KR100220695B1 - Apparatus for adaptively generating vertical blank of video signals in pdp tv - Google Patents

Abstract

The present invention provides an adaptation for a PDP television that can effectively generate a vertical blank signal suitable for setting the vertical position of a video screen when displaying on a panel an image mode having at least fewer lines than a display panel. The present invention relates to a vertical blank generating apparatus. To this end, the present invention relates to a vertical blank generating device, and generates a selection pulse by determining a mode for each size of an input image based on horizontal and vertical synchronization signals detected from an input image. A mode discrimination and pulse shaping block for generating a field discrimination signal and matching the polarity of the vertical frequency detected in the input image equally; A shift register generating a new vertical synchronizing signal by shifting the detected vertical synchronizing signal by a predetermined 42H line based on the detected horizontal synchronizing signal; A buffer block for buffering the generated selection pulse, the field separation signal, the detected horizontal synchronization signal and the new vertical synchronization signal for timing synchronization between the signals; A first counter for generating a blank pulse of 40H lines between 445H and 35H lines for each field in the generated new vertical sync intervals 43H to 449H, respectively, based on the detected horizontal sync signal and the new vertical sync signal; In response to the generated selection pulse provided from the buffer block, the detected horizontal sync signal and the new vertical sync signal are inputted to count the active sections in the new vertical sync section, and 45H-45H- A second counter for detecting an active section between lines 444H; Logic means for generating a horizontal sync pulse in the detected active section through a logical product operation between the detected horizontal sync signal and the detected active section provided from the second counter; A frequency multiplier for frequency-dividing horizontal sync pulses in the active section provided by the logic means to generate horizontal sync pulses divided by N times to generate a vertical section having an odd field of 200H odd lines in the active section; An inverter for inverting the N-fold divided horizontal sync pulses to generate a vertical section having horizontal sync pulses for an odd field of even lines of 200H in an active period; And a vertical blank signal for an odd field made by combining a vertical section having a blank pulse provided from the first counter and a horizontal sync pulse for an odd field of odd lines in response to the generated selection pulse and the generated field separation signal. And a vertical blank selection block that alternately generates a vertical blank signal for an even field made by combining a blank pulse provided at one counter and a vertical section having horizontal sync pulses for an odd field of even lines.

Description

Adaptive Vertical Blank Generator in PDTV

The present invention relates to an apparatus for generating a vertical blank signal required for realizing a screen of an image in a flat panel display device, and more particularly, to an image having a different number of lines in a plasma display panel (hereinafter referred to as PDP). An adaptive vertical blank generator in a PDP television suitable for generating a vertical blank signal for acceptance of a mode.

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, ECD, etc. The present invention relates to the improvement of PDP display which is one of the active elements.

On the other hand, as a video signal input to a PDP television for display, for example, a broadcast video signal received via a channel, a PC video signal (for example, NTSC video), and the like can be given. Here, the NTSC video has a 525H section, whereas the PC video signal has various modes, that is, the 640x400 mode (VGA), the 640x480 mode (SVGA), etc., each having the following table and video specifications.

[graph]

In other words, as can be seen from the above chart, the VGA mode and the SVGA mode are different from each other in the 400H sections (45H-444H) and the 480H sections (45H-524H).

Therefore, as an example, when a panel having a mode of 640 × 480 × 3 (aspect ratio 4: 3) is used as a display panel of a PDP television, there is no problem in SVGA mode image processing of PC images, but image data when processing the VGA mode. Appropriate processing (i.e., vertical position setting of the video screen, etc.) for the 80H line section in which there is no is desired, but the technique for such processing is not known at present.

SUMMARY OF THE INVENTION The present invention has been made in view of the foregoing, and in a PDP television, a vertical blank signal suitable for setting a vertical position of a video screen when displaying on a panel an image mode having at least fewer lines than a display panel is provided. It is an object of the present invention to provide an adaptive vertical blank generator in PDTV that can be effectively generated.

