JPH11283343A - Optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the data transfer speed to be kept to a constant value, when a dynamic image is reproduced from a disk and the data are forwarded by correcting the error. SOLUTION: Binarization data of one ECC(error correction code) block reproduced from the disk are demodulated by a demodulating part 61 and stored in the region A of a memory 63 through a selector 62, then the error is corrected by an error correction circuit 64. In the case the error correction for the region A is not being completed when the next ECC block is all stored in the region B of the memory 63, the data in the region A, for which the error is corrected up to the midst, are transferred to the external device through a DMA transfer circuit 65.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk apparatus, and more particularly to an optical disk apparatus that reproduces a moving image while correcting data errors.

[0002]

2. Description of the Related Art An optical disk apparatus for recording and reproducing information is
Recording information on an optical disk by laser light output from a semiconductor laser oscillator in an optical head, converting the information recorded on the optical disk into an electric signal using a detector in the optical head, and reproducing the information. Can be.

When such data is reproduced by an optical disk device, the reproduced data is written to the memory at a constant transfer speed, and when one ECC (error correction code) block of data is written to the memory, an error correction operation is started. I do. The error correction operation is performed to correct data errors caused by defects, dust, dust, scratches, and the like on the optical disk medium. The data error is corrected by the optical disk device performing an error correction operation, and the device transfers the corrected data to the host computer.

FIG. 8 shows one ECC block showing the data format of a DVD. This ECC block is 16
Each sector has 32 Kbytes of data. Each sector records about 2 Kbytes of data, and sector IDs ID1 to ID16 are assigned to each sector as address data. Each sector has 172 bytes, 12 rows of data, and a horizontal ECC 1 of 10 bytes for each row, and a vertical ECC 2 for vertical data. The ECCs 1 and 2 are error correction codes added to the data as redundant words in order to prevent the data from being unable to be reproduced due to a defect in the optical disk. Stronger error correction can be performed by repeating vertical and horizontal error correction than when error correction is performed from a single direction using the error correction code configured as described above.

[0005]

SUMMARY OF THE INVENTION
If the horizontal error correction is repeated, the error correction time becomes longer.If the error correction time is remarkable, there is no more area to write the playback data to the memory. is there.

[0006] When reproducing a moving image in an optical disk device, it is necessary to maintain a data transfer speed at a certain value or more so that image display is not interrupted rather than data reliability. However, when there are many errors in the data, the correction operation does not end within a predetermined time, an overrun occurs, and the data transfer speed cannot be maintained. Therefore, the conventional method has a problem that it is not suitable for reproducing a moving image.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an optical disk apparatus capable of maintaining a data transfer speed at a certain value or more when reproducing moving image data from an optical disk and performing error correction on the reproduced data and transmitting the data. And

[0008]

According to the present invention, in order to solve the problem that the error correction time increases during reproduction of a moving image and the data transfer speed cannot be kept constant,
If the error correction operation is not completed within the data reproduction time of the ECC block, the error correction operation is interrupted and the data of the block is transferred to the host computer, thereby making the data transfer speed constant. Even when the error of the data cannot be removed as a result of the error correction, the data transfer of the error block is performed to maintain the data transfer speed.
Since the operation is interrupted in the middle of the error correction operation, the reliability of data is reduced, but the data transfer speed can be kept constant.

That is, an optical disk apparatus according to the present invention comprises a reproducing means for reproducing moving image data recorded on an optical disk, and a first memory for storing a predetermined amount of first reproduced data reproduced by the reproducing means in a first memory. 1 storage means, a correction means for correcting an error in the reproduction data stored in the memory, and a second storage for storing a predetermined amount of the second reproduction data reproduced by the reproduction means in the second memory. Means, transfer means for transferring the reproduction data corrected by the correction means to an external device, and storing in the first memory within a predetermined time required for the reproduction means to reproduce the predetermined amount of data. A first control unit for controlling the correction unit to interrupt the correction operation when the error correction for the first reproduced data is not completed; It said transfer means a predetermined amount of data; and a second control means for controlling to transfer to the external device.

The first control means determines the elapse of the predetermined time by referring to a storage address when the second storage means stores the second reproduced data in the second memory.

