JP2001351336A - Method and device for reproducing data, and method and device for recording data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save the recording area of a recording medium that is consumed in a data rewrite mode by referring to the contents of data recorded in the past. SOLUTION: A control part 24 retrieves the preceding VAT ICB. In other words, the retrieval is carried out from the VAT ICB which is recorded at the final end of the recorded area of a recording medium toward the recording start point of the recorded area. The VAT ICB that appears first in the said retrieval is read and expanded in a DRAM, and the VAT ICB expanded in DRAM is written after the VAT ICB recorded at the final end of the recorded area of the recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data reproducing method and apparatus, and a data recording method and apparatus.
The present invention relates to a data reproducing method and apparatus for managing a file by referring to a virtual address table other than a virtual address table described at the end of a recording position of a recording medium, and a data recording method and apparatus.

[0002]

2. Description of the Related Art A so-called CD to which optical reading is applied.
(Compact Disc).
Recorded as an optical disk. ) Has a large storage capacity and allows random access. In addition, since optical reading is non-contact, there is no danger such as head crash or wear and damage due to reading as compared with a contact type recording medium such as a magnetic tape. Also, because the disc surface is sturdy,
There is less danger of accidental data loss. An optical disc having many advantages as described above is an excellent recording medium as a memory around a computer and in data production and data storage.

In recent years, CD-Rs (Compact Disc-Rec
A recording / reproducing apparatus using a write-once optical disc called ordable) has been developed. Some of these CD-Rs can easily be written to all standard formats used on compact discs, such as CD-ROM, CD-ROM / XA, CD-I, and CD-DA. Some can. CD-Rs are mounted on electronic devices instead of conventional magnetic tapes, magnetic disks, etc., to record and / or record data.
Or, it is being used as a recording / reproducing device for reproducing.

[0004] As a standard relating to recording and / or reproduction using an optical disk, US-based OSTA (Optical Storage Technology).
UDF (Universal) defined by
Disk Format).

A so-called CD-R conforming to such UDF
In a write-once recording medium such as (Compact Disk-Recordable), packet writing is used when writing data. Packet writing is a link block before data and four run-ins.
Two run-outs (Run-Ou) at the end of the area and data
t) Writing is performed as a packet structure having an area. In addition to the data area, seven blocks are used as a linking area (Linking Area) which is a joining area between adjacent packets.

In UDF, instead of directly managing directory and file management information as actual recording locations (logical addresses), a file identification descriptor (FID: File Iden) is used.
tifier Descriptor), virtual allocation table (VAT: Vi)
rtual Allocation Table), file entry ICB (Fil
e Entry Information Control Block).

[0007] VAT is a technique for treating a sequential write medium as if it were a random read / write medium, and includes a logical address where a file is actually recorded and a virtual address corresponding to the logical address. The address is managed as a correspondence table.

That is, the UDF indirectly refers to the directory and file position information. The position of VAT is
It can be placed freely in the packet structure, but VAT points to VAT ICB (Virtual Allocation Table Inform)
ation Control Block) is determined so as to be always located at a position returned by the linking area from the last sector recorded on the recording medium.

In a file system conforming to the UDF, the latest VAT ICB is always described at a position that is returned from the last address position of the disk by 7 blocks prepared as a linking area. Therefore, in the UDF, first, the virtual address can be converted into a real address (logical address) by reading the VAT indicated by the VAT ICB.

[0010] In particular, it is impossible for a write-once recording medium to physically erase data once recorded or to overwrite data already recorded. Therefore, when erasing data, logical deletion is performed by setting the delete bit of the characteristic existing in the FID of the file to be erased. In addition, the directory ICB, VAT ICB, VAT, etc. are rewritten in accordance with this, and data is logically erased by appending them.

[0011]

In a write-once recording medium in which files are managed by the above-mentioned conventional UDF-compliant file system, for example, 200
Consider a case in which all zero files are deleted.

When the 2000 files are deleted, the directory ICB = 1 block (1 block = 2048 bytes), FID = 63 blocks, VAT ICB = 1 block, VAT = 4 blocks, linking area = 7 blocks Consume. Therefore, an operation for deleting a file consumes a total of 76 blocks, that is, a recording area corresponding to about 156 Kbytes.

As described above, in the conventional file system conforming to the UDF, there is a problem that erasing a file wastes the recording capacity of a recording medium.

In a write-once type recording medium based on a UDF-compliant file system, a previously recorded data is logically erased even though previously recorded data remains without being physically erased. There is a problem that the file cannot be referenced again.

The present invention has been proposed in view of such a conventional situation. Data recorded in the past can be referred to, and the recording area of the recording medium consumed at the time of data rewriting can be saved. It is an object of the present invention to provide a data reproducing method and apparatus, and a data recording method and apparatus capable of restoring a past recording state.

[0016]

In order to achieve the above-mentioned object, a data reproducing method according to the present invention comprises: a real address indicating a recording position of a file in which data is stored; What is claimed is: 1. A data reproducing method for reproducing data by managing files based on a virtual allocation table indicating a correspondence with a virtual address whose position is indicated, comprising: a virtual allocation recorded at a final end of a recorded area of a recording medium. It is characterized in that a virtual allocation table other than the table is read.

Such a data reproducing method refers to data recorded in the past by reading a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium.

Further, the data reproducing apparatus according to the present invention provides a virtual address indicating a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data reproducing apparatus that manages a file based on an allocation table and reproduces data by performing control for reading a virtual allocation table other than the virtual allocation table recorded at the last end of a recorded area of a recording medium. It is characterized by having control means.

Such a data reproducing apparatus refers to data recorded in the past by reading a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium.

In order to achieve the above-mentioned object, a data recording method according to the present invention comprises a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data recording method for managing data and recording data based on a virtual allocation table indicating a correspondence with an address, wherein the data is read out from a virtual allocation table recorded on a recording medium, and the last data in a recorded area of the recording medium is read out. It is characterized by appending to the end.

According to such a data recording method, the past recording state is restored by reading out the virtual allocation table recorded on the recording medium and successively adding it to the last end of the recorded area of the recording medium.

Further, the data recording apparatus according to the present invention provides a virtual address indicating a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data recording apparatus that manages files based on an allocation table and records data, reads out a virtual allocation table recorded on a recording medium, and additionally writes the virtual allocation table to the last end of a recorded area of the recording medium. Is characterized by having control means for performing the control of (1).

Here, the virtual allocation table to be read is the virtual allocation table recorded at the last end of the recorded area of the recording medium, and the virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. It may be a virtual allocation table.

Such a data recording apparatus restores a past recording state by reading out the virtual allocation table recorded on the recording medium, and appending it to the last end of the recorded area of the recording medium.

[0025]

Embodiments of the present invention will be described below in detail with reference to the drawings.

A digital still camera shown as one configuration example of an embodiment of the present invention is a UDF (Universal Disk Format).
Based on a file system conforming to t), writing of captured image data and reading of image data from the recording medium are performed on a write-once recording medium, and the image data is stored. When writing and reading the file, the virtual allocation table recorded at the last end of the recorded area of the recording medium, or the virtual allocation table other than this virtual allocation table, is read to read the past allocation recorded on the recording medium. The data can be referred to.

UDF (Universal Disk Format) is a CD-R
(Compact Disc-Recordable), WORM (Write-Once Read)
-Many optical disk), CD-R / RW (Compact Disc-Record)
able / Rewritable), MO (Magnet Optical Disk), DVD
(Digital Versatile Disk) is one of the definitions for describing