KR950004652Y1 - Luma/chroma separation apparatus - Google Patents

Abstract

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Description

Luminance and Color Signal Separators

1 is a block diagram of a luminance and color signal separation device according to the prior art.

2 is a block diagram of a luminance and color signal separation device according to the present invention.

Figure 3 is a detailed block diagram of a preferred embodiment of the luminance and color signal separation device according to the present invention.

4 is a diagram illustrating a scanning structure and phase of a color carrier signal for an NTSC color signal.

* Explanation of symbols for main parts of the drawings

100: delay unit 200: first operation unit

300: first multiplier 400: second operation unit

500: second multiplier 600: third operation unit

150, 710, 720: latch 800: filter part

The present invention relates to a luminance and color signal separation device, and more particularly, to a luminance and color signal separation device for separating luminance and color signal components corresponding to each pixel of a composite video signal received in an NTSC television receiver.

In the conventional general luminance / color signal separation apparatus, a luminance signal and a color signal are output to the output terminals OUT1 and OUT2 using the low pass filter 1 and the band pass filter 2, as shown in FIG. In addition, not only the horizontal resolution is lowered due to the loss of the high frequency component of the luminance signal transmitted from the transmitter, but also the image quality is degraded due to the interference between the luminance and color signals.

Therefore, the present invention was created in order to solve the above problems, and the luminance which can reduce horizontal resolution deterioration as much as possible by separately processing luminance and color signal which reduced interference phenomenon by using NTSC type scanning structure and color carrier signal phase. And a color signal separation device.

The apparatus of the present invention for achieving the above object, the input of the composite image signal delay unit of the N-order output to delay by one horizontal period unit; the composite image signal of the phase of the color signal of the signal output from each tap of the delay unit is inverted A first operation unit for adding a complex video signal having the same phase as the color signal among the signals output from each tap of the delay unit; A first multiplier unit for dividing the plurality of luminance signals and the composite image signal output from the first operation unit into first predetermined values; Latch means for latching a reference signal output from the delay unit; A second operation unit which adds a plurality of luminance signals output from the first multiplier unit, and adds the output of the latch means and a plurality of composite image signals output from the first multiplier unit; A second multiplier unit for dividing the luminance signal and the composite image signal added by the second operation unit into a second predetermined value; A third operation unit which separates a color signal by subtracting a luminance signal from the composite image signal output from the second multiplier unit; And a low pass filtering of the luminance signal output from the second multiplier, and a high pass filtering of the color signal output from the third calculating unit.

In the luminance and color signal separation device according to the present invention, the delay order N of the delay unit is an odd number, and the first predetermined value of the first multiplier unit or the second predetermined value of the second multiplier unit is 1 /. It is preferable that it is two.

Another apparatus of the present invention for achieving the above object is a delay unit of the N-th order output for inputting the composite video signal delayed by one horizontal period unit; A calculator comprising a first adder for adding composite video signals whose phases of color signals are inverted in the output of the delay unit, and a second adder for adding composite video signals having the same phase of color signals in the output of the delay unit; A luminance signal separating unit for adding and multiplying the luminance signals so that the plurality of luminance signal levels output from the adding unit are equal to the levels of the composite video signals inputted to the delay unit; A composite video signal processor configured to input and multiply the reference signal of the delayer and the plurality of composite video signals output from the adder so as to be equal to the level of the composite video signal inputted to the delay unit; A subtraction unit for subtracting the output of the luminance signal separation unit from the output of the composite image signal processing unit to output a color signal; and low-pass filtering the luminance signal output from the luminance signal separation unit, and high-passing the color signal output from the composite signal processing unit It characterized in that it comprises a filter unit for filtering.

In the luminance and color signal separation device of the present invention, in particular, the delay order N of the delay unit is an odd number, and the composite video signal processor includes latch means for latching the reference signal output from the delay unit for a predetermined time. .

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

2 is a block diagram of a luminance and color signal separation device according to the present invention, and includes an N-th order output delay unit 20 for delaying input of a composite video signal by one horizontal period; A first adder 31 for adding composite image signals whose phases of the color signals are inverted in the output of the delay unit 20, and a second adder for adding composite image signals having the same phase of the color signals in the output of the delay unit 20; An adder 30 composed of 330; A luminance signal separation unit 40 for separating and adding luminance signals by adding and multiplying such that the plurality of luminance signal levels output from the adder 30 are equal to the levels of the composite video signal input to the delay unit 20; A composite video signal for adding and multiplying the reference signal of the delay unit 40 and the plurality of composite video signals output from the adder 30 to be equal to the level of the composite video signal input to the delay unit 20. A processing unit 50; A subtraction unit 60 for subtracting the output of the luminance signal separation unit 40 from the output of the composite image signal processing unit 50 to output a color signal; And a filter unit 70 for low-pass filtering the luminance signal output from the luminance signal separation unit 40 and high-pass filtering the color signal output from the composite image signal processing unit 50.