The information processing apparatus of the present invention further comprises a reproducing means for reproducing a predetermined amount of data and storing the reproduced data in a memory; a correcting means for correcting an error in the reproduced data stored in the memory; Transfer means for transferring the reproduction data corrected by the correction means to an external device; and error correction for the predetermined amount of data is not completed within a predetermined time required for the reproduction means to reproduce the predetermined amount of data. First control means for controlling the correction means to interrupt the correction operation, and second control means for controlling the transfer means to transfer the predetermined amount of data corrected halfway by the correction means to the external device. Means.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings, FIG. 1 is a block diagram showing a configuration of an optical disk device according to the present invention, FIG. 2 is a block diagram showing a configuration of an optical disk controller of the present invention, and FIG. 3 is a block diagram showing a memory arrangement of the optical disk controller of the present invention. 4 and 5 are block diagrams showing the operation of the optical disk controller.
FIG. 7 is a block diagram showing the operation of the optical disk controller of the present invention, FIG. 7 is a flowchart showing the operation of the optical disk controller of the present invention, FIG. 8 is a diagram for explaining the configuration of the ECC block, and FIG. FIG.

The optical disk device according to the present invention shown in FIG. 1 records, reproduces and erases information on an optical disk 1 using convergent light. Grooves (recording tracks) are formed in a spiral shape on the surface of the disk 1,
The disk 1 is rotated at a predetermined speed by a motor 2. The motor 2 is controlled by a motor control circuit 18.

Recording and reproduction of information on and from the disk 1 are performed by an optical head 3 provided below the disk 1. The optical head 3 is fixed to a drive coil 13 constituting a drive unit of a linear motor 31. The drive coil 13 is connected to a linear motor control circuit 17
It is connected to the.

The fixed portion of the linear motor 31 is provided with a permanent magnet (not shown).
When the optical head 3 is excited by the linear motor control circuit 17, the optical head 3 is moved in the radial direction of the disk 1.

A linear motor position detector 26 is connected to the linear motor control circuit 17. The linear motor position detector 26 outputs a position signal in relation to an optical scale 25 provided on the optical head 3.

The optical head 3 holds an objective lens 6 by a wire or a leaf spring (not shown). The objective lens 6 is moved by the drive coil 5 in the focusing direction (the direction of the optical axis of the lens). 4 enables movement in a tracking direction (a direction orthogonal to the optical axis of the lens).

A laser beam generated by a laser diode 9 serving as a semiconductor laser oscillator driven by a laser control circuit 51 passes through a collimator lens 11a, a half prism 11b, and an objective lens 6 to the disk 1.
The light irradiated upward and reflected from the disk 1 is guided to the photodetector 8 via the objective lens 6, the half prism 11b, the condenser lens 10a, and the cylindrical lens 10b.

In the vicinity of the laser diode 9, a monitoring photodiode PD is provided as a light emission amount detecting device for detecting the light emission amount of the laser diode 9. The monitor current as a detection signal from the photodiode PD is supplied to the laser control circuit 51. The photodetector 8 includes four photodiodes 8a to 8d.

The photodiodes 8a to 8 of the optical head 3
The cathode side of d is a common preamplifier 52 for video signals.
Are connected to the focus / tracking processing circuit 40, respectively.

As a result, a current flows from the cathode to the anode through the photodiodes 8a to 8d in accordance with the reflected light from the disk 1, and the video signal is processed using the sum current extracted from the cathode side. Focusing is performed using each current taken out from the anode side (keeping the distance between the disk 1 and the objective lens 6 constant)
/ Tracking (according to a guide groove recorded in the disk 1 in advance) is performed.

The focus / tracking processing circuit 40 includes the focusing control circuit 15 and the tracking control circuit 1
6, a linear motor control circuit 17, an adder 30a, differential amplifiers OPI and OP2, and amplifiers 12a to 12d.

That is, the output of the photodiode 8a of the photodetector 8 is supplied to one end of the adders 30a and 30c via the amplifier 12a, and the output signal of the photodiode 8b is supplied to the adders 30b and 30d via the amplifier 12b. An output signal supplied to one end and output from the photodiode 8c is supplied to an amplifier 12c.
Is supplied to the other ends of the adders 30b and 30c, and the output signal of the photodiode 8d is supplied to the other ends of the adders 30a and 30d via the amplifier 12d.

The output signal of the adder 30a is a differential amplifier OP
1 and the output signal of the adder 30b is supplied to the non-inverting input terminal of the differential amplifier OP1. As a result, the differential amplifier OP1 has the adders 30a, 3
A track difference signal corresponding to the difference voltage of 0b is supplied to the tracking control circuit 16. Tracking control circuit 16
Generates a track drive signal according to the track difference signal supplied from the differential amplifier OP1.

The track drive signal output from the tracking control circuit 16 is supplied to the drive coil 4 in the tracking direction. The track difference signal used in the tracking control circuit 16 is also supplied to the linear motor control circuit 17.

The output signal of the adder 30c is supplied to the inverting input terminal of the differential amplifier 0P2, and the non-inverting input terminal of the differential amplifier 0P2 is supplied with the output signal of the adder 30d. As a result, the differential amplifier 0P2 includes the adder 30c,
A focus difference signal related to the focus point is supplied to the focusing control circuit 15 according to the difference of 30d. The focusing control circuit 15 generates a focus drive signal according to the focus difference signal supplied from the differential amplifier OP2.

