KR100232958B1 - Broadcasting mode determination apparatus and method thereof - Google Patents

Abstract

The present invention relates to a broadcast method discriminating apparatus and method, and more particularly, comprising: sync signal separating means for generating a separated sync signal by separating a sync signal from a composite video signal; Pulse generating means which is reset by the synchronizing signal of the synchronizing signal separating means and counts a master clock signal input from the outside to output a burst gate pulse; Burst amplifying means for amplifying and outputting a color burst signal of the composite video signal in synchronization with the rising edge of the burst gate pulse of the pulse generating means; Detecting means for counting the amplified color burst signal every horizontal syringe to detect a first broadcast method; And output means for outputting a detection signal output from the detection means as a broadcast mode determination signal in response to a falling edge of the burst gate pulse.

Therefore, the present invention can automatically determine the broadcasting method by detecting the color carrier using a color burst signal, thereby providing convenience to the general public who are not familiar with the broadcasting method.

In addition, by being implemented in a digital manner, there is a feature that is stronger in error and noise than the analog method.

Description

Broadcasting method discrimination apparatus and method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcast method discriminating apparatus and method, and more particularly, to a broadcast method discriminating apparatus implemented in a digital manner to automatically detect a broadcast method by detecting a color carrier using a color burst signal.

Generally, there are NTSC, PAL, PAL-M, PAL-N, and SECAM types of terrestrial broadcasting systems used in various countries around the world, and each country adopts a method suitable for its own characteristics. For example, the United States, Japan, and Korea use NTSC, Germany and Western Europe, including China, and PAL, and France and Eastern Europe use SECAM. These schemes have their own specifications. For example, NTSC uses 3.579545 MHz, and PAL uses 4.433618 MHz of sub-carriers. Accordingly, the TV receiving end receives the terrestrial wave and detects the difference between the respective schemes from the received composite video signal to determine the broadcasting scheme.

However, a conventional broadcasting method discriminator is manufactured using an analog integrated circuit, and separates a color signal from a received composite video signal to detect a color carrier 3.58 MHz / 4.43 MHz component, and separates the color carrier from the separated color signal. Detect 3.58 MHz / 4.43 MHz

In addition, the implementation of the broadcast type discrimination apparatus using such an analog method complicates the peripheral application and is difficult to realize since it is affected by the peripheral elements, that is, the resistance, the inductor, and the capacitor, and is sensitive to temperature characteristics or noise. There are disadvantages. Nowadays, with the development of digital processing technology, the circuit can be simpler and less error-prone because it can be easily implemented as an application specific semiconductor (ASIC).

In addition, since color signals are used to detect color carriers, there are problems in that the cost increases because a filter suitable for each broadcasting method, i.e., a band pass filter of 3.58 MHz and 4.43 MHz, must be used.

In addition, it is possible to use a video device that can handle a variety of broadcast methods, in this case, it is difficult for consumers unfamiliar with the broadcast method to operate the system according to the input source.

SUMMARY OF THE INVENTION An object of the present invention is to provide a broadcast method discrimination apparatus digitally implemented to automatically detect a broadcast method by detecting a color carrier using a color burst signal to solve the above problems.

In order to solve the above problems, the apparatus of the present invention comprises: a synchronization signal separating means for generating a separate synchronization signal by separating the synchronization signal from the composite video signal; Pulse generating means which is reset by the synchronizing signal of the synchronizing signal separating means and counts a master clock signal input from the outside to output a burst gate pulse; Burst amplifying means for amplifying and outputting a color burst signal of the composite video signal in synchronization with the rising edge of the burst gate pulse of the pulse generating means; Detecting means for counting the amplified color burst signal every horizontal syringe to detect a first broadcast method; And output means for outputting a detection signal output from the detection means as a broadcast mode determination signal in response to a falling edge of the burst gate pulse.

In order to solve the above problem, the method includes the steps of: separating a synchronization signal from a received composite video signal; Generating a burst gate pulse by counting an externally input master clock signal every horizontal scanning period; Extracting and amplifying a color burst signal from the composite video signal; Counting a predetermined period of the amplified color burst signal; Counting the master clock signal by a predetermined period and determining whether a counting value coincides with a preset value; And generating a first broadcast mode determination signal when the counting value matches a preset value, and generating a second broadcast mode determination signal when the counting value does not match.

1 is a circuit diagram for explaining a broadcasting system discrimination apparatus according to the present invention.

Fig. 2 is a waveform diagram showing waveforms generated in each part of the broadcasting system discrimination apparatus according to the present invention.

3 is a flowchart for explaining a broadcasting method discrimination method according to the present invention;

* Explanation of symbols for the main parts of the drawings.

