KR940011886B1 - Super impose system in camcoder - Google Patents

Abstract

In a super impose system performed in such a manner that a luminance signal of two digit is stored in a static RAM by comparator so that a title signal and a camera color signal of the title generating part received from a matrix/mixer unit are super imposed with the EE screen of the camera according to a blank signal. It is disclosed a super impose system of a camcoder, including a buffer for buffering a luminance signal of the camera or video playback signal; a lower limiter for removing a synchronous part of the output signals of the buffer; a differential controlling amplifier for differentially controlling the output for the limiter; an adding amplifier for adding the signal of the differential controlling amplifier and the signal of the luminance signal of the limiter; and comparators for comparing the signal of the adding amplifier and the luminance signal of the limiter and then generating a title signal.

Description

Camcorder Super Impose System

1 is a block diagram of a super impose system of a conventional camcorder.

2 is a block diagram of a super impose system of the camcorder according to the present invention.

3 is a waveform diagram of each part according to FIG.

4 is a superimposed screen display according to the present invention.

* Explanation of symbols for main parts of the drawings

1 matrix / mixer 2 encoder

3: micom 5: key board

4: Title generator 6: Stack tick ram

7, 13, 14: comparator 8: sync tip clamp

9: low pass filter 11: buffer

12: low limiter 15: differential control amplifier

16: addition amplifier

The present invention relates to a super impose system of a camcorder, and more particularly, to a super impose system of a camcorder for extracting and emphasizing only an edge portion of an input video signal to superimpose it.

The superimposition system of the conventional camcorder has a low pass filter 9 for filtering the luminance (Y) signal of the camera output as shown in FIG. 1, and the output of the low pass filter 9 is fixed to a certain level. A sync tip clamp 8, a comparator 7 for binarizing the output of the sync tip clamp 8 with a reference value, and a static ram for storing the output data of the comparator 7 6), a title generating unit 4 for outputting title color signals R, G, and BLK signals in accordance with the control signal of the microcomputer 3, a title color signal of the title generating unit 4, and a camera color signal; Matrix / mixer 1 to output color difference signals (RY, GY, BY) and color difference signals of the matrix / mixer 1, and output luminance (Y) and color (C) signals. It consists of an encoder (2).

Here, reference numeral 5 denotes a keyboard.

In the conventional circuit configured as described above, since the luminance (Y) signal of the camera output is higher in frequency than the memory degree, the luminance (Y) signal through the filter (9) is first passed through the low pass filter (9). It is input to the comparator 7 for binarization, and is input to the comparator 7 by applying a sync tip clamp so that the level of binarization does not change depending on the signal level.

Compared to the reference value adjusted by the variable resistor VR, the bit is input to the title generator (or memory controller) as one bit value of "high" and "low", and is sequentially stored in the static ram 6.

The title color signals R, G, and B of the title generator 4 are mixed with the color (R ', G', B ') signals of the camera in the matrix / mixer 1, where the static ram ( The data stored in 6) is output as a blanking signal to switch the camera's EE output and the title (superimposed) output.

In the matrix / mixer unit 1, the color signal of the camera and the title color signal are matrixed and mixed to output the color difference signals RY and BY, and the luminance (Y) signal and the color (C) are passed through the encoder (2). It is output as a signal.

Unlike the super impose system of the conventional camcorder, in order to implement a more specific super impose system, a differential signal is controlled and compared with a win luminance signal to detect only the edge part and store the waveform in a memory. The super impose system of the camcorder to be impose was created, which will be described in detail with reference to the accompanying drawings.

2 is a block diagram illustrating the superimposition system of the camcorder according to the present invention, wherein a buffer 11 for buffering a luminance (Y) signal among a camera or playback video signal and a low region for removing a synchronization portion from an output signal of the buffer 11 are shown. A meter 12, a differential control amplifier 15 for differentially amplifying the output of the limiter 12, an addition amplifier for adding the signal of the differential control amplifier 15 and the luminance signal of the limiter 12 ( 16, the comparator 13 (14) which compares the output signal of this addition amplifier 16, and the luminance signal of the said limiter 12, and the combined output signal (title luminance signal of this comparator 13, 14). ), A title generating section (4) for outputting title color signals (R, G, B) and a blank (BLK) signal in accordance with the control signal of the microcomputer (3), and the title generating section. A matrix / mix which outputs the color difference signals RY and BY by matrixing and mixing the title color signal (4) and the color signals R ', G' and B 'of the camera. It consists of the western part 1 and the encoder 2 which receives the color-difference signal of this matrix / mixer part 1, and outputs it separately as the luminance (Y) and the color (C) signal.

Referring to the operation and effect of the present invention configured as described above in detail.

The luminance Y signal of the camera or the playback video signal, such as the third (a) degree, is buffered through the buffer 11 and then the synchronization portion is cut off as shown in the third (b) while passing through the lower limiter 12. Only the pure luminance signal remains. Pure luminance signals passing through the limiter 12 are applied to the inverting and non-inverting terminals of the comparators 13 and 14, respectively, and to the differential control amplifier 15.

The pure luminance signal is differentially controlled by the differential control amplifier 15, which obtains a signal as shown in FIG. 3 (c) in which only the boundary of the luminance signal, that is, the portion where the luminance level changes rapidly.

The output signal of the differential control amplifier 15 is combined with the pure luminance signal of the limiter 12 by the addition amplifier 16 to obtain a signal as shown in FIG. 3 (d).

The output signal of the addition amplifier 16 is applied to each of the non-inverting and inverting terminals of the comparator 13 to be compared with the pure luminance signal, and the signal compared by the comparators 13 and 14 is the third (e). Signals as shown in Fig. 3 (f) are compared and output.

As described above, when the outputs respectively compared through the comparators 13 and 14 are combined as shown in FIG. 3 (g) and sent to the title generator 4 as a title signal, the static RAM (through the title generator 4) is output. 6), the title color signals R, G, and B in the title generator 4 are converted into the camera color signals R ', G', in the matrix / mixer 1 according to the control signal of the microcomputer 3; B '), wherein the data stored in the static ram 6 is output as a blank signal to switch the EE output and the title output (superimpose) of the camera.

In the matrix / mixer 1, the color signals R ', G' and B 'of the camera and the tight color signals R, G and B are matrixed and mixed to output the color difference signals RY and BY, which are then mixed. The signal passes through the encoder 2 into a luminance (Y) signal and a color signal (C) and is transmitted as a video.

In this way, a more unusual superimposed screen like FIG. 4 is obtained. The boundary (edge) of the brightness level, that is, the edge of the character, is superimposed on the background screen.

As described in detail above, the present invention extracts only the boundary portion of the video screen and superimposes it to obtain a screen effect different from that of the conventional art.

Claims (1)

After storing the binarized luminance signal through the comparator in the static RAM 6, the title signal and the camera signal of the title generator 4 for outputting the title color signal according to the control signal of the microcomputer 3 are converted into the matrix / mixer unit 1. In the superimposition system which superimposes the EE screen of a camera according to a BLK signal, the buffer 11 which buffers the luminance signal of a camera or playback video signal, and the output signal of this buffer A low limiter 12 for removing the synchronization portion, a differential control amplifier 15 for differentially controlling the output of the limiter 12, a signal of the differential control amplifier and a luminance signal of the limiter 12 are added; And a comparator (13) and (14) for producing a title signal by comparing the addition amplifier (16) with the signal of the addition amplifier (16) and the luminance signal of the limiter (12), respectively. Super Impose Sea System.