KR19990042402A - How to correct screen size on TV - Google Patents

Abstract

According to the present invention, a television having a PIP function corrects the number of horizontal lines of a sub picture to be equal to the number of horizontal lines of a main picture so that the screen size of the main picture and the sub picture can be matched to a user without inconvenience. A method of correcting a screen size in a television that is provided so that when the main screen is NTSC and the sub screen is PAL, the number of horizontal lines of the subscreen is the number of horizontal lines of the main screen, and the sixth horizontal line from the first horizontal line of the subscreen. Display the line by combining the up and down horizontal lines at a predetermined ratio and reducing and reducing them to five horizontal lines.If the main screen is PAL and the sub screen is NTSC, the number of horizontal lines of the sub screen is subtracted. From the first horizontal line to the fifth horizontal line of the screen, the horizontal line is composed of six horizontal lines By repeatedly displaying the interpolated steps, the visual asymmetry of the main / sub picture can be eliminated to provide visual convenience to the viewer.

Description

How to correct screen size on TV

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screen size correcting method in a television, and in particular, a television having a PIP function corrects the horizontal lines of a sub screen in the same way as the horizontal lines of a main screen, so that a main screen and a sub-screen are corrected. The present invention relates to a method for correcting a screen size on a television, in which the screen sizes of the TVs are matched so that a user can watch without inconvenience.

In general, a picture in picture (PIP) function of a television includes first and second tuners for receiving and tuning a broadcast signal transmitted from a broadcasting station, so that a screen can be divided into a main region and a sub region to simultaneously watch two broadcast signals. For example, the viewer may simultaneously search for or watch another broadcast signal of the sub picture displayed in the sub area while watching the broadcast of the main screen displayed in the main area.

In this case, the PIP process converts two broadcast signals or one broadcast signal (for a sub-screen) into a digital signal, performs image reduction processing for adjusting the screen size, and synthesizes the two broadcast signals to match the desired home screen position. Convert it back to a signal and process it.

Therefore, the PIP function allows a viewer to watch two broadcasts at the same time, thereby enabling a search function of searching for another broadcast on a sub-screen while watching a desired broadcast on a main screen.

1 is a schematic block diagram of a television having a conventional general PIP function, and includes a key input unit 10, a microcomputer 20, first and second tuner units 30 and 50, and first and second image signal processing units (FIG. 1). 40 and 60, a PIP processing unit 70, an RGB converter 80 and a monitor 90.

In such a configuration, the key input unit 10 is provided with a plurality of keys for performing the operation of the television outputs a key signal corresponding to the user's key operation, typically using a remote control that can be input from a remote location A key signal corresponding to a key operation is loaded on a predetermined infrared signal and transmitted, the received infrared signal is received, detected, amplified, and waveform-formed to output the received key signal.

The microcomputer 20 may control the first and second tuner units 30 and 50, the first and second image signal processors 40 and 60, and the PIP processor 70 based on the key signal from the key input unit 10. Selective control to control the overall operation of the television.

Meanwhile, the first and second tuners 30 and 50 output the broadcast signals received and tuned to the channels corresponding to the control of the microcomputer 20 to the first and second image signal processing units 40 and 60, respectively.

Next, the first and second video signal processors 40 and 60 separate the video signals from the broadcast signals from the first and second tuners 30 and 50 and output them to the PIP processor 70.

Then, the PIP processing unit 70 is a means for processing each video signal from the first and second video signal processing units 40 and 60 into a main / sub picture and forming a single screen under the control of the microcomputer 20. After converting the two video signals applied based on the preset size of the housewife screen to a digital signal, synthesizes the two broadcast signals to match the size of the housewife screen and converts them into analog signals and outputs them to the RGB converter 80. .

On the other hand, the R.G.B converter 80 converts the R.G.B signal, amplifies, and outputs the video signal from the PIP processing unit 70 on the monitor 90.

Next, with reference to the detailed block diagram of FIG. 2 which attached the above-mentioned PIP processing part 70, it demonstrates further.

As shown in the figure, the PIP processing unit 70 includes the first and second A / D converters 200 and 220, the first and second storage units 210 and 230, the signal processor 240, and the D / A converter 250. ).

