KR19980027706A - Compact disc player for improved skipping - Google Patents

Abstract

The present invention relates to a compact disc player for skipping improvement, in particular, a high speed data pickup step of picking up data at a predetermined high speed than the normal playback speed at the time of initial playback; Writing the data picked up at the predetermined high speed into a buffer memory; Monitoring the buffer memory and branching to the high speed data pickup step if not full of data, picking up data at the normal playback speed if full with data, and writing the picked up data into the buffer memory; Outputting data written in the buffer memory at the normal reproduction speed; Monitoring the buffer memory to determine if data storage is reduced below a predetermined value; And if the data storage amount decreases below a predetermined value, branching to the high speed data pickup step, and if the data storage amount is higher than or equal to the predetermined value, continuously reproducing.

Therefore, in the present invention, by adjusting the rotational speed of the spindle motor according to the storage state of the buffer memory, that is, the playback speed, the data is constantly reproduced by decoding the data at the normal speed from the buffer memory storing the predetermined pickup data even when skipping occurs. This can reduce the regeneration noise.

Description

Compact disc player for improved skipping

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compact disc player for skipping improvement, and more particularly, by adjusting a data reproduction speed according to a data storage state of a buffer memory using a buffer memory that temporarily stores data when data is reproduced. The present invention relates to a compact disc player for skipping improvement that can eliminate regeneration noise caused by skipping.

1 is a block diagram for explaining an embodiment of a conventional compact disc player.

The compact disc player includes a spindle motor 10, an optical pickup unit 20, a waveform shaping unit 40, a digital signal processing unit 60, and a servo unit 80 that rotates the optical disc a as shown in the drawing. The decoder 100 includes a video output unit 120, an audio output unit 140, and a controller 140.

The compact disc player configured as described above operates as follows.

Focus servo in response to the control command signal provided from the control unit 10, that is, the microcomputer and the servo control signal output from the optical pickup unit 40, that is, the address information signal of the position and the control signal provided from the digital signal processing unit, The servo unit 80 composed of a tracking servo and a rotating servo provides driving signals to the spindle motor 10 and the optical pickup 20. The drive signals rotate the spindle motor 10 at a normal speed, and the optical pickup 40 focuses on the surface of the optical disc a to detect the amount of light reflected from the reflective surface of the optical disc a. Is done. After the picked-up data is shaped into a digital signal by the waveform shaping unit 40, the digital signal processing unit 60 detects subcoding to cause the optical pickup 20 in the servo unit 80 to skip an error. The control signal is generated to return to the position, and the error of the pickup data is corrected and sent to the decoding unit 100, that is, the MPEG decoder. Then, the decoding unit 100 separates the decompressed decompression data into audio and video signals and outputs the decompressed data. In response to the output control signal of the controller 160, the video output unit 120 receives a digital video signal and outputs a video signal V converted into an analog signal, and the audio output unit 140 outputs a control signal of the controller. In response, the digital audio signal is converted into an analog signal and output.

However, when a skipping error occurs due to the micro-vibration of the optical disk during the above-described reproducing operation, the digital signal processing unit controls the servo unit to return the optical pickup to the track position where the error occurs and perform the re-pickup. During this repickup period, there is a problem of reproducing blank space, and undesired reproducing noise caused by reproducing data being cut off during play.

An object of the present invention is to use a buffer memory to temporarily store data when the data is reproduced in order to solve the above problems by adjusting the data playback speed according to the data storage state of the buffer memory, skipping that can occur during data pickup (Skipping) The present invention provides a compact disc player for skipping that can eliminate regeneration noise due to

