KR100491442B1 - Apparatus for restoring a horizontal active signal and synchronizing signal - Google Patents

Abstract

The number of clock signals in one horizontal line is set using the header and resolution information of the video signal received from the physical device that cannot transmit the clock signal from the source device, and the horizontal synchronization signal and the vertical active signal according to the count value of the clock signal. Restore it.

The serial / parallel converter converts the serial data of the optical signal received by the optical signal receiver into parallel data, and the decoder decodes and converts the 10-bit parallel data into 8-bit parallel data. The video signal packet is processed to separate the headers, and the video signal characteristic packet is processed to recognize the resolution information of the video signal. The clock signal generator generates a clock signal according to the recognized resolution information. In addition to counting, the maximum count value control unit sets the maximum count value of the counter, and sets the maximum count value to the maximum count value set by the video signal processor and the maximum count value set by the counter within the header period. It is variable depending on whether it counts, and preset value according to resolution information. As the counter counts, the horizontal active signal / synchronization signal generator generates a horizontal active signal and a horizontal synchronization signal.

Description

Apparatus for restoring a horizontal active signal and synchronizing signal}

According to the present invention, a display device receives an image signal transmitted by a predetermined source device such as a set-top box through a physical medium that cannot transmit a clock signal such as an optical fiber, and sets the number of clock signals of one horizontal line. The present invention relates to a horizontal active signal / synchronous signal recovery apparatus for recovering a horizontal active signal and a horizontal synchronization signal.

With the development of electronic technology, many flat panel display (FPD) devices have been developed. In display devices such as television receivers and monitors, display screens displaying predetermined images are bulky and thin and light instead of heavy cathode ray tubes. Increasingly, flat panel display elements are adopted.

A flat panel display element is divided into the element using an inorganic substance, and the element using an organic substance based on the substance used. Examples of devices using inorganic materials include plasma display panels (PDPs) using PL (photo luminescence) and field emission display (FED) devices using cathode luminescence (CL), and organic materials are used. Examples of the device include a liquid crystal display element (LCD), an organic EL display element, and the like, which are widely used in various fields.

Among these flat panel display elements, PDP has high brightness and high luminescence efficiency, wide viewing angle, can be manufactured at a relatively low manufacturing price compared to other flat panel display elements, and has excellent heat and cold resistance and earthquake resistance characteristics. Because of the advantages of easy implementation of full color and light weight, PDP has been widely adopted as a display screen in display devices such as television receivers and monitors with the advent of large PDPs. In addition, since the display device adopting the PDP as the display screen is light in weight and thin in thickness, it is being developed as a wall-mount type.

As such, in order to input a video signal and an audio signal output from a source device such as a set top box to a display device employing a PDP, the display device outputs video and audio. Are connected to each other with a predetermined cable so that the video and audio signals of the source device are transmitted to the display device via the cable, and the display device and the source device transmit the predetermined control signal to each other through the cable. have.

1 is a diagram illustrating a connection relationship between a conventional display device and a source device as an example. Here, reference numeral 100 denotes, for example, a wall-mounted display device such as a wall-mounted monitor or wall-mounted television receiver using a PDP as a display screen.

Reference numeral 110 denotes a digital apparatus such as a digital VTR (Video Tape Recorder) or a DVD (Digital Video Disc) player that reproduces a predetermined playback medium and outputs a transport packet stream of a digital video signal and an audio signal. Reference numeral 120 is an analog device such as a VTR or computer system that reproduces a playback medium such as a video tape and outputs an analog video signal and an analog audio signal.

Reference numeral 130 receives a digital broadcast signal, selectively receives a transmission packet stream output from the digital device 110 and analog video and audio signals output from the analog device 120, and selectively switches the converted signal. A source device such as a set top box to transmit to the display device 100.

In the conventional apparatus having such a configuration, the plurality of digital devices 110 and the source device 130 are connected by, for example, an IEEE 1394 cable or the like, and the digital device 110 reproduces a predetermined playback medium or the like. A signal and an audio signal are output as a transmission packet stream, and the output predetermined transmission packet stream is transmitted to the source device 130 through an IEEE 1394 cable or the like.

In addition, the analog device 120 and the source device 130 are connected by a coaxial cable. The analog device 120 reproduces a predetermined playback medium and outputs an analog video signal or an analog R, G, B signal, and an analog audio signal. The generated analog video signal or the analog R, G, and B signals and the analog audio signal are transmitted to the source device 130 through a coaxial cable.

The source device 130 receives a digital broadcast signal through an ATSC (Advanced Television Systems Committee) tuner or the like, transmits a packet packet stream of the received digital broadcast signal, and a transmission packet input from the digital device 110. Converts the stream into analog video signals and analog audio signals, selectively converts the converted analog video signals and analog audio signals, and analog video signals and audio signals input from the analog device 120 according to a user's selection And transmit it to the display device 130.

