JPH0350988A - System converter - Google Patents

Abstract

PURPOSE:To display a signal onto a receiver of the current 525-line system with an aspect ratio of 16:9 by providing a circuit thinning 3 scanning lines of a MUSE signal into one and a circuit converting the time axis of the MUSE signal into the 525-line system. CONSTITUTION:A video signal of a MUSE signal comes to an input terminal 1 and a pre-filter 2 eliminates the distortion caused by thinning the scanning line number into 1/3. Then the time axis of 375-line of luminance signal interleaved into 1/3 by an extraction circuit 4 is converted into the scanning of 525-line system from the MUSE scanning at a luminance scanning line conversion circuit. On the other hand, a color decode circuit 3 decodes two synchronous color signals, the extraction circuit 5 extracts one from 3 lines and a color scanning conversion circuit 7 applies time axis conversion from the MUSE scanning into the scanning of 525-line system. The luminance signal converted into the 525 line system and two color signals are given via a D/A converter 8, and a luminance signal whose aspect ratio is 16:9 is obtained at an output terminal 9 and the color signals whose aspect ratio is 16:9 are obtained at output terminals 10, 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention converts the MUSE signal with an aspect ratio of 1G=9, which has been proposed as a high-visibility broadcasting system, from the current 525
This invention relates to a device that converts the format so that it can be viewed on a television receiver of this format.

Conventional technologyThe EMUSE method was proposed as a method for compressing and transmitting wideband video signals such as high-vigilance signals.
NHK Technical Research (Development of MUsE method) No. 398 No. 2 (1986).

A system conversion device for viewing MUSE signals on current television receivers has also been proposed. The detailed salt For example [Mυ5E-
525 Converter J (363 Institute of Electronics, Information and Communication Engineers Spring National Conference D-169). In the embodiment of the conversion method described in this article, the wide aspect ratio is achieved by cutting off both sides of the wide screen of a high-visibility screen.
This is intended to display images on both sides of the 4:3 aspect ratio of current television receivers. The number of scanning lines is converted from 1125 to 1050, and then to 525.

Problems to be Solved by the Invention However, there is a problem in that the format conversion device as described above can only display a signal by cutting off both sides of the signal sent.

The present invention solves this problem! Book MυSE with aspect ratio 16:9 sent without cutting off both sides
An object of the present invention is to provide a format conversion device that can display a signal on a current 525 format television receiver with the same aspect ratio.

Means for Solving the Problems The present invention includes a prefilter that eliminates distortion caused by thinning out to 525 lines, a circuit that thins out the three scanning lines of the MUSE signal to one, and a time axis changer from the MUSB signal to 525 lines. This system conversion device includes a conversion circuit and a circuit that converts two color signals sent line-sequentially into simultaneous signals.

Effect of the present invention With the above-described configuration, a MUSB signal with a number of scanning lines of 1125 is thinned out to 375 lines using a 1/3 thinning circuit, and the time axis is converted to a 525 line system using a time axis conversion circuit. The aim is to display the MtJSR signal at an aspect ratio of 16:9.

Example Embodiments of the present invention will be described below with reference to the drawings.

Regarding the signal format of the MUSE signal, refer to the above document "MυSE
The two color signals R-Y are described in detail in
, B-Y signal is time-axis compressed to 1/4 and is transmitted line-sequentially and time-axis multiplexed with the luminance signal. Furthermore, the chrominance signal is transmitted 4 horizontal scanning periods (4H) ahead of the luminance signal. Explain as if there is no such thing.

Number of scanning lines: 525 East Aspect ratio: 4:3 (16:12)
Aspect ratio for current receivers! To display a 6:9 signal, it is sufficient to display it with the number of scanning lines of 525X9+12-394. However, to convert from 1125 to 394 scanning lines, the number of scanning lines must be reduced to 1/2.855. There is. Therefore, for ease of implementation, the present invention thins out the number of scanning lines to 375, which is 1/3 of the simple ratio, as shown in FIG.
The aim is to display images with an aspect ratio of 16:9 on the display section of current television receivers.

