JP3153680B2 - Recording and playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for compressing audio data generated from a digital audio signal of continuous information such as audio information, temporarily storing the compressed data in a buffer memory, and transferring the data at a higher transfer rate than the data transfer rate at the time of storage. The present invention relates to a recording / reproducing apparatus for intermittently reading audio data from a buffer memory and performing high-density recording on a recording medium, and more particularly to a recording / reproducing apparatus for dubbing audio information from a compact disc reproducing system to a mini disc recording system. .

[0002]

2. Description of the Related Art In the last ten years, the recording / reproducing system for audio signals has been rapidly shifting from an analog system to a digital system. As recording media for consumer use, compact discs (hereinafter, referred to as CDs), which are optical discs exclusively for reproducing digital audio signals, digital compact cassettes, which are magnetic tapes for recording and reproducing, recording /
A mini disk (hereinafter, referred to as MD), which is a magneto-optical disk capable of reproducing / erasing, has been developed. MD above
Is smaller than a CD and has a diameter of about １ ／ of a CD.
It has become. Also, the digital audio signal recorded on the MD has an ATRAC (Adaptive Transform Acoustic Code) in order to secure the same information recording amount as the CD.
ng), the data is compressed to about 1/5 by the audio efficient coding method.

[0003] In a digital drive device that handles the above-described recording medium, two types of recording media are mounted.
There is a need for a dubbing function that can transfer audio information from one recording medium to another recording medium.
For example, Japanese Patent Application Laid-Open Nos.
JP-A-258834 discloses a recording / reproducing apparatus capable of dubbing a compressed digital audio signal recorded on an MD at a high speed.

Japanese Patent Application Laid-Open No. 3-119559 discloses a processing method when a reproduction error occurs on the CD side when dubbing audio information from a CD to an analog compact cassette.

[0005]

However, Japanese Patent Application Laid-Open Nos. Hei 4-332960 and Hei 4-258834 describe the above.
This publication does not disclose a retry method for eliminating an error so that dubbed audio information is not interrupted when a reproduction error or a recording error occurs.

[0006] Also, the above-mentioned Japanese Patent Application Laid-Open No. 3-119559 discloses a process in which dubbing is resumed after returning to an error occurrence position on each recording medium. Since an audio signal is recorded, it is difficult to perform strict continuous recording at an error occurrence position.

Further, as in the case of dubbing audio information from a CD to an MD, a digital audio signal may be transferred between recording media having different recording formats. In this case, it is a future task to establish a retry technique for re-dubbing from an error occurrence position so that audio information is not interrupted or duplicated when a recording error or a reproduction error occurs.

[0008]

In order to solve the above-mentioned problems, a recording / reproducing apparatus according to the present invention uses a digital data from a first recording medium (for example, CD) in which digital data is sequentially recorded for each access unit. A recording / reproducing apparatus including a reproducing system for reading data and a recording system for compressing the digital data and recording the digital data on a second recording medium (for example, MD), characterized by including at least the following units. I have. That is, (1) storage means (for example, a shock-proof memory) for temporarily storing the compressed data compressed by the recording system for each compression unit, and (2) the compressed data compressed by the recording system Storage means
While storing multiple compression units as minimum recording units.
Reading the compressed data from the storage means and
Recording means for recording on a recording medium (for example, a system control microcomputer, a memory controller, an encoder / decoder signal processing circuit, a head driving circuit, a recording head, and an optical pickup); (3) a reproduction error on the first recording medium and Stop instruction means (for example, a system control microcomputer) for detecting at least one of recording errors in the second recording medium and temporarily suspending operations of a recording system and a reproduction system based on the detection; Reproduction control means (for example, a reproduction control unit for resuming reproduction from a plurality of access units before the access unit in which the error occurred, by detecting which access unit on the recording medium caused the error during reproduction) System control microcomputer), (5) Playback resumed The compressed data corresponding to a unit of access read to determine from said storage means, and new compressed data and verify obtained after resumption of the reproduction, detecting each head position of the unit of compression in the new compressed data verification Means (for example, a system control microcomputer); (6) storage control means (for example, memory) for rewriting new compressed data to the storage means from the beginning of the unit of compression in which an error has occurred, based on the detection result of the verification means. (7) The compressed data from the head of the minimum recording unit in which an error has occurred is read out from the storage means, and the compressed data is stored in the recording system.
Recording control means for restarting recording on the recording medium (for example, a system control microcomputer).