Here, the source device 130 transmits the analog R, G, B signals and the audio signals of the L and R channels to the display device 100 through the respective cables or through the dedicated integrated cable, the analog R, G, The B signal and the analog audio signals of the L channel and the R channel are transmitted to the display device 100.

In addition, a separate control / response cable is connected between the display device 100 and the source device 130, and a predetermined control signal and a response signal according to the control signal are transmitted to each other through the control / response cable. have.

However, since the display device 100 and the source device 130 are connected by a predetermined cable, the above-described conventional technology is installed when the display device 100 is mounted on a wall as a wall type and the source device 130 is installed on a shelf or the like. A cable for transmitting analog R, G, B signals and an analog audio signal, a cable for transmitting control signals and response signals, etc. are exposed to a wall exposed between the display device 100 and the source device 130. The exposed cable is thick and does not look good.

Therefore, in Patent Application No. 2002-5941, filed by the present applicant, the display device and the source device are connected with an optical fiber that is hardly discernible from a distance because of a thin thickness, and the source device is a video signal, an audio signal, a control signal, an image. Signal characteristics, voice signal characteristics, and the like are transmitted as optical signals to the display device through the optical fiber, and the display devices receive and process the optical signals.

In order for the source device to transmit a video signal, an audio signal, a control signal, an image signal characteristic, and an audio signal characteristic to the display device as an optical signal through an optical fiber, 8-bit data is converted into 10-bit data so as to be suitable for transmission of the optical signal. In addition, since the optical signal cannot be transmitted in parallel data, the optical signal must be converted into serial data in a predetermined format and transmitted.

Therefore, the source device selects and encodes the video signal, the audio signal, the control signal, the video signal characteristic and the audio signal characteristic in the order of a predetermined format, converts 8-bit parallel data into 10-bit data, and encodes the 10-bit data. After converting the parallel data of the serial data to the optical signal is transmitted through the optical fiber.

2 is a diagram illustrating a format structure of serial data in which a source device transmits a video signal, an audio signal, a control signal, a video signal characteristic, and an audio signal characteristic to a display device as a packet. Here, reference numeral 200 denotes a video signal packet having the largest data capacity. Each of the video signal packets 200 includes a video signal of one horizontal line, and in front of the video signal, the blanking header is provided when the video signal is a blanking section, and the video signal is active. Active header is provided, and the tail is continuously provided after the video signal.

The audio signal packet 202, the control signal packet 204, the video signal characteristic packet 206, and the audio signal characteristic packet 208 each having a header and a tail before and after each of the video signal packets 200 are provided. To be located. Here, the arrangement order of the audio signal packet 202, the control signal packet 204, the video signal characteristic packet 206 and the audio signal characteristic packet 208 may be changed.

The serial data of this format is encoded so that 8-bit data is converted into 10-bit data suitable for the transmission of the optical signal, and is modulated by the optical signal transmitter into the optical signal and then transmitted to the display device 100 through the optical fiber.

In this case, an optical fiber, which is a physical medium for transmitting an optical signal, may not transmit a clock signal used when the source device 130 processes an image signal to the display device 100.

The display device 100 may determine an approximate frequency of the clock signal to restore the video signal through the video signal characteristic packet received from the source device 130 even if the clock signal is not input from the source device 130. Although the clock signal may be generated at the determined approximate frequency, the clock signal may not be generated exactly the same as the clock signal used by the source device 130.

Therefore, when the display device 100 receives an image signal through a physical medium such as an optical fiber that cannot receive a clock signal from the source device 130, the number of clock signals within one horizontal synchronizing signal period is set correctly. The horizontal synchronization signal and the horizontal active signal must be restored and used according to the clock signal.

Therefore, it is an object of the present invention to receive an optical signal transmitted by a source device and to accurately set the number of clock signals in one horizontal synchronization period by using the header of the image signal packet in the received optical signal, and the horizontal active signal and horizontal synchronization. The present invention provides a horizontal active signal / synchronous signal recovery apparatus for recovering a signal.

The horizontal active signal / synchronization signal recovery apparatus of the present invention having the above object is characterized in that an optical signal receiver receives an optical signal transmitted from a source device through an optical fiber, and serial / parallel serial data of an optical signal received by the optical signal receiver. The converter converts the parallel data output by the serial / parallel converter, and converts the 10-bit parallel data into 8-bit parallel data by decoding the parallel data output from the serial / parallel converter. Processing the packet to separate the header and processing the video signal characteristic packet to recognize the resolution information of the video signal, the clock signal generator generates a clock signal according to the resolution information recognized by the video signal processor, the clock generator generated The counter counts a clock signal, and the resolution information recognized by the image signal processor The maximum count value control unit sets the maximum count value of the counter and determines whether the counter counts the set maximum count value within the header period recognized by the video signal processing unit and within the header period. The horizontal active signal / synchronization signal generator generates a horizontal active signal and a horizontal synchronization signal as the counter counts a preset value according to the resolution information recognized by the image signal processor. .

