KR19980041327A - Adaptive Blank Signal Generator of PDTV - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adaptive blank signal generation of a PDTV which effectively generates a video blank signal required for setting vertical and horizontal positions of a sub-screen in a main screen in a PDP television having a PIP function. According to an aspect of the present invention, there is provided a display apparatus comprising: synchronization selecting means for selecting a horizontal synchronization signal and a vertical synchronization signal detected from an input image for a main screen among at least two input images in response to a switching control signal from the outside based on user operation; A mode determination block that determines a mode of the input image for the main screen based on the selected horizontal and vertical synchronization signals; A clock generation block for generating a clock signal of several MHz by varying the count value of the horizontal synchronization signal detected in the main picture input image in response to the mode determination signal; Based on the combination of the mode discrimination signal, the vertical position signal from the outside, and the horizontal and vertical synchronizing signals detected in the input image for the main screen, the predetermined blanking interval of the predetermined active section among the effective active line sections in the detected vertical synchronizing signal is A vertical blank selection block for selecting to generate a vertical blanking signal; First inverting means for phase inverting the generated vertical blanking signal; Based on the mode discrimination signal, the clock signal from the clock generation block, the vertical position signal from the outside, and the combination of the horizontal and vertical sync signals detected in the main image input image, the active clock section in the detected horizontal sync signal A horizontal blank selection block which selects a predetermined predetermined clock section and generates a horizontal blank signal; Second inverting means for phase inverting the generated horizontal blanking signal; And based on the selection control signal, the vertical position and the horizontal position signal from the outside based on the user's operation, respectively, the generated vertical blank signal, the inverted vertical blank signal, the generated horizontal blank signal and the inverted horizontal blank signal are selected. And a blank combination block for generating a blank signal of the main picture input image.

Description

Adaptive Blank Signal Generator of PDTV

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for generating an image blank signal required for implementing a picture in picture (PIP) screen in a flat panel display device. More particularly, the present invention relates to a plasma display panel (hereinafter, referred to as PDP). An apparatus for adaptive blank signal generation of a PDP television suitable for generating a video blank signal for setting the vertical and horizontal positions of a PIP picture to be inserted on a main screen.

Recently, the development of technology to replace CRT, which is the main target operation of display devices requiring large size and high operating voltage, is being actively conducted everywhere. As a substitute technology of such CRT, it is possible to reduce the thickness and realize high image quality. There are active display elements such as EL, LED, PDP, and passive display elements such as LCD and ECD. The present invention is an improvement of the PDP display device, which is one of the active elements, that is, a sub-screen at a predetermined position in the main screen. This is related to the generation of a video blank signal which is required when the inserted PIP function is employed in a PDP television.

SUMMARY OF THE INVENTION An object of the present invention is to provide an adaptive blank signal generator of PDTV which can effectively generate a video blank signal required to set the vertical and horizontal positions of the sub picture in the main picture in a PDP television having a PIP function. have.

In order to achieve the above object, the present invention is a device for generating a video blank signal for setting the position of the sub-screen video included in the main screen in a PDP television having a PIP function, from the outside based on user operation A synchronization selecting means for selecting a horizontal synchronizing signal and a vertical synchronizing signal detected from the main image input image among at least two input images in response to a switching control signal of? A mode determination block for determining a mode of the main screen input image based on the selected horizontal and vertical synchronization signals provided from the synchronization selection means; A clock generation block generating a clock signal of several MHz by varying a count value of the horizontal synchronization signal detected in the main screen input image in response to the mode determination signal; Based on the combination of the mode discrimination signal, the vertical position signal from the outside, and the horizontal and vertical synchronizing signals detected in the main image input image, a predetermined section of the effective active line sections in the detected vertical synchronizing signal is preset. A vertical blank selection block that selects a vertical blanking interval to generate a vertical blanking signal; First inverting means for phase inverting the generated vertical blanking signal provided from the vertical blank selection block; An active clock section within the detected horizontal synchronization signal based on a combination of the mode determination signal, the generated clock signal, a vertical position signal from the outside, and the horizontal and vertical synchronization signals detected in the main image input image. A horizontal blank selection block that selects a predetermined predetermined clock period and generates a horizontal blank signal; Second inverting means for phase inverting the generated horizontal blanking signal provided from the horizontal blank selection block; And the generated vertical blank signal, the inverted vertical blank signal, the generated horizontal blank signal and the inverted horizontal blank signal, respectively, based on a selection control signal from the outside based on a user operation, the vertical position and horizontal position signals. By selectively combining the present invention, there is provided an apparatus for adaptive blank signal generation of PDTV comprising a blank combination block for generating a blank signal of the main picture input image.

