KR0174929B1 - Apparatus for processing the video signal in plasma display panel - Google Patents

Abstract

The present invention relates to an image processing apparatus in a PDP, wherein a composite video signal of a desired channel is tuned in a tuner and provided to an image processor and a pulse signal generator, respectively, and whether or not a video signal is present is determined by the image signal discriminator. If there is an image signal, the sync detector detects a vertical sync signal and a horizontal sync signal, and then generates a pulse signal for selecting an effective video signal through a first counter, a second counter, and an AND gate. In the case of the non-signal, the PDP generates a vertical synchronization signal and a horizontal synchronization signal, and generates a pulse signal for selecting the first predetermined number set through the first counter, the second counter, and the AND gate. If the composite video signal tuned by the tuner is no signal by being processed by the processing unit and then displayed on the PDP, Since the predetermined predetermined period is selected and image processed, it is possible to prevent unnecessary waste of the memory and to prevent malfunction on the PDP circuit due to no signal.

Description

Image processing device in PD

1 is a schematic block diagram of an exemplary image processing apparatus according to the present invention.

2 is a detailed view of the pulse signal generator 100 of FIG.

3 is a diagram showing a pulse signal for image processing according to the present invention;

4 is a detail of part A shown in FIG.

* Explanation of symbols for main parts of the drawings

50: tuner 100: pulse signal generator

105: image signal discrimination unit 110: switching unit

115: synchronization detection unit 120: synchronization generation unit

125: first counter 130: second counter

135: AND gate 150: image processing unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PDP (PLASMA DISPLAY PANEL; hereinafter abbreviated as PDP), and more particularly, to an image processing apparatus in a PDP in which a video signal can be selected in the absence of a signal.

In recent years, many studies on so-called flat display devices having large display areas and small volumes have been continuously conducted in various fields related thereto.

The flat display device includes an active element such as an electroluminescent NCE, a light emitting diode, a PDP, a liquid crystal display, an electrochromic display, and an electrochromic display. There is a passive element such as the present invention, and the present invention relates to a PDP which is substantially one of the active elements.

On the other hand, when the user selects a channel where there is no broadcast signal (hereinafter referred to as a no signal), there is a problem that a malfunction occurs on the PDP circuit due to waste of memory and noise because the sampling section is not set.

Accordingly, an object of the present invention is to provide an image processing apparatus in a PDP capable of setting a sampling period by generating a vertical synchronization signal and a horizontal synchronization signal at the time of no signal. There is this.

In order to achieve the above object, the present invention provides a PDP apparatus for processing a composite video signal from a broadcast station tuned through a tuner and then displaying the composite video signal through a tuner, wherein the vertical sync and horizontal sync signals of the composite video signal through the tuner are displayed. Video signal discrimination means for determining the presence or absence of a signal and generating a control signal corresponding thereto, switching means for generating a first switching signal and a second switching signal based on the control signal from the video signal discrimination means, and the switching means. The synchronous detection means for detecting the vertical synchronous signal and the horizontal synchronous signal in the composite video signal based on the first switching signal from the vertical synchronous signal and the horizontal synchronous signal based on the second switching signal from the switching means. Number generated by the synchronization generating means, the synchronization detecting means and the synchronization generating means A first pulse generating means for inputting a synchronous signal and a horizontal synchronous signal to generate a high level pulse signal from a blanking interval to the falling edge of the vertical synchronous signal; and a vertical synchronous generated by the synchronous detection means and the synchronous generating means. The second pulse generating means for generating a high level pulse signal from the rising edge of the vertical synchronizing signal to the first predetermined number by inputting the signal and the horizontal synchronizing signal and the pulse signal from the first pulse generating means. Logic means for generating a pulse signal for selecting a sampling interval by inputting a pulse signal from the second pulse generating means to the other input terminal, and through the tuner based on the pulse signal from the logic means. An image processing apparatus in a PDP, characterized by comprising image processing means for image processing a composite image signal. It provides.

Other objects and advantages of the present invention will become more apparent from the preferred embodiments of the present invention described below with reference to the accompanying drawings by those skilled in the art.

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

FIG. 1 is a schematic block diagram of a typical image processing apparatus according to the present invention, and includes a tuner 50, a pulse signal generator 100, and an image processor 150.

Referring to FIG. 1, the tuner 50 tunes a corresponding composite video signal based on a channel selection signal from a microcomputer, which is not shown among the composite video signals transmitted from a broadcasting station, and outputs a pulse signal generator ( 100 checks the composite video signal tuned by the tuner 50 and generates a pulse signal for selecting a sampling section according to the presence or absence of the video signal, and the image processor 150 generates a pulse signal from the pulse signal generator 100. The composite image signal tuned by the tuner 50 is processed based on the signal.

