KR0135483B1 - Cd-rom drive circuit - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

CD ROM Player

2. The technical problem to be solved by the invention

Decode video data stream from CD-ROM driver.

3. Summary of the Solution of the Invention

The CD-ROM driver is provided with a video and audio decoder to output data reproduced from the CD-ROM to the system processing stage in the CD-ROM mode and to operate the video decoder in the video / audio mode to overlay the processed video signal as an overlay of the system. At the same time, it outputs to TV and outputs audio signal processed by audio decoder to audio output terminal.

4. Important uses of the invention

It can be processed directly in the CD-ROM driver without having a separate decoding means, thereby enabling the video-CD player function as a CD-ROM driver.

Description

CD-ROM drive circuit

1 is a block diagram of a CD ROM drive circuit according to the present invention.

2 is a detailed block diagram of the second signal processor of FIG.

* Explanation of symbols for the main parts of the drawings

100: system control unit 200: servo control unit

300: first signal processing unit 400: second signal processing unit

500: interface part 600: amplification part

410: stream buffer 420: video decoder

421: Video memory 422: D / A converter

423: RGB encoder 430: audio encoder

431: Audio memory 432: Multiplexer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CD ROM drive circuit mounted in a system, and more particularly, to a CD ROM drive circuit having a built-in decoder capable of processing compressed audio and video data so as to reproduce compressed video and audio in a CD ROM drive circuit. It is about a circuit.

In general, a CD ROM driver (Compact Disc ROM Driver) is mounted on a system such as a computer and used as an auxiliary storage device. That is, since the CD ROM can record a large amount of data, its field of use is expanding. Also, the implementation of a multimedia system through a computer is becoming common, and CD ROM alone cannot satisfy this. In other words, the CD ROM drive circuit incorporated in a system such as a computer should be able to play a CD recorded with compressed audio and video information in addition to the CD ROM. In the related art, these functions have been implemented on a system without being implemented in a CD-ROM drive, and thus, the performance of the system is degraded, and a complicated configuration requires a disadvantage in terms of control method and cost.

It is therefore an object of the present invention to provide a circuit capable of processing compressed audio and video using a CD ROM drive circuit mounted in the system.

It is another object of the present invention to provide a CD ROM drive circuit capable of reproducing audio and video data recorded in MPEG in addition to CD ROM playback by adding an MPEG decoder to the CD ROM drive circuit.

In order to achieve the above object of the present invention, the CD ROM drive circuit of the present invention includes a system controller for controlling an operation mode of the CD ROM drive circuit according to the CD mode, and a CD rotation and pickup operation under the control of the system controller. A servo control unit, a first signal processing unit which reads information recorded on a CD and processes error correction and decoding operations, and receives decoding data output from the first signal processing unit under control of the system and separates the video data and audio data. And a second signal processor which decodes the separated video data and outputs it to a system or a television, and simultaneously decodes the audio data and outputs it to an audio output line. The CD ROM drive circuit of the present invention having the above configuration has a CD ROM mode. System control unit disables the second signal processing unit so that the first signal processing unit And outputs the CD-ROM data to be processed in the system, the by enabling the second signal processing upon the compressed video or audio information to be reproduced from the CD mode, characterized in that operates to output to the system or outside the system.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the same parts in the figures represent the same reference signs wherever possible.

Many specific details, such as MPEG, etc., are presented in the following description to provide a more general understanding of the invention. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

The term Motion Pictures Expert Group (MPEG) used here is recommended as a standard for compressing data. In the present invention, it is assumed that a CD on which video data and audio data is recorded in the MPEG method is called, and this mode will be referred to as MPEG mode.