[0009]

According to the above arrangement, digital data read from the first recording medium for each access unit is compressed by the recording system and stored in the storage means for each compression unit. However, the data length of the access unit and the data length of the compression unit do not need to match. Since a plurality of compression units are recorded as the minimum recording unit on the second recording medium, when at least compressed data of the minimum recording unit is stored in the storage unit, the compressed data is read from the head of the minimum recording unit. It is recorded on the second recording medium.

Therefore, if an error occurs during recording of a certain minimum recording unit, at least the compressed data of the minimum recording unit during the recording is stored in the storage means for each compression unit. Therefore, if the reproduction of the first recording medium is resumed after the occurrence of the error and the newly compressed data can be double-written on the same compressed data stored in the storage means, Dubbing from one recording medium to the second recording medium via the storage means can be continued regardless of errors.

[0011] For this purpose, it is necessary to perform verification for confirming that new compressed data after resuming reproduction matches compressed data stored in the storage means. As a procedure of the verification, it is detected which unit of the access has occurred during reproduction on the first recording medium. The reproduction is restarted from the access unit before the access unit where the error has occurred by a plurality of units. The compressed data corresponding to the unit of access for which the reproduction has been resumed is determined and read from the storage means. The compressed data read from the storage unit is verified with new compressed data obtained after resuming reproduction. The head position of each unit of compression in the new compressed data is detected, and the corresponding storage position of the storage means is confirmed. New compressed data is double-written in the storage unit from the beginning of the compression unit in which an error has occurred. After all the compressed data of the minimum recording unit in which the error has occurred is completely written in the storage means, the compressed data from the beginning of the minimum recording unit is read out from the storage means and recorded on the second recording medium. Is resumed, dubbing can be continued irrespective of interruption due to an error.

[0012]

As described above, according to the present invention, even if the recording formats of the first recording medium and the second recording medium are different, the digital data of the first recording medium is dubbed to the second recording medium. An error that has occurred can be eliminated with simple control contents. In addition, since the operations of the reproducing system and the recording system are temporarily stopped when an error occurs, the present invention can be applied to a case where digital data is transferred from the reproducing system to the recording system at a higher speed than the normal reproducing speed.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. However, in the present embodiment, as an example of the recording / reproducing apparatus according to the present invention,
A recording / reproducing system including an MD recording / reproducing system for recording / reproducing audio information to / from an MD and a CD reproducing system for reproducing audio information from a CD, and configured to be able to dub audio information from a CD to the MD. The device will be described.

As shown in FIG. 5, the MD recording / reproducing system mounts a disk 31 as an MD (a second recording medium according to the present invention), an optical pickup 32, and an RF.
An amplifier 33, an encoder / decoder signal processing circuit 34,
Shock proof memory controller (hereinafter, referred to as memory controller) 5, shock proof memory (buffer memory) 6, audio expansion / compression circuit 7, D / A / A
/ D converter 8, system control microcomputer (hereinafter referred to as system control microcomputer) 9, servo circuit 10, driver circuit 11, spindle motor 12, feed motor 13, power supply ON / OFF circuit 14, head drive circuit 15, recording head 16, audio output terminal 17, audio input terminal 18, changeover switch 19,
And a key determination circuit 42.

On the other hand, the CD reproduction system has a CD 41 as a CD (first recording medium) and a CD reproduction device 20. The CD playback device 20 performs normal playback of the disc 41 while being controlled by the system control microcomputer 9, and reads audio information from the disc 41 at a higher speed than during normal playback when dubbing audio information of the disc 41 to the disc 31. Is controlled as follows.