In this configuration, the first and second A / D converters 200 and 220 convert the respective analog video signals from the first and second video signal processors 40 and 60 into digital video signals and convert the signals into one horizontal line unit. Output to the first and second storage units 210 and 230, respectively.

Then, the first and second storage units 21 and 230 temporarily store digital image signals from the first and second A / D converters 200 and 220 and output the temporary digital image signals to the signal processor 240.

On the other hand, under the control of the microcomputer 20, the signal processor 240 may convert the digital image signal for the main screen and the digital image signal for the sub-screen applied from the first and second storage units 210 and 230 to the main screen and the sub-screen. The digital image signal synthesized by one horizontal line unit is applied to the D / A converter 250 in units of horizontal lines corresponding to the size of the screen.

Then, the D / A converter 250 converts the digital video signal obtained by synthesizing the main / sub picture from the signal processor 240 into an analog video signal and outputs the analog video signal to the R.G.B converter 80.

On the other hand, in recent years, televisions can process all broadcast signals having different broadcast standards, so that, for example, NTSC and PAL broadcast signals can be arbitrarily selected and viewed.

However, the NTSC standard has 525 horizontal lines and the PAL method has 625 horizontal lines. Accordingly, when the main screen and the sub-screen are different from each other when the main screen and the sub-screen are simultaneously viewed by the PIP function, as shown in FIG. 3, the asymmetry of the screen size causes the viewer to visually feel awkward. There was this.

An object of the present invention is to broadcast the main screen and the sub-screen broadcast method to prevent the relative screen size from being asymmetric due to the difference in the number of horizontal lines in the broadcast method of the main screen and the sub-screen in a television having a PIP function In this case, the present invention provides a screen size correction method for a television that allows a sub-picture image to be corrected and displayed in the form of a video signal of the main screen.

In the television according to the present invention, the screen size correcting method of the television has a PIP function capable of simultaneous broadcasting. As a method for correcting asymmetry, if the main screen is an NTSC system and the sub screen is a PAL method, the horizontal line number of the sub screen is reduced and corrected for display, and the main screen is a PAL method and the sub screen. The NTSC method includes increasing and correcting the horizontal lines of the sub-screen and displaying the same.

On the other hand, the horizontal line reduction correction, characterized in that by repeatedly displaying the steps of reducing the number of horizontal lines by combining the first horizontal line from the first horizontal line of the sub-screen to be reduced correction up and down horizontal lines in a predetermined ratio to five horizontal lines do.

On the other hand, the horizontal line increase correction is characterized by repeatedly displaying the first horizontal line of the sub-screen to be incrementally corrected by combining the fifth horizontal line with the upper and lower horizontal lines at a predetermined ratio and interpolated into six horizontal lines. do.

1 is a schematic block diagram of a television having a conventional general PIP function;

2 is a detailed block diagram of the PIP processing unit of FIG.

3 is an asymmetric PIP screen for explaining the present invention

4 is a detailed block diagram of a PIP processing unit according to the present invention.

5 is a diagram for explaining horizontal line interpolation and reduction according to the present invention.

<Explanation of symbols for main parts of the drawings>

300, 320: first and second A / D conversion unit 310, 330: first and second storage unit

340: line control unit 350: signal processing unit

360: D / A converter

The above objects and various advantages of the present invention will become more apparent from the preferred embodiments of the 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.

4 is a detailed block diagram of the PIP processing unit 70 employed in accordance with the present invention. The first and second A / D conversion units 300 and 320, the first and second storage units 310 and 330, the line control unit 340, The signal processor 350 and the D / A converter 360 are included.

In this configuration, the first and second converters 300 and 320, the first and second storage units 310 and 330, the signal processor 350, and the D / A converter 360 are the same as those of the conventional PIP processor. And a line controller 340 for correcting a screen size based on the digital image signal from the second storage unit 320 in which the digital image signal is stored.

Next, a screen size correction process according to a preferred embodiment of the present invention in a television including the above-described configuration unit will be described in detail with reference to FIG.

First, when watching two broadcasts simultaneously on the main screen and the sub-screen using the PIP function, the microcomputer 20 lines the line to match the horizontal lines of the main screen and the sub-screen when the broadcasting methods of the two broadcast signals being viewed are different. The control unit 340 recognizes the broadcast method of the main screen and the sub-screen broadcast signal.