In order to solve the above problems, an apparatus of the present invention includes a spindle motor for rotating an optical disk; An optical pickup for picking up data from the optical disk; A waveform shaping unit for waveform shaping the signal picked up by the optical pickup; A digital signal processing unit for digitally processing the signal shaped by the waveform shaping unit and outputting reproduction data; A servo unit for controlling the rotational speed of the spindle motor and the focusing and tracking of the optical pickup in response to the servo control signals provided from the digital signal processing unit and the waveform shaping unit; A buffer memory which receives the reproduction data output from the digital signal processor and outputs the first-in first-out method; A decoding unit for reading and decoding the playback data from the buffer memory at a normal playback speed and outputting video data and audio data; A video output unit which inputs the video data to output a video signal; An audio output unit configured to input the audio data to output an audio signal; And at the beginning of regeneration, rotate the spindle motor at a higher speed than the normal speed to store regeneration data at high speed in the buffer memory. When the buffer memory is filled with the playback data, the spindle motor is rotated at the normal speed to store the playback data at the normal speed, and the optical pickup skips the track of the optical disk by external vibration. When the amount of the reproduction data stored in the buffer memory is reduced below a predetermined value, the servo motor, the digital signal processing unit, the buffer memory and the decoding unit are controlled so that the spindle motor rotates at high speed until the buffer memory is filled with the reproduction data again. It characterized in that it comprises a control unit.

In order to solve the above problems, the method of the present invention includes a high-speed data pickup step of picking up data at a predetermined high speed than the normal playback speed at the time of initial playback; Writing the data picked up at the predetermined high speed into a buffer memory; Monitoring the buffer memory and branching to the high speed data pickup step if not full of data, picking up data at the normal playback speed if full with data, and writing the picked up data into the buffer memory; Outputting data written in the buffer memory at the normal reproduction speed; Monitoring the buffer memory to determine if data storage is reduced below a predetermined value; And if the data storage amount decreases below a predetermined value, branching to the high speed data pickup step, and if the data storage amount is higher than or equal to the predetermined value, continuously reproducing.

1 is a block diagram illustrating a conventional embodiment.

Figure 2 is a block diagram for explaining an embodiment of a skipping prevention apparatus according to the present invention.

Figure 3 is a flow chart for explaining an embodiment of the skipping apparatus according to the present invention.

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

2 is a block diagram illustrating an embodiment of a compact disc player for skipping improvement according to the present invention.

The compact disc player includes a spindle motor 10 for rotating the optical disc a, an optical pickup 20 for picking up data from the optical disc a, and a waveform for waveform shaping the signal picked up by the optical pickup 20. A servo provided from the shaping section 40, the digital signal processing section 60 for digitally processing the signal shaped by the waveform shaping section 40, and outputting reproduction data, and the digital signal processing section 60 and the optical pickup 20. In response to the control signal, the servo unit 80 for servo-controlling the rotational speed of the spindle motor 10 and the focusing and tracking of the optical pickup 20 and the reproduction data output from the digital signal processing unit 60 are received first-in-first-out. A buffer memory (100) for outputting in a FIFO method, a decoding unit (120) for outputting video data and audio data by reading and decoding playback data from the buffer memory (100) at a normal playback speed, and the video data mouth Video output unit 140 for outputting a video signal, an audio output unit 160 for inputting the audio data to output an audio signal, and at the initial stage of reproduction, the spindle motor 10 is rotated at a higher speed than the normal speed The playback data is stored at high speed in the buffer memory 100. When the playback data is filled in the buffer memory 100, the spindle motor 10 is rotated at the normal speed to store the playback data at the normal speed in the buffer memory 100, and the optical pickup 20 is driven by external vibration. When the amount of playback data stored in the buffer memory 100 is reduced to a predetermined value or less due to the phenomenon of skipping tracks of the optical disk, the spindle motor 10 is operated at high speed until the buffer memory 100 is filled with the playback data again. The control unit 180 controls the servo unit 80, the digital signal processing unit 60, the buffer memory 120, and the decoding unit 120 to rotate.

The overall operation of the compact disc player configured as described above will be described with reference to the flowchart of FIG. 3 as follows.

The control unit 180, that is, the servo unit 80 consisting of a focus servo, a tracking servo, and a rotation servo in response to a control command signal provided from a microcomputer and an address information signal relating to a synchronization signal and a position output from the optical pickup unit 40. ) Provides driving signals to the spindle motor 10 and the optical pickup 20. By the drive signals, the spindle motor 10 rotates at the normal speed or higher than the normal speed according to the data receiving state of the buffer memory 100, and the optical pickup 20 is reflected from the optical disk a by the focusing operation. The data pick-up is performed by detecting the amount of light.

If the buffer memory 100 is initially empty, the spindle motor 10 rotates at a high speed, that is, twice the normal playback speed so that data can be quickly accessed from the optical disc a. The analog data signal picked up at high speed by the optical pickup 20 is formed by the waveform shaping unit 60 as a digital signal, and the digital signal output by the waveform shaping unit 60 is the digital signal processing unit 100. That is, it is passed to the DSP.