At the time of reproduction of the disc 31,
Is the spindle motor 1 driven by the driver circuit 11
2 is driven to rotate. An optical pickup 32 for reading audio data recorded on a disc 31
The disk 31 is fed in the radial direction of the disk 31 by a feed motor 13 driven by a driver circuit 11. Further, the objective lens of the optical pickup 32 is driven in a focusing direction and a tracking direction by an actuator (not shown) driven by the driver circuit 11.

The audio data read by the optical pickup 32 is amplified by an RF amplifier 33 and sent to an encoder / decoder signal processing circuit 34. Also,
The RF amplifier 33 generates a servo control signal such as a focus error signal and a tracking error signal from the read audio data, and outputs this to the servo circuit 10.

The servo circuit 10 uses the servo control signal from the RF amplifier 33 and a control signal from the system control microcomputer 9 to control the optical pickup 3.
The driver circuit 11 is controlled so as to apply servo to the focusing and tracking in step 2 and the rotation speed of the disk 31. Further, the driver circuit 11
Drives the optical pickup 32, the spindle motor 12, and the feed motor 13 according to a control signal from the servo circuit 10.

The encoder / decoder signal processing circuit 3
4 demodulates the audio data amplified by the RF amplifier 33, performs signal processing such as error correction, and sends the signal processing to the memory controller 5. The memory controller 5 writes the audio data sent from the encoder / decoder signal processing circuit 34 into a shockproof memory 6 as a storage unit described in the claims. The shock proof memory 6 includes TO information as additional information related to the audio data in addition to the area for storing the audio data.
An area for storing C information is provided.
Is inserted from the disc 31 immediately after the TOC
The information is read and stored in a predetermined area of the shock proof memory 6 along the same path as the audio data. Further, the memory controller 5 reads necessary TOC information from the shock proof memory 6 and sends it to the system control microcomputer 9 in response to a request from the system control microcomputer 9.

The system control microcomputer 9 comprises the recording means, the stop command means, the retry control means and the recording system control means described in the claims, controls the system based on the TOC information, and stores necessary data on a disk. Read from 31. The memory controller 5 sequentially reads out the audio data temporarily stored in the shock proof memory 6 and sends it to the audio expansion / compression circuit 7. The audio decompression / compression circuit 7 decompresses the transmitted audio data in the audio decompression circuit according to a predetermined format, and sends it to the D / A / A / D converter 8. The D / A / A / D converter 8 converts the transmitted digital signal into an analog signal in the D / A converter to generate an audio signal. This audio signal is output from the output terminal 17.

On the other hand, when recording audio information on the disk 31, there are a case where the audio information is inputted from an analog source and a case where the audio information is inputted from the CD reproducing device 20 as described above. This input system switching
This is performed by a changeover switch 19 controlled by the system control microcomputer 9.

When audio information is input from an analog source, an analog audio signal is input to the A / D converter of the D / A / A / D converter 8 via the audio input terminal 18 and is converted into audio data. You.
However, depending on the speed at which audio data is transferred from the A / D converter to the audio expansion / compression circuit 7, the CD playback device 2
The speed at which the digital audio signal is transferred from 0 to the audio expansion / compression circuit 7 is higher. This is because, as described above, when dubbing the audio information of the disk 41 to the disk 31, the reading speed of the disk 41 becomes higher than that in the normal reproduction.

The audio expansion / compression circuit 7 uses the audio compression circuit to generate an ATRAC (Adaptive Transform Acoustic).
Coding), the audio data input through the changeover switch 19 is compressed to about 1/5 by the MD information compression technique and sent to the memory controller 5.
The memory controller 5 writes the input compressed audio data into the shockproof memory 6 once,
The compressed audio data is read from the shock proof memory 6 and sent to the encoder / decoder signal processing circuit 34. Here, modulation, addition of an error correction code, and the like are performed.