FIG. 1 is a schematic diagram of a CD ROM drive circuit according to the present invention in which an MPEG decoder is embedded in a general CD ROM drive circuit. The system controller 100 controls an overall operation mode of a CD ROM drive circuit according to an externally applied CD mode. The servo controller 200 is connected to a spindle motor for rotating the CD and a pickup device for reading information of the CD. The servo controller 200 controls the rotation of the CD and the operation of the pickup under the control of the system controller 100. That is, the servo controller 200 performs a system servo function such as a focusing servo and a tracking servo of the rotation control of the spindle motor and the pickup device. The first signal processor (docoder) 300 is a digital signal processor (Digital Singnal Processor), receives the record information read from the CD, and processes the record information under the control of the system controller 100. The first signal processor 300 error corrects information read from the parity information added during recording in units of blocks. Since the error corrected information is encoded, the first signal processor 300 decodes the data before recording and restores the original data. The interface unit 500 is connected to the data processing unit of the system and applies data output from the first signal processing unit 300 to the system side. The second signal processor 400 is an MPEG decoder and receives decoding information output from the first signal processor 300 and is controlled by the system controller 100. The second signal processor 400 is stopped in the CD ROM mode under the control of the system controller 100. The second signal processor 400 selects the decoding information received by enabling the operation in the MPEG mode as video and audio information, and then selects the selected MPEG method. The first video signal V1 and the second video signal V2 are decoded to be transmitted to the system or television, and the audio information of the MPEG method is decoded and output to the audio output terminal LO or the headphone terminal HP.

Referring to the operation of FIG. 1, the system controller 100 and the second signal processor 400 exchange control signals with an interface signal, and a system MPEG stream is received from the first signal processor 300. Then, the second signal processor 400 receives the MPEG stream, separates it into a video and audio stream, and decodes it. At this time, the decoded first video signal V1 is transmitted to a system such as a computer as RGB data, and in parallel, the video data is converted to the second video signal V2 through a D / A conversion process and an RGB encoding process and then outputted for television output. Is sent to the terminal. The decoded audio data is then multiplexed with the audio line of the CD-ROM via D / A conversion and then sent to the audio output terminals (LO, HP).

FIG. 2 is a block diagram illustrating the detailed block of the second signal processor 400. The stream buffer 410 receives the MPEG stream output from the first signal processor 300 under the control of the system controller 100. FIG. The MPEG stream received by the stream buffer 410 selects and outputs a video stream and an audio stream under system control.

The video decoder 420 is connected to the video stream output terminal of the stream buffer 410 and decodes and outputs an MPEG video stream received under the control of the system controller 100. The video memory 421 stores a video stream received under the control of the video decoder 420. The video memory 421 buffers the video decoder 420 to decode the video stream to generate a first video signal V1 and a second video signal V2. The D / A converter 422 is connected to an output terminal of the video decoder 420 to convert the MPEG decoded first video signal V1 into an analog signal. The RGB encoder 423 is connected to the output terminal of the D / A converter 422, encodes the received analog video signal in RGB format, converts the received analog video signal into the second video signal V2, and outputs the result to the delegate output terminal.

The audio decoder 430 is connected to an audio stream output terminal of the stream buffer 410 and decodes and outputs an MPEG audio stream received under the control of the system controller 100. The audio memory 431 stores an audio stream received under the control of the audio decoder 430. The audio memory 431 buffers the audio decoder 430 to decode the audio stream. The multiplexer 432 outputs the audio signal of the audio decoder 430 and the CD ROM. The multiplexer 432 is selected by the mode signal of the system controller 100 and output to the audio output terminals LO and HP.

As described above, the system controller 100 varies the operation of the CD ROM drive circuit according to the CD ROM mode and the MPEG mode. In the MPEG mode, the system controller 100 controls the operation of the second signal processor 400, which is an MPEG decoder. First, the MPEG stream data output from the first signal processor 300 is temporarily stored in the stream buffer 410 under the control of the system controller 100. At this time, the system controller 100 reads information (time stamp, head information) necessary for selecting audio and video data from the stream data stored in the stream buffer 410, and the video stream is selectively separated according to the read information. The audio stream is separately stored in another area of the stream buffer 410. If the selected video data and audio data are of constant size while the above process is repeated, the system controller 100 controls the stream buffer 410 to transfer the selected video data and audio data to the video decoder 420 and the audio decoder 430, respectively. send.

The video decoder 420 decodes the MPEG video stream output from the stream buffer 410 under the control of the system controller 100. In other words, when the video decoder 420 receives the video stream, the video decoder 420 processes the system control unit 100 in a handshake manner, and the decoding uses a time stamp to synchronize with the decoding operation of the audio stream. Therefore, the video decoder 420 temporarily stores the received video stream in the video memory 421 and reads the stored information under the control of the system controller 100 to perform decoding. The first video signal V1 generated through the above process is synchronized with the television signal by the synchronization signal received from the synchronization generator, and is converted into R, G, and B data for transmission to the overlay of the system. Is sent to the system. In addition, the first video signal V2 transmitted in parallel with the first video signal V1 transmitted to the overlay of the system is applied to the television output terminal through the D / A converter 422 and the RGB encoder 423.