FIG. 1 is a block diagram of a system conversion device according to an embodiment of the present invention. In Figure 1, 1 is the input, 2 is a prefilter that removes distortion that occurs when thinning the signal to 1/3,
3 is a color decoding circuit that restores color signals transmitted line-sequentially into two types of simultaneous color signals; 4 and 5 are sampling circuits that extract every second signal; and 6 is a luminance circuit that performs time axis conversion of luminance signals. 7 is a color scanning conversion circuit that performs time axis conversion of color signals; 8 is a D/A converter that converts digital signals into analog signals; 9 is a luminance signal output 10, 11
is the color signal output terminal.

In the format conversion device of this embodiment configured as described above, the method of thinning out the scanning lines to 1/3 is as shown in FIG. Select every other book! / Thin out to 3, color signal (C+, Cz, C3
) converts the gold signals transmitted line-sequentially into simultaneous signals, and then converts each color signal into two signals in the same way as the luminance signal.
It selects every other book and thins it down to 1/3.

It is assumed that odd numbers in the subscripts of color signals represent RY signals, and even numbers represent BY signals.

Next, its operation will be explained. An A/D converter (
A video signal of the MυSE signal, which has been converted into a digital signal by a converter (not shown), arrives. Prefilter 2 increases the number of scanning lines to 17
Distortion caused by thinning out to 3 is removed. Of the video signals from which distortion has been removed, the time-axis multiplexed luminance signal Y is extracted and sent to rgJji4.
, Y4. Y7... every second one is pulled out.

The 375 luminance signals thinned out to 1/3 are converted from MUSH scanning into 5 luminance signals by a luminance scanning conversion circuit 6 composed of memory elements.
The time axis is converted into a 25-way scan. The IX degree scan conversion circuit 6 performs horizontal time axis conversion to convert one horizontal scanning time of the MυSE signal into one horizontal scanning time of the 525-line method, and also converts the screen with 375 scanning lines as shown in Figure 3. In order to configure this, a vertical continuous read conversion is performed in which continuous reading is performed at appropriate times in the vertical period.

The line-sequential time axis multiplexed color signal is processed by the color decoding circuit 3.
restored to two simultaneous signals. As mentioned above, the color signals of MUSH are two color difference signals RY.

B-Y are sent alternately. If you extract every second color signal in the same way as the luminance signal, you will be able to restore only one of the color signals.Therefore, in the present invention, as shown in Fig. 4, we will restore the color signal using all the color signals sent. That is. Now, if Y4 is extracted as a luminance signal, the B-Y signal is C which is sent on the same scanning line.
4, the RY signal is C1 sent by the front and rear scanning lines,
This is an attempt to restore using the average of Cs.

As shown in FIG. 5, the color decoding circuit 3 includes one horizontal scanning period (IH) delay circuits 71 and 72, an addition circuit 573,
It consists of a 172 circuit 74 that reduces the signal size by half and a switching lever 175. The signal (OH) arriving at the terminal 70 is sent to the IH delay circuit 71 where only the color signal is subjected to an IH delay (IH delay circuit 71).
H) The LIH delay circuit 72 further delays IH (2H
) to be made to do.

The adder circuit 73 adds the OH signal and the 2H signal, l/2
When the magnitude of the signal is halved by the circuit 74, the averaged R-Y signal and the B-Y signal are alternately obtained on the line 78. IH! On the output line 79 of the extension circuit 71, opposite BY signals and RY signals are obtained alternately. When the switching circuit 75 switches between the connection shown by the solid line and the connection shown by the dotted line for each IH, the R-Y signal is applied to the terminal 76 (the B-Y signal is continuously obtained to the terminal 77). is restored.

The color signals restored to the two simultaneous signals are extracted from each three signals into one signal by a sampling circuit 5 and sent to a color scanning conversion circuit 7 composed of a memory element. The color signals of the two types of layers, each having 375 lines thinned out to 1/3, are time-axis converted from MUSH scanning to 525-line scanning in the color scan conversion circuit 7.The 0 color signal is time-axis multiplexed. Since the time axis is compressed to 174, horizontal time axis conversion is performed and
The time axis compressed to 1/4 is also expanded and read out. Further, similar to the luminance signal, vertical continuous a readout conversion is also performed.

The luminance signal and two color signals converted to D.525 format are D/
The A converter 6 converts the digital signal into an analog signal, and the output terminal 49 converts it into a 525-line system.
As explained above, according to this embodiment, the transmitted MUS with an aspect ratio of 16:9
The E signal can be displayed on the current 525-line receiver with the aspect ratio of 16+9, and since the color signal is restored using all the signals sent, high-quality images can be displayed.

