KR200214420Y1 - Screen aspect ratio converters for wide display devices - Google Patents

Abstract

The present invention relates to a screen aspect ratio conversion device for a wide display device, and more particularly, a computer signal in VGA mode and an NTSC TV signal are simultaneously input, and NTSC TV signals in the form of R, G, and B Signal conversion, and the converted TV signal and the computer signal can be selectively displayed and sampled according to the clock speed of the frequency generating circuit, and 16 × of a screen having an aspect ratio of 4x3 The present invention relates to a screen aspect ratio converting apparatus for a wide display device capable of preventing distortion of an image in displaying on a wide screen.

Description

Screen aspect ratio converters for wide display devices

FIG. 1 (a) is a diagram showing a screen in which the aspect ratio is 4x3.

FIG. 1 (b) is a diagram showing a screen in which the aspect ratio is 16x9.

FIG. 1 (c) is a diagram showing a screen on which a 4x3 phase screen is displayed on a screen with a aspect ratio of 16x9.

2 is a block diagram showing a screen aspect ratio conversion device of a conventional widescreen TV.

3 is a circuit diagram illustrating a screen aspect ratio conversion device for a wide display device according to an embodiment of the present invention.

The present invention relates to a screen aspect ratio conversion device for a wide display device, and more particularly, to receive a computer signal in the VGA mode and an NTSC TV signal at the same time and selectively display it, and according to the clock speed of the frequency generator circuit. A screen aspect ratio conversion device for a wide display device capable of sampling and displaying a screen having a 4 × 3 aspect ratio on a 16 × 9 wide screen.

In recent years, due to the rapid development of semiconductor devices, the technology of hardware and software related to computers has been growing remarkably, and the development of multimedia in the category has achieved remarkable results. to be.

As the multimedia culture develops, users need display devices having clearer picture quality, lively sound quality, and large sized screens.

In addition, with respect to human visual characteristics, the preference of display devices having a ratio of width x length to 16 x 9 is increasing.

However, despite the above trend, conventional monitors simply display a signal of 4 × 3 ratio of width × length having various frequencies output from a computer on a screen of 4 × 3 of width × length, and also display a wide screen. TVs implement a wide deflection of 15.75 KHz single frequency.

FIG. 1 (a) is a diagram showing a screen in which the aspect ratio is 4x3.

FIG. 1 (b) is a diagram in which a 4x3 image is distorted and displayed on a screen having a aspect ratio of 16x9.

FIG. 1 (c) is a diagram showing a screen on which a 4x3 phase screen is displayed on a screen having a aspect ratio of 16x9 in accordance with an embodiment of the present invention.

As shown in the figure, when displaying a general TV screen (Fig. 1 (a)) having a ratio of width × length of 4 × 3 on a wide TV having a ratio of width × length of 16 × 9, the first (b) diagram is shown. The horizontally distorted screen is displayed as well. The reason for this is as follows.

When the horizontal lengths are L1 and L2 and the vertical lengths are H1 and H2, if the vertical lengths are the same, that is, when H1 = H2, the ratio of the horizontal lengths (L1: L2) is 3: 4.

Therefore, in order to display as shown in FIG. 1 (c) without distortion of the image, the horizontal length L2 of FIG. 1 (b) should be corrected by 3/4 times.

The conventional patent for aspect ratio conversion (hereinafter referred to as ARC) is a patent applied to a TV signal (U.S. Patent No. 5,159,438), which is applied to a wide TV having a 16 × 9 aspect ratio. Technology. In the conventional NTSC TV signal, the ratio of width × length has a ratio of 4 × 3.

The ARC patent applies to wide TVs having a ratio of 4x3 to a ratio of 4x3 to 4x9.

2 is a block diagram showing a screen aspect ratio conversion device of a conventional widescreen TV.

And a digital video decoder 11 for receiving the airwaves transmitted from the broadcasting station and detecting the video signal, and a hue decoder 12 for detecting the hue signal of the video signal detected by the digital video decoder 11.

In addition, an image conversion device (ARC) 13 for receiving an aspect ratio conversion of an image signal and a color signal transmitted from the digital video decoder 11 and the color tone decoder 12, and the image conversion device (ARC) 13. It is connected to the rear end of the multifunction apparatus 14 and a driver 15 for displaying image information on the CRT 16.

However, such a conventional ARC patent discloses the use of a filter for interpolation after analog / digital conversion of a luminance signal and a hue signal in a TV signal, and a read and write clock speed of a memory. There was a problem of using a complicated filter using the compressor method by the difference.

In addition, NTSC-based TV signals have a horizontal frequency of 15.75 KHz and display 30 frames per second.

Therefore, the conventional technology can only process NTSC signals, so it was not applicable to a computer using a wide display device.

In order to solve this problem, the present invention selects an NTSC-based TV signal and a computer signal in VGA mode, selects a desired signal, and uses a frequency generating circuit to sample a synchronization signal of the selected signal to a wide display device having a 16: 9 aspect ratio. An object of the present invention is to provide a screen aspect ratio converting device for a wide display device that enables display.

The present invention for achieving the above object, the screen type for a wide display device for displaying a screen with a horizontal × vertical ratio of 4 × 3 on a 16 × 9 wide screen by receiving a computer signal and a TV signal simultaneously In an aspect ratio converter;

A signal converter for converting the NTSC TV signal into R, G and B signals and horizontal and vertical registered signals;

A multiplexer for receiving a TV signal through the signal converter and a computer signal in VGA mode simultaneously and selectively outputting a desired signal;

A sampler for digitizing a signal selected and output by the multifunction apparatus;

A frequency generating circuit for generating a clock for controlling a sampling rate of the sampler;

And a line memory configured to repeatedly read / write the R, G, and B signals transmitted from the sampler to provide data necessary for driving the CRT.