The maximum count value control unit resets the counter every time the header is input for a preset number of times to repeatedly count the maximum count value, and variably sets the maximum count value according to the repeat count result. Adds the maximum count value of the counter by one when the number of times the maximum count value has been completed is equal to or greater than a preset value, and the counter when the number of times the header is input before the counter counts the maximum count value is equal to or greater than the preset value. It is characterized by setting by subtracting the maximum count value by one.

Hereinafter, the horizontal active signal / synchronous signal recovery apparatus of the present invention will be described in detail with reference to the accompanying drawings of FIGS. 3 and 4.

3 is a block diagram showing the configuration of the restoration apparatus of the present invention. As shown therein, an optical signal receiver 300 for receiving an optical signal from a source device through an optical fiber and serial / parallel for converting serial data of the optical signal received by the optical signal receiver 300 into 10-bit parallel data. A converter 320, a decoder 320 for decoding the 10-bit parallel data output from the serial / parallel converter 310 into 8-bit parallel data, and an image signal in the output signal decoded by the decoder 320 A video signal processor 330 for separating the header from the packet and recognizing the resolution information of the video signal as a video signal characteristic packet, and generating a clock signal having a predetermined frequency according to the resolution information recognized by the video signal processor 330. The counter according to the clock generator 340, the counter 350 for counting the clock signal generated by the clock generator 340, and the resolution information recognized by the image signal processor 330. A maximum count value of 350 is set and the set maximum count value is counted, and the maximum count value set by the counter 350 is counted within a period of a header recognized by the video signal processing unit 330. The horizontal active signal and the horizontal synchronization as the counter 350 counts a preset value according to the resolution information recognized by the image signal processing unit 330 and the maximum count value control unit 360 which is variablely set according to whether It consists of a horizontal active signal / synchronization signal generation part 370 which generates a signal.

The horizontal active signal / synchronization signal recovery apparatus of the present invention configured as described above receives an optical signal, which is converted into serial data of a predetermined format from a source device and transmitted through an optical fiber, by the optical signal receiver 300, and serially receives the received optical signal. The serial / parallel converter 310 converts the data into 10-bit parallel data and outputs the converted data. The 10-bit parallel data output by the serial / parallel converter 310 is decoded by the decoder 320 and converted into 8-bit parallel data, and among the output data of the decoder 320, the image signal processor 330 performs an image. By processing the signal packet to separate the header, and processing the video signal characteristic packet to recognize the resolution information of the video signal.

In this case, the resolution information may be recognized using the header. That is, the number of horizontal lines is different depending on the resolution of the video signal, and the video signal processor 330 may count the number of active headers and recognize the resolution information by counting the number of active headers.

The resolution information output from the image signal processor 330 is input to the clock generator 340, the maximum count controller 360, and the horizontal active signal / synchronization signal generator 370.

The clock generator 340 generates a clock signal having a predetermined frequency according to the resolution information input from the image signal processor 330, and the generated clock signal is input to the counter 350 and counted.

Meanwhile, the maximum count value control unit 360 sets the maximum count value of the counter 350 in step 400 according to the resolution information recognized by the image signal processing unit 330, as shown in FIG. 4. In operation 402, it is determined whether a header is input from the image signal processor 330.

When the header is input in step 402, the maximum count value control unit 360 resets the counter 350 in step 404 so that the counter 350 starts counting the clock signal, and step 406 , Add 1 to the number N of times the counter 350 counts the clock signal.

In the next step 408, it is determined whether the counter 350 has counted the set maximum count value. If the maximum count value has not been counted, it is determined whether the header is input from the image signal processor 330 in step 410. Determine whether or not.

In such a state, when the counter 350 is set to the maximum count value set in step 408 before the header is input in this state, the maximum count value control unit 360 returns 1 to the count completion count A in step 412. In step 414, it is determined whether the count signal N of the clock signal is equal to or greater than the preset number. 350 is reset so that the clock signal is counted again, and the operation of adding 1 to the count number N is repeatedly performed.

When the header is input from the image signal processing unit 330 in step 410 before the counter 350 counts the maximum count value, the maximum count value control unit 360 performs the input count of the header in step 416. 1 is added to B), and in step 418, it is determined whether the count number N of the clock signal is equal to or greater than the preset number, and when the count number N is not equal to or greater than the set number, the step ( Returning to 404, the counter 350 resets and counts the clock signal again, and repeats the operation of adding 1 to the count number N.

