KR20000060554A - Apparatus for connecting external image source device to digital television - Google Patents

Abstract

PURPOSE: An interface device for an outer image source and a digital television is provided to convert an output signal from a digital set top box as well as from a computer to the digital television. CONSTITUTION: The interface device for an outer image source and a digital television includes a YUV conversion/synchronous divider(10), a RGB converter(20), a multiplexor(25), an analog/digital converter(30), a format converter(40) and a controller(35). The YUV conversion/synchronous divider(10) divides a horizontal and vertical synchronous signal from an output of a digital set top box including digital luminance signal(Y), color signal(Pb,Pr) and horizontal and vertical synchronous signals, and converts the YPbPr signal to a YUV signal. The RGB converter(20) converts the YUV signal to a RGB signal. The multiplexor(25) receives the converted RGB signal and a RGB signal from a computer and output selectively according to the signal selection signal. The analog/digital converter(30) receives the output of the multiplexor and performs digital/analog conversion. The format converter(40) determines whether the output of the multiplexor is the converted RGB signal or the input RGB signal and convert the format into a predetermined form required by a digital television.

Description

Apparatus for connecting external image source device to digital television}

The present invention relates to a digital television, and more particularly, in a digital television, an external image source by converting and outputting an image signal output from an external image source device such as a digital set-top box or a computer into a display system required for a digital television. The present invention relates to an external video source device connecting device of a digital television that can easily connect a device to a digital television.

The wind of digitization originated from computers is spreading to TV. Digital technology, which has been applied to computers since the 1960s, has since spread to telecommunications and home appliances, causing a new technological revolution. Taking advantage of this technological trend, the commercialization of digital television is imminent with the start of digital broadcasting, and digital television is expected to be a catalyst for leading the popularization of multimedia.

Since the 1980s, computer and communication (C & C), or computer and communication, has been converged. As a result, computers have emerged as multimedia terminals in the 90's. In the future, C & B (communication) is the convergence of communication and broadcasting through digitalization of broadcasting. It is expected that the era of broadcasting and the complete multimedia era will develop. In addition, digital television is expected to dominate the competition for multimedia handsets.

Leading the Popularization of Multimedia Digitalization of broadcasting is a catalyst for full-fledged development of the multimedia era, but it is difficult to popularize multimedia by computers alone because of the limitation of the dissemination of computers. However, when the television is equipped with multimedia functions, the popularization of multimedia can be easily achieved. In order to enjoy the benefits of multimedia such as VOD in every home, at least one information terminal can be distributed in each home, because the most suitable product is TV. In order for a television to perform a multimedia function, digitalization must be performed, and digitalization of broadcasting, which is an infrastructure, must be made in advance.

However, with the launch of digital broadcasting, the era of full-scale digital television is expected to arrive. Of course, there is a possibility that computers will perform the control functions of all the electronic products spread in the home in the future, but in this case, digitalization of broadcasting should be premised.

Digital broadcasting has several advantages over analog broadcasting. First of all, digital broadcasting can provide a clearer and brighter screen like a movie and a clearer sound like a compact disc. In addition, since digital broadcasting uses data compression technology, multiple channels are possible.

The existing analog broadcasting frequency 1 channel (6MHz) will be able to export three to four digital broadcasts. In the case of high-definition digital television broadcasting that requires a large amount of information transmission rather than ordinary digital broadcasting, the advantages of multi-channel may not occur because all existing broadcasting bands must be used. However, from a broadcaster's point of view, it is difficult to produce all programs at the high-definition digital television broadcast level, so it is highly likely that high-definition digital television broadcasts will be exported only at certain times, such as prime time zones.

On the other hand, digital broadcasting is available for a variety of value-added services, for example, viewers can watch a variety of information, such as the details of the actors and athletes while watching a drama or athletics on the TV screen.

Digital satellite broadcasting has already been commercialized in the United States, the United Kingdom, and Japan, and test broadcasts have been made since 1998 in Korea. However, without the digitalization of terrestrial broadcasting, the development of the digital broadcasting era is impossible. In the case of satellite broadcasting, there is a need for expensive receiving equipment, so the demand is limited, whereas terrestrial broadcasting is intended for all households with TV receivers.

The digital TV currently being developed under such technical background is basically a product that is developed in the direction of high definition, high resolution, and enlargement, so the consumer is burdened with a very expensive purchase cost. Efforts are being made to enhance the product competitiveness by improving user satisfaction by supporting various additional functions in addition to the functions unique to digital television.

On the other hand, by developing a separate set-top box that can receive digital broadcasts without using expensive digital televisions, it is possible to receive digital broadcasts using existing NTSC televisions or to connect with a computer to obtain a high resolution format. The way to drive is known one after another.