1 is a block diagram of a typical PDP image processing system suitable for applying an adaptive blank signal generator of PDTV according to the present invention.

2 is a block diagram of an adaptive blank signal generator of PDTV according to a preferred embodiment of the present invention.

3 is a waveform diagram illustrating a process of generating vertical and horizontal blank signals according to the present invention when the input image is an NTSC image;

4 is an output combination waveform diagram of a vertical and horizontal blank signal optionally generated in accordance with the present invention.

* Description of the symbols for the main parts of the drawings *

100,300: image processing block 120,320: A / D conversion block

140,340: memory block 200: blank generation block

202: multiplexer 204: mode decision block

206: clock generation block 208: vertical blank selection block

210: horizontal blank selection block 212: blank combination block

BF1, BF2: Buffer INT1, INT2: Inverter

The above and other objects and various 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.

First, as a video signal input to a PDP television for a PIP type display, for example, a broadcast video signal, a PC video signal, and a playback video from a VCR received through a channel different from the video channel displayed on the main screen. Signals and the like.

In the present invention, for convenience of explanation and improvement, it is assumed that an NTSC broadcast video signal or a PC video signal is input as a main screen or sub-screen video signal. In this case, the conventional NTSC video signal has an interlaced scanning method in which one frame of 525 lines is composed of an odd field and an even field, whereas a PC video signal is composed of a sequential scanning method (noninterlacing method) have.

As an example, the broadcast video signal of the interlace method (eg, NTSC method), which is one of modes to be discriminated in the present invention, has a specification as shown in Table 1 below.

[Figure 1]

Characteristic Field Aether Field Even Field Total number of lines 1H-262.5H 262.5H-525H Active line 22H-263H 284H-525H Valid data lines 23H-262H 285H-524H Blanking section 23H-142H 285H-404H

In addition, another mode to be discriminated by the present invention, a non-interlaced PC video signal, for example, a VGA video PC signal has a specification as shown in Table 2 below.

[Table 2]

Characteristic shock mode Vertical frequency (60 MHz) Vertical frequency (70 MHz) Total number of lines 525H 449H Active line 45H-524H 45H-444H Blanking section 45H-284H 45H-244H

In other words, the NTSC video signal is configured in units of fields, and the PC video signal is configured in units of frames. In the present invention, the mode of the input image is determined using such a characteristic, and is adaptive (or selective) according to the determined mode. To generate an image blank signal.

1 is a block diagram of a typical PDP image processing system suitable for applying the improved blank signal generator of PDTV according to the present invention.

As shown in the figure, a typical PDP image processing system includes a first image processing block 100, a first A / D conversion block 120, a first memory block 140, a blank generation block 200, an address. The generation block 220, the second image processing block 300, the second A / D conversion block 320, and the second memory block 340 are included.

Referring to FIG. 1, the first and second image processing blocks 100 and 300 perform predetermined signal processing on the input image signal, that is, signal processing such as noise removal, level amplification, and gain compensation. The horizontal sync signal and the vertical sync signal are detected. As the input image input to each of the image processing blocks 100 and 300, there are a television video signal (for example, an NTSC video signal), a PC video signal, a playback video in a VCR, and the like.

