KR20010046766A - Apaaratus for display multi-screen - Google Patents

Abstract

PURPOSE: A multi-screen display device of a digital TV is provided to supply various broadcasting programs by displaying several broadcasting programs in one screen with a simple decoder. CONSTITUTION: A demultiplexor(10) analyzes broadcasting program information included in an additional information signal row of a digital broadcasting for extracting a main program and a plurality of sub programs. A main decoder part(50) decodes a main image signal and a voice signal corresponding to the main program. A sub decoder part(60) decodes sub image signals corresponding to the sub programs. A switch part(110) selects that the sub image signals should be output together with the main image signal according to a predetermined control signal. A signal coupling part(120) compounds and outputs the main image signal and the sub image signals according to the selection of the switch part(110).

Description

Digital TV multi-screen display device {Apaaratus for display multi-screen}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to digital TVs, and more particularly, to a multi-screen display device for displaying a plurality of programs on one screen.

Digital TVs provide viewers with high-definition graphics and high-quality sound that traditional analog TVs did not provide. In addition, digital TV has the advantage of receiving and broadcasting various programs of more channels than analog TV. In addition, analog TV can not be received, but digital TV can receive more information because it broadcasts information about each broadcast program or additional services at the same time in addition to the broadcast program. have.

Regardless of digital TV or analog TV, all TV programs can be provided to viewers only by channels tuned by tuners. That is, a digital TV with one tuner installed may receive only a broadcast program corresponding to one channel to a viewer. Since the analog TV can be attached to multiple tuners, it is possible to provide broadcast programs of multiple channels just by installing a plurality of tuners.

The analog TV demodulates the channel signal tuned by the tuner and separates the video signal and the audio signal from the channel signal. However, the digital broadcast program is divided into video data, audio data and additional data by dividing the digital signal transmitted from the broadcasting station by the demux. Thereafter, the image data and the audio data are decoded by an MPEG decoder and provided to the viewer through the TV screen and the speaker.

Current digital TVs can be equipped with up to five demuxes, and each demux can demultiplex approximately four to six programs. Thus, current digital TVs have the ability to provide viewers with approximately 20 to 30 broadcast programs provided by the same channel, even if they include one tuner.

In reality, however, since the viewer selects and watches only one of a plurality of broadcast programs, the broadcast program data other than the broadcast program video selected by the viewer is ignored. If the viewer wants to see information of another channel, he or she must change the channel tuned in the current tuner by operating the remote controller. When the channel is changed, broadcast program data corresponding to the changed channel is provided to the viewer.

That is, a viewer watching a digital TV broadcast program must change a broadcast channel received by the tuner by operating a remote controller to watch a broadcast program of another channel. That is, a viewer watching a digital TV broadcast program must search all broadcast channels in order to search for a broadcast program to be watched. This puts a heavy burden on the viewer to operate the remote control.

Of course, since the digital TV also receives additional information of the broadcast program, it provides the viewer with an outline of the program serviced on another channel, but the viewer does not operate the remote control that the viewer performs to actually watch the content of the program. It cannot be omitted.

In general, a viewer needs a viewing screen provided in the main display area and a search screen provided in a sub display area smaller than the main screen, rather than simultaneously watching two different programs. There are many. At this time, if the search screen provided by the sub-screen is provided as a video that the viewer can grasp the contents of the broadcast program provided on the sub-screen, there may be a slight disconnection phenomenon. At this time, if a plurality of tuners are installed in the digital TV, the broadcast program screens provided by the tuners may be displayed on a plurality of sub-screens.

However, a digital TV cannot be equipped with a plurality of tuners. The reason for this is as follows. Digital TVs require a demux (DEMUX) that demultiplexes the channel data tuned in the tuner. Therefore, digital TVs must have the same number of demuxes as the number of tuners. This is because the digital TV separates the data of the channel tuned by the tuner into video, audio, and additional information using a demux. therefore. When a plurality of tuners are installed in the digital TV, the size of the main board increases, leading to a problem that the manufacturing cost increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to enable a viewer who watches a digital TV to watch multiple broadcast programs on one screen without adding a tuner to the digital TV.

1 is a block diagram schematically showing a multi-screen display of a digital TV of the present invention.

2 is a waveform diagram illustrating a plurality of subprograms arranged in a temporal order by a time divider;

FIG. 3 is a diagram illustrating a screen in which a size of a sub image is reduced by a predetermined ratio by a down scaler unit; FIG.

4 is a diagram illustrating that a position of a sub image is changed by a position designation unit.

Symbol description for main parts of drawing

10: demultiplexer 20: SI extraction unit

30: sub decoder switch 40: time division unit

50: main decoder section 60: sub decoder section

70: down scaler 80: location

90: mixer section 100: memory

110: switch unit 120: signal coupling unit

130: multiple image control unit 140: key input unit

The digital TV of the present invention is characterized by providing a plurality of broadcast programs to viewers by simply adding an MPEG decoder without using a plurality of tuners.