In order to achieve the above object, the present invention provides a vertical blank signal for setting a vertical position necessary for displaying an image having a number of lines smaller than the size of a monitor on a monitor of a PDP television accommodating a broadcast signal and a PC video signal. In the generating device, based on the horizontal and vertical synchronizing signal detected in the input image, to generate a selection pulse by determining the mode by size of the input image, and generates a field separation signal when the input image is the PC image, A mode discrimination and pulse shaping block for equally matching the polarity of the vertical frequency detected in the input image; A shift register generating a new vertical synchronizing signal by shifting the detected vertical synchronizing signal by a predetermined 42H line based on the detected horizontal synchronizing signal; A buffer block for buffering the generated selection pulse, field separation signal, detected horizontal synchronization signal and new vertical synchronization signal for timing synchronization between each signal; A blank of 40H lines between 445H and 35H lines for each field in the generated new vertical sync intervals 43H to 449H based on the detected horizontal sync signal and the new vertical sync signal provided in the buffer block. First counters for generating pulses respectively; In response to the generated selection pulse provided from the buffer block, the detected horizontal synchronization signal and the new vertical synchronization signal are inputted to count the active periods in the new vertical synchronization period, and each vertical of 43H-449H lines. A second counter for detecting an active section between 45H-444H lines of the section, respectively; Logic means for generating a horizontal synchronizing pulse in the detected active period through an AND operation between the detected horizontal synchronizing signal and the detected active period provided from the second counter; Frequency-dividing the horizontal synchronizing pulses in the active section provided by the logic means to generate horizontal synchronizing pulses divided by N times, thereby generating a vertical section having an odd field of 200H odd lines in the active section. Frequency multiplier; An inverter for inverting the N-times divided horizontal sync pulses to generate a vertical section having horizontal sync pulses for an odd field of even lines of 200H in the active section; And in response to the generated selection pulse and the generated field division signal, a blank pulse provided from the first counter and a vertical section having a horizontal synchronization pulse for an odd field of odd lines. A vertical blank selection block for alternately generating a vertical blank signal for an even field, which is made by combining a blank signal, a blank pulse provided from the first counter, and a vertical section having an even field horizontal synchronization pulse of the even lines. An adaptive vertical blank generator in PDTV is provided.

1 is a block diagram of a typical blank signal generation system suitable for applying an adaptive vertical blank generator in a PDTV according to the present invention.

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

3 is a pulse waveform diagram showing an example of an image mode having a 525H horizontal section in each line and an image mode having a 449H horizontal section in each line.

Fig. 4 is a pulse waveform diagram of each part showing a process of selecting a vertical blanking section required when accommodating an image having a 449H horizontal section in a PDP television capable of displaying a 525H horizontal section per line according to the present invention.

FIG. 5 illustrates an example in which an image having a 444H horizontal section per line is displayed on a panel having a size of 640 × 480 × 3 according to a vertical blank signal generated according to the present invention.

* Explanation of symbols for main parts of the drawings

100: horizontal blank generation block 200: vertical blank generation block

202: Mode determination and pulse shaping block 204: Shift register

206: buffer 208: first counter

210: second counter 212: end gate

214: Frequency multiplier 216: Vertical blank selection block

300: blank combination block 400: address generation block

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, it is assumed that the display panel employed in the PDP television for adoption of the present invention is a panel having a mode of 640 × 480 × 3 having an aspect ratio of 4: 3, and as an input image, an NTSC image having a 525H section for each line, Assume a VGA mode PC image having a 449H section or an SVGA mode PC image having a 525H section per line.

Therefore, when the signal input to the PDP television is NTSC video or SVGA PC video, i.e., when the section (active section) where the actual video data exists for each line is 480H line, the horizontal and vertical generated according to the conventional method. By using the blank signal, a read address for reading the image data stored in the memory will be generated to set the horizontal and vertical positions on the panel.If the input signal is a VGA PC image, that is, the actual image data exists for each line. If the section (active section) is a 400H line, the vertical position of the video screen displayed on the panel will be set according to the vertical address signal generated based on the vertical blank signal adaptively generated according to the present invention.

