KR0164789B1 - Distortion correction apparatus of blue back picture - Google Patents

Abstract

1. The technical field to which the invention described in the claims belongs:

A color television adopting a trinoma system is provided.

2. The technical problem to be solved by the invention:

Trinoma system Provides a blue back screen distortion correction device for stabilizing blue back screen processing by adjusting vertical tilt and magnitude data for vertical deflection when there is no video signal in a received signal in a color television.

3. Summary of the solution of the invention:

The apparatus for processing a blue back screen without a video signal in a color television of a trinoma system detects the presence or absence of a video signal in a received signal and the second signal when the video signal is present and the second when the video signal is not present. A signal and deflection processing unit for outputting a signal, processing a video signal and a color signal of the video signal, and adjusting and outputting a vertical deflection signal based on a first vertical deflection data and a second vertical deflection data; A microcomputer connected through a bus line and a processor to output the first vertical deflection data when the first signal is input, and output the second vertical deflection data for the blue back screen processing when the second signal is input; And an amplifier for amplifying and outputting the signal and the vertical deflection signal of the deflection processing unit.

4. Important uses of the invention:

Trinoma System In color television, this is implemented to correct the distortion of the blue back screen when there is no video signal in the received signal.

Description

Blue back screen distortion correction device

1A through 1C are vertical waveform diagrams for processing a blue back screen in a television of the prior art.

2 is a system block diagram of an apparatus for blue back screen distortion correction in a television of the present invention.

3A to 3B are vertical waveform diagrams for processing the blue back screen according to FIG.

* Explanation of symbols for main parts of the drawings

220: microcomputer 222: signal and deflection processing unit

224: Amplifier

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to color television employing a trinorma system, and more particularly to an apparatus for processing a blue back screen.

Generally, televisions are classified into NTSC system, PAL-M system and PAL-N system according to the color system. Thus, countries around the world are doing television broadcasting in accordance with their television color scheme. Because of the different broadcasting systems of different countries, televisions with different color schemes cannot receive broadcast signals. Since it is inconvenient and uneconomical, color television adopting the trinoma system employs both NTSC, PAL-M, and PAL-N methods, so broadcast reception is possible for these methods.

Typically, televisions employing a trinoma system are divided into 60Hz and 50Hz vertical frequencies. The vertical frequency of 60 Hz is for NTSC, PAL-M system. The vertical frequency of 50 Hz is for the PAL-N method. Accordingly, when the video signal is not included in the received signal, the trinoma system generally uses a vertical frequency of 40 Hz based on 50 Hz.

Vertical waveforms for processing a blue back screen in a television of the prior art are shown in FIGS. 1A, 1B and 1C. Hereinafter, a description will be given with reference to FIGS. 1a to 1c.

FIG. 1A is a vertical waveform when receiving a vertical frequency of 60 Hz. 1B is a vertical waveform when receiving a vertical frequency of 50 Hz. Since the first and the first diagrams are vertically synchronized with the signal, the first and second diagrams have no significant effect on scanning on the screen. However, in FIG. 1C, the distortion of the waveform is increased as the duty of the waveform increases to 40 Hz in the slope and magnitude of the vertical waveforms of 60 Hz and 50 Hz. Therefore, when the blue back screen is processed when there is no video signal in the received signal, distortion occurs at the bottom of the screen.

Accordingly, an object of the present invention is to provide a blue back screen distortion correction device for stably adjusting a blue back screen by adjusting vertical tilt and magnitude data for vertical deflection when there is no video signal in a received signal in a trinoma system color television. have.

In order to achieve the above object of the present invention, an apparatus for processing a blue back screen without a video signal in a color television of a trinoma system, the first signal when the presence of the video signal is detected by detecting the presence or absence of a video signal And outputting a second signal when the video signal does not exist, processing a video signal and a color signal of the video signal, and adjusting and outputting a vertical deflection signal based on a first vertical deflection data and a second vertical deflection data. Connected to the signal and deflection processing unit, the signal and deflection processing unit, and the bus line to output the first vertical deflection data when the first signal is inputted, and to output the blue back screen when the second signal is inputted. A microcomputer for outputting the second vertical deflection data, and an amplifier for amplifying the signal and the vertical deflection signal of the deflection processing unit. It is characterized by.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that like elements in the figures represent like reference numerals wherever possible.

As used herein, the term blue back screen refers to processing a blue signal when a video signal does not exist in a received signal and displaying the same on a screen.