Referring to FIG. 2, the composite video signal input through the video inputter IN is delayed by one horizontal period from the N-th order delay unit 20 to output N composite video signals. The first adder 31 adds signals in which the phase of the color signal is inverted among the N composite video signals, and the second adder 32 adds signals having the same phase of the color signal.

Since the color signals of the composite image signal input to the first adder 31 are signals whose phases are reversed, the signals output from the first adder 31 are luminance signals from which the color signals are removed, and are also output from the first adder 31. The level of the received luminance signal is higher than the level of the luminance signal input to the delay unit 20.

The luminance signal separating unit 40 receives the output of the first adder 31 and performs addition and multiplication to match the original luminance signal level to separate the luminance signal Y from the composite image signal.

The composite video signal processing unit 50 receives the composite video signal output from the second adder 32 and the reference signal output from the delay unit 20, adds the composite video signal and the reference signal, and then delays 20. The addition and multiplication are performed to match the level of the signal input to the input signal. At this time, when the delay order and the number of delay taps N of the delay unit 20 are odd, the delay signal output from the N / 2 th tap is preferably used as the reference signal.

The subtraction unit 60 receives the outputs of the luminance signal separation unit 40 and the composite image signal processing unit 50 and subtracts the luminance signal Y from the composite image signal Y + C to output the color signal C. .

Therefore, the luminance signal output from the luminance signal separator 40 is filtered by the low pass filter 71 of the filter unit 70 and the luminance signal is separated, and the luminance signal output from the subtractor 60 is a high pass filter. In 72, the color signal is separated.

In other words, by adding the pixels of adjacent horizontal lines (pixels whose phases are inverted in phase) by using the inversion of the phase of the color carrier signal every one horizontal scanning period, the luminance signal is separated from the composite image signal, thereby causing the high frequency component of the luminance signal. The luminance signal and the color signal can be separated without being lost.

FIG. 3 is a detailed block diagram of a luminance and color signal separation device having a fifth number of taps of the delay unit 100 as a preferred embodiment of the luminance and color signal separation device according to the present invention.

According to FIG. 3, the luminance and color signal separation device of the present invention is a delay device (110, 120, 130, 140) connected in series to delay the video signal input through the digital video input terminal (IN) by one horizontal period A first operation unit 200 provided with a delay unit 100 provided with a first and second adders 210, 220, and 230 for adding data output from each tap of the delay unit 100, and the first operation unit 200. The first multiplier 300 provided with the multipliers 310, 320, and 330 for dividing the data calculated by the adders 210, 220, and 230 of the calculator 200 into a first predetermined value, and the local data. An adder 410 for adding a latch 150 for latching a reference signal, data output from the multipliers 310, 320, 330 of the first multiplier unit 300, and an output of the latch 150. The second operation unit 400 provided with the 420, and the adders 410, 420 of the second operation unit 400 A third operation unit 600 for adding data output from the multipliers 510 and 520 of the multiplier unit 500 for dividing the data into a second predetermined value, and the output data and the multiplier of the third operation unit 600. Latch (150, 710, 720) for delay adjustment of the output data of the (510), respectively, and a low pass filter for low pass filtering and band pass filtering each data passed through the latch (150, 710, 720) ( 810 and the filter unit 800 provided with a low pass filter (820).

The present invention having the configuration as described above will be described in detail with reference to FIGS. 2 and 3 as follows.

The luminance and color signal separation device of the present invention detects the luminance and color signal information of the current pixel by using the NTSC scanning structure and the phase of the color subcarrier signal, as shown in FIG. Since the color carrier signals are inverted in phase for each horizontal scanning line, the tabs of the 1H delayers 110, 120, 130, and 140 of the delay unit 100 are outputted with the phases of the color carrier signals inverted. . In addition, adjacent pixel information a, b, c, d output from each tap A, B, C, D, E of the delay unit 100 are arranged on the same time axis.

Meanwhile, the A tap output data of the delay element 110 constituting the delay unit 100 and the E tap output data of the delay element 140 are summed by the adder 230 of the first operation unit 200, and this signal is obtained. Is input to the multiplier 330 of the first multiplier 300 and divided by 1/1.

The reason for dividing by 1/2 in the multiplier 330 is to make the original level since the level of the composite video signal output from the adder 230 is greater than the level of the composite video signal input to the retarder.

At this time, each tap (A, B, C, D, E) signal of the delay elements (110, 120, 130, 140) constituting the delay unit 100 of FIG. 2 is a, b, c, d, If the phase relationship of e and the phase in phase, the delay unit 100 is composed of four delay units (110, 120, 130, 140) to configure the number of taps (A, B, C, D, E) in fifth order.