That is, in the present invention, when a PC image of 640 × 400 mode is input when the size of the monitor is 640 × 480, the remaining area of the monitor remaining after expressing the input image is shown in the lower portion of the monitor as an example. Create a corresponding adaptive vertical blank signal so that it can be concentrated and displayed in the blank area (ie, bottom 80 lines). In this case, not only an adaptive display corresponding to the mode but also a display effect such as a movie screen may be obtained.

1 is a block diagram of a typical blank signal generation system suitable for applying an adaptive vertical blank generator in a PDTV according to the present invention.

As shown in the figure, a typical blank signal generation system includes a horizontal blank generation block 100, a vertical blank generation block 200, a blank combination block 300 and an address generation block 400.

Referring to FIG. 1, the horizontal blank generation block 100 is a horizontal synchronization signal on a line L11 detected from an image (ie, an NTSC image, a VGA mode PC image, or an SVGA mode PC image, etc.) input to a PDP television for display. Based on (H) and the vertical synchronizing signal (V) on the line L13, a horizontal blank signal for setting the horizontal position of the screen displayed on the PDP panel is generated and passed to the next blank combination block 300 through the line L15. to provide.

Next, the vertical blank generation block 200 is a part which is directly related to the present invention and is based on the horizontal synchronization signal H on the line L11 and the vertical synchronization signal V on the line L13. 3A, that is, the input image has an horizontal section of 525H for each line (having an active section of the 480H line, as shown in FIG. 3B) (NTSC image, SVGA mode PC image, as shown in FIG. 3B). 3C, or as an image (VGA mode PC image) having a horizontal section of 449H for each line (having an active section of the 400H line, as shown in FIG. 3D) as shown in FIG. 3C. Based on the determination result, a vertical blank signal corresponding thereto is generated and provided to the next blank combination block 300 through the line L17. In the vertical blank generation block 200 according to the present invention, a detailed operation process of generating a vertical blank signal when the input image is a VGA mode (having an active section of 400H per line) PC image according to the present invention will be described with reference to FIG. 2. It will be described later in detail.

On the other hand, the blank combination block 300 detects according to the present invention provided from the horizontal blank signal provided from the horizontal blank generation block 100 through the line L15 and the vertical blank generation block 200 described through the line L17. The generated vertical blank signal is combined to generate a completed image blank signal, and the generated image blank signal is provided to the next address generation block 400 through the line L19.

Next, in the address generation block 400, on the basis of the image blank signal provided by the blank combination block 300 described above via the line L19, to the frame memory (i.e., the odd field memory and even field memory) not shown. A read address signal for reading stored video data (image data for odd field and image field for even field) is generated.

Therefore, in the frame memory (i.e., odd field memory and even field memory) not shown, each image corresponding to the read address signal from the address generation block 400 described above is used for image display through the PDP panel. The data will be read sequentially.

In addition, a typical NTSC video signal has an interlaced scan method (interlaced method) in which one frame of 525 lines is composed of an odd field (2626H line of odd) and an even field (yield 262.5H line). Is composed of a sequential scanning method (non-interlacing method). Therefore, it is necessary to convert a non-interlaced PC image to an interlace method, and the adaptive vertical blank generator of the present invention performs such image conversion when the PC image is input.

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

As shown in the figure, the adaptive vertical blank generator of the present invention is a mode determination and pulse shaping block 202, a shift register 204, a buffer block 206, a first counter 208, a second counter. 210, end gate 212, frequency multiplier 214, buffer BF, inverter INT, and vertical blank selection block 216.

Referring to FIG. 2, in the mode determination and pulse shaping block 202, the horizontal synchronization signal H detected in the input image provided through the line L11 and the vertical synchronization signal detected in the input image provided through the line L13 ( V) to determine the mode of the input video signal, i.e., whether the input video is an image mode (i.e., NTSC image or SVGA mode PC image) having a horizontal section of 525H (active section of the 480H line) or the input image is of 449H. It determines whether the image mode (VGA mode PC image) has a horizontal section (active section of the 400H line), and generates a high or low level selection pulse SP on the line L21 according to the result of the determination. To the buffer block 206. For example, if the input image is in 640 × 400 mode, a low level selection signal SP is generated on line L21. If the input image is in 640 × 480 mode, a high level selection signal SP is generated on line L21. do.