2 is a detailed view of the pulse signal generator 100 of FIG. 1, and as can be seen from the same drawing, the pulse signal generator 100 includes an image signal discriminator 105 and a switch 110. And a synchronization detector 115, a synchronization generator 120, a first counter 125, a second counter 130, and an AND gate 135.

In FIG. 2, the image signal discrimination unit 105 checks the existence of the vertical synchronizing signal and the horizontal synchronizing signal among the composite image signals tuned by the tuner 50, and switches if the vertical synchronizing signal and the horizontal synchronizing signal exist. Generates a control signal for switching between the fixed terminal (a) and the variable terminal (b) of the unit 110, and if there is no vertical synchronous signal and horizontal synchronous signal, the fixed terminal (a) and the variable of the switching unit 110 A control signal for switching terminal b is generated.

The switching unit 110 switches the fixed terminal a and the variable terminals b and c based on the control signal from the image signal discriminating unit 105, and the synchronization signal detecting unit 115 switches the switching unit 110. The fixed terminal (a) and the variable terminal (b) of the) is detected by switching the vertical synchronization signal and the horizontal synchronization signal from the composite video signal provided to provide to the first counter 1 (25) and the second counter 130, The synchronization generator 120 generates a vertical synchronization signal and a horizontal synchronization signal when the fixed terminal a and the variable terminal c of the switching unit 110 are switched, thereby generating the first counter 125 and the second counter 130. To provide.

In addition, the first counter 110 counts the number of horizontal synchronization signals among the vertical synchronization signals provided from the synchronization detector 115 and the synchronization generator 120 to vertically pulse the high level pulse signal after the blanking period of the vertical synchronization signal. The falling edge of the synchronization signal (FALLING EDGE) is generated, the second counter 130 is a first predetermined number set from the rising edge of the vertical synchronization signal provided from the synchronization detector 115 and the synchronization generator 120, for example For example, a high level pulse signal is generated up to the number 240H of horizontal synchronization signals to be sampled.

In FIG. 2, the AND gate 135 inputs a pulse signal generated from the first counter 125 to one input terminal, and inputs a logical multiplication by inputting the pulse signal generated from the second counter 130 to the other input terminal. In addition, a pulse signal for selecting a sampling interval is generated, and the image processor 150 performs image processing on the composite image signal tuned by the tuner 50 based on the pulse signal provided from the pulse signal generator 100 and then passes the PDP. Display.

The operation of the image processing apparatus in the PDP composed of the above-described members will be described in more detail with reference to the first, second, third, and fourth drawings.

First, a composite video signal transmitted from a broadcasting station is received through an antenna, and the composite video signal of a desired channel is tuned by the tuner 50 and then provided to the image processor 150 and the pulse signal generator 100.

Next, the video signal discriminating unit 105 in the pulse signal generating unit 100 checks whether a vertical synchronizing signal and a horizontal synchronizing signal exist in the composite image signal provided from the tuner 50, and then the vertical synchronizing signal and the horizontal synchronizing signal. If a signal is present, a control signal for switching between the fixed terminal a and the variable terminal c of the switching unit 110 is generated. If there is no vertical synchronization signal and the horizontal synchronization signal, the fixed terminal of the switching unit 110 is present. A control signal for switching between (a) and variable terminal (c) is generated.

Here, the fixed terminal a and the variable terminal c of the switching unit 110 are switched based on the control signal for switching the fixed terminal a and the variable terminal c from the image signal discriminator 105. Then, the vertical synchronizing signal and the horizontal synchronizing signal are detected by the synchronization detecting unit 115 among the composite image signals tuned by the tuner 50 and provided to the first counter 125 and the second counter 130, respectively.

Meanwhile, when the fixed terminal a and the variable terminal c of the switching unit 110 are switched based on the control signal for switching the fixed terminal a and the variable terminal c from the image signal discriminating unit 105. The vertical synchronizing signal and the horizontal synchronizing signal are generated from the synchronizing generator 120 and provided to the first counter 125 and the second counter 130, respectively.

Next, a case in which a video signal exists in a composite video signal and a case in which a video signal does not exist in the composite video signal will be described.

First, when a video signal exists in the composite video signal, the vertical sync signal and the horizontal sync signal detected by the sync detector 115 are provided to the first counter 125 and the second counter 130, and the first counter. The counting unit 125 counts the number of horizontal synchronizing signals from the rising edges of the vertical synchronizing signals detected by the synchronizing detection unit 115, and detects the synchronizing detecting unit 115 after the blanking period of the vertical synchronizing signals detected by the synchronizing detection unit 115. A pulse signal of high level is generated up to the falling edge of the vertical synchronization signal.

In addition, the second counter 130 generates a high level pulse signal from the rising edge of the vertical synchronization signal detected by the synchronization detector 115 to set the first predetermined number, for example, the number of horizontal synchronization signals to be sampled ( Up to 240H).