FIG. 2 shows a system converter according to a second embodiment of the present invention. In the figure, the same numbers are given to the parts that operate in the same way as in FIG. 1, and the explanation thereof will be omitted. 21 is the luminance signal l/3
22 is a vertical readout circuit that performs time axis conversion from MUSE scanning to 525-line scanning.
! 23 is a color expansion circuit WK for restoring the color signal compressed to 1/4 on the time axis to the original time axis for time axis multiplexing; and 24 is a scan conversion circuit.

The operation of the format conversion device of the second embodiment configured as described above will be described below. In the luminance thinning circuit 21 composed of a memory element, luminance signals are written every second luminance signal, horizontal time axis conversion is performed from MUSB scanning to 525 scanning, and the signals are read out. The luminance signal subjected to the horizontal time axis conversion is subjected to vertical continuous readout conversion in the vertical readout conversion circuit 22.

The color expansion circuit 23 is constituted by a memory element, and the time-axis multiplexed color signal is read in, expanded four times in the time axis, and read out. The color signal expanded four times along the time and M axes is converted from a line-sequential signal into two simultaneous color signals by a color decoding circuit 5. A sampling circuit 6 extracts every second color signal from each color signal. The extracted two color signals are subjected to horizontal time axis conversion from MUSH scanning to 525-line scanning in the scan conversion circuit 24, and vertical continuous readout conversion.

As described above, according to this embodiment, by configuring the luminance amount JI 21 with a memory element and providing the color expansion circuit 23 before the color decoding circuit 5, it is possible to reduce the operating speed of the subsequent circuit. In addition to stabilizing the operation, it can be constructed using low-speed and inexpensive elements.

FIG. 6 is a block diagram of a system conversion device according to a third embodiment of the present invention. In Figure 6, 33 is 1 horizontal I
AM (I H) MMMB234+! Y, which simultaneously extracts every second luminance signal and color signal of the MIJSE signal;
C extraction circuit, 35 extracts only the color signal of the MLISR signal.
The number of times C sampling is performed every other book 36 is a color decoding SW1 that rearranges the color signals that are alternately transmitted line-sequentially into two types of continuous color signals.

In the system conversion device of this embodiment configured as described above, the luminance signals (Y +, Y a, Y to,
This is to select J, color signals (C+, Ca, Ct...), and color signals (C2, Cs, Cm...) of the next scanning line.

The operation will be explained below. A video signal of the MUSE signal, which has been converted into a digital signal by an A/D converter (not shown), arrives at the input end 1 . Increase the number of scanning lines with prefilter 2!
The distortion caused by thinning out to /3 is removed. One of the output signals of the prefilter 2 (FIG. 8a) is sent to the IH delay circuit 33, and the other to the C sampling circuit 35. I
The signal (b) delayed by one horizontal period by the H delay circuit 33 is y,
The C sampling circuit 34 extracts every second luminance signal and color signal together (C), and at the same time, the C sampling circuit 35 extracts only the color signal from every second signal (d).

The luminance signals thinned out to 1/3 by the Y and C sampling circuit 34 are converted into MUS by the luminance scanning conversion circuit 6 composed of memory elements.
The time axis R is converted from H scanning to 525 line scanning. The brightness scanning IV4 circuit 6 performs horizontal time axis conversion to convert one horizontal scanning time of the MUSE signal into one horizontal scanning time of 525 lines, and also converts the west face with 375 scanning lines as shown in Figure 3. For this purpose, a vertical continuous read conversion is performed in which continuous reading is performed at appropriate times in the vertical period.

As described above, the MUSH color signals are two color difference signals R-Y and B-Y that are sent alternately. Therefore, if you extract every second line, you will only get one color signal, that is, line 13 has R-Y, B-Y,
R-Y... signal power (line 14 has the opposite B-Y,
Signals of RY, B-Y, . . . are obtained.

Therefore, when the switch of the 8-color decoding circuit 36 that performs rearrangement using the color decoding SW 36 is switched between the position shown by the solid line and the position shown by the dotted line at a 3H cycle, the line! A continuous color difference signal RY is obtained on the line 16 (a continuous color difference signal B-Y is obtained on the line 16).