Meanwhile, if the input image is a PC image of a sequential scanning method (non-interlacing method) by determining the method of the input image, it must be converted to an interlaced scanning method (interlacing method). For this, the mode discrimination and pulse shaping block 202 In the case where the input image is a PC image, as an example, as shown in FIG. 4D, a field division signal (E / O) of high or low level is generated and provided to the buffer block 206 through the line L22. That is, the number of horizontal synchronization signals H included in the vertical synchronization signal V has different values according to the interlace method (i.e., NTSC video signal) and the non-interlace method (i.e., PC video signal). In addition, in the case of a PC image, it has different values according to modes (VGA mode, SVGA mode, etc.), and the mode determination and the method determination of the input image performed in the pulse shaping block 202 are included in the vertical synchronization signal V. This is performed by counting the number of horizontal synchronization signals H to be generated, and a field discrimination signal E / O having a high or low level is generated on the line L22 corresponding to the count result of the horizontal synchronization signals H. The field separation signal E / O may define, for example, an odd field section as a high level and an even field section as a low level.

Further, in the mode discrimination and pulse shaping block 202, when the input video is a non-interlaced PC video, the output of the vertical frequency having different polarities is fixed, that is, the vertical of the PC video signal having a vertical frequency of 60 MHz. The vertical polarity of PC video signal with frequency polarity and vertical frequency of 70 MHz has opposite polarity (+ polarity of vertical frequency of 60 MHz,-polarity of vertical frequency of 70 MHz). In 202, these polarities are kept constant through polarity inversion.

On the other hand, the shift register 204 presets the vertical synchronizing signal V1 provided through the line L24 based on the horizontal synchronizing signal H provided by the mode determination and pulse shaping block 202 described above via the line L23. Shifting by a predetermined pulse period, i.e., shifting the 42H line, for example, the vertical blanking signal V1 as shown in FIG. 4B, as shown in FIG. 4C, the vertical blank sections 43H and 44H of the 2H line shifted by 42H. Generates a new vertical synchronizing signal V2 with < RTI ID = 0.0 > 1, < / RTI >

At this time, the buffer block 206 buffers each signal for timing synchronization between the signals generated on the lines L21, L22, L23, and L25, and the buffer block 206 selects a pulse SP on the line L26. Is generated and provided to the second counter 210 and the vertical blank selection block 216, which will be described later, and the vertical blank selection is generated by generating a field separation signal (E / O) as shown in FIG. 4D on the line L27. Provided to block 216, a horizontal synchronizing signal H and a vertical synchronizing signal V2 are generated on lines L28 and L29, respectively, and provided to the first counter 208 and the second counter 210 simultaneously. In addition, the horizontal synchronizing signal H on the line L28 is connected to the other end of the AND gate 212 described later.

On the other hand, the first counter 208, when the PC image of the 640 × 400 mode is input, as shown in Figure 5 as an example, according to the present invention, the blank area (monitor is 640 on a portion of the upper and lower portions of the monitor according to the present invention) At 480, creating a blank section for generating the monitor blank section 40 lines and the bottom 40 lines), the vertical and horizontal lines provided from the buffer block 206 described above via lines L28 and L29. Based on the synchronization signal, a horizontal pulse present in one vertical section is counted, and a blank pulse signal of a predetermined section, i.e., 40H line (odd field blank pulse) between 445H and 35H, as shown in FIG. A blank pulse is generated from a 40H line (even field blank pulse) between 445H and 35H of the next vertical section, and the blank pulse signal generated here is described later through line L31. The blank is provided with straight-selection block 216. In this case, if the preceding 22H shifted vertical section (one frame of the PC image) is defined as one field, that is, an odd field, the next 22H shifted vertical section will be an even field.

