JPH01178177A - Image recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent image information already recorded from being destroyed by moving a recording and reproducing head to the prescribed position of a disk shape recording medium when the tracking error of the head is generated on the middle way of recording or reproduction, and retrying a recording or reproducing operation. CONSTITUTION:A track jump detection circuit 48 always monitors a tracking error signal (T. error) from an optical R/W head 14, and judges that off-track is generated when the tracking error signal is magnified over a prescribed level, and impresses a detecting pulse C on a CPU 32 and an LD driving circuit 34. And when the off-track is generated at the time of recording, the LD driving circuit 34 lowers the level of a laser driving current immediately to the level at the time of reproduction. Also, the CPU 32 judges it as the failure of recording and reproduction, and retries the operation. In such a way, it is possible to prevent data at a part already recorded from being destroyed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image recording and reproducing apparatus that records image information on a recording medium and reproduces the image information previously recorded on the recording medium.

[Conventional technology]

In recent years, there has been increasing activity in converting still images into digital data and recording and storing it on large-capacity recording media, such as optical discs. )
It is proposed to use

In that case, image information will be recorded and reproduced according to the CD recording format.

In the recording format of audio data on a CD, as shown in Figure 2, one data frame consists of 588 bits, and each data frame has a 24-pin data frame synchronization pulse FS at the beginning. , followed by a 3-bit margin bit MB and a 14-bit data bit DB.The margin bit MB is 000.100,
The optimal one is selected from among 010,001. There are a total of 32 data bit DBs in one data frame, and 8-bit data is converted to 14 bits so that ``1'' is appropriately distributed.Data Bit DB
O is called subcode or user's bit,
Used for control signals and displays during playback. DBI~D
B12 and DB17 to DB28 are used for data, and DB1
3 to DB16 and DB29 to DB32 are used as C1 parity and C2 parity, respectively, based on Reed-Solomon's code.

A series of 98 data frames is called a data block, and various processes are performed using this one data block as a processing unit for recording and reproduction. The logical contents of one data block are shown in FIG. However, margin bit MB
and parity bits are excluded, each data bit DB
is shown after being decoded into 8 bits by 14-8 conversion.

In each block, the O-th data frame and the O-th data bit DBO of the first data frame are for block synchronization;
8 that make up the data bit DBO of the data frame
Bits P-W are called P channel to W channel, respectively, when viewed in the frame arrangement direction (vertical direction in the figure).

The P channel records a flag indicating whether it is a silent period or a sound period, and the Q channel stores information specific to the contents of the disc and information that changes from time to time on the disc, such as track numbers, indexes, and time codes. , absolute time, etc. are recorded. Time code is a recording data unit,
For example, it indicates the time from the beginning of one song, and the absolute time indicates the time from the recording start point of the disc.

Complex interleaving is applied to the data portion to prevent burst errors, but since this is not related to the present invention, the explanation will be omitted.

When recording still image data on an optical disc using this CD format, as shown in FIG. 4, a synchronization pattern "S" is added to the beginning of each image data.
After adding an end mark S to the end, this is converted into the above-mentioned CD format and recorded on an optical disc.

A slight gap as an unrecorded portion is generated between still images recorded on a DRAW or EDRAW type optical disc.

In an optical disk, data is generally recorded on one spiral track from the inner or outer circumference of the disk toward the outer or inner circumference.

Each recorded image is recorded simultaneously with a serial number associated with it for each recording block or other processing unit. During playback, the optical pickup is moved to the end of the recording area with the serial number 1 smaller than the target serial number or to the gap between the recording areas, the circuit is set to playback mode, and the synchronization pattern Sy at the beginning of the image data is first After that, the reproduced image data is transferred to an external memory.

When the end mark St is detected, the transfer to the external memory is stopped.

This serial number may be recorded by being included in, for example, the Q channel of the above-mentioned subcode P-W, in which case,
It is best to use a serial number associated with the Q channel track number (8 bits) and index number (8 bits).