Also, among the signals input to the multifunction apparatus, a TV signal mixed with a synchronous signal and a frequency modulated signal is converted into an R, G, B type signal, and the frequency generation circuit is used to sample pixel data in VGA mode. It is characterized by generating a frequency of 25 MHz and displaying it at a rate of 33 MHz to display a 4x3 video signal on a 16x9 screen.

Hereinafter, the configuration and operation of the present invention will be described with reference to the accompanying drawings.

3 is a circuit diagram illustrating a screen aspect ratio conversion device for a wide display device according to an embodiment of the present invention.

As shown, the present invention has an antenna 21 for receiving airwaves transmitted from a broadcasting station, and a tuner unit 22 for separating and processing the airwaves received by the antenna 21.

A filter 23 for detecting a video signal from the tuner unit 22 and a signal converter 24 for converting the detected video signal into R, G, and B signals and a synchronization signal in VGA mode are provided.

A multi-function device 25 for receiving and selectively outputting a TV signal converted into R, G, and B forms by the signal converter 24 and a computer signal in VGA mode;

And a sampler 26 for digitizing the signal selected and output by the multifunction peripheral 25.

In addition, the frequency generating circuit 27 for generating a clock for controlling the sampling rate of the sampler 26,

The R, G, and B signals transmitted from the sampler 26 are repeatedly read / write, and a line memory 28 and a driver 29 are provided to provide data for driving the CRT 29.

The operation of the present invention configured as described above will be described.

First, the TV signal received through the antenna 21 is required to be unified in the form of data in order to simultaneously use the NTSC video signal detected by the tuner 22 and the filter 23 and the display signal of the VGA computer. .

The reason is that the TV signal source inputted as NTSC signal is a VGA signal output from a computer where a chrominance signal (hereinafter referred to as a C signal) and a luminance signal (hereinafter referred to as a Y signal) are applied as a composite signal. This is because the signal of the R, G, B color signal and the horizontal sync and vertical sync signals are separately outputted.

In order to use the luminance signal and the chrominance signal of the conventional method, it is necessary to convert the display signal of the computer inputted in the form of R, G, and B into Y and C forms. And this Y, C signal will be inconvenient to be converted to R, G, B signal form and output again.

Therefore, initially, the R, G, B type signals should be used as basic ARC input signals, and the signal converter 24 converts the signals into R, G, B types.

The multiplexer 25 receiving the TV signal modified in the form of R, G, and B and the computer signal in the VGA mode at the same time selects and outputs a desired signal.

In order to digitize the selected signal, sampling at the sampler 26 is required, and the sampling rate at this time uses a frequency of 25 MHz in the frequency generating circuit 27 to sufficiently express the resolution.

At this time, when sampling at a rate of 25 MHz, approximately 800 pixel data can be sampled for a 31.5 kHz horizontal frequency signal.

However, this is a sampling clock for a monitor of generalized resolution, and the clock speed of the frequency generating circuit can be varied. The reason for this is that in the case of a monitor, a single frequency is not input as in a TV, so signals of various resolutions are input to various input frequencies. Therefore, when used as a monitor, the sampling frequency should be adjusted by recognizing the resolution of the input signal when sampling the video data. This is a means for preventing image distortion from occurring when restoring video data when the sampling number (Dot number) is fixed.

This sampled pixel data is written onto the line memory 28 at a rate of 25 MHz. Pixel material stored on the line memory 28 is read at a rate of 33 MHz and displayed on the wide monitor 30.

When implemented as described above, NTSC TV and computer signals can be displayed without distortion on a wide screen having a 16: 9 aspect ratio.

As described above, the present invention changes the sampling clock speed when sampling is performed at the clock speed provided by the frequency generating circuit in the wide display device that uses the NTSC TV signal and the VGA signal computer signal. It is effective to prevent distortion of the image that appears when the 4 × 3 screen is displayed on the 16 × 9 screen.

Claims (4)

A screen aspect ratio conversion device for a wide display device for receiving a computer signal and a TV signal simultaneously and displaying a screen having a 4 × 3 aspect ratio on a 16 × 9 wide screen; A signal converter that converts NTSC-type TV signals into R, G, B signals, and horizontal and vertical synchronization signals, and a multifunction device that selectively receives desired TV signals and computer signals in VGA mode through the signal converters and selectively outputs desired signals. (Multiplexer), a sampler for digitizing the signal selected and output by the multifunction apparatus, a frequency generating circuit for generating a clock for controlling the sampling rate of the sampler, and R, G, B signals transmitted from the sampler And a line memory for repeating read / write to provide data necessary for CRT driving. The screen type of claim 1, wherein the TV signal, in which a synchronous signal and a frequency modulated signal are mixed, is converted into an R, G, B type signal and received. Aspect ratio converter. The apparatus of claim 1, wherein the frequency generating circuit varies the clock speed according to the resolution of the wide display device so that the sampling rate can be properly adjusted to the resolution. The frequency generating circuit of claim 1, wherein the frequency generating circuit generates a frequency of 25 MHz to sample pixel data in VGA mode, and displays the 4x3 image signal at a speed of 33 MHz to display a 16x9 screen. A screen aspect ratio conversion device for a wide display device.