JP2002260337A - Image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly record a dynamic image signal even when many defect areas are present in a magneto optical disk 30. SOLUTION: A plurality of free spaces are formed in the magneto optical disk 30, and a FAT(file allocation table) with which the free spaces can be specified and a defect list with which defect areas can be specified are recorded. When a dynamic image signal is recorded on the magneto optical disk 30, a system controller 32 creates a free space list by referring to the defect list and the FAT. A disk control circuit 24 records the dynamic image signal on each free space by referring to the free space list.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus, and more particularly to, for example, a digital camera, in which an image signal is recorded on a recording medium in which a plurality of free areas are formed and free area information on each free area is recorded. Record the
The present invention relates to an image recording device.

[0002]

BACKGROUND ART As a method of recording a signal on a recording medium,
MS-DOS format FAT (File Allocation
Table) method is well known. In the FAT system, a recording signal is handled in sector units. For this reason,
Even when the free areas are finely dispersed by repetition of recording and erasing, signals can be recorded without any problem as long as the total free area exceeds the signal size.

[0003]

However, if there is a defect in a part of the sector forming the empty area, it is necessary to perform a recording process so as to avoid the defective sector. Then
When the recording medium is a disk recording medium such as a magneto-optical disk or a hard disk, an effective recording speed is reduced by head seek. Therefore, when attempting to record a continuously captured moving image signal on a disk recording medium having many defective sectors, the effective recording speed may be lower than the moving image signal capturing speed, and the recording process may be broken.

[0004] Therefore, a main object of the present invention is to provide an image recording apparatus capable of appropriately recording a moving image signal even on a disk recording medium having many defects.

[0005]

SUMMARY OF THE INVENTION The present invention relates to an image recording apparatus for recording an image signal on a recording medium in which a plurality of free areas are formed and free area information on each free area is recorded. First detecting means for detecting a defective area from a recording medium, reading means for reading free area information from a recording medium, and creation of a list indicating recordable free areas based on the detection result of the first detecting means and free area information An image recording apparatus, comprising: recording means for recording an image signal in each recordable free area with reference to a list and a list.

[0006]

A plurality of free areas are formed on a recording medium, and free area information on each free area is recorded. When recording an image signal on such a recording medium,
First, the first detecting means detects a non-recordable defective area from the recording medium, and the reading means reads the free area information from the recording medium. The recordable free area list is created by the creating means based on the detection result of the first detecting means and the free area information. The recording means records the image signal in each recordable free area with reference to the created list.

When the recording medium records the defective area information on the defective area, the first detecting means reads the defective area information from the recording medium, and the creating means makes a list based on the read defective area information and the free area information. Create

In a preferred aspect, the recording medium has a substitute area for recording an image signal instead of the defective area, and the defective area information includes substitute area information on the substitute area. At this time, the creating unit creates the list by regarding the substitute area as a recordable free area.

In another preferred aspect, each time the recording of the image signal is completed, the image signal is reproduced by the second detecting means, and the defective area is detected. The updating means updates the defect area information based on the detection result of the second detecting means.

When one of the moving image mode for recording a moving image signal and the still image mode for recording a still image signal is selected, a different recording order is set for each of the recordable empty areas in the moving image mode and the still image mode. May be assigned.

[0011]

According to the present invention, a list of recordable areas is created based on a result of detection of a defective area and free area information, so that a moving image can be recorded even on a disk recording medium having many defects. The signal can be properly recorded.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0013]

Referring to FIG. 1, a digital camera 10 of this embodiment includes an image sensor 12 for photographing a subject. The image sensor 12 performs photoelectric conversion on the light image of the subject illuminated on the light receiving surface, and generates a charge (camera signal) corresponding to the subject image.

When the shutter button 36 is pressed while the still image mode is set by the recording mode switch 34, the system controller 32
Command to read all pixels of camera signal for screen. TG
Reference numeral 14 denotes the image sensor 1 for a period corresponding to one screen.
2 is driven by the all-pixel readout method. Thereby, a high-resolution camera signal generated on the light receiving surface is output from the image sensor 12.

On the other hand, when the moving image mode is set by the recording mode switch 34 and the shutter button 36 is pressed, the TG 14 performs the thinning-out reading of the camera signal.
Command 14 The TG 14 drives the image sensor 12 by the thinning-out reading method.
2 outputs a low-resolution camera signal. Note that the thinning-out reading is stopped when the shutter button 36 is pressed again.