[Problem to be solved by the invention]

Such a still image recording method has the following problems. That is, if tracking is lost during recording or reproduction of a still image, the image will not be recorded or reproduced normally. In addition, when additional recording is performed on an optical disc that has already recorded several images, there is a risk that the tracking will be lost and the data in the recorded areas will be destroyed, making it a big problem in system construction. This has become a problem.

Therefore, it is an object of the present invention to provide an image recording and reproducing apparatus that does not cause such inconveniences.

[Means to solve the problem]

The image recording and reproducing apparatus according to the present invention records a single image of information from either the innermost circumference or the outermost circumference of the disk-shaped recording medium toward the other side, thereby creating a spiral image on the disk-shaped recording medium. An image recording/playback device forming a recording trunk in the form of a disc-shaped recording medium, comprising: a recording/playback head for recording or reproducing image information on the disk-shaped recording medium; and a position of the recording/playback head with respect to the disk-shaped recording medium. The head moving means for moving the head and the tracking state of the recording/playback head are detected, and if the head is in a tracking error state, the tracking state is detected.
A tracking monitoring means outputs an error signal, and if a tracking error signal is output from the tracking monitoring means during recording or reproduction of image information, the head moving means is controlled to move the recording/playback head to the disk. It is characterized by comprising a recording/reproducing operation control means for moving the recording medium to a predetermined position on the shaped recording medium and retrying the recording or reproducing operation.

[Effect]

With the above configuration, if a tracking error occurs in the recording/playback head during recording or playback, the head is moved to a predetermined position on the disk-shaped recording medium and the recording or playback operation is retried. During a recording operation, it is possible to prevent image information already recorded on the disc-shaped recording medium from being destroyed, and during a reproducing operation, it is possible to prevent the generation of defective image information.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of the present invention. 1
0 is an optical disk which is a recording medium, 12 is an optical disk 10
14 is an optical reproducing/recording (R/W) head; 16 is a head feeding mechanism that sends the RAD 14 to the optical R/W in the radial direction of the optical disk 10; 18 is an optical R/W head;
/W A position detector 20 that detects the position of the head 14 in the disk radial direction converts the rotational speed of the spindle motor 12 into a frequency signal and outputs the frequency signal.
y Generator). Note that the description of the laser beam focus and tracking servo mechanism will be omitted.

22 is an analog-to-digital (A/D) converter that converts an input video signal into a digital signal, 24 is a memory that stores digital image data, and 26 is a converter that converts the digital image data stored in the memory 24 into an analog video signal. It is a digital to analog (D/A) converter. A
The pre-filter of the /D converter 22 and the post-filter of the D/A converter 26 are omitted from illustration. In the following description, it is assumed that recording and reproduction of the optical disc IO is performed on data stored in the memory 24.

First, the operation during recording will be explained. Sy, St addition circuit 2
8 adds the above-described synchronization pattern S and end mark SE to the beginning and end of the information read from the memory 24, respectively. The CD encoder 30 has Sy, St
ECC, a frame sync pattern, etc. are added to the output of the addition circuit 28, and the output is converted into a CD format. Note that at this time, subcode information A is supplied to the CD encoder 30 from the CPU 32. The main contents of subcode A are the serial number and block number of the image. The block number is expressed in three quantities: minutes, seconds, and blocks. This is related to the fact that one block is 1/75 second. The LD drive circuit 34 generates a laser drive current according to the output of the CD encoder 30, and
/W is applied to the head 14.

As a result, recording onto the optical disc IO is performed.

During recording, the recording CLV servo circuit 36
The spindle motor 12 is controlled by the rotational speed signal H from 0 and the position signal I from the position detector 18 of the optical R/W head 14 so that the optical disk 10 rotates at a constant linear velocity with respect to the disk 14. do. When recording, switch 3
8 is connected to the a contact side, and during playback is connected to the b contact side.