10; A synchronization signal separator 20; Pulse generator

40; Burst amplifier 60; Detection unit 80; Output

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

FIG. 1 is a broadcasting system discrimination apparatus according to the present invention, and as shown, a synchronization signal separation unit 10 for generating a synchronization signal H_SYNC by separating a synchronization signal from a composite video signal CVS, and synchronization. A pulse generator 20 which is reset by the synchronization signal H_SYNC of the signal separator 10 and counts a master clock signal EX_CLK input from the outside to output a burst gate pulse (BGP); And a burst amplifier 40 for amplifying and outputting a color burst signal of the composite video signal CVS in synchronization with the rising edge of the burst gate pulse BGP of the pulse generator 20, and the amplification every horizontal syringe. A falling edge of the burst gate pulse BGP to detect the detection unit 60 and the detection signal output from the detection unit 60 by counting the color burst signal and detecting the first broadcast method (broadcast method using a color carrier of 3.58 MHz). Broadcast in response to An output unit 80 for outputting a discrimination signal expression.

The pulse generator 20 is reset to the synchronous signal H_SYNC of the synchronous signal separator 10, and the first counter 21 and the synchronous signal separator 10 that count the predetermined period of the master clock signal. The first flip-flop 22 is reset to the synchronization signal H_SYNC and outputs a burst gate pulse BGP in synchronization with the master clock signal EX_CLK.

The detection unit 60 is reset to the synchronization signal H_SYNC of the synchronization signal separation unit 10 and the second counter 61 which counts the color burst signal CBS amplified by the burst amplification unit 40; And a second flip-flop 42 which is reset to the synchronous signal H_SYNC of the synchronous signal separator 10 and generates a pulse which is sustained for a partial period in the count period in synchronization with the amplified color burst signal, and the synchronous signal separation. The third counter 64 is reset to the synchronization signal H_SYNC of the unit 10 and counts the master clock signal at the rising edge of the pulse provided by the second flip-flop 62.

The output unit 80 is synchronized with the master clock signal EX_CLK and the third flip-flop 81 delays the output signal of the detection unit 60 and outputs the synchronization signal H_SYNC of the synchronization signal separation unit 10. A fourth flip-flop 82, which is reset to the power supply voltage, is supplied with the power supply voltage VCC to the first and second inputs and is synchronized with the rising edge of the third flip-flop 81 output signal to generate a corresponding output signal. And an inverter IN for inverting the burst gate pulse BGP of the pulse generator 20 and a delay signal for outputting the output signal of the fourth flip-flop 82 in response to the output signal of the inverter IN. It consists of five flip-flops 84.

The first, second and fourth flip-flops are composed of JK flipflops, and the third and fifth flip-flops are composed of D flipflops.

The operation of the preferred embodiment configured as described above will be described with reference to the waveform diagram of FIG. 2 and the flowchart of FIG. 3.

In FIG. 2, waveform a) is a composite video signal CVS composed of a synchronization signal, a color burst signal, and an image signal. First, the sync signal separator 10 separates only the sync signal H_SYNC from the composite video signal CVS (first step), and the waveform b in FIG. 2 represents the separated sync signal H_SYNC.

Then, referring to the waveform d of FIG. 2, the first counter 21 of the pulse generator 20 is reset at the falling edge of the separated synchronization signal H_SYNC, and starts from the rising edge of the synchronization signal H_SYNC. The master clock signal EX_CLK input to the first counter 21 is counted. At this time, the counted section counts the second to 100th section. The first flip-flop 22 is reset at the falling edge of the separated synchronization signal H_SYNC, and receives the count signals from the first counter 21 to the first and second inputs at the rising edge of the second master clock. Transitioning to " high " state, generating a burst gate pulse BGP which continuously maintains this " high " state and then transitions to " low " state at the 100th master clock (second step). Here, the master clock EX_CLK has a frequency of 26 MHz.

See waveform e) of FIG. 2. The burst amplifier 40 extracts and amplifies only a color burst signal from the composite video signal CVS in synchronization with a burst gate pulse BGP which is a window pulse (fourth step).

After the fourth step, the second counter 61 of the detector 60 is reset at the falling edge of the separated synchronization signal H_SYNC and counts the amplified color burst signal CBS (sixth step). . The second flip-flop 62, which receives the count values as the first and second input signals, transitions to the “high” state at the first input signal, the count value 3, and maintains the “high” state before the second input signal. The window is created by returning to the "low" state at the in count value 7. Waveform f in FIG. 2 shows the output signal of the second flip-flop 62.

At this time, the count interval of the second counter 61 according to each broadcasting method is as follows.

NTSC358: Fsc = 3.579545 MHz = 279 GHz, 279 × 4 = 1116 GHz

PAL: Fsc = 4.433619MHz = 226 Hz, 226 × 4 = 904 Hz

PAL_M: Fsc = 3.575611MHz = 280 Hz, 280 × 4 = 1120 Hz

PAL_N: Fsc = 3.582056MHz = 279㎱, 279 × 4 = 1116㎱

Here, Fsc means the frequency of the color carrier.

The reason why the count period is multiplied by 4 is because the second counter 61 decodes three to seven, that is, four periods.