The camera signal output from the image sensor 12 is subjected to well-known noise removal and level adjustment by a CDS / AGC circuit 16, and the camera signal subjected to such processing is converted by an A / D converter 18. It is converted to a digital signal. The A / D converted camera signal is
The signal is converted into a YUV signal by the signal processing circuit 20, and the YUV signal is subjected to JPEG compression. In the still image recording mode, only the YUV signal for one screen is obtained, so that the compressed YUV signal for one screen is generated based on the YUV signal for one screen. On the other hand, in the moving image recording mode, YUV signals for a plurality of screens are obtained. At this time, JPEG compression is performed for each screen, and compressed YUV signals for a plurality of screens are generated. The generated compressed YUV signal is written to the buffer memory 22 by the signal processing circuit 20.

The buffer memory 22 has a capacity capable of storing at least one screen of a high-resolution compressed YUV signal. All the compressed YUV signals of one screen generated in the still image mode are stored in the buffer memory 22. Is stored.

The compressed image signal stored in the buffer memory 22 is read out by the disk control circuit 24 and is read out by the optical pickup 26 and the magnetic head 28 by the FAT.
The data is recorded on the magneto-optical disk 30 in a system. In particular,
The disk control circuit 24 first detects an empty area from the magneto-optical disk 30 and places the optical pickup 2 in the detected empty area.
6 and the magnetic head 28 are moved. Subsequently, the compressed YUV signal is read from the buffer memory 22 to output a laser beam to the semiconductor laser 26 a provided in the optical pickup 26, and a recording current corresponding to the read compressed YUV signal is supplied to the magnetic head 28. As a result, the compressed YUV signal is recorded in the empty area. If the compressed YUV signal still remains in the buffer memory 22 even when the empty area is full, the disk control circuit 24
The empty area is detected again, and the optical pickup 26 and the magnetic head 28 are moved to the detected empty area. And
The remaining compressed YUV signal is read from the buffer memory 22, and the compressed image signal is recorded in a free area by the semiconductor laser 26a and the magnetic head 28. As a result, even when a plurality of free areas are discretely distributed, the compression Y
The UV signal is appropriately recorded in each empty area.

The recording surface of the magneto-optical disk 30 is divided into several tens to several hundreds of logical zones (LZ), and each logical zone has two data areas and two logical zones as shown in FIG. Formed by two alternative areas. In other words, the data area composed of 63 blocks and the replacement area composed of one block are alternately present, and one logical zone is formed by the data area and the substitution area of a total of 128 blocks.

The replacement area is an area for recording a signal in place of the defective sector or block when a defective sector or block described later exists in the data area. For this reason, unless there is a defective sector or a defective block, the replacement area is left empty. One block is composed of 16 sectors.

On the recording surface of the magneto-optical disk 30, defective sectors in which signals cannot be recorded occur due to scratches on the stamper during manufacturing, bubbles generated during the vapor deposition process, or scratches or dust generated during use. Therefore, a defect list L1 as shown in FIG. 3 is created at the manufacturing stage and recorded on the magneto-optical disk 30. The defect list L1 is a PDL (Primar
y Defect List) and SDL (Secondary Defect Lis)
t). The PDL is a list for registering addresses of defective sectors detected before shipment and the SDL is a list for registering addresses of defective blocks to which defective sectors detected during use belong, and a replacement area (“replacement destination block”) for replacing the defective blocks. ) Are registered.

During manufacturing, defects are detected in sector units. The replacement area has a capacity of 16 sectors, and the capacity shortage due to the defective sector can be sufficiently compensated for by the replacement area following the data area to which the defective sector belongs. Therefore, only the address of the defective sector is registered in the PDL. On the other hand, at the time of use (especially at the time of recording), defects are detected not in sectors but in blocks. There is a possibility that a defective sector also exists in a substitute area following a data area having a defective block, and such a substitute area cannot compensate for a defective block. In such a case, the capacity shortage due to the defective block is compensated for by a substitute area of a logical zone different from the logical zone to which the defective block belongs.
Therefore, the address to which the defective block belongs and the address of the replacement destination block that supplements the defective block are registered in the SDL.