The higher the order of the retarder 100, the higher the frequency characteristics of the filter. However, since the processing is performed by using too much surrounding pixel information, it may adversely affect the output image. Pixel information is used.

The data divided by 1/2 in the multiplier 330 and the C-tap output data latched in the latch 150 are added by the adder 420 of the second operation unit 400 to multiply the multiplier of the second multiplier unit 500. 520 is sent.

On the other hand, the C tap data of the delay unit 100 is processed by adding the data of the B tap and the D tap with the adders 210 and 220 of the first operation unit 200, respectively. The two input data are completely inverted because the phase of the color carrier signal is inverted.

Data respectively transmitted from the adders 210 and 220 to the multipliers 310 and 320 is divided into 1/2, and the added data is transmitted to the multiplier 510 of the second multiplier 500.

Each data divided by 1/2 in the multipliers 510 and 520 is added or subtracted by the third operation unit 600 to transmit only the data corresponding to the color signal component from which the luminance component is removed to the latch 720.

At this time, the latch 720 latches the data input from the third operation unit 600 and transmits the latched data to the band pass filter 820 of the filter unit 800. The bandpass filter 820 latches the input data and transmits the latched data to the bandpass filter 820 of the filter unit 800. The bandpass filter 820 filters the input data and transmits the color signal from which the luminance component is removed to the output terminal OUT2.

On the other hand, the latch 710 latches the data transmitted from the multiplier 510 and transmits the data to the low pass filter 810 of the filter unit 800, and the luminance signal filtered by the low pass filter 810 is output. Output to (OUT1).

In the siling example of FIG. 3, the device separates the luminance signal from the color signal using adjacent pixel information. When selecting pixel information instead of adjacent pixels, the phase structure of the scanning structure and the color subcarrier signal shown in FIG. 4 is considered. It is obvious that it can be implemented as described above.

As described above, the present invention adopts the digital luminance / color signal separation method using the luminance and color signal information of the surrounding line to prevent resolution degradation and to eliminate crosstalk between luminance and color signals. There is an advantage that can expect a clear image without this.

Claims (7)

A delay unit of the N-th order output delaying the composite video signal by one horizontal period unit; A first operation unit which adds a composite video signal in which the phase of the color signal is inverted among the signals output from each tap of the delay unit and outputs a luminance signal, and adds a composite video signal having the same phase of the color signal among the signals output from each tap of the delay unit; ; A first multiplier unit for dividing the plurality of luminance signals and the composite image signal output from the first operation unit into first predetermined values; Latch means for latching a reference signal output from the delay unit; A second operation unit which adds a plurality of luminance signals output from the first multiplier unit, and adds the output signal of the latch means and the plurality of composite image signals output from the first multiplier unit; A second multiplier unit for dividing the luminance signal and the composite image signal added by the second operation unit into a second predetermined value; A third operation unit which separates a color signal by subtracting a luminance signal from the composite image signal output from the second multiplier unit; And a filter unit for low pass filtering the luminance signal output from the second multiplier unit, and a high pass filtering the color signal output from the third operation unit. The luminance and color signal separation apparatus according to claim 1, wherein the delay order N of the delay unit is odd. The apparatus of claim 1, wherein the first predetermined value of the first multiplier portion or the second predetermined value of the second multiplier portion is 1/2. A delay unit of the N-th order output delaying the composite video signal by one horizontal period unit; An adder including a first adder for adding composite video signals in which the phase of the color signal is inverted in the output of the delay unit, and a second adder for adding a composite video signal having the same phase in the color signal from the output of the delay unit; A luminance signal separating unit for adding and multiplying the luminance signals so that the plurality of luminance signal levels output from the adding unit are equal to the levels of the composite video signals inputted to the delay unit; A composite video signal processor configured to input and multiply the reference signal of the delayer and the plurality of composite video signals output from the adder so as to be equal to the level of the composite video signal inputted to the delay unit; A subtraction unit for subtracting the output of the luminance signal separation unit from the output of the composite image signal processing unit to output a color signal; And a filter unit for low-pass filtering the luminance signal output from the luminance signal separation unit and high-pass filtering the color signal output from the composite signal processing unit. 5. The luminance and color signal separation apparatus according to claim 4, wherein the delay order N of the delay unit is odd. 5. The luminance and color signal separation device of claim 4, wherein the reference signal output from the delay unit is an output signal of (N + 1) / 2 taps. The luminance and color signal separation apparatus of claim 4, wherein the composite image signal processing unit comprises a means for latching the reference signal output from the delay unit for a predetermined time.