The audio decoder 430 decodes the MPEG audio stream output from the stream buffer 410 under the control of the system controller 100. That is, the audio decoder 430 processes the system stream 100 in a handshake manner when receiving the audio stream, and decoding uses a time stamp to synchronize with the decoding operation of the video stream. Therefore, the audio decoder 430 temporarily stores the received video stream in the audio memory 431, and reads the stored information under the control of the system controller 100 to perform decoding. The output of the audio decoder 432, which is decoded and converted into an analog signal, is applied to the multiplexer 432. At this time, the multiplexer 432 selects and outputs an audio signal reproduced to a CD ROM in the CD ROM mode according to the mode control of the system controller 100, and selectively outputs the output of the audio decoder 432 in the MPEG mode. The audio signal outputting the multiplexer 432 is applied to the line output terminal LO and the headphone output terminal HP.

As described above, the CD-ROM drive circuit according to the present invention can decode MPEG stream information by itself by embedding an MPEG video and audio decoder, and can also apply the decoded video data to a system and display it directly through television. You may. Therefore, it is not necessary to install a separate decoding means for audio and video processing in the system, high performance can be realized with a simple configuration, and there is an effect that a video CD function can be implemented by a CD ROM drive circuit.

Claims (4)

A compact disc drive circuit mounted on a computer, comprising: a system controller for controlling an operation mode of the compact disc drive circuit in accordance with a mode of the compact disc, and a rotation and pickup operation of the compact disc under control of the system controller. A servo control section for controlling, a first signal processing section for reading out data recorded on the compact disc under the control of the system control section and performing error correction and decoding operations, and outputting from the first signal processing section under control of the system control section; And a second signal processor for receiving the stream data, separating the video stream and the audio stream from the stream data at all times, decoding and outputting the separated video stream, and decoding and outputting the separated audio stream. The compact disc When the system controller operates in a data processing mode to output data output from the first signal processor to the data processor, and the compact disc stores video and audio information. And outputting the video signal processed by the second signal processor to the overlay of the computer and simultaneously outputting the audio signal to the audio output terminal. The stream buffer according to claim 1, wherein the second signal processor temporarily stores stream data output from the first signal processor under the control of the system controller, and selectively outputs the stored stream data into a video stream and an audio stream. And video coding means for decoding the video stream output from the stream buffer under the control of the system controller and outputting the video stream to an overlay of the computer, and decoding the audio stream output from the constant stream buffer under the control of the system controller. The compact disc drive circuit of a computer, characterized by comprising audio decoding means for outputting to the audio output terminal of the. A CD ROM drive circuit for reproducing a CD storing video and audio information compressed in a CD ROM and MPEG system, the CD ROM drive circuit comprising: a system controller for controlling an operation mode of the CD ROM drive circuit according to the CD mode; Servo control unit for controlling the rotation of the CD and operation of the pickup device under control, a first signal processing unit for error correction and decoding and outputting a stream read from the CD under control of the system control unit, and control of the system control unit. Receiving MPEG stream data from the first signal processing unit to select an MPEG video stream and an MPEG audio stream, and decode the MPEG video stream to generate a first video signal and a second video signal, and simultaneously receive the MPEG audio stream. And a second signal processor to decode and generate an audio signal to control the system. In the CD ROM mode, the CD ROM data outputting the first signal processor is output to the data processor, and in the MPEG mode, the first video signal generated by operating the second signal processor is output as an overlay of the system. And a second video signal to a television output terminal, and outputs an audio signal to an audio output terminal. 5. The method of claim 4, wherein the second signal processing unit stores the MPEG stream data output from the first signal processing unit under the control of the system control unit, and selects the stored MPEG stream data into the MPEG video stream and the MPEG audio stream. A first video signal is generated by decoding an output stream buffer and an MPEG video stream outputted from the stream buffer under the control of the system controller, and outputting the first video signal as an overlay of the system. Video encoding means for converting a signal into an analog signal and then encoding the RGB signal and outputting the second video signal to a television output stage, and decoding the MPEG audio stream output from the stream buffer under the control of the system controller to output the audio of the system. Comprising audio decoding means for output to the terminal CD ROM drive circuit of computer made with gong.