KR970003433B1 - Television receiver for moniterace scanning - Google Patents

Abstract

The non-interlaced scanning type of a television receiver has a motion adaptive type to prevent the deterioration of image generated due to still image. The non-interlaced scanning type of the television receiver comprises: a motion detector(31) whether a luminance signal(Y) of the image signal defected is still image or motional image; an arithmetic average means(32) for selectively performing an arithmetic averaging for the luminance signal(Y) in accordance with the detected result of the motion detector(31) upon interpolating scanning; and a non-interlaced scanning converter for interlaced-converting a chrominance signal(C).

Description

TV-type television receiver

1 is a view for explaining the problem of the conventional scanning method.

2 is a block diagram showing the configuration of a television receiver according to the prior art.

3 is a block diagram showing the configuration of a scanning television television receiver according to an embodiment of the present invention.

FIG. 4 is a block diagram showing in detail the configuration of a motion detection circuit and an arithmetic mean circuit in FIG.

FIG. 5 is a diagram showing output signals of circuit parts in FIG.

* Explanation of symbols for main parts of the drawings

1: antenna 2: tuner

3: image intermediate frequency circuit 4: image detection circuit

5: Y / C separation circuit 10: Image matrix circuit

32: Arithmetic Mean Circuit 33: Color Demodulation Circuit

34: Multiplexer 35: Injector Converter

36: demultiplexer 41, 42: line memory

43: adder 44: division circuit

45: field memory 46: subtractor

47: comparison circuit 48, 49: switching unit

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a television receiver based television receiver capable of preventing degradation of image quality in a television receiver employing a television scanning system.

In a conventional television receiver (hereinafter referred to as TV), 525 scans per screen are executed by using an interlaced scanning method. However, in such a system, when the screen of the receiver is enlarged to form a widescreen TV, there is a problem that the apparent resolution decreases because the interval of the scanning lines becomes large.

Therefore, in recent years, a method of converting an interlaced television signal into a noninterace (or double scanning) signal having the same scan line on the receiver side has been proposed.

FIG. 1 (a) shows the scanning line according to the interlaced scanning method, and FIG. 1 (b) shows the scanning line according to the double scanning method.

In Fig. 1 (a), reference numerals L1, L2, ... L265, ... denote the scanning line numbers, the solid line indicates the odd field and the dotted line indicates the even field. .

Also in FIG. 1 (b), as in FIG. 1 (a), the scan line of the radix field shown by the solid line and the even field scan line shown by the dotted line are scanned, while L1 ', L2', ... The interpolation scanning of L266 ',... Is performed. Thus, by performing the double scanning on the same scan line, the deterioration of image quality is prevented.

However, the following problem arises in such a scanning method.

In FIG. 1, when the luminance change on the scanning line of the screen is represented by 0 (light) and X (dark) with respect to the change in the luminance signal Y in the direction perpendicular to the scanning line, the angle in FIG. While the contrast does not change on the scanning line, in the case of FIG. 1 (b), the L265 with the luminance change X injected between the next syringes is scanned for the L2 'syringes having the luminance change of 0 to repeat the contrast. Line flicker is generated, which causes deterioration in image quality.

In view of this point, Japanese Patent Application No. 81-181973 has proposed a method for performing an interpolation scan based on an arithmetic mean value after arithmetic average of previous and current signals during interpolation scanning.

2 is a block diagram showing an apparatus according to the above method, in which 1 is an antenna, 2 is a tuner, 3 is an image intermediate frequency circuit, 4 is an image detection circuit, and 5 is an image detection circuit 4 Y / C separation circuit for separating the luminance signal (Y) and chroma signal (C) from the image signal output from the image, and 6 is an arithmetic mean distribution scan that arithmetic average and output the previous signal and the current luminance signal during interpolation scanning A conversion circuit, 7 is a color demodulation circuit for demodulating RY and BY signals from chroma signals output from the Y / C separation circuit 5, and 8 and 9 are RY and BY signals from the color demodulation circuit 7 are scanned. A two-time write-in converting circuit for scanning and converting for 10, and 10 is an image matrix circuit for outputting a predetermined RGB signal.

That is, in the above configuration, the color write demodulation signal for the double scan is generated by the double write-type double scan conversion circuits 8 and 9, and the interpolation scan is performed with the arithmetic mean value of the luminance signals during the interpolation scan. The above-mentioned line flicker phenomenon is eliminated.

In the above-described apparatus, however, when the image reproduced on the CRT screen is a still image, that is, when the previous field and the current field are the same image, the interpolated signal interpolated by the arithmetic average is acted as a noise, so that it is in a diagonal line. Block phenomenon occurs.

That is, even in the case where the still images are continuous, the above-described apparatus performs interpolation scanning by arithmetically averaging the previous scan signal and the current scan signal, so that the interpolation signal itself acts as a noise to the still signal.

Therefore, there is a problem in that the image quality is deteriorated on the still image where the image on the screen does not change.

Accordingly, an object of the present invention is to provide a motion adaptive type scanning system television receiver capable of preventing the deterioration of image quality generated during still images. .

In a television receiver configured to insert and interpolate an interpolation signal into an interlaced-type television signal for realizing the above object, a television receiver has an image based on a luminance signal of a detected video signal. Motion detection means for detecting a signal; Characterized in that configured to include.

According to the present invention having the above-described configuration, since the arithmetic mean processing of the luminance signal is selectively performed in accordance with the detection result by the motion detecting means, it is possible to prevent the deterioration of the image quality generated during the still picture.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

3 is a block diagram showing the main components of a distribution-type television receiver according to an embodiment of the present invention. In the drawings, reference numeral 1 is an antenna, 2 is a tuner, 3 is an image intermediate frequency circuit, and 4 is an image detection circuit. And 5 are Y / C separation circuits that separate the luminance signal Y and the chroma signal C from the video signal output from the video detection circuit 4.