The focus drive signal output from the focusing control circuit 15 is
And the laser beam is controlled so that it is always just focused on the disk 1.

The photodiode 8a of the photodetector 8 in the state where focusing and tracking have been performed as described above.
The sum current of the outputs 〜8d reflects the information of the pits formed on the track. This sum current is converted into a voltage value by a video signal preamplifier 52 and supplied to the video signal processing circuit 19 as a video signal. The video signal processing circuit 19 binarizes the input video signal and outputs image data,
Generate address data (track number, sector number, etc.).

A recording signal generation circuit as a modulation circuit for modulating recording data supplied from a host device (for example, a personal computer) as an external device via an interface circuit 32 into a recording pulse is provided before the laser control circuit 51. 34 are provided.

Each of the disk devices is provided with a focusing control circuit 15, a tracking control circuit 16, and a D / A converter 22 used for transmitting and receiving information between the linear motor control circuit 17 and the CPU 23. ing.

The laser control circuit 51, focusing control circuit 15, tracking control circuit 16, linear motor control circuit 17, motor control circuit 18, signal processing circuit 19,
The recording signal generation circuit 34 and the like
It is connected to the PU 23 and the optical disk controller 60. The CPU 23 comprehensively controls the optical disk device together with the optical disk controller 60.
Reference numeral 23 performs a predetermined operation according to a program stored in the memory 24.

Next, an embodiment of the optical disk controller 60 according to the present invention will be described in detail. According to the present invention, in order to solve the problem that the error correction time increases during reproduction of a moving image and the data transfer speed cannot be kept constant, the data reproduction time of one ECC block (approximately 25
If the error correction operation is not completed within mS), the error correction operation is interrupted, and the data of the block is transferred to the host computer, thereby making the data transfer speed constant. When the error in the data cannot be removed as a result of the error correction, the data transfer of the error block is performed to maintain the data transfer speed. Since the operation is interrupted during the error correction operation, data reliability is low, but the data transfer speed can be kept constant.

FIG. 2 shows an optical disk controller 6 according to the present invention.
FIG. 3 is a block diagram showing a configuration of a 0. First, the 8/16 demodulation unit 61 of the optical disk controller 60 performs 8/16 demodulation on the binary data reproduced from the optical disk medium.

FIG. 9 is a conversion table for explaining 8/16 demodulation. The 8-bit data to be recorded on the optical disc 1 is recorded after being converted into a 16-bit code in order to guarantee the recording accuracy. That is, a certain 8-bit data (data before conversion in the figure) is a 16-bit code (figure in the figure) of four states from state 1 to state 4 corresponding to this data. Conversion code)
Is selectively modulated into any one of the codes. The selection of the code at the time of this modulation is performed when the selected code is linked to a code recorded before this code, and the DSV (digital sum v
alue) is as close to 0 as possible. That is, in the 8/16 modulation, the state of the next code following a certain code is determined in advance. FIG.
"NS" indicates the state of the next data.

After the demodulation section 61 demodulates the 16-bit code into 8-bit data, the demodulated data in units of 8 bits is written on the memory 63. 1 on memory 63
When data of the ECC block is written, the error correction circuit 64 performs error correction on the block. At this time, the demodulated data is continuously written by the demodulation unit 61 on the next memory area. The block for which error correction has been completed is DMA-transferred to the host computer via the I / F 32. At this time, a conventional case in which data transfer is interrupted due to an increase in error correction time will be described.

FIG. 3 is a block diagram showing a memory arrangement in the optical disk controller, and FIG. 4 is a timing chart showing a state of data reproduction, error correction and DMA transfer of the ECC block. For example, if the memory size is 3E
As a CC block, demodulated data is A, B,
C shall be written in the order of C. At the time of data reproduction as at time t0 in FIG. 4A, first, demodulated data is written to the A area. When data for one ECC block is written in the area A, the error correction circuit 6 is turned on at time t1 in FIG.
4 starts error correction for the data in the A area. The demodulated data is subsequently written in the order of the B and C areas. After the area C, writing is performed in the area A. In this case, in FIG.
As shown in FIG. 5B, it takes time to correct the error of the A area data, and if the data transfer to the I / F 32 is not completed at time t3 in FIG. 5C, there is no free area in the memory. Therefore, data reproduction is interrupted. In such a case, data cannot be reproduced until the data in the area A is DMA-transferred and an empty area is generated.

The operation of the optical disk controller 60 according to the present invention for preventing the above-mentioned interruption of data reproduction from occurring will now be described. FIG. 6 is a timing chart showing the operation of the constant transfer rate circuit 66 of the optical disk controller 60 of the present invention, and FIG. 7 is a flowchart thereof.