As mentioned earlier, in the future, not only the performance inherent in digital television, but also the additional functions that can be easily connected to such an external video source device will be a great advantage.

However, a general digital television has a problem in that an image of an external image source apparatus cannot be displayed on a digital television because the screen display format is different from that of an external image source apparatus such as a digital set-top box or a computer.

Accordingly, the present invention has been made to solve such a problem, and in digital television, by converting the video signal output from an external video source device such as a digital set-top box, a computer, etc. into a display method required by the digital television, It is an object of the present invention to provide a device for connecting an external image source device of a digital television which can easily connect an external image source device with a digital television.

Fig. 1 is a block diagram schematically showing a preferred embodiment of an external video source device connecting device of a digital television according to the present invention.

<Description of the code | symbol about the principal part of drawing>

10: YUV conversion / synchronous separation unit 20: RGB changing unit

25: multiplexer 30: analog / digital converter

35 control unit 40 format converter

In order to achieve the above object, in the digital television, the YUV conversion / synchronization separation unit includes a digital set-top box including a luminance signal (Y), a color difference signal (Pb, Pr), and horizontal and vertical synchronization signals in a digital form. After separating the horizontal and vertical sync signals from the output, convert the YPbPr signal into a YUV signal, and the RGB converter converts the YUV signal converted by the YUV conversion / sync separator into an RGB signal which is an analog signal. The RGB signal converted by the RGB converter and the RGB signal input from the computer are converted into digital signals, and then the format converter converts the RGB signals output from the analog / digital converter into the digital set-top box. It is characterized by changing to a certain type of format required for digital television according to the computer and the computer.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a block diagram schematically showing a preferred embodiment of an external video source device connecting device of a digital television according to the present invention.

Referring to FIG. 1, first, the YUV conversion / synchronization separation unit 10 is configured at the output of the digital set-top box 1 composed of digital luminance signals Y, color difference signals Pb and Pr, and horizontal and vertical synchronization signals. After separating the horizontal and vertical sync signals, the YPbPr signal is configured to be converted into a YUV signal. Here, the YUV signal refers to a signal obtained by dividing the Y-R and Y-B color difference signals by a scaling factor value to prevent overmodulation during AM modulation.

In addition, the RGB converter 20 is connected to an output terminal of the YUV converter / synchronous separator 10 to convert the YUV signal converted by the YUV converter / synchronous separator 10 into an RGB signal.

The multiplexer 25 receives the RGB signal converted by the RGB converter 20 and the RGB signal input from the computer 2 and selectively outputs the RGB signal received by the signal selection command.

In addition, the analog-to-digital converter 30 receives the output of the multiplexer 25 to perform analog-to-digital conversion.

Meanwhile, the format converter 40 identifies whether the output of the analog / digital converter 30 is an RGB signal converted by the RGB converter 20 or an RGB signal input from the computer 2 according to a source identification signal. Then, in each case, the format is changed to a predetermined format required by digital television.

At this time, the control unit 35 controls to select one of the RGB signal converted by the RGB converter 20 and the RGB signal input from the computer 2 by applying a signal selection command to the multiplexer 25. The source identification signal is applied to the format converter 40 to determine whether the output of the analog / digital converter 30 is the RGB signal converted by the RGB converter 20 and the RGB signal input from the computer 2. Control to identify. So, if you select computer input 1024 Output at 720 60Hz VESA and set-box input, 1280 It outputs in 720 format and inputs it to the digital television format converter 110.

Hereinafter, the operation of the preferred embodiment of the external video source device connection device of the digital television according to the present invention will be described in detail with reference to FIG.

First, a case in which the YPbPr signal is applied from the digital set top box 1 will be described.

When the output of the digital set-top box 1 consisting of the digital luminance signal Y, the color difference signals Pb and Pr, and the horizontal and vertical synchronizing signals is applied, the YUV conversion / synchronization separation unit 10 is connected to the digital set-top box ( After separating the horizontal and vertical sync signals at the output of 1), convert the YPbPr signal to a YUV signal.

When the converted YUV signal is input from the YUV conversion / synchronization separation unit 10 to the RGB conversion unit 20, the RGB conversion unit 20 converts the YUV signal into an RGB signal, which is an analog signal, and applies it to the multiplexer 25. do.

Accordingly, when the multiplexer 25 selects and outputs the RGB signal converted by the RGB converter 20 as a signal selection command provided from the controller 35 is applied to a high state, the multiplexer 25 then selects the multiplexer 25. The analog / digital converter 30 receiving the output converts the RGB signal output from the RGB converter 20 into a digital signal by analog / digital conversion and outputs the digital signal to the format converter 40. The format converter 40 controls the controller. As the source identification signal is applied to the high state from (35), it is recognized that the input RGB signal of the digital form is applied from the digital set-top box (1) and 1280 It converts to 720 format and outputs it to the digital television format converter 110.