At this time, the video signal (eg, NTSC video, PC video, etc.) output from the first image processing block 100 is provided to the first A / D conversion block 120 through the line L11, The detected horizontal synchronizing signal H1 and the vertical synchronizing signal V1 are provided to the blank generating block 200 which will be described later.

Similarly, the video signal (eg, PC video, NTSC video, etc.) finally output from the second image processing block 300 is provided to the second A / D conversion block 320 via the line L12, and the input video The detected horizontal synchronizing signal H2 and the vertical synchronizing signal V2 are provided to the blank generation block 200 which will be described later.

On the other hand, the blank generating block 200 is a part directly related to the present invention, and in response to the selection control signal SEL 0 provided from the controller not shown based on the user's operation (selection), The horizontal and vertical synchronization signals H1 and V1 provided by the first image processing block 100 are selected as the synchronization signals of the main screen image, or the horizontal and vertical synchronization signals H2 and H2 provided by the second image processing block 200. V2) is selected as a synchronization signal of the main picture image. Here, the selection of H1, V1 as the main screen synchronization signal means that the video signal (for example, NTSC video, PC video, playback video, etc.) input to the first video processing block 100 is selected as the main screen video. When H2 and V2 are selected as the main screen synchronization signal, the video signal input to the second image processing block 200 (for example, NTSC video, PC video, playback video, etc.) is used for the main screen. It means that the image.

Next, when the main screen synchronization signal is selected according to the selection control signal SEL 0, the blank selection block 200 generates an image blank signal based on the selected horizontal and vertical synchronization signals for the main screen, where the generation is performed. The image blank signal is output on the line L13 and selectively output on the line L14 or the line L15.

That is, the blank selection block 200 generates an image blank signal based on the horizontal and vertical synchronization signals H1 and V1 when the image of the first image processing block 100 is selected as the main screen image. The generated image blank signal is provided to the address generation block 220 and the first A / D conversion block 120 through lines L13 and L14, respectively.

In addition, the blank selection block 200 generates an image blank signal based on horizontal and vertical synchronization signals H2 and V2 when an image of the second image processing block 200 is selected as the main screen image. The generated image blank signal is provided to the address generation block 220 and the first A / D conversion block 320 through lines L13 and L15, respectively.

Meanwhile, the first and second A / D conversion blocks 120 and 320 are predetermined for each of the image signals for the main picture and the sub picture (or the sub picture and the main picture) provided through the lines L11 and L12, respectively. By sampling at each sampling frequency and converting them into digital signals, the first A / D conversion block 120 selects the video signal on the line L11 as the main picture image (in this case, the output video signal on the line L12 is the subpicture picture). The output image signal on the line L11 and the image blank signal on the line L14 are converted into digital signals and provided to the first memory block 140, and the second A / D conversion block 320 is provided on the image on the line L12. When the signal is selected as the main screen image (in this case, the output video signal on the line L11 becomes the sub-screen image), the second memory block converts the output video signal on the line L12 and the image blank signal on the line L15 into digital signals. To 340 The ball.

On the other hand, the first and second memories 140 and 340 respectively store the main screen image data and the sub-screen image data (or the sub-screen image data and the sub-screen image data), respectively. The image data for the screen or the sub-screen and the image blank signal generated according to the present invention are read out according to the read address signal provided from the address generation block 220 to be described later and provided to the display side (not shown).

That is, the address generation block 220 generates a read address signal for reading data based on the blank signal provided by the blank generation block 200 described above through the line L13, and the read address signal generated here is the line L16. And through the line L17 to the first memory block 140 and the second memory block 340, respectively.

Therefore, when the PIP screen is selected by the user, the main screen image data is read in the main screen synchronization signal section according to the read address signal from the address generation block 220, and the blanking of the main screen synchronization signal is performed. In the section, sub-picture image data will be read.

FIG. 2 shows a detailed block diagram of the blank generating block 200 shown in FIG. 1 and shows a block diagram of an apparatus for adaptive blank signal generation of a PDTV according to a preferred embodiment of the present invention.

