KR100563683B1 - Playback speed control method according to defect of optical disc - Google Patents

Abstract

The present invention relates to an optical disc player, in which the defect generation area is detected when the optical disc is inserted, the physical signal of the entire area of the disc is scanned to detect and store the defect occurrence area, and then at constant speed playback. By controlling the low-speed playback to be performed at, the repetitive playback operation can be prevented in the defect generation area, thereby reducing the time required for the repeated playback and reproducing speed according to the defect of the optical disc eliminating unnecessary forward / reverse tracking operations. A method of controlling a play speed according to a defect of an optical disc, which is an embodiment of the present invention, comprises: a step of detecting a normal synchronous signal in a play track while playing a disc at random intervals when the disc is inserted; Storing an area corresponding to a playback track position as a defective area according to the normal synchronization detection; After step 2, step 3 of comparing the current playback track position with the stored defective area while performing constant speed playback; And four steps varying from the constant speed playback to the slow playback according to the comparison result, which is required to switch the operation to the slow playback after several repetitive playback operations for checking the defective area of the disc and for precise playback. By shortening the time, a faster reproducing operation is achieved, as well as a useful invention that can perform a more stable tracking operation by eliminating the forward / reverse tracking operation required during the repetitive reproducing operation.

Description

Playback speed control method according to defect of optical disc

The present invention relates to a method of controlling a playback speed according to a defect of an optical disc. More specifically, the present invention relates to a method of controlling a playback speed. The present invention relates to a playback speed control method according to a defect of an optical disc capable of a faster playback operation by controlling the low speed playback to be performed immediately in the defect generation area during constant speed playback after storage.

A typical optical disc player, as shown in FIG. 1, has a spindle motor 3 for rotating the optical disc 1 at a constant speed, and an optical pickup for reading out signals recorded on the optical disc. (2), a sled motor (4) for moving the optical pickup in the radial direction of the optical disc, a driver (8) for driving the spindle motor and the sled motor, A filter shaping part 5 for filtering the recording signal of the read optical disc and outputting it as an RF (Radio Frequency) signal, and a synchronization separating part 6 for separating a sync signal from the filtered RF signal; And a digital signal processor (DSP) 9 which processes the RF signal into a digital signal according to the separated synchronization signal, and decodes the signal processed digital signal and outputs the original video or audio signal. MPEG decoder 10 and the optical pickup and driver A servo unit 7 for controlling Servo operation, a level detector 13 for detecting the RF output level of the filter shaping unit, and a disc defect are determined according to the detected RF level to control the servo unit. It comprises a microcomputer 11 and a memory 12 for storing data necessary for the control operation.

The reproduction speed control operation according to the conventional optical disc defect applied to the general optical disc player will be described in detail with reference to FIGS. 1 and 3 as follows.

First, the spindle motor 3 is rotated at a constant speed and about 3,000 rpm in accordance with a disc insertion and a user's regeneration key input to perform a regeneration operation (S10). (RFd) (S12), and it is determined whether or not the detected RF level (RFd) is included in a predetermined range (RFr1 to RFr2) (S13). As a result of the determination, if it is included in a predetermined range (RFr1 <RFd <RFr2), the constant speed reproduction state is maintained, but if it is out of the predetermined range (RFD <RFr1 or RFD> RF2), it is determined as a read error. In this case, a series of repetitive operations (Retry) operations as described above (S10 ~ S13) is performed, wherein the number of repetitions is cumulatively increased (Retry number >> + + 1).

When the cumulative increase in the number of repetitions exceeds a predetermined number (N times) (S14), the drive is switched to a low speed regeneration mode for disc defect checking and precision regeneration, that is, the rotational speed of the spindle motor is reduced (approximately 2,000 rpm) to achieve precise precision. Allow regeneration to take place.

However, in the conventional playback speed control operation due to a defect of the optical disc player, after performing the repetitive playback operation a certain number of times or more according to the output level of the RF detected during the playback, the defect checking and the fine playback operation mode, that is, the slow playback mode, are performed. As switching to, the forward / reverse tracking operation for the repeat playback is frequently performed, which causes a long playback time.

Therefore, the present invention was created to solve the above problems, and when the optical disc is reproduced, by switching to the disc defect check and precise playback immediately without the repetitive repetitive operation that takes a long time, a faster playback operation and The purpose is to allow a stable tracking operation to be performed.

According to an aspect of the present invention, there is provided a method of controlling a play speed according to a defect of an optical disc, the method including: detecting a normal sync signal on a play track while playing a disc at random intervals when the disc is inserted; Storing an area corresponding to a playback track position as a defective area according to the normal synchronization detection; After step 2, step 3 of comparing the current playback track position with the stored defective area while performing constant speed playback; And four steps of varying from the constant speed playback to the slow speed playback according to the comparison result.

The playback speed control method according to the defect of the optical disk according to the present invention as described above, when the insertion / playback of the optical disk, the physical signal of the entire disk area is scanned (scan) to detect / store the disk defect occurrence area Then, by performing the low speed regeneration operation immediately in the region where the defect is generated during the constant speed regeneration without additional repetitive regeneration operation, a faster and more stable regeneration operation is achieved.