Further, reference numeral 31 denotes a motion detection circuit for detecting whether an image is a still image or a moving image based on the luminance signal Y output from the Y / C separation circuit 5, and 32 denotes a previous operation during interpolation scanning. An arithmetic mean circuit which arithmically averages and outputs a luminance signal and a current luminance signal, which selectively outputs arithmetic mean data of the luminance signal Y according to the detection result by the motion detector 31.

Reference numeral 33 denotes a color demodulation circuit for outputting color difference signals of RY and BY based on the chroma signal C output from the Y / C separation circuit 5, and 34 alternately converts these RY and BY signals. The multiplexer (MUX) outputted from the multiplexer (35), 35 is a multiplicative scanning conversion circuit which double-scans and converts the color demodulation signal selected and outputted from the multiplexer (34) by two writing methods, and 36 is applied by this double scanning conversion circuit (35). A demultiplexer (DEMUX) for selectively outputting a color demodulation signal.

FIG. 4 is a diagram showing in detail the configuration of the motion detection circuit 31 and the arithmetic mean circuit 32 in the configuration of FIG. 3. In FIG. 4, reference numeral 41 denotes the output from the Y / C separation circuit 5 of FIG. A first line memory 41 for storing the luminance signal Y in units of one line, and 42 is a second line memory for storing the luminance signals sequentially output from the first line memory 41; An adder for adding the luminance signals output from the first and second line memories 41, 42, and 44 is a division circuit for dividing the addition signal added by the adder 42 by half, and these line memories 41 42, the adder 43, and the divider circuit 44 perform an arithmetic average of the input luminance signal and output the average value to the first switching unit 48 which will be described later.

Reference numeral 45 denotes a field memory 45 for storing data output from the second line memory 42 in units of one field, and 46 denotes output data of the second line memory 42 and the field memory ( A subtractor for subtracting the output data of 45), 47 is a comparison circuit for discriminating whether a moving image or a still image is based on whether the subtraction result by the subtractor 46 is " 0 ", and 48 is the comparison circuit 47 The first switching unit selects and outputs arithmetic mean data of the luminance signal output from the division circuit 44 and data of the previous field output from the field memory 45 according to the comparison result.

In addition, reference numeral 49 is a second switching unit for switching and outputting data output from the second line memory 42 and data output from the first switching unit 48, which is a radix as described in FIG. In the first scan, the data output from the second line memory 42 is output to the image matrix circuit 10. In the even-numbered interpolation scan, the data applied from the first switching unit 48 is output to the image matrix circuit 10. Will be printed.

That is, in the above configuration, the luminance signal of the previous field stored in the field memory 45 and the luminance signal of the current field output from the second line memory 42 are subtracted by the subtractor 46, and the result of subtraction is "0". It is determined whether or not a freeze / still image is determined by.

The first switching unit 48 outputs the arithmetic mean data applied from the division circuit 44 in the case of the moving image as a result of the determination. By outputting one luminance signal, it becomes possible to eliminate the block phenomenon which is a problem in the prior art.

On the other hand, in the configuration of FIG. 3, the chroma signal is subjected to the post-scan conversion processing through the multiplexer 34. FIG.

In general, in the NTSC system, the color difference signals, that is, the frequency bands of R-Y (I) and B-Y (Q) have a band band of 1.5 MHz and 0.6 MHz, respectively. Therefore, in the case of the color difference signal, since it has a smaller amount of information than the luminance signal, as in the conventional configuration, if a separate line memory is provided for each IQ signal, the factor of unnecessarily increasing the manufacturing cost is caused. Will be.

Therefore, in the above embodiment of the present invention, the multiplexer 34 selects and inputs the IQ signal outputted from the color demodulation circuit 33 in FIG. It is.

That is, the I (RY) and Q (BY) signals output from the color demodulation circuit 33 in FIGS. 5A and 3D are shown, and (C) denotes the output of the multiplexer 34, and (D) The outputs of the double scanning transducer 35, (E), and (F) show IQ signals output from the demultiplexer 36, respectively, and image IQ signals (E) and (F) in which one signal overlaps. Even when inputted to the matrix circuit 10, since the information amount of the chroma signal is small as described above, the image quality is not affected.

In this case, of course, the dynamic adaptive scanning method according to the present invention can be realized even if a scanning scanning conversion circuit is separately used for each of the color difference signals R-Y and B-Y.

As described above, according to the present invention, it is possible to realize a scanning-type television receiver which can prevent the deterioration of the image quality generated at the time of still image.

In addition, this invention is not limited to the said Example, It can variously deform and implement within the range which does not deviate from the technical summary of this invention.

Claims (2)

In a television receiver configured to insert and interpolate an interpolation signal into an interlaced scanning television signal, the motion detection means 31 for detecting whether the image is a still image or a moving image based on the luminance signal Y of the detected video signal. And arithmetic averaging means 32 for selectively executing arithmetic averaging of the luminance signal Y in accordance with the detection result by the motion detecting means 31 during interpolation scanning, and a magnification scanning for converting and converting the color difference signal. A television scanning system television set comprising a converting means. 2. The apparatus of claim 1, wherein the first scanning means (34) switches alternately input the color difference signals (RY, BY), and the color difference signal (alternatively inputted by the first switching means 34). RY, BY) and a second scanning means 36 for alternately outputting the color difference signal subjected to the scanning processing by the scanning scanning converter 35. A television receiver system characterized in that the scanning method.