In this state, when the count number N of counting the clock signal becomes equal to or greater than the set value, the maximum count value controller 360 determines that the counter 350 counts the maximum count value before the header is input in step 420. It is determined whether the number A is greater than or equal to the preset value, and when the number A is greater than or equal to the preset value, the maximum count value is added by one and set in the counter 350 in step 422. When the number of times A is not greater than or equal to a preset value in step 420, the maximum count value control unit 360 inputs a header before the counter 350 counts the maximum count value in step 424. It is determined whether the number B is greater than or equal to the preset value, and if the number of times B of the header is greater than or equal to the preset value, the maximum count value is subtracted by one in step 426 and set to the counter 350. Returning to step 402, the above operation is repeated and the maximum count value of the counter 350 is set.

For example, the counter 350 counts the clock signal until the header is input ten times by setting the count number N of the clock signal to 10, and the counter 350 first before the ten count result header is input. When the number A of counting the maximum count value is six or more times, the maximum count value is increased by 1 and set to the counter 350, and the number of times the header is input before the counter 350 counts the maximum count value ( When B) is six or more times, the maximum count value of the counter 350 is subtracted by one and set to the counter 350.

The horizontal active signal / synchronization signal generator 370 determines a generation count value of a horizontal active signal and a generation count value of a horizontal synchronization signal according to the resolution information recognized by the image signal processing unit 330, and determines the counter. The horizontal active signal is generated as the count value of 350 becomes the generation count value of the horizontal active signal, and the horizontal synchronization signal is generated as the count value of the counter 350 becomes the generation count value of the horizontal synchronization signal.

On the other hand, while the present invention has been shown and described with respect to specific preferred embodiments, various modifications and changes of the present invention without departing from the spirit or field of the invention provided by the claims below It can be easily understood by those skilled in the art. For example, in the above, the source device and the display device use the optical fiber as a physical medium for transmitting the video signal as an example, but in the embodiment of the present invention, the source device and the display device can transmit a clock signal in addition to the optical fiber. When the video signal is transmitted through various physical media that do not exist, it can be simply applied.

As described in detail above, the present invention accurately sets the number of clock signals between one horizontal line by using a signal received through a physical medium that cannot transmit a clock signal, and according to the count value of the clock signal, By restoring the horizontal synchronizing signal, changes in the horizontal synchronizing signal and the vertical synchronizing signal can be minimized. As a result, the image signal can be accurately restored to reproduce a clean image without shaking or noise.

1 is a view showing a connection relationship between a conventional source device and a display device as an example,

2 is a diagram illustrating a format structure of serial data in which a source device transmits a video signal, an audio signal, a control signal, a video signal characteristic, and an audio signal characteristic to a display device as a packet.

3 is a block diagram showing the configuration of the restoration apparatus of the present invention,

4 is a signal flow diagram showing the operation of the maximum count value control unit in the restoration apparatus of the present invention.

* Description of the symbols for the main parts of the drawings *

300: optical signal receiver 310: serial / parallel converter

320: decoder 330: image signal processing unit

340: clock generator 350: counter

360: maximum count value control unit 370: horizontal active signal / synchronization signal generator

Claims (4)

An optical signal receiver for receiving an optical signal from a source device through an optical fiber; A serial / parallel converter for converting serial data of the optical signal received by the optical signal receiver into parallel data; A decoder for decoding the parallel data output by the serial / parallel converter and converting the 10-bit parallel data into 8-bit parallel data; A video signal processor which separates a header from a signal decoded by the decoder and recognizes resolution information of the video signal; A clock signal generator for generating a clock signal according to the resolution information recognized by the image signal processor; A counter for counting a clock signal generated by the clock generator; A maximum count value of the counter is set according to the resolution information recognized by the image signal processor, and the maximum count value in which the counter is set within a header period and a header period in which the image signal processor recognizes the set maximum count value A maximum count value control unit that varies according to whether or not to count the count; And A horizontal active signal / synchronous signal composed of a horizontal active signal / synchronous signal generator for generating a horizontal active signal and a horizontal synchronization signal while determining whether the counter counts a preset value according to the resolution information recognized by the image signal processor. Restoration device. The method of claim 1, wherein the recognition of the resolution information; And recognizing the number of consecutive active headers in the video signal packet. The method of claim 1, wherein the maximum count value control unit; And resetting the counter every time the header is input for a predetermined number of times to repeatedly count the maximum count value, and varying the maximum count value according to the repeat count result. The method of claim 3, wherein If the counter has completed counting the maximum count value before the header is input, the maximum count value of the counter is added by one, and the number of times the header is input before the counter counts the maximum count value is preset. And a maximum count value of the counter is set by subtracting by one if the value is greater than or equal to one.