Next, the pulse signal generated from the first counter 125 is input to one input terminal of the AND gate 135, and the pulse signal generated from the second counter 130 is input to the other input terminal of the AND gate 135. Then, the result is logical multiplication, and a pulse signal for selecting an effective video signal excluding the blanking section is generated.

Therefore, the effective video signal of the composite video signal tuned by the tuner 50 based on the pulse signal generated from the output terminal of the AND gate 135 is processed by the image processor 150 and then displayed on the PDP.

Second, when there is no signal among the composite video signals, the vertical synchronization signal (a) of FIG. 3 and the horizontal synchronization signal (b) of FIG. The number of horizontal synchronization signals is counted from the rising edge of the vertical synchronization signal generated by the synchronization generator 120 to generate a high level pulse signal after the blanking period, thereby generating the vertical synchronization signal generated by the synchronization generator 120. Occurs up to the falling edge (c) of FIG.

Here, the details of the portion A (vertical synchronous signal a and horizontal synchronous signal b) shown in FIG. 3 are as shown to those skilled in the art. as shown in b).

On the other hand, the second counter 130 generates a high level pulse signal from the rising edge of the vertical synchronization signal generated by the synchronization generator 125 to set the first predetermined number, for example, the number of horizontal synchronization signals to be sampled. A pulse signal of high level is generated until (d) in FIG.

Next, the pulse signal (FIG. 3C) generated from the first counter 125 is input to one input terminal of the AND gate 135, and the pulse signal generated from the second counter 130 (FIG. (d) is input to the other input terminal of the AND gate 135 and then logically multiplied to generate a pulse signal for selecting a common high level pulse signal section.

Accordingly, the signal-free tuned by the tuner 50 based on the pulse signal generated from the output terminal of the AND gate 135 is image-processed by the image processor 150 and then displayed on the PDP.

As described above, the composite video signal of the desired channel is tuned by the tuner 50, tuned by the image processor 150, and provided to the pulse signal generator 100 by the image processor 150, respectively, and the image signal discrimination unit. In step 105, the presence or absence of the video signal is determined, and when the video signal is present, the vertical synchronization signal and the horizontal synchronization signal are detected by the synchronization detector 115, and then the first counter 125 and the second counter 130 and A pulse signal for selecting an effective video signal is generated through the AND gate 135, is processed by the image processing unit 150, and then displayed on the PDP. If there is no signal, the vertical synchronization signal and horizontal synchronization are synchronized from the synchronization generating unit 120. A signal is generated to generate a pulse signal for selecting the first predetermined number set through the first counter 125, the second counter 130, and the AND gate 135, and is processed by the projection processor 150 to be image-processed. Is displayed.

Therefore, according to the present invention, when the composite video signal tuned by the tuner 50 is no signal, the predetermined predetermined section is selected and image processed, thereby not only preventing waste of memory but also malfunctioning on the PDP circuit due to no signal. There is an effect that can prevent.

Claims (5)

A PDP apparatus for processing a composite video signal from a broadcast station tuned through a tuner 50 and then displaying the composite video signal on a PDP, wherein the presence or absence of a vertical sync signal and a horizontal sync signal of the composite video signal through the tuner 50 is determined. Video signal discrimination means (105) for generating a control signal corresponding thereto; Switching means (110) for generating a first switch signal and a second switching signal based on the control signal from the video signal discrimination means (105); The synchronization detecting means (115) for detecting a vertical synchronization signal and a horizontal synchronization signal in the composite video signal based on a first switching signal from the switching means (110); The synchronization generating means (120) for generating a vertical synchronization signal and a horizontal synchronization signal based on the second switching signal from the switching means (110); A first signal for generating a high level pulse signal from a blanking period to a falling edge of the vertical synchronization signal by inputting a vertical synchronization signal and a horizontal synchronization signal generated by the synchronization detecting means 115 and the synchronization generating means 120; Pulse generating means 125; Inputting the vertical synchronization signal and the horizontal synchronization signal generated by the synchronization detecting means 115 and the synchronization generating means 120 to generate a high level pulse signal from the rising edge of the vertical synchronization signal to the first predetermined number. Second pulse generating means (130); The pulse signal from the first pulse generating means 125 is input to one input terminal, and the pulse signal from the second pulse generating means 130 is input to the other input terminal to generate a pulse signal for selecting a sampling section. Logic means 135; And image processing means (150) for image processing the composite video signal through the tuner (50) based on the pulse signal from the logic means (135). The image processing apparatus according to claim 1, wherein each pulse generating means is a counter. The image processing apparatus of claim 1, wherein the first predetermined number is the number of horizontal synchronization signals with respect to an image signal to be sampled. The image processing apparatus of claim 1, wherein each of the logic means is an AND gate. 4. The image processing apparatus of claim 1 or 3, wherein the first predetermined number is the number of horizontal synchronization signals of a 240H line.