The multi-screen display device of the present invention includes a demultiplexer which analyzes an additional information signal string and extracts a main program and a subprogram, a main decoder that decodes a main video signal and an audio signal corresponding to the main program, and a subprogram. A sub decoder which decodes the sub video signal, a switch which selects whether or not to output the sub video signal to the main video signal in accordance with the control signal, and a combination of the main video signal and the sub video signal according to the selection of the switch part. It is configured to include a signal coupling unit for outputting. 1 is a block diagram schematically illustrating a multi-screen display device of the present invention.

The demultiplexer 10 extracts an additional information signal sequence from a transport stream (TS) of digital broadcasting, and finds broadcast program information from the additional information signal sequence. The demultiplexer 10 extracts the main program and sub programs by analyzing broadcast program information. At this time, the main program is generally one, but there may be a plurality of subprograms. The reason is that the demultiplexer 10 installed in the general digital TV, that is, the DEMUX, may analyze 4 to 6 broadcast programs.

The main decoder unit decodes the main video signal and the audio signal from the video signal sequence with reference to the main program information extracted by the demultiplexer 10. This main decoder unit is composed of an MPEG decoder.

The sub decoder decodes the sub video signal from the video signal sequence by referring to the sub program information extracted by the demultiplexer 10. The sub decoder unit sequentially decodes the sub video signal from the video signal sequence in a sequence arranged by the time division unit 40 and the time division unit 40 sequentially arranging sub programs extracted by the demultiplexer 10. A sub-decoder 60, a down scaler 70 for reducing the size of the sub-picture represented by the sub-picture signal by a predetermined ratio, and a positioning unit 80 for designating the position of the sub-picture reduced in the down-scaler It is configured to include.

The time division unit 40 installed in the sub decoder unit arranges a plurality of sub programs in a temporal order as shown in FIG. This is because the decoder cannot decode several video signals at one time, and thus decodes the sub video signals with a predetermined time difference.

The subdecoder decodes the sub video signals corresponding to the sub program in the order arranged by the time division unit 40. The sub decoder 60 is configured as an MPEG decoder similarly to the main decoder unit.

The down scaler 70 reduces the size of the sub image represented by the sub image signal by a predetermined ratio as shown in FIG. 3. The ratio is set to such an extent that the user does not interfere with the viewing of the main image represented by the main image signal. In addition, when there are several sub-images to be expressed, the ratio may be appropriately adjusted.

The positioning unit 80 designates the position of the sub-image reduced in the down scaler. In general, although the sub image is preferably located at the corner of the TV screen, the position may be changed according to the taste of the viewer or the aspect ratio of the main image as illustrated in FIG. 4. At this time, if the viewer presses the position change key with a remote controller or the like to change the position of the sub image, the position change signal according to the position change key is input to the position determining unit 80 to change the position of the sub image. .

The sub decoder unit further includes a mixer unit 90 that collects a plurality of sub images into one screen and an additional memory 100 that stores the sub images.

When there are a plurality of sub images decoded by the sub image signal, the mixer 90 processes the sub image signals to collect the plurality of sub images into one screen. The memory 100 stores the sub-images collected by the mixer 90 and provides them when the user needs them.

The switch unit 110 selects whether or not to output the sub video signal to the main video signal according to a predetermined control signal. That is, the switch 110 determines whether to display the sub-image stored in the memory 100 on the screen according to a user's manipulation.

The signal combiner 120 outputs a combination of the main video signal and the sub video signal according to the selection of the switch 110. As a result, the sub-image stored in the memory 100 is combined with the main image by the signal combination unit 120 according to a user's operation and implemented on the screen.

In addition, the multi-screen display apparatus of the present invention is a multi-screen display for controlling the operation of the sub-decoder unit and the operation of the switch unit 110 by the control signal input unit and the key input signal for generating a predetermined key input signal according to the user's operation The image controller 130 is further configured to further include.

The control signal input unit includes a remote controller or a keypad of the TV and includes an operation key for allowing a user to select whether to output a sub image.

The multi-image controller 130 interprets the key input signal generated by the control signal input unit to generate a control signal that determines the operation of the sub decoder unit and the selection of the switch unit 110.

The multi-screen display device of the present invention operates on the following principle.

The transport stream transmitted by the broadcasting station includes a video signal sequence, an audio signal sequence, and an additional information signal sequence. The signal sequence included in the transport stream is separated by the demultiplexer 10, and the demultiplexer 10 of the present invention extracts SI (Sytem Information) of the additional information signal string to search for a PMT (Program Management Table). After that, the broadcast information recorded in the PMT is searched. Since the broadcast information includes information on a main program and a sub program currently being serviced, the main program information and sub program information are extracted by the demultiplexer 10. At this time, the SI information is extracted by the SI extraction unit 20.