As shown in the figure, the adaptive blank signal generator of the present invention includes a multiplexer (MUX) 202, a mode determination block 204, a clock generation block 206, a vertical blank selection block 208, and a horizontal blank. The selection block 210 includes two buffers BF1 and BF2, two inverters INT1 and INT2, and a blank combination block 212.

Referring to FIG. 2, the multiplexer 202 is a kind of a switch, and based on a selection control signal SEL 1 selected according to a user's operation (selection of a main screen from two input images), the multiplexer 202 is a type of switch. One of the horizontal and vertical synchronization signals H1 and V1 provided by the first image processing block 100 and the horizontal and vertical synchronization signals H2 and V2 provided by the second image processing block 300 is selected and output. Connect to lines L21 and L22 respectively.

Here, for convenience of explanation and enhancement of understanding, the horizontal and vertical synchronization signals H1 and V1 are signals detected in an NTSC image, and the horizontal and vertical synchronization signals H2 and V2 are signals detected in a PC image. Assume that the NTSC image is selected as the main screen image according to the user's operation.

Therefore, the selected horizontal and vertical synchronization signals H2 and V2 for the main picture on the lines L21 and L22 are provided to the mode decision block 204, the vertical blank selection block 208, and the horizontal blank selection block 210, which will be described later. In addition, the horizontal synchronization signal H2 on the line L21 is provided to the clock generation block 206.

Next, in the mode determination block 204, the mode of the input video signal is discriminated based on the horizontal and vertical synchronization signals H and V detected in the main picture video provided through the lines L21 and L22. It is discriminated whether it is an interlaced broadcast video signal (ie, NTSC video) or a non-interlaced PC video signal.

That is, the number of horizontal synchronization signals H included in the vertical synchronization signal V has a different value depending on the interlacing method (ie, NTSC video signal) and the non-interlacing method (ie, PC video signal). Mode determination of the input image performed in the mode determination block 204 is performed by counting the number of horizontal sync signals H included in the vertical sync signal V, and the result of counting the number of horizontal sync signals H is obtained. Correspondingly, the high or low level mode determination signal generated on the line L25 is provided to the vertical blank selection block 208 and the horizontal blanking selection block 210 which will be described later. The mode determination signal on line L23 is also provided to clock generation block 206.

In this case, it is assumed that a high level discrimination signal is generated on the line L25 when the input image is an interlaced image (that is, an NTSC video signal), and a low level discrimination signal is generated when the image is a noninterlaced image (PC video signal). Then, a high level mode determination signal will be generated.

Next, the clock generation block 206 may be configured, for example, with PLL logic, to generate a clock signal synchronized with the horizontal synchronizing signal provided through the line L21, where the mode determination block ( The count value is varied according to the mode determination signal provided at 204. That is, when the mode determination signal on the line L23 is high level (that is, the input image is an NTSC video signal), 1600 is counted to generate a clock signal of 25.175 MHz on the line 24, and the mode determination signal on the line L23 is low level. (I.e., when the input image is a PC image signal), the number of 800 is counted to generate a clock signal of 25.175 MHz on the line 24, and the clock signal generated on the line L24 is provided to the horizontal blank selection block 210 described later. .

That is, according to the present invention, a clock signal suitable for an NTSC video signal or a PC video signal is generated by generating a clock signal having a different count value according to a determination result of which image the input video is.

On the other hand, the vertical blank selection block 208 is a vertical position provided from the outside in accordance with the mode determination signal provided by the mode determination block 204 described above through the line L25, the user's screen selection (main screen and sub-screen) operation A vertical blank line is selected based on the signal VP and the horizontal and vertical synchronization signals on the lines L21 and L22 detected in the main picture image, that is, as shown in FIG. 3A as an example when the main picture image is an NTSC image. A vertical blank signal having a blanking section (23H-142H: 120 lines) as shown in Fig. 3B is generated and output among the active line sections (23H-263H: 240 lines) in the same field.