The digital signal processing unit 100 detects subcoding of the digital signal, checks whether an error due to skipping has occurred in the picked-up data, and causes the servo unit 80 to perform an optical pickup when an error due to skipping occurs. (20) is returned to the track at the point where the error occurred so that the data is repicked at high speed.

On the other hand, when there is no skipping error in the picked-up data, the data that has undergone digital signal processing is filled in the buffer memory 100 in a first-in, first-out manner. At this time, the controller 180 monitors the buffer memory 100 to confirm whether the current data storage state is full, and generates a control signal to the servo unit 20 to convert the rotational speed of the spindle motor 10 to the normal regeneration speed. Do it. From this point, data is picked up at normal playback speed.

In the state where the buffer memory 100 is full, the decoding unit 120 takes data of the buffer memory 100 at a normal playback speed in response to a control signal of the controller 180, decompresses the data, and decompresses the data. The decompressed data is separated into a video signal and an audio signal, and each signal is output to the video output unit 140 and the audio output unit 160.

Then, the video output unit 140 and the audio output unit 160 convert the decompressed digital signals into analog signals in response to control signals from the controller, and then output them through the video and analog output terminals V and A. Playback takes place.

When skipping occurs in the above-described operation process, the data storage amount of the buffer memory 100 naturally decreases, and when the data storage amount decreases below a predetermined value, the spindle motor 10 is again controlled to rotate at a high speed so that the buffer memory 100 ) Is filled with playback data again. Such operations are repeatedly performed according to the data storage state of the buffer memory 100.

Therefore, as described above, in the present invention, a buffer memory is provided between the digital signal processing unit and the decoding unit, and the rotation speed of the spindle motor is adjusted according to the storage state of the buffer memory, that is, the reproduction speed is adjusted, so that a predetermined pickup occurs even when skipping occurs. Since the data can be decoded and reproduced constantly from the buffer memory storing the data, the reproduction noise can be reduced.

Claims (3)

A spindle motor for rotating the optical disk; An optical pickup for picking up data from the optical disk; A waveform shaping unit for waveform shaping the signal picked up by the optical pickup; A digital signal processing unit for digitally processing the signal shaped by the waveform shaping unit and outputting reproduction data; A servo unit for controlling the rotational speed of the spindle motor and the focusing and tracking of the optical pickup in response to the servo control signals provided from the digital signal processing unit and the waveform shaping unit; A buffer memory which receives the reproduction data output from the digital signal processor and outputs the first-in first-out method; A decoding unit for reading and decoding the playback data from the buffer memory at a normal playback speed and outputting video data and audio data; A video output unit which inputs the video data to output a video signal; An audio output unit configured to input the audio data to output an audio signal; And at the beginning of regeneration, rotate the spindle motor at a higher speed than the normal speed to store regeneration data at high speed in the buffer memory. When the buffer memory is filled with the playback data, the spindle motor is rotated at the normal speed to store the playback data at the normal speed, and the optical pickup skips the track of the optical disk by external vibration. Control unit for controlling the servo unit, the digital signal processing unit and the buffer memory so that the spindle motor is rotated at a high speed until the buffer memory is filled with the reproduction data again when the amount of the reproduction data stored in the buffer memory is less than a predetermined value Compact disc player for skipping characterized in that it comprises a. The compact disc player as claimed in claim 1, wherein the buffer memory has a size capable of storing critical playback data that does not generate playback noise when skipping occurs. A high-speed data pickup step of picking up data at a predetermined high speed than the normal playback speed at the start of playback; Writing the data picked up at the predetermined high speed into a buffer memory; Monitoring the buffer memory and branching to the high-speed data pickup step if it is not filled with data, picking up data at the normal reproduction speed if filled with data, and writing the picked up data into the buffer memory; Outputting data written in the buffer memory at the normal reproduction speed; Monitoring the buffer memory to determine whether the amount of data storage is reduced below a predetermined value; And branching to a high speed data pick-up step when the data storage amount decreases below a predetermined value, and continuously executing normal playback when the data storage amount is above a predetermined value. Disc player.