible to provide an easy-to-understand display. Further, it is possible to generate a video signal for displaying the reference signal inserted in the vertical blanking period on the entire screen, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a video signal waveform display device in a first embodiment of the present invention, FIG. 2 is a circuit diagram showing a configuration of a main part of FIG. 1, and FIG. 3 is a diagram showing the present invention. Waveform diagrams for explanation, FIG. 4, FIG. 5, and FIG.
FIG. 7 is a block diagram showing a part of the configuration example of the video signal waveform display device in each of the third and fourth embodiments, and FIG.
FIG. 8 is a block diagram showing a part of a configuration example of a video signal waveform display device in the embodiment of the present invention, FIG. 8 is a sixth embodiment of the present invention, and is a configuration of the video signal generation device in which the embodiment of FIG. FIG. 9 is a block diagram showing the configuration of a conventional video signal waveform display device, and FIG. 10 is a waveform diagram for explaining its operation. 21 ... Y / C separator, 22 ... Detector, 24 ... Adder, 25 ...
… Subtractor, 3a, 3b …… A / D converter, 4a, 4b …… Memory, 7
…… Large and small comparators.

Claims (2)

[Claims] 1. A means for obtaining a signal C obtained by detecting a color carrier signal of a composite color video signal, and a luminance signal Y and a color detection signal C to (Y + C) and (Y-C).
A means for calculating the (Y + C) and (Y−C) analog signals, A / D conversion means, a memory for storing the waveform of the digitally converted signal for a certain period, and a horizontal memory for storing in this memory. A means for selecting a scanning line, a line counter for counting the horizontal scanning lines of the output video signal to be displayed in waveform, a means for comparing the data of (Y + C) and (Y-C) with a reference value and the value of the line counter. The composite color video signal is divided into a chroma portion and a non-chroma portion, and the non-chroma portion is further divided between a setup and a signal value and a setup and a synchronization signal, and at least a part of them is displayed as a predetermined color component. A video signal waveform display device characterized by being configured as follows. 2. A means for demodulating a color signal, and a means for storing the color information of an input video signal in a memory as well, based on at least one of a hue and a color density read from the memory and demodulated. 2. The video signal waveform display device according to claim 1, wherein the chroma portion of the waveform display output signal is displayed as a predetermined color component.