When the main program information and the sub program information are extracted, the video signal sequence corresponding to the main program is decoded into the main image by the main decoder unit, and the video signal sequence corresponding to the sub program is decoded into the sub image by the sub decoder unit. At this time, the main image is implemented on the screen in real time.

The voice signal sequence corresponding to the sub program may or may not be decoded as necessary, but is not output through the speaker. This is because the voice signal corresponding to the main program and the voice signal corresponding to the sub program should not be mixed.

Multiple subprograms cannot be decoded simultaneously by one decoder. Therefore, if there are a plurality of subprograms, the plurality of subprogram video signal sequences are sequentially decoded with a predetermined time difference. Therefore, each sub image is not implemented on the screen in real time, but is implemented on the screen with a slight unnatural break. However, since the sub image only needs to perform a screen search or a reference role to the viewer, even if there is a certain amount of disconnection, the sub image is not enough to disturb the viewer.

In addition, the sub picture is reduced in size by the down scaler so as not to disturb the viewing of the main picture. In particular, when multiple sub-pictures are to be implemented at once, the downscaler reduces the size of the sub-pictures so that viewing of the main video is not disturbed even if all the sub-pictures are implemented on one screen.

The position of the sub-image reduced in size by the down scaler is implemented on the screen by the positioning unit 80. In general, the sub image is preferably located at the corner of the screen so that the viewer does not interfere with the main image. In particular, when the aspect ratio is 16: 9, an empty area is generated in addition to the area where the main image is implemented. At this time, it is more preferable that the positioning unit 80 implements the sub image in the blank area. Of course, the position of the sub image may be changed to a position desired by the viewer.

When the position of the sub image is determined, one sub image is implemented for each region where the sub image is implemented. If there are several sub-images, the area is required as many as the number of sub-images. At this time, in order to represent several sub-images in one region, each sub-image must be collected on one screen. This is done by the mixer. That is, a plurality of sub-pictures are combined by a mixer and collected into one screen. The finally expressed sub image is stored in the memory 100 installed separately.

The present invention may be configured such that the sub image is always implemented on the screen, but more preferably, the sub image is implemented on the screen according to a viewer's selection.

If the viewer manipulates the key input unit 140 to implement the sub image on the screen, a control signal is generated from the multi-image control unit 130 by the key input unit 140. The control signal controls the switch unit 110 and the sub decoder switch 30 so that the sub image is displayed on the screen. Then, the video signal sequence corresponding to the sub program is decoded into the sub image through the sub decoder unit, and the decoded sub image is selected through the switch unit 110 and combined with the main image through the combiner to be implemented on the screen.

When the user wants to change the position of the sub image through the key input unit 140 while the sub image is implemented, a signal for changing the position is input to the position designation unit 80 so as to pre-register a region of the sub image to be implemented. Change the set position.

In addition, if the viewer does not want the sub image, the sub decoder unit and the switch unit 110 do not output the sub image, and only the main image is implemented on the screen.

According to the present invention, unlike a conventional digital TV, multiple broadcast programs received through one channel can be displayed on one screen only by a simple decoder instead of a separate tuner, thereby providing a more diverse broadcast program screen to a viewer. It works. In addition, the present invention has an effect of enabling the viewer to search the broadcast program image more easily while reducing the effort of manipulating the remote control by implementing the characteristics of the multi-channel and the function of the multiple image of the digital TV.

Claims (4)

A demultiplexer which extracts a main program and a plurality of sub programs by analyzing broadcast program information included in an additional information signal sequence of digital broadcasting; A main decoder unit for decoding the main video signal and the audio signal corresponding to the main program extracted from the demultiplexer; A sub decoder configured to decode a sub video signal corresponding to the sub programs extracted by the demultiplexer; A switch unit for selecting whether to output the sub video signal to the main video signal together according to a predetermined control signal And a signal combiner configured to compositely output the main video signal and the sub video signal according to the selection of the switch unit. The method of claim 1, wherein the sub decoder unit A time division unit sequentially arranging the subprograms extracted by the demultiplexer; A sub decoder sequentially decoding the sub video signals corresponding to the sub programs in the order arranged by the time division unit; A down scaler unit which reduces a size of a sub image represented by the sub image signal by a predetermined ratio; And a position designator for changing and designating a position of the sub-image reduced in the down scaler according to an external control signal. The method of claim 2, A mixer unit for collecting the plurality of sub-pictures into one screen when the sub-pictures are decoded by the sub-video signal; And a memory for storing the sub-images collected by the mixer unit. The method of claim 1, A control signal input unit for generating a predetermined key input signal by a user's operation, And a multi-image control unit for controlling whether the sub decoder unit operates by the key input signal, applying the control signal to the switch unit, and changing the position of the sub image. Multiscreen Display.