When recording an image signal in a logical zone having a defective sector, the image signal is recorded in the data area and the replacement area in the order shown in FIG. That is, the image signal is recorded from the head of the data area to the sector immediately before the defective sector, and subsequently, from the sector next to the defective sector. An image signal of a size corresponding to the capacity of the defective sector is recorded in the replacement area.

When an image signal is recorded in a logical zone having a defective block, the image signal is recorded in the data area and the replacement area in the order shown in FIG. First, the image signal is recorded from the head of the data area to the sector immediately before the defective block, then jumps to the alternative area, and when the recording in the alternative area is completed, the image signal is recorded in the sector following the defective block. FIG. 5 shows an operation when a defective block and a replacement block exist in the same logical zone.

As described above, the addresses of the defective sector and the defective block are registered in the defect list L1, and the addresses are not reflected on the FAT. Therefore, F
When an empty area is detected only by referring to the AT,
A different empty area list L2 is created between the case where the empty area is detected with reference to the defect list L1 (especially the SDL). That is, when the free areas detected with reference to only the FAT are distributed as shown in FIG. 6, the free area list L2 is created as shown in FIG. 7, and the free area list L2 is detected with reference to the FAT and the defect list L1. If the free areas are distributed as shown in FIG. 8, the free area list L2 is created as shown in FIG.

Referring to FIG. 6, according to the FAT, free areas having different capacities are discretely distributed on the recording surface of the magneto-optical disk 30. At this time, in the free area list L2 based only on the FAT, as shown in FIG. 7, the starting address and free capacity of each free area to are registered, and the recording order in the moving image mode and the still image mode is assigned. .

Referring to FIG. 8, according to the FAT and defect list L1, free areas ~, -a to -c, and-are discretely distributed on the recording surface. Here, the vacant area-a is a vacant area existing before the defective block DB in the vacant area, the vacant area-b is a replacement block of the defective block DB, and the vacant area-c is a vacant area than the defective block DB. This is an empty area that exists later. At this time, in the free area list L2 based on the FAT and the defect list L1, as shown in FIG. 9, the free areas ~, -a to -c, and the start address and free capacity of each are registered. The recording order in the mode and the still image mode is assigned.

In FIGS. 7 and 9, in the still image mode, numbers are assigned in ascending order of free space, and in the moving image mode, numbers are assigned in ascending order of free space. This is because in the still image mode, the decrease in the effective recording rate due to the head seek does not pose a problem, whereas in the moving image mode, if the effective recording rate decreases due to the head seek, the recording process may fail. Because.

However, if there is a defective block in the empty area as shown in FIG. 8, a head seek to the replacement block-b is required at the time of recording in the empty area.
With the free area list L1 created based only on the AT, the problem of failure of the recording process in the moving image recording mode cannot be solved. For this reason, in this embodiment, the free area list L2 shown in FIG. 9 is created in consideration of both the FAT and the defect list L1. As a result, the compressed YUV signal for forming a moving image is appropriately
0 can be recorded.

Specifically, the system controller 32 processes the flowcharts shown in FIGS. First, a defect list read command is issued to the disk control circuit 24 in step S1. The disk control circuit 24 reads the defect list L1 from the magneto-optical disk 30 in response to this command, and returns the read defect list L1 to the system controller 32. In step S3, YES is determined in response to the return of the defect list L1, and in step S5, the returned defect list L1 is stored in the memory 38.

In step S7, a FAT read command is issued to the disk control circuit 24. The disk control circuit 24 responds to this command by
, And returns the read FAT to the system controller 32. In step S9, it is determined YES in response to the return of the FAT, and in step S11, the returned FAT is stored in the memory 38.

In step S13, the magneto-optical disk 30
A free area list L2 is created based on the defect list L1 and the FAT read from the. As a result, FIG.
A free area list L considering a defective block as shown in FIG.
2 is obtained. When the creation of the free area list L2 is completed, it is determined in step S15 whether or not a shooting instruction has been given. When the shutter button 36 is pressed, the flow advances to step S17 to determine the recording mode.

If the still image mode has been selected by the recording mode switch 34, step S1 is executed.
In step 9, the TG 14 is instructed to shoot a still image. The TG 14 captures an image of one screen, and reads out the generated camera signal by the all-pixels reading method. The buffer memory 22 stores a compressed YUV signal for one screen based on all-pixel reading.