A system block diagram of an apparatus for blue back screen distortion correction in a television of the present invention is shown in FIG. Hereinafter, a description will be given with reference to FIG. 2.

The signal and deflection processor 222 detects the presence or absence of an image signal in the demodulated signal. When the video signal is present, the video signal and color signal are processed and the deflection signal is processed and output. The microcomputer 220 connected through the signal and deflection processor 222 and the bus line 221 has a storage area. The first vertical deflection data and the second vertical deflection data are stored in the storage area. Accordingly, the microcomputer 220 outputs the first vertical deflection data or the second vertical deflection data according to the image signal presence signal of the signal and deflection processing unit 222. The amplifier 224 amplifies and outputs the output signal of the signal and deflection processing unit 222.

3 is a waveform diagram of a signal relating to the vertical deflection output from the amplifier 224 of FIG. Hereinafter, the configuration of FIG. 2 and the FIG. 3 will be described in detail.

The signal and deflection processor 222 inputs the received signal to determine the presence of the video signal. First, when the video signal exists, the signal and deflection processor 222 outputs a first signal S1. The microcomputer 220 inputs the first signal S1 and outputs the first vertical deflection data D1 stored in the storage area to the signal and deflection processing unit 222 through the bus line 221. Accordingly, the signal and deflection processor 222 adjusts the vertical inclination and the vertical size based on the first vertical deflection data D1 and outputs the vertical deflection signal. The amplifier 224 inputs, amplifies, and outputs the signal output from the signal and deflection processing unit 222. At this time, the output signal is a vertical deflection signal such as the waveform diagram of FIG. 1a or 1b.

Secondly, a case in which the video signal does not exist will be described. This is to prevent distortion of the blue back screen to be solved by the present invention. The signal and deflection processor 222 outputs a second signal S2 when the video signal does not exist. The microcomputer outputs the second vertical deflection data D2 to the signal and deflection processing unit 222 through the bus line 221 based on the second signal S2. The signal and deflection processing unit 222 then outputs a vertical deflection signal by adjusting the vertical inclination and the vertical size based on the second vertical deflection data D2. That is, the waveform of the vertical signal is changed by changing the data on the vertical deflection by the second vertical deflection data D2. The amplifier 224 inputs, amplifies, and outputs the signal output from the signal and deflection processing unit 222. In this case, the output signal is a vertical deflection signal such as the waveform diagrams of FIGS. 3A and 3B.

FIG. 3a shows the change of the vertical slope changed by the second vertical deflection data D2. That is, 312 is a vertical slope before the change, and 314 is a vertical slope after the change according to the present invention. If the vertical slope of 312 is an unknown number X, the vertical slope of 314 is X + ΔX. Where ΔX is the second vertical deflection data D2.

FIG. 3b shows the change in the vertical size changed by the second vertical deflection data D2. That is, 316 is the vertical size before the change, and 318 is the vertical size after the change according to the present invention. If the vertical size of 316 is another unknown number Y, the vertical size of 318 is Y + ΔY. Where DELTA Y is the second vertical deflection data D2.

If the operator sets large changes in ΔX and ΔY, the size of the screen becomes too small and must be set appropriately.

As described above, when the blue back screen processing is applied to the color television adopting the trima system of the present invention, the vertical frequency is divided into 60 Hz and 50 Hz, thereby preventing distortion of the screen. It stores the second vertical deflection data for the blue back screen processing in the microcomputer 220 and the vertical slope and the vertical size of the vertical signal for scanning on the screen when there is no image signal in the received signal by the second vertical deflection data. The deflection processor 222 outputs a signal regarding vertical deflection according to the blue back screen.

Claims (2)

An apparatus for processing a blue back screen without an image signal in a color television of a trinoma system, the apparatus comprising: detecting a presence or absence of an image signal from a received signal, when the first signal and the image signal do not exist A signal and deflection processing means for outputting a second signal, processing a video signal and a color signal of the video signal, and adjusting and outputting a vertical deflection signal based on a first vertical deflection data and a second vertical deflection data; The first vertical deflection data is output when the first signal is input through the signal and deflection processing means and the bus line, and the second vertical deflection data for the blue back screen processing is input when the second signal is input. Blue back screen distortion correction characterized in that it comprises a micom for outputting, and an amplifier for amplifying and outputting the signal and the vertical deflection signal of the deflection processing means Device. And the first and second vertical deflection data are vertical slope data and vertical size data of a waveform of a vertical signal.