On the other hand, the second counter 210 displays an image in the vertical and horizontal synchronizing signals provided from the buffer block 206 described above via lines L28 and L29, based on the selection pulse SP provided from line L26. Detects the vertical section of the odd field and even field for ie, counts the valid horizontal synchronization (active section line in which the actual image data exists) in the vertical section, as shown in FIG. 4F as an example, at 45H. Each odd field vertical section and even field vertical section pulse in a 400H section between 444H are detected, and the detected vertical section pulse signal is connected to one side of the AND gate 212 through a line L30. That is, the second counter 210 detects an active section of 400H line section between 45H and 444H for each vertical section having 42H shifted by 43H.

Next, the AND gate 212 generates an active period horizontal synchronization signal of 400H included in the effective vertical sections 45H to 444H through an AND operation between the horizontal sync pulse on the line L28 and the effective vertical section pulse on the line L30. The generated horizontal synchronizing signal is provided to the frequency multiplier 214 of the next stage.

Meanwhile, the frequency multiplier 214 may be configured as, for example, a 1/2 frequency divider. The frequency multiplier 214 divides the horizontal synchronization signal provided from the AND gate 210 by 1/2 frequency, and is illustrated in FIG. 4G. Generate an output waveform as shown, i.e., 45H, 47H, 49H,---443H horizontal sync pulses taking only odd lines between 45H-444H lines. Here, the generated horizontal synchronizing pulses of 45H, 47H, 49H and 443H are horizontal pulses for the odd field.

At this time, the horizontal synchronization pulses divided by 1/2 from the frequency multiplier 214 are provided to the next buffer BF and the inverter INT, respectively. The buffer BF buffers the horizontal synchronization pulses for inverting timing. Wherein the buffered horizontal sync pulse is provided to the vertical blank select block 216 via line L32.

Inverter INT also inverts the half-divided horizontal sync pulse provided by frequency multiplier 214, and through this inversion, an output waveform as shown in Fig. 4H, i.e., 45H-444H. A horizontal sync pulse of 46H, 48H, 50H,--444H taking only even lines between lines is generated and provided to the next vertical blank selection block 216 through line L33. Here, the generated horizontal synchronizing pulses of 46H, 48H, 50H,---444H are horizontal pulses for even field.

On the other hand, in the vertical blanking selection block 216, when the input image is a non-interlaced 640x480 mode image (that is, when the selection pulse SP on the line L27 is high level), the selection pulse SP on the line L26 is selected. Or in response to the field separator signal (E / O) on line L27, alternately selects the vertical blank signal for the odd field on line L32 and the vertical blank signal for the odd field on line L33 to alternate the blank of FIG. Combination block 300 is provided. That is, when the input image is a non-interlaced 640 × 480 mode image, if the field discrimination signal (E / O) on the line L27 is at a high level, the vertical blank signal for the odd field on the line L32 is selected and output, and on the line L27 If the field division signal E / O is at the low level, the even field vertical blank signal on the line L33 is selected and output.

On the other hand, when the input image is a non-interlaced 640x400 mode image, in the vertical blanking selection block 216, on the basis of the selection pulse SP on the line L26 or the field division signal (E / O) on the line L27, By selecting the combination between line L31 and line L32 as the output or by selecting the combination between line L31 and line L33 as the output, on line L17, a vertical blank signal Vpsp, as shown in FIG. 4I, is generated. That is, a blank pulse on the line L31 (445H-35H line section in the vertical section) as shown in FIG. 4E, when displaying a 640x400 mode image on a monitor having a 640x480 size according to the present invention, FIG. It is a signal for setting a blank area at the bottom of the monitor (bottom 80 lines) as shown in Fig. 5, and this blank pulse is substantially zero on the monitor by generating zero data through sampling. Is displayed.