As a specific embodiment of such a vertical blank selection block 208, it has been proposed by the present inventor and has been filed by the Korean Patent Office under the name “vertical blank generator of PDTV”.

At this time, the vertical blank signal as shown in FIG. 3B having the vertical blanking interval generated in the vertical blank selection block 208 is provided to the blank combination block 212 through the buffer BF1 and the line L26 and at the same time the inverter INT1. The signal inverted through < RTI ID = 0.0 >), i. E., Inverted as shown in FIG.

On the other hand, the horizontal blank selection block 210 is horizontally provided from the outside in accordance with the mode determination signal provided in the mode determination block 204 described above through the line L25, the user's screen selection (main screen and sub-screen) operation A horizontal blank line is selected based on the position signal HP and the horizontal and vertical synchronization signals on the lines L21 and L22 detected in the main picture image, that is, when the main picture image is an NTSC image, as shown in FIG. 3E as an example. A horizontal blank signal having a blanking clock period (320 clock) as shown in FIG. 3F is generated and output among the active clock pulse intervals (640 clocks) as shown in FIG.

As a specific embodiment of such a horizontal blank selection block 210, it has been proposed by the present inventors and has been filed by the Korean Patent Office under the name "Horizontal Blank Generator of PDTV".

At this time, the horizontal blank signal as shown in FIG. 3E having the horizontal blanking interval generated in the horizontal blank selection block 208 is provided to the blank combination block 212 through the buffer BF2 and the line L28 and at the same time the inverter INT2. The signal inverted by < RTI ID = 0.0 >), i. E., As shown in FIG.

On the other hand, in the blank combination block 212, the selection control signal SEL 2 provided from the outside based on the user selection operation and the vertical position signal VP provided from the outside based on the screen selection (main screen and sub-screen) operations. And the vertical and horizontal blank signals generated by the vertical blank selection block 208 and the horizontal blank selection block 210 to generate the final image blank signal, based on the horizontal position signal HP. The image blank signal is provided to the address generation block 220 of FIG. 1 via the line L13.

That is, two vertical blank signals, as shown in FIGS. 3B and 3C, are input through lines L26 and L27, and two, as shown in FIGS. 3F and 3G, through lines L28 and L29. Assuming two horizontal blank signals are input, the output image blank signal in the blank combination block 212 combined based on the selection control signal SEL 2 from the outside is divided into four, as shown in FIG. It will be one of the signals.

For example, based on the selection control signal SEL 2 from the outside, if the vertical blank signal (Fig. 3B) on the line L26 and the horizontal blank signal (Fig. 3F) on the line L28 are selected, on line L13, Fig. 4A. An image blank signal is output, as shown in Fig. 3, and when the vertical blank signal (Fig. 3B) on line L26 and the horizontal blank signal (Fig. 3G) on line L29 are selected, on line L13, as shown in Fig. 4B, An image blank signal is output, and if a vertical blank signal (FIG. 3C) on line L27 and a horizontal blank signal (FIG. 3F) on line L28 are selected, an image blank signal, as shown in FIG. 4C, is output on line L13. If the vertical blank signal (Fig. 3C) on line L27 and the horizontal blank signal (Fig. 3G) on line L29 are selected, on line L13 an image blank signal, as shown in Fig. 4D, will be output.

Accordingly, in the address generation block 220 of FIG. 1, the first memory block 140 is generated by generating a read address signal for reading data based on the image blank signal provided by the blank generation block 200 described above through the line L13. ) And the second memory block 340, respectively.

Therefore, when the PIP screen is selected by the user, the main screen image data is read in the main screen synchronization signal section according to the read address signal from the address generation block 220, and the blanking of the main screen synchronization signal is performed. In the section, sub-picture image data will be read.

As described above, according to the present invention, when a PIP screen is implemented on a PDP television, a user can arbitrarily select a main screen and a sub-screen displayed in the form of being inserted into the main screen, and are inserted into the main screen. The image blank signal required to set the position of the displayed sub-screen can be effectively generated, enabling the implementation of an effective PIP function in a PDP television.