At this time, the broadcasting method of the main screen, that is, the broadcasting method of the digital video signal passing through the first storage unit 310 is a PAL method of 625 horizontal lines, and the digital video signal of the sub picture passing through the second storage unit 330 is 525 horizontal. If the line is NTSC, the line controller 340 interpolates the digital image signal applied in units of horizontal lines from the second storage unit 330 to the signal processor 350 by interpolating in units of horizontal lines.

In detail, the output is interpolated into six horizontal lines based on five horizontal lines. The first horizontal line is output to the signal processing unit 350 as it is, and the second horizontal line corresponds to the first horizontal line component (level) and The second horizontal line component is synthesized and output at a ratio of 1: 4.

Next, the third horizontal line synthesizes and outputs the second horizontal line component and the third horizontal line component in a ratio of 2: 3.

On the other hand, the fourth horizontal line is synthesized and output the third horizontal line component and the fourth horizontal line component in a ratio of 3: 2.

The fifth horizontal line synthesizes the fourth horizontal line and the fifth horizontal line component at a ratio of 4: 1, and outputs the result.

Finally, the sixth horizontal line interpolates the horizontal line of the entire screen by repeating the process of outputting the fifth horizontal line as it is and interpolating the next five horizontal lines back to the six horizontal lines.

Meanwhile, the broadcasting method of the main screen, that is, the broadcasting method of the digital video signal passing through the first storage unit 310 is NTSC of 525 horizontal lines, and the digital video signal of the subscreen passing through the second storage unit 330 is 625 horizontal. In the PAL method of the line, the line controller 340 reduces the digital image signal applied in units of horizontal lines from the second storage unit 330 to units of horizontal lines, and applies it to the signal processor 350.

In detail, the six horizontal lines are reduced to five horizontal lines, and the first horizontal line is output as it is, and the second horizontal line is the second horizontal line component (level) and the third horizontal line component. Outputs the result of a composite operation in a 3: 1 ratio.

The third horizontal line then synthesizes and outputs the third horizontal line component and the fourth horizontal line component in a ratio of 2: 2.

On the other hand, the fourth horizontal line is synthesized by outputting the fourth horizontal line component and the fifth horizontal line component in a ratio of 1: 3.

The fifth horizontal line outputs the sixth horizontal line to the signal processor 350 as it is, and reduces the horizontal line, and performs the above-described reduction operation from the seventh horizontal line to be applied again.

Accordingly, the size of the sub-screen applied to the signal processor 350, that is, the horizontal resolution, is matched with the main screen through the above-described interpolation and reduction processing, so that the user can view the main screen and the sub-screen at the same resolution.

On the other hand, it will be understood by those skilled in the art that various changes and modifications can be made without departing from the spirit of the present invention.

As described above, according to the present invention, when a TV having a PIP function and capable of simultaneously watching other broadcasting methods such as NTSC or PAL system has a different number of horizontal lines because the broadcasting method of the main picture and the sub picture currently being viewed is different. For example, the relative screen size is symmetrical by line interpolation or line reduction, thereby providing visual convenience to the viewer.

Claims (3)

As a method for correcting the asymmetry of the main picture and the sub picture due to the inconsistency of the horizontal resolution because the broadcasting method of simultaneous viewing of the main picture and the sub picture is different from the TV equipped with the PIP function capable of simultaneous broadcast viewing, If the main screen is NTSC and the sub-screen is PAL, displaying the horizontal lines of the sub-screen by decreasing the number of horizontal lines of the main screen; If the main screen is PAL and the subscreen is NTSC, increasing and correcting the number of horizontal lines of the subscreen to display the screen size. The method of claim 1, wherein the horizontal line reduction correction is performed by combining the first and second horizontal lines from the first horizontal line of the sub-screen to be reduced-corrected by combining the upper and lower horizontal lines at a predetermined ratio and reducing them to five horizontal lines. Display size correction method for television, characterized by displaying. The method of claim 1, wherein the horizontal line number increment correction comprises repeating the interpolation of six horizontal lines by combining a horizontal line from the first horizontal line to the fifth horizontal line of the sub-screen to be incrementally corrected at a predetermined ratio. Display size correction method for television, characterized by displaying.