Due to this, the digital television format converter 110 has 1280 The 720 format is converted to a format required by the display apparatus 120 (for example, FLCD: 1280 × 768P, digital television: 720 × 480P, 1280 × 720P, 1920 × 1080I), and then output to the display apparatus 120. It plays a role of display. Here, P and I mean progressive scan and interlace scan, respectively.

Next, a case where the RGB signal is applied from the computer 2 will be described.

When an analog RGB signal is input from the computer 2 to the multiplexer 25, the multiplexer 30 outputs the RGB output from the computer 2 as a signal selection command provided from the control unit 35 is applied in a low state. Select and output the signal. Subsequently, the analog / digital converter 30 receiving the output of the multiplexer 25 converts the RGB signal output from the computer 2 into a digital signal by analog / digital conversion and outputs the digital signal to the format converter 40, and then the format converter. As the source identification signal is applied in the low state from the control unit 35, the 40 recognizes that the input RGB signal of the digital form is applied from the computer 2, and 1024. It is converted to 720 60Hz VESA standard format and output to the digital television format converter 110.

Due to this, the digital television format converter 110 is 1024 Convert the 60Hz VESA standard format of 720 to the format required by the display device 120 (e.g., FLCD: 1280 × 768P, Digital TV: 720 × 480P, 1280 × 720P, 1920 × 1080I), 120) to output and display. Here, P and I mean progressive scan and interlace scan, respectively.

Therefore, the YPbPr signal output from the digital set-top box 1 and the RGB signal output from the computer 2 can be converted into a display system of digital television and displayed in an image format appropriate for each display device.

On the other hand, when the output of the digital set-top box 1 or the computer 2 is not applied, it is obvious that the digital television format converter 110 performs format conversion on the output of the video decoder 100. That is, when the video signal is separated from the bitstream demodulated by the channel decoder 90, and the video stream is applied to the video decoder 100, the video decoder 100 performs decoding according to a preset decoding scheme to perform digital decoding. To the television format converter 110.

Such a digital television can be easily connected to a device or a DVD providing an NTSC source.

The YPbPr signal, YUV signal, and RGB signal used herein are based on YPbPr color coordinates, YUV color coordinates, and RGB color coordinates, respectively. It is well known that it can be easily converted through a matrix operation by a conversion equation.

Terminologies used herein are terms defined in consideration of functions in the present invention, which may vary according to the intention or customs of those skilled in the art, and the definitions should be made based on the contents throughout the present application. will be. Although specific embodiments of the invention have been described and illustrated, it will be apparent that the invention may be embodied in various modifications by those skilled in the art.

In addition, since the present invention has been described through the preferred embodiment of the present invention, in view of the technical difficulty aspects of the present invention, those having ordinary skill in the art can easily be different from another embodiment of the present invention. As modifications may be made, it is obvious that both the embodiments and modifications cited in the above description belong to the appended claims.

As described above, according to the present invention, an YPbPr signal output from a digital set-top box and an RGB signal output from a computer can be converted into a display method of a digital television and displayed in an image format appropriate for each display device. .

Claims (2)

In digital television: Separating the horizontal and vertical synchronization signal from the output of the digital set-top box consisting of a digital luminance signal (Y), color difference signals (Pb, Pr), horizontal and vertical synchronization signals, and then converts the YPbPr signal into a YUV signal. A YUV conversion / synchronization separator; An RGB converter for converting the YUV signal converted by the YUV converter / synchronous separator into an RGB signal; A multiplexer for receiving the RGB signal converted by the RGB converter and the RGB signal input from the computer and selectively outputting the RGB signal according to a signal selection command; An analog / digital converter (ADC) configured to receive an output of the multiplexer and perform analog / digital conversion; After identifying whether the output of the analog-to-digital converter is an RGB signal converted by the RGB converter or an RGB signal input from the computer according to a source identification signal, in each case, a predetermined type of format required by digital television A format converter for changing to; And Applying the signal selection command to the multiplexer controls to select one of the RGB signal converted by the RGB converter and the RGB signal input from the computer, and applies the source identification signal to the format converter to apply the analog / And a control unit for controlling an output of the digital converter to identify one of an RGB signal converted by the RGB converter and an RGB signal input from the computer. The method of claim 1, wherein the predetermined form of the format, The RGB signal of the digital set top box is 1280 720 format, the computer's RGB signal is 1024 A device for connecting an external video source device of a digital television, which is 720 60Hz VESA standard format.