That is, according to the present invention, in the vertical blank selection block 216, when the selection pulse SP on the line L26 is low level and the field separation signal E / O on the line L27 is high level, the lines L31 and L32 When the combination is selected as its output and output in the odd field vertical blank section of one frame, the selection pulse SP on the line L26 is low level, and the field division signal (E / O) on the line L27 is low level. The combination of L31 and line L33 is selected as its output and output as an even field vertical blank section of one frame.

Therefore, when the input image is a PC image of 640 × 400 mode through this process, the vertical blank section for the odd field having the blank pulse of 40 lines (445H-35H) and the blank pulse of 40 lines (445H-35H) are obtained. The vertical blank section for the even field is alternately selected to output a vertical blank signal Vpsp.

As a result, when a PC image of 640x400 mode is displayed on a 640x480 size monitor, 40 lines (445H-35H) of blank pulses generated in the odd field and 40 lines generated in the even field according to the present invention are displayed. Since blank pulses of (and 445H-35H) are sampled to generate zero data, as shown in FIG. 5 as an example, a blank area of 80 lines (or odd field 40 lines + even field 40 lines) is provided at the bottom of the monitor. The input image is displayed in the form of making.

As described above, according to the present invention, in a PDP television, an image mode having at least fewer lines than the display panel is displayed on the panel, for example, a 640 × 400 mode PC image is displayed on a 640 × 480 size monitor. In this case, by adaptively generating a vertical blank signal suitable for setting the vertical position of the video screen, an image having a line number different from the monitor size can be effectively displayed.

Claims (4)

An apparatus for generating a vertical blank signal for setting a vertical position necessary for displaying an image having a number of lines smaller than the size of a monitor on a monitor of a PDP television receiving a broadcast signal and a PC video signal. On the basis of the horizontal and vertical synchronization signals detected in the input image, a mode for each size of the input image is discriminated and a selection pulse is generated. When the input image is the PC image, a field separation signal is generated. A mode discrimination and pulse shaping block for equally matching the polarity of the vertical frequency; A shift register generating a new vertical synchronizing signal by shifting the detected vertical synchronizing signal by a predetermined 42H line based on the detected horizontal synchronizing signal; A buffer block for buffering the generated selection pulse, field separation signal, detected horizontal synchronization signal and new vertical synchronization signal for timing synchronization between each signal; A blank of 40H lines between 445H and 35H lines for each field in the generated new vertical sync intervals 43H to 449H based on the detected horizontal sync signal and the new vertical sync signal provided in the buffer block. First counters for generating pulses respectively; In response to the generated selection pulse provided from the buffer block, the detected horizontal synchronization signal and the new vertical synchronization signal are inputted to count the active periods in the new vertical synchronization period, and each vertical of 43H-449H lines. A second counter for detecting an active section between 45H-444H lines of the section, respectively; Logic means for generating a horizontal synchronizing pulse in the detected active period through an AND operation between the detected horizontal synchronizing signal and the detected active period provided from the second counter; Frequency-dividing the horizontal synchronizing pulses in the active section provided by the logic means to generate horizontal synchronizing pulses divided by N times, thereby generating a vertical section having an odd field of 200H odd lines in the active section. Frequency multiplier; An inverter for inverting the N-times divided horizontal sync pulses to generate a vertical section having horizontal sync pulses for an odd field of even lines of 200H in the active section; And In response to the generated selection pulse and the generated field discrimination signal, an odd field vertical blank made by combining a blank pulse provided from the first counter with a vertical section having horizontal odd pulses for an odd field of odd lines. Vertical blank selection block alternately generating a vertical blank signal for an even field made by combining a signal and a vertical section having a horizontal pulse for an odd field of the even field and the blank pulse provided from the first counter. Adaptive vertical blank generator in PDTV television. The adaptive vertical blank generator according to claim 1, wherein the input image is a PC image in VGA mode. The adaptive vertical blank generator according to claim 1 or 2, wherein the selection pulse is a logic signal having a high or low level. The PDIP of claim 1 or 2, wherein the mode discrimination and pulse shaping block determines the mode for each size of the input image by counting the number of horizontal synchronization signals in the detected vertical synchronization signal section. Adaptive vertical blank generator in television.