The system control microcomputer 9 controls the memory controller 5 to control the shockproof memory 6
A recordable area on the disk 31 is recognized based on the TOC information stored in the storage area, and the servo circuit 10 is controlled to search the recordable area. When the search for the recordable area is completed, the head drive circuit 15 drives the recording head 16 under the control of the system control microcomputer 9 based on the signal output from the encoder / decoder signal processing circuit 34. Simultaneously, the laser circuit of the optical pickup 32 is driven by the driver circuit 11, so that a portion of the disk 31 to which a magnetic field is applied is irradiated with a stronger laser than during reproduction, so that modulated data is recorded on the disk 31. The optical pickup 32, the encoder / decoder signal processing circuit 34, the memory controller 5, the head drive circuit 1
The recording head 5 and the recording head 16 constitute recording means described in the claims.

When the recording on the disk 31 is completed, the system control microcomputer 9
To rewrite the TOC information stored in the shock-proof memory 6 and use the updated TOC information as the latest TOC information to manage the audio information recorded on the disk 31. For example, a TOC area (called a U-TOC area) provided on the inner peripheral side of the disk 31 is rewritten with the latest TOC information.

In the above configuration, when dubbing audio information from the CD to the MD, the dubbing speed is higher than the normal speed, not only when a reproduction error occurs on the CD side, but also when a recording error occurs on the MD side. Indeed, there is a high possibility that the shock proof memory 6 cannot absorb the rewriting time. Therefore, if compressed audio data is to be continuously recorded so that recording is not interrupted at an error occurrence location, a retry process for accessing the error occurrence location on the CD and the MD is required.

The problem here is that the recording format differs between the CD and the MD. Each parameter is summarized and shown below.

[CD] 1 frame = 6 sampling data 1 subcode frame = 98 frame = 588 sampling data = 1/75 second Access unit = each subcode frame [MD] 1 sound group = 512 sampling data (compression unit 1 sector = 5.5 sound group = 2816 sampling data 1 cluster = 32 sectors = 176 sound group = 90112 sampling data Access unit = per sector Minimum recording unit = cluster unit As described above, the data length of the unit of access in the CD is as described above. Is different from the data length of the unit of compression in the MD, or the data length of the unit of access and the minimum recording unit. Therefore, at the time of the retry process, the timing of resuming the reproduction of the CD and the timing of resuming the recording of the MD are adjusted. Control It becomes essential. Therefore, in order to facilitate this control, FIG.
As shown in (a) to (c), the system control microcomputer 9 counts each time audio data (512 sampling data) for one sound group is read out from the CD reproducing device 20, and the audio data is counted for each sound group. Good to manage.

In the dubbing operation from the CD reproducing system to the MD recording / reproducing system, as shown in FIGS. 2A and 2B, the reading of audio data from the disk 41 (CD) starts, and the MD recording / reproducing system starts. The audio data transmitted to the audio decompression / compression circuit 7 is compressed to about 1/5 for each sound group, and is sequentially written to the shockproof memory 6 by the memory controller 5.

As shown in FIG. 2C, until the compressed audio data belonging to the cluster 1 which is the first recording unit to be recorded on the disk 31 (MD) is completely written into the shockproof memory 6, the disk 31 Then
The recording start position of cluster 1 has been searched.

Next, at the same time as the writing of the cluster 1 to the shock proof memory 6 is completed and the writing of the cluster 2 is started, the cluster 1 is read from the shock proof memory 6 at a higher rate than the writing rate, and 31 is recorded. As described above, since the reading speed from the shock proof memory 6 is faster than the writing speed, the reading of the compressed audio data from the shock proof memory 6 is performed intermittently. As a result, after the compressed audio data of the cluster 1 has been read from the shock proof memory 6, the shock proof memory 6
During the period until the writing of the cluster 2 is completed, the recording start position of the cluster 2 is searched on the disk 31. When the cluster 2 has been recorded on the disk 31, the reproduction of the disk 41 has been completed up to the middle of the cluster 3.