In step S21, the buffer memory 22
Of the compressed YUV signal stored in the disk control circuit 24. The disk control circuit 24 refers to the recording order of the still images set in the free area list L2, and
Compress Y to each free area in order from the free area with the smallest capacity
Record the UV signal.

When the recording process is completed, a confirmation command is issued to the disk control circuit 24 in a step S23. The disk control circuit 24 reproduces the compressed YUV signal recorded immediately before from the magneto-optical disk 30 and determines whether still image data has been properly reproduced from each block.
Here, an OK signal is returned to the system controller 32 when appropriate reproduction processing has been performed on all blocks. However, when reproduction processing has not been appropriately performed on some blocks, the block (defective) The address of the block) and the address of a replacement block to replace the block) are returned to the system controller 32 together with the NG signal.

When the NG signal is returned, step S
The process proceeds from S25 to S27, and the defective block address and the replacement block address returned together with the NG signal are registered in the SDL of the defect list L1. That is, the defect list L1 is updated. In the following step S29, a free area list L2 is newly created in the same manner as in step S13 described above. When the creation of the free area list L2 is completed, the processing of steps S21 to S25 is executed again.

When the OK signal is returned from the disk control circuit 24, YES is determined in the step S25, and in a step S31, the FAT creation command is transmitted to the disk control circuit 2
Issue to 4. The disk control circuit 24 creates (updates) the FAT in response to this command, and returns the OK signal to the system controller 32 when the creation is completed.
The system controller 32 returns from step S33 to step S7 in response to the return of the OK signal.

On the other hand, if the shutter button 36 is pressed in the state where the moving image mode is selected, YES is determined in the step S17, a command to shoot a moving image is given to the TG 14 in a step S35, and the buffer memory 22 is Of the compressed YUV signal stored in the disk control circuit 24. The TG 14 repeatedly performs photographing, and reads out camera signals of each screen obtained by the thinning-out reading method. The compressed YUV signals for a plurality of screens are written in the buffer memory 22, and the disk control circuit 24 refers to the free area list L2 and
The UV signal is recorded on the magneto-optical disk 30. Compression YUV
The signal is recorded in each free area in the order of larger capacity in accordance with the moving image recording order set in the free area list L2.

In step S39, it is determined whether or not the shutter button 36 has been pressed again. If YES, the TG 14 and the disk control circuit 24 are instructed to stop the photographing process and the recording process in step S41. The TG 14 immediately stops shooting, and the disk control circuit 24 stops recording when the buffer memory 22 becomes empty. When the processing in step S41 is completed, steps S31 and S31
After the process at step S33, the process returns to step S7.

The processes in steps S13 and S29 follow a subroutine shown in FIG. First, at step S51, one free area is detected by referring to the FAT, and at step S53, the free area is compared with the SDL. As a result of this comparison, when a defective block exists in the detected empty area, the process proceeds from step S55 to step S57, and the empty area before and after the defective block is divided.

In a succeeding step S59, the free area after division and the replacement block detected from the SDL are registered in the free area list L2. In other words, each of the divided free space and the replacement destination block is a recordable free space,
The start address and free capacity of these recordable free areas are registered in the free area list L2.

On the other hand, if no defective block is found from the empty area as a result of the comparison processing in step S53, the empty area is set as a recordable empty area, and the start address and the empty capacity are stored in the empty area list. Registered in L2.

When the processing in step S59 or S63 is completed, it is determined in step S63 whether or not the detection of all free areas has been completed. If NO here, step S5
Returning to step 1, the above processing is repeated. On the other hand, if YES, the flow advances to step S65 to assign a number (order) according to the recording mode to each free area. That is, in the moving image mode, numbers are assigned in ascending order of capacity, and in the still image mode, numbers are assigned in ascending order of capacity. When the free area list L2 as shown in FIG. 9 is created in this way, the process returns to the routine in the upper hierarchy.

As can be seen from the above description, a plurality of empty areas are formed on the magneto-optical disk 30. The magneto-optical disk 30 also has a FAT that can specify each free area.
And a defect list L1 having PDL and SDL are recorded. The address of the defective sector is registered in the PDL.
In the DL, the address of the defective block and the address of the replacement block that replaces the defective block are registered.