The operation during playback will be explained. The reproduction output of the optical R/W head 14 is amplified by a preamplifier 40 and demodulated by a CD decoder 42. The CD decoder 42 also performs error correction. The CD decoder 42 supplies the frame sync detection pulse E to the reproduction CLV servo circuit 44, and
The V servo circuit 44 controls the spindle motor 12 so that the frame sync detection period is constant. CD
The decoder 42 also separates the demodulated data into a data portion and a subcode, and supplies the subcode to the CPU 32. The CPU 32 reads the serial number and block number of the image using this subcode, and sends it to the optical R/W hand 1.
A control signal G is sent to the head feeding mechanism 16 to position the head 4 at the desired image recording position.

Further, the S,,S,detection circuit 46 detects S from the reproduced data string.
Immediately after the y pattern is detected, the data string following it is transferred to the memory 24, and when the SE pattern is detected, the data transfer to the memory 24 is stopped.

With the above configuration, it is possible to record and reproduce still images, but in this embodiment, a track jump detection circuit 48 is provided in order to solve the above problem when the track goes off track. The track jump detection circuit 48 is an optical R/W
The tracking error signal (T, er
ror) is constantly monitored, and when it becomes larger than the level at which a tracking error signal is generated, it is determined that the tracking is off, and the detection pulse C is sent to the CPU 32 and the LD drive circuit 3.
4. If tracking loss occurs during recording, the LD drive circuit 34 immediately lowers the laser drive current to the level during reproduction to prevent other data on the disk surface from being destroyed. In addition, the CPU 32
Decide that playback has failed and try again. however,
If the recording medium is the DRA%1 type, it is impossible to rewrite the recorded data, so the recording is repeated from the position where the track deviation occurred, as shown in FIG.

In addition, when reproducing images that have been recorded as shown in Fig. 5 due to the trunk coming off, S y, S
Every time the detection circuit 46 detects the Sy pattern, it is necessary to reset the subsequent data transfer to the frame memory 24.

In order to detect the off-track position during recording, it is sufficient to determine whether information has been recorded or not based on the envelope of the reproduced signal. Whether information has been recorded or not can also be determined from the reproduced subcode.

That is, since a subcode reproduced from a recorded area has a serial block number added to each block, it is only necessary to check whether the numbers are continuous or not.

Although the above description has been made using the CD format as an example, the present invention also applies to other formats (for example, Digital Audio
io Tape Recorder format), etc.

Furthermore, the present invention is applicable not only to optical disk devices as shown in this embodiment but also to magnetic disk devices.

〔Effect of the invention〕

As can be seen from the above description, the present invention provides an image recording and reproducing apparatus that can automatically try again without destroying other recording areas even if track deviation occurs during recording or reproduction. can be provided.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the configuration of an embodiment of the present invention, Figure 2 is the recording format of a compact disc, Figure 3 is the logical format of one block of a compact disc, and Figure 4 is the recording of still image data. FIG. 5 is a diagram showing an example of a recording format when a trunk disconnection occurs during recording and re-recording is performed. 1 (1-111 optical disk 12--spindle motor 14--optical R/W head 16-feeding mechanism 18-position detector 20--FG 32-CPU 34-
LD drive track circuit 36-・CLV servo circuit during recording 44
・-・CLV servo circuit during playback 48- Track・
Jump detection circuit patent applicant Canon Corporation

Claims (1)

[Claims] An image recording and reproducing device that forms a spiral recording track on a disk-shaped recording medium by recording image information from either the innermost circumference or the outermost circumference of the disk-shaped recording medium toward the other side. There is a recording/reproducing method for recording or reproducing image information on the disc-shaped recording medium.
a playback head; a head moving means for moving the position of the recording/playback head with respect to the disk-shaped recording medium;
tracking monitoring means for detecting the tracking state of the recording/playback head and outputting a tracking error signal when the head enters a tracking error state; If a tracking error signal is output from
An image recording/reproducing apparatus comprising: recording/reproducing operation control means for moving a reproducing head to a predetermined position on the disc-shaped recording medium and retrying a recording or reproducing operation.