Claims (11)

An apparatus for generating a video blank signal for setting the position of a sub-screen video included in a main screen in a PDP television having a PIP function, Synchronization selecting means for selecting a horizontal synchronizing signal and a vertical synchronizing signal detected in the main image input image among at least two input images in response to a switching control signal from the outside based on a user operation; A mode determination block for determining a mode of the main screen input image based on the selected horizontal and vertical synchronization signals provided from the synchronization selection means; A clock generation block generating a clock signal of several MHz by varying a count value of the horizontal synchronization signal detected in the main screen input image in response to the mode determination signal; Based on the combination of the mode discrimination signal, the vertical position signal from the outside, and the horizontal and vertical synchronizing signals detected in the main image input image, a predetermined section of the effective active line sections in the detected vertical synchronizing signal is preset. A vertical blank selection block that selects a vertical blanking interval to generate a vertical blanking signal; First inverting means for phase inverting the generated vertical blanking signal provided from the vertical blank selection block; An active clock section within the detected horizontal synchronization signal based on a combination of the mode determination signal, the generated clock signal, a vertical position signal from the outside, and the horizontal and vertical synchronization signals detected in the main image input image. A horizontal blank selection block that selects a predetermined predetermined clock period and generates a horizontal blank signal; Second inverting means for phase inverting the generated horizontal blanking signal provided from the horizontal blank selection block; And The generated vertical blank signal, the inverted vertical blank signal, the generated horizontal blank signal and the inverted horizontal blank signal, respectively, on the basis of the selection control signal from the outside based on user operation, the vertical position and the horizontal position signal. By selectively combining, a blank combining block for generating a blank signal of the input image for the main picture Adaptive blank signal generator of PDTV. The apparatus of claim 1, wherein each input video is one of an NTSC video signal and a PC video signal. The apparatus of claim 1, wherein the clock generation block comprises PLL logic. The method of claim 1, wherein the mode determination block determines whether the input image is an interlaced image or a noninterlaced image by counting the number of horizontal sync signals in the detected vertical sync signal. Adaptive blank signal generator of PDTV. The vertical blank selection block according to claim 1, 2, or 3, wherein the vertical blank selection block is set in the vertical synchronization signal of the odd and even fields detected in the input NTSC image when the selected main screen input image is an NTSC image. An adaptive blank signal generator of PDTV, characterized in that each of the preceding 120H lines of each effective active line section is selected as the vertical blanking section of the odd and even fields. 6. The apparatus of claim 5, wherein the PC image is a VGA mode image having a vertical frequency of 60 MHz or 70 MHz. The vertical blank selection block of claim 5, wherein the vertical blank selection block includes a 240H line preceding a valid active line section in a vertical synchronization signal detected by the input PC image when the input image is a PC image having a vertical frequency of 60 MHz. Adaptive blank signal generator of the PDTV, characterized in that for selecting the vertical blanking period. The vertical blank selection block of claim 5, wherein the vertical blank selection block is configured to select a preceding 200H line in an effective active line section in a vertical synchronization signal detected by the input PC image when the input image is a PC image having a vertical frequency of 70 MHz. Adaptive blank signal generator of the PDTV, characterized in that for selecting the vertical blanking period. The vertical blank selection block of claim 1, 2, or 3, wherein the vertical blank selection block has 320 clocks when the active clock interval of the detected horizontal synchronization signal is 640 clocks. An adaptive blank signal generator of PDTV. 4. The method of claim 1, 2 or 3, wherein the blank combination block is obtained through a cross combination between the generated vertical blank signal and the inverted vertical blank signal and the generated horizontal blank signal and the inverted horizontal blank signal. And an output of at least one of the four combinations as the image blank signal. 4. The apparatus of claim 1, 2 or 3, wherein the first and second inverting means each comprise an inverter.