As shown in FIG. 6 (a), at time t0, writing of reproduced data to the area A is started (step ST1), and error correction is started at the end of writing as at time t1 (step ST2). At time t1, writing to the area B is started (step ST3). At this time, the constant transfer rate circuit 66 performs time division between the operation in which the demodulated data from the 8/16 demodulation unit 61 of the selector 62 is written into the B area and the operation in which the data in the A area is error corrected by the error correction circuit 64. The selector 62 is controlled so as to be performed in the format. That is, while the binary data for the area B is transferred from the disk 1 to the 8/16 demodulation unit 61 in 16-byte units, the data in the area A is error-corrected. Therefore,
Error correction of area A in step ST2 and step ST3
Are performed substantially simultaneously.

The constant transfer speed circuit 66 refers to the memory write address and determines whether the writing to the area B has been completed (step ST4). When the error correction for the area A is not completed at the time when the writing of the reproduction data to the area B is completed as at time t2 in FIG.
The constant transfer rate circuit 66 resets the correction circuit 64 and stops error correction for the A area (step ST).
6), the data in the area A is DMA-transferred as shown in FIG. 6C (step ST7). The error correction operation is started for the area B (step ST8), and data is written to the area C (step ST9). At this time, as described above, the transfer rate constant circuit 66 performs the DMA transfer of the area A in step ST7, the error correction of the area B in step ST8, and the writing of the area C in step ST9 substantially simultaneously in a time-division manner. The selector 62 is controlled so as to be performed.

In the same manner, data writing, error correction and DMA transfer in the A area, B area and C area are performed. By doing so, the error correction time is limited to one ECC block reproduction time, and interruption of data reproduction due to an increase in the correction time can be prevented.

[0041]

When the error correction time is prolonged due to a large amount of error data in the reproduction data, the correction operation is terminated before the data transfer is interrupted due to the overrun, and the data transfer is performed. Can be kept constant. For this reason, there is no break in the moving image when reproducing the moving image.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an optical disk device to which the present invention is applied.

FIG. 2 is a block diagram showing a configuration of an optical disk controller of the present invention.

FIG. 3 is a block diagram showing a memory arrangement of the optical disk controller of the present invention.

FIG. 4 is a block diagram showing the operation of the optical disk controller.

FIG. 5 is a block diagram showing the operation of the optical disk controller.

FIG. 6 is a block diagram showing the operation of the optical disk controller of the present invention.

FIG. 7 is a flowchart showing the operation of the optical disk controller of the present invention.

FIG. 8 is a diagram for explaining a configuration of an ECC block.

FIG. 9 is a diagram for explaining 8/16 demodulation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Optical disk 3 ... Optical head 6 ... Objective lens 9 ... Laser diode 8a-8d ... Photodiode

Claims (7)

[Claims] A reproducing means for reproducing a predetermined amount of data and storing the reproduced data in a memory; a correcting means for correcting an error in the reproduced data stored in the memory; and a reproducing data corrected by the correcting means. Transfer means for transferring the predetermined amount of data to an external device, if the error correction for the predetermined amount of data is not completed within a predetermined time required for the reproduction means to reproduce the predetermined amount of data, A first control unit for controlling to interrupt the transfer; and a second control unit for controlling the transfer unit to transfer the predetermined amount of data partially corrected by the correction unit to the external device. Information processing device. 2. The information processing apparatus according to claim 1, wherein said predetermined amount of data is data of one ECC block, and said memory has a data storage capacity of at least three ECC blocks. 3. The information processing apparatus according to claim 1, wherein said reproduction data is moving image reproduction data. 4. A reproducing means for reproducing data recorded on an optical disk; a first storing means for storing a predetermined amount of first reproduced data reproduced by the reproducing means in a first memory; Correction means for correcting an error in the reproduction data stored in the storage means, a second storage means for storing a predetermined amount of the second reproduction data reproduced by the reproduction means in a second memory, Transfer means for transferring the corrected reproduction data to an external device; and the first reproduction stored in the first memory within a predetermined time required for the reproduction means to reproduce the predetermined amount of data. If the error correction for the data does not end,
First control means for controlling the correction means to interrupt the correction operation; and second control means for controlling the transfer means to transfer the predetermined amount of data partially corrected by the correction means to the external device. An optical disk device comprising a control unit. 5. The optical disk device according to claim 4, wherein the predetermined amount of data is data for one ECC block. 6. The optical disk device according to claim 4, wherein said reproduction data is moving image reproduction data. 7. The first control means judges the elapse of the predetermined time by referring to a storage address when the second storage means stores the second reproduced data in the second memory. The optical disk device according to claim 4, wherein