Next, as shown in FIGS. 2A and 2B, when compressed audio data up to the point A of the cluster 3 is recorded on the disk 31, for example, a shock is applied from the outside, so that the optical pickup 32 Track deviation, C
It is assumed that skipping occurs in the D playback device 20. That is, in this case, the minimum recording unit in which the error has occurred is the cluster 3. At this time, the system control microcomputer 9 detects a recording error or a reproduction error, temporarily stops the recording operation of the MD recording / reproducing system and the reproducing operation of the CD reproducing device 20, and starts a retry process.

In this case, the recording up to the cluster 2 is normally performed on the disk 31, and the compressed audio data of the cluster 3 is normally written in the shock proof memory 6. If playback is resumed after returning slightly from the playback position of the disk 41 at the time of occurrence of the error, the newly obtained compressed audio data overlaps with the compressed audio data already stored in the shockproof memory 6. Therefore, it is checked whether the compressed audio data stored in the shockproof memory 6 matches the newly obtained compressed audio data, and the shockproof memory 6
The error can be eliminated by writing over the same compressed audio data.

In this way, after the double writing of the cluster 3 in the shock proof memory 6 is completed, if the data is read from the beginning of the cluster 3 and recorded on the disk 31 again, and dubbing after the cluster 4 is continued as usual, an error occurs. , The compressed audio data can be continuously dubbed on the disk 31 without being affected by the above.

Hereinafter, the verification between the new compressed audio data after the reproduction is resumed and the compressed audio data stored in the shock proof memory 6 will be specifically described.

First, in consideration of the compression format of the compression LSI used in the audio decompression / compression circuit 7, the disk 41 has, for example, the sound group two points before the point A (FIG. The reproduction is resumed from the sound group 25) as shown in b). However,
Since the unit of access to the CD is one subcode frame, the disk 41 actually accesses the head of the two previous subcode frames. Disk 41
1A, a synchronization signal (subcode frame sync) reproduced from the beginning of each subcode frame is used as shown in FIG. In the present embodiment, the system control microcomputer 9 searches the subcode frame sync 21 and causes the CD playback device 20 to resume playback of the disc 41.

Subsequently, the system control microcomputer 9
Is based on the correspondence between the data in the sub-code frame starting from the sub-code frame sync 21 and the data in the sound group 25, and after the reproduction of the disk 41 is resumed, a new output from the audio decompression / compression circuit 7 is output. The compressed audio data corresponding to the compressed audio data is determined and read from the shock proof memory 6. And
By verifying the new compressed audio data with the stored compressed audio data, FIG.
As shown in FIG.
Find the beginning of After confirming the storage position of the shock-proof memory 6 in this way, as shown in FIG.
The memory controller 5 is instructed to restart writing to the shock proof memory 6 from the sound group 27 which is a unit of compression in which an error has occurred. Thus, the compressed audio data from the sound group 27 to the sound group 176 of the cluster 3 is double-written.

Until all the compressed audio data of the cluster 3 is completely written into the shock proof memory 6,
In the disk 31, the recording start position of the cluster 3 is searched. At the point when the cluster 3 has been written into the shockproof memory 6, the disk 31
Is restarted from the beginning of cluster 3. Thus,
The audio data on the disk 41 is continuously dubbed to the disk 31 without being affected by the occurrence of the error.

When the data transfer speed from the CD reproduction system to the MD recording / reproduction system is high, there is a possibility that the time required for rewriting in the shock proof memory 6 cannot be absorbed. When the operation of the MD recording / reproducing system is temporarily stopped and the rewriting to the shock proof memory 6 is completed, the recording to the MD is restarted, so that the error is surely resolved regardless of the data transfer speed.