The third counter 64 is reset at the falling edge of the separated synchronization signal H_SYNC and counts the master clock signal EX_CLK which is enabled and input at the rising edge of the output signal of the second flip-flop 62. In step 8, the first broadcast method is determined (step 8). Here, the third counter 64 counts up to 27. If the received composite video signal is the first broadcast method, that is, the color carrier is 3.58 MHz, the counter outputs the 27th master clock signal EX_CLK as shown in waveform g) of FIG. If the carrier is 4.43 MHz, a "low" signal is generated.

At this time, the count value of each broadcasting method is as follows.

NTSC: 1116㎱ / 38㎱ = 29.3 = 29

PAL: 226㎱ / 38㎱ = 23.7 = 23

PAL_M: 280㎱ / 38㎱ = 29.4 = 29 units

PAL_N: 279㎱ / 38㎱ = 29.3 = 29

(However, the period of the master clock signal EX_CLK is 38 ms.)

Then, as in the waveform h) of FIG. 2, the third flip-flop 81 of the output unit 80 delays and outputs the 27th master clock signal EX_CLK in synchronization with the master clock signal. As in waveform i), the fourth flip-flop 82, which receives the power supply voltage as the first and second inputs, is reset at the falling edge of the separated synchronization signal H_SYNC, and the third flip-flop 81 By synchronizing to the rising edge of the output signal, the NTSC, PAL-M and PAL-N schemes are decoded when the color carrier is 3.58 MHz, and the output is "low" when the color carrier is 4.43 MHz. By generating, the PAL scheme is not decoded, and then, as in waveform j) of FIG. 2, the fifth flip-flop 84 is synchronized with the inverted signal of the burst gate pulse BGP. The output signal is delayed and outputted. In the case of the 3.58 MHz component, it is "high". Outputs "low".

In this way, 3.58 MHz / 4.43 MHz can be digitally determined.

Therefore, as described above, the present invention can automatically determine a broadcast method by detecting a color carrier using a color burst signal, thereby providing convenience to the general public who are not familiar with the broadcast method.

In addition, by being implemented in a digital manner, there is a feature that is stronger in error and noise than the analog method.

Claims (6)

A sync signal separator for separating a horizontal sync signal from the composite video signal; A pulse which is reset by the horizontal synchronization signal separated by the synchronization signal separation unit and counts an external master clock signal to generate a burst gate pulse signal having a width of a section in which a color burst signal is mixed with the composite video signal. Generator; A burst amplifier for detecting, amplifying and outputting a color burst signal in a composite video signal according to the burst gate pulse signal generated by the pulse generator; A detector for counting the master clock signal during a period of a predetermined number of color burst signals outputted from the burst amplifier while being reset by the horizontal sync signal separated by the sync signal separator; And And an output unit operating on the falling edge of the burst gate pulse output by the pulse generator to output a detection signal output from the detector as a broadcast mode determination signal. According to claim 1, wherein the pulse generator; A first counter that is reset by the horizontal synchronization signal separated by the synchronization signal separator and counts the master clock signal in a predetermined number range; And A first signal which is reset by the horizontal synchronization signal separated by the synchronization signal separation unit and outputs a pulse signal having a width in a range in which the first counter counts the master clock signal in a predetermined number as a burst gate pulse signal; Broadcasting method determination device characterized in that consisting of flip-flop. The apparatus of claim 1, wherein the detection unit; A second counter that is reset by the horizontal synchronization signal separated by the synchronization signal separator and counts a predetermined number of ranges of the color burst signal output from the burst amplifier; The second counter has a width in which the second counter counts a predetermined number of color burst signals in accordance with the color burst signal reset by the horizontal sync signal separated by the sync signal separator and output from the burst amplifier. A second flip-flop for generating a pulse signal; And And a third counter which is reset by the horizontal synchronization signal separated by the synchronization signal separation unit and counts the master clock signal during the period in which the second flip-flop outputs a pulse signal. The method of claim 3, wherein the width of the range in which the second counter counts the color burst signal; Broadcasting method discrimination method characterized in that 3 to 7 individuals. According to claim 1, The output unit; A third flip-flop that delays and outputs an output signal of the detector according to the master clock signal; The pulse signal is reset according to the horizontal synchronization signal separated by the synchronization signal separation unit, and receives a power supply voltage as the first and second inputs to generate a pulse signal corresponding to the rising edge of the output signal of the third flip-flop. A fourth flip-flop; An inverter for inverting the burst gate pulse signal generated by the pulse generator; And And a fifth flip flop for outputting the output signal of the fourth flip flop as a broadcast mode determination signal in response to the output signal of the inverter. Separating the horizontal synchronizing signal from the composite video signal; A second step of generating a burst gate pulse signal having a section width of the composite video signal by counting a master clock signal during a section of the horizontal synchronization signal separated in the first step; A third step of extracting and amplifying the color burst signal from the composite video signal according to the burst gate pulse signal generated in the second step; A fourth step of counting and outputting a set number range of the color burst signal extracted and amplified in the third step; A fifth step of counting the master clock signal during a period in which the preset number range of the color burst signal is counted in the fourth step, and comparing the count value with a set value; And And a sixth step of determining a broadcasting method using a color carrier signal of 3.58 MHz or 4.43 MHz according to the comparison result in the fifth step.