When recording a compressed YUV signal (moving image signal or still image signal) on the magneto-optical disk 30, the system controller 32 reads the defect list L1 and the FAT from the magneto-optical disk 30 and reads out the read defect list L1. And a free area list L2 based on the FAT. The replacement destination block is also registered as a recordable free area in the free area list L2. Also, numbers are assigned to the recordable free areas in order of smaller capacity for recording still images, and numbers are assigned in order of larger capacity for recording of total images. The disk control circuit 24 refers to the free area list L2 and records the compressed YUV signal for forming a still image in each recordable free area in ascending order of capacity to form a moving image. With respect to the compressed YUV signal to be recorded, recording is performed in each recordable empty area in order from a larger capacity.

In the still image mode, each time the recording of the compressed YUV signal is completed, the compressed YUV signal is reproduced, and it is determined whether or not a defective block exists in the recorded area. When a defective block is detected,
The address of the defective block and the address of the replacement destination block are registered in the SDL.

As described above, since the free area list L2 is created based on the defect list L1 and the FAT, even when a large number of defective blocks exist on a disk recording medium such as the magneto-optical disk 30, the moving image signal L2 is generated. Can be appropriately recorded.

In this embodiment, the recording method is F
The AT method is adopted, but UDF (Univ.
ersal Disc Format). Further, in this embodiment, a description is given using a digital camera, but the present invention is also applicable to a stationary hard disk recorder. Further, the digital camera of this embodiment may be used as a surveillance camera.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is an illustrative view showing one example of a logical zone formed on a recording surface of a magneto-optical disk;

FIG. 3 is an illustrative view showing one example of a defect list;

FIG. 4 is an illustrative view showing one example of a recording operation when a defective sector exists in a logical zone;

FIG. 5 is an illustrative view showing one example of a recording operation when a defective block exists in a logical zone;

FIG. 6 is an illustrative view showing a distribution state of empty areas formed on the magneto-optical disk;

FIG. 7 is an illustrative view showing one example of a free area list created with reference to a FAT;

FIG. 8 is an illustrative view showing a distribution state of empty areas and defective blocks formed on the magneto-optical disk;

FIG. 9 is an illustrative view showing one example of a free area list created with reference to a FAT and a defect list;

FIG. 10 is a flowchart showing a part of the operation of the system controller.

FIG. 11 is a flowchart showing another portion of the operation of the system controller.

FIG. 12 is a flowchart showing another portion of the operation of the system controller.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Digital camera 22 ... Buffer memory 24 ... Disk control circuit 26 ... Optical pick-up 28 Magnetic head 30 ... Magneto-optical disk 32 ... System controller 34 ... Recording mode changeover switch 36 ... Shutter button 38 ... Memory

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Claims (7)

[Claims] 1. An image recording apparatus for recording an image signal on a recording medium in which a plurality of free areas are formed and free area information on each of the free areas is recorded, wherein an unrecordable defective area is removed from the recording medium. First to detect
Detecting means; reading means for reading the free area information from the recording medium; creating means for creating a list indicating recordable free areas based on the detection result of the first detecting means and the free area information; An image recording apparatus, comprising: recording means for recording the image signal in each of the recordable empty areas with reference to the recording area. 2. The recording medium records defect area information on the defect area, the first detecting means reads the defect area information from the recording medium, and the creating means records the defect area information and the free area information. The image recording apparatus according to claim 1, wherein the list is created based on the following. 3. The recording medium has a replacement area for recording the image signal in place of the defect area, the defect area information includes replacement area information on the replacement area, and the creating unit replaces the replacement area with the replacement area. 3. The image recording apparatus according to claim 2, wherein the list is created by regarding the recordable empty area as being available. 4. A second detecting means for reproducing the image signal every time the recording of the image signal is completed to detect the defective area, and for detecting the defective area information based on a detection result of the second detecting means. 4. The image recording apparatus according to claim 2, further comprising an updating unit for updating. 5. A selecting means for selecting one of a moving image mode for recording a moving image signal and a still image mode for recording a still image signal, and a different recording order between the moving image mode and the still image mode. Further comprising an allocating unit for allocating each of the recordable free areas to
The image recording apparatus according to claim 1. 6. The recording medium according to claim 1, wherein said recording medium is a disk.
6. The image recording apparatus according to any one of claims 1 to 5, 7. A digital camera comprising the image recording device according to claim 1.