Color signal restored into two continuous color difference signals by color decoding 5W36 Color scan conversion circuit 7 composed of memory elements
The 0 color signal, which is time-axis converted from MUsE scanning to 525-line scanning, is sent to 1 to perform time-axis multiplexing.
Since the time axis is compressed to 1/4, horizontal time axis conversion is performed, and the time axis compressed to 1/4 is also expanded and read out. Further, similar to the luminance signal, vertical continuous readout conversion is also performed.

The luminance signal and two color signals converted to D.525 format are D/
The A converter 8 converts the digital signal into an analog signal, and the output terminal 9 converts it into a 525-line system.
When converted to this method, two types of color signals with an aspect ratio of 16:9 can be obtained.The IH delay circuit 33 placed before the Y and C sampling circuits 34 in FIG. 6 is placed before the C sampling circuit 35. However, it is clear that the same effect as this embodiment can be obtained by simply using the color signal of the previous scanning line from which the luminance signal has been extracted.

As explained above, according to this embodiment, among the two color signals, one is the color signal of the same scanning line as the extracted luminance signal, and the other is the color signal of the same line or the next scanning line. is used. As a result, the spatial distance between the luminance signal and the color signal is short (and a high-quality image can be obtained).

As described in detail, according to the present invention, a transmitted MUSE signal with an aspect ratio of 16:9 is converted into an aspect ratio of 6:9.
:9 can be displayed on the current 525-line system receiver, and its practical effects are great.

[Brief explanation of drawings]

FIG. 1 shows the blocks of a format conversion device according to one embodiment of the present invention. FIG. 2 shows the blocks of a format conversion device according to another embodiment of the present invention. FIG. 3 explains the display method. FIG. 5 is a block diagram of a color decoding circuit, and FIG. 6 is a block diagram of a system conversion device according to another embodiment of the present invention. FIG. 7 is a block diagram of a signal thinning method. FIG. 8 is an explanatory diagram of the extraction operation. 1. Input line 2. Prefilter, 3. Color decoding circuit, 4, 5. Sampling circuit, 6. Luminance scan conversion circuit, 7. Color scan conversion circuit 8. -D/A strange v! 1 drop
9... Luminance signal output a 10, 11... Color signal output salt 21... Luminance thinning circuit, 22... Vertical readout conversion circuit 2
3...Color expansion circuit, 24...Scan conversion circuit, 71.72
...IH delay circuit, 73...addition circuit, 74...1
/2 circuit, 75...switching circuit, 33...1 horizontal scanning period delay circuit, 34...Y, C sampling circuit, 35...C
Sampling circuit, 36...color decoding SW. Agent's name: Patent attorney Shigetaka Awano Name No. 373 1 Otsuchi Figure L] Industry 7 Figure HU, SE type signal 9 Collar, 52S tree system

Claims (3)

[Claims] (1) A pre-filter to remove distortion caused by thinning out the number of scanning lines to 1/3, a sampling circuit to thin out the luminance signal to 1/3, and a color signal transmitted line-sequentially to two simultaneous colors. A color decoding circuit that restores the color signal to a signal, a sampling circuit that thins out the restored color signal to 1/3, a brightness scan conversion circuit that converts the time axis of the brightness signal from the MUSE signal format to the 525 signal format, and a color signal that converts the color signal to the MUSE signal. A format conversion device comprising: a color scanning conversion circuit that converts the time axis from a format to a 525-line format; (2) A prefilter for removing distortion caused by thinning out the number of scanning lines to 1/3, a luminance thinning circuit that thins out the luminance signal to 1/3 composed of memory elements, and a luminance thinning circuit that thins out the luminance signal to 1/3, and A vertical readout conversion circuit that performs vertical continuous readout conversion, a color expansion circuit that expands the time axis of a color signal by four times, and a color decoding circuit that restores a color signal transmitted line-sequentially into two simultaneous color signals. A format conversion device comprising: a sampling circuit that thins out a restored color signal to 1/3; and a scan conversion circuit that converts the time axis of the color signal into a 525-line format. (3) A pre-filter for removing distortion caused by thinning out the number of scanning lines to 1/3, a one-horizontal scanning period delay circuit, and a Y. A C extraction circuit extracts only color signals, a color decoding SW rearranges color signals that are alternately transmitted line-sequentially into two types of continuous color signals, and converts luminance signals from MUSE signal format into 525. A format conversion device comprising: a luminance scan conversion circuit that converts a time axis to this format; and a color scan conversion circuit that converts a color signal from a MUSE signal format to a 525-line format.