[0041]

As described above, the recording / reproducing apparatus according to the present invention comprises a storage means for temporarily storing compressed data compressed by a recording system for each unit of compression,
While storing compressed data in the storage means, a plurality of compressed
The unit is the minimum recording unit, and the compressed data is
Recording means for reading the data and recording the data on the second recording medium; detecting at least one of a reproduction error on the first recording medium and a recording error on the second recording medium; Stop command means for temporarily stopping the operation of the first recording medium, detecting which access unit has caused an error during reproduction on the first recording medium, and a reproduction control means for resuming the reproduction to the reproduction system reads compressed data corresponding to the unit of access to resume playback to determine from said storage means, and new compressed data and verify obtained after resumption of the reproduction, Verifying means for detecting each head position of a unit of compression in the new compressed data; and error detection based on the detection result of the verifying means. From the beginning of the unit of compression and write correct storage control unit a new compressed data in the storing means without the compressed data from the beginning of the minimum recording unit of an error by reading from the storage means, above recording system second
Recording control means for restarting recording on the recording medium.

Therefore, even if an error occurs during the dubbing of audio data from the first recording medium to the second recording medium having a different recording format, the audio data is reproduced again from the compression unit immediately before the occurrence of the error and stored. Since the data is rewritten to the means, the audio data can be continuously dubbed on the second recording medium without being affected by the error. Further, the operation of the reproducing system and the recording system is temporarily stopped at the time of occurrence of the error, so that even if the data transfer speed from the reproducing system to the recording system is high, the error can be reliably eliminated.

[Brief description of the drawings]

FIG. 1 is a timing chart showing a retry process of a recording / reproducing apparatus according to the present invention.

FIG. 2 shows an operation of reading audio data from a CD, M
5 is a timing chart showing a relationship between an operation of compressing and storing audio data in a D recording / reproducing system and an operation of recording compressed audio data on an MD.

FIG. 3 is an explanatory diagram showing recorded contents of digital data in an MD after a retry process.

4A and 4B are explanatory diagrams showing that audio data reproduced from a CD is managed with the same data length as a compression unit in the MD, and FIG. 4C is a diagram showing the minimum recording unit of the MD. FIG. 4 is an explanatory diagram showing a data length.

FIG. 5 is a block diagram showing a configuration example of a recording / reproducing apparatus according to the present invention.

[Explanation of symbols]

2 Optical pickup (recording means) 4 Encoder / decoder signal processing circuit (recording means) 5 Shock proof memory controller (recording means and storage control means) 6 Shock proof memory (storage means) 9 System control microcomputer (recording means, stop command means) , Reproduction control means, verification means and recording control means) 15 head drive circuit (recording means) 16 recording head (recording means) 20 CD reproducing device (reproduction system) 31 disk (second recording medium) 41 disk (first recording medium) )

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ identification code FI G11B 20/10 G11B 20/10 F 301 301A (58) Investigated field (Int.Cl. ⁷ , DB name) G11B 20/18 G11B 7/00 G11B 19/02 G11B 20/10

Claims (1)

(57) [Claims] 1. A reproducing system for reading digital data from a first recording medium on which digital data is sequentially recorded for each access unit, and a reproducing system for compressing the digital data to a second system.
A recording / reproducing apparatus comprising: a recording system for recording on a recording medium; storage means for temporarily storing compressed data compressed by the recording system for each compression unit; and compressed data compressed by the recording system. In the storage means
While using multiple compression units as minimum recording units,
Reading the compressed data from the storage means and performing the second recording
Recording means for recording on a medium, detecting at least one of a reproduction error in the first recording medium and a recording error in the second recording medium, and suspending operations of a recording system and a reproduction system based on the detection. Stop command means for detecting which access unit has an error during reproduction on the first recording medium, and reproducing the reproduction from a plurality of access units prior to the access unit in which the error occurred to the reproduction system. Playback control means for restarting, and compressed data corresponding to the unit of access for which playback was restarted.
Read to determine from said storage means, and verifying means for new compressed data and verify obtained after resumption of the reproduction, detecting each head position of the unit of compression in the new compressed data, the detection result of the verification means A storage control unit that rewrites new compressed data to the storage unit from the head of the compression unit in which the error has occurred, and reads the compressed data from the head of the minimum recording unit in which the error has occurred from the storage unit, A recording / reproducing apparatus comprising: a recording system; and recording control means for restarting recording on the second recording medium.