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

FIG. 2 is a partial configuration diagram of an optical disk player to which a playback speed control method according to a defect of an optical disk according to the present invention is applied. Unlike the general optical disk player of FIG. 1, the conventional level detection unit detects an RF level. (13) is not provided separately, but is further provided in the digital signal processing unit (DSP) 9 to further illustrate a GFS detection unit 29 for detecting a normal synchronization signal (GFS: Good Frame Sync, hereinafter referred to as GFS). Doing.

For reference, the GFS is a normal synchronization signal generated only when a certain number of synchronization signals exist in a predetermined period and at a predetermined period among the digital data streams output from the digital signal processing unit 9. It is used as a signal to detect.

The operation description according to the above configuration will be described in detail with reference to FIGS. 4A and 4B. First, FIGS. 4A and 4B illustrate a flowchart of a method of controlling a play speed according to a defect of an optical disc, which is an embodiment of the present invention. When a disc is inserted, a play operation is performed from an inner circumferential surface to an outer circumferential surface of the disk by switching to a play mode (S100). In this case, the write signal of the read disc is digitally processed (S110), and the GFS signal generated in the process is detected (S120). When the GFS signal is detected in the detecting operation, the current playing area is determined as the disc steady state area and track jumping (S150) is repeated by a predetermined number of tracks (N-Track) without any operation. If the GFS signal is not detected, the area currently being played is determined as a disc abnormal state area, that is, a defect occurrence area, and the corresponding addresses are stored (ADs) (S140). ), Track jump by about 100 tracks. It is preferable to set the fixed track number to about 50 to 150 tracks, which is the size of a disk defect that usually has a high frequency of occurrence.

On the other hand, in this operation, partial reproduction is repeated until the outermost circumferential surface of the disc is detected, and at the time of detecting the outermost circumferential surface, the initial position of the inner circumferential surface at the current track position, that is, the track position of the inner circumferential surface is again. Move the track to the position (S170). Thereafter, while performing the constant speed regeneration (S180) operation of driving the spindle motor at a rotation speed of about 3000 rpm, the position of the current track is detected (ADd) (S190), and compared with the address (ADs) of the stored defect generation area ( S200).

If the result of the comparison does not match, it is determined that the disk is in the steady state region, and the constant speed playback operation is continued. To reduce the rotational speed of the spindle motor to about 2000rpm (S210). The operation is similarly terminated when the outermost peripheral surface of the disc is detected (S220).

FIG. 5 schematically shows partial reproducing operations S100 to S150 for detecting the defect generation region, and FIG. 6 shows information of a defect region detected by the detecting operation, and corresponds to a center corresponding to the defect region. When the track (track position) and the corresponding absolute time information (hour, minute, second) are simultaneously stored and a section corresponding to the center track and the absolute time information is detected during the constant speed playback (S180), the low speed playback (S210) This control is made (S210).

As described above, when the disc is inserted, the physical signal for the entire area of the disc is partially reproduced to detect and store the defect generation area in advance, and then, during constant speed playback, a separate repeat play is performed in the defect generation area. By performing the low speed regeneration operation without operation, a faster and more stable regeneration operation is achieved.

The playback speed control method according to the defect of the optical disc according to the present invention as described above, the time required to switch the operation to the low-speed playback after a number of repeated playback operations for identifying the disc defect area and precise playback As a result, it is a useful invention that a more stable reproducing operation can be performed, as well as a forward / reverse tracking operation required for the repetitive reproducing operation can be performed.

1 is a configuration diagram of a general optical disc player,

2 is a partial configuration diagram of an optical disc player to which a reproduction speed control method according to a defect of an optical disc according to the present invention is applied;

3 is a flowchart illustrating a playback speed control method according to a defect of a conventional optical disc,

4A and 4B are flowcharts illustrating a playback speed control method according to a defect of an optical disc according to an embodiment of the present invention.

5 schematically illustrates a partial reproducing operation applied to a reproducing speed control method according to a defect of an optical disc according to an embodiment of the present invention.

FIG. 6 shows defect area information detected by a playback speed control method according to a defect of an optical disc according to an embodiment of the present invention.

※ Explanation of code for main part of drawing

3: Spindle Motor 7: Servo

8: Driver 9: Digital Signal Processing Unit (DSP)

12: Memory 21: Micom

29: normal synchronous signal detector

Claims (2)

Detecting a normal synchronous signal in the playback track while partially reproducing the disc at random intervals when the disc is inserted; Storing an area corresponding to a playback track position as a defective area according to the normal synchronization detection; After step 2, step 3 of comparing the current playback track position with the stored defective area while performing constant speed playback; And And a fourth step of varying from constant speed playback to slow playback if the current playback track position corresponds to a defective area. According to claim 1, The partial playback of step 1 is performed by repeating playback for a predetermined track period while track jumping by 50 to 150 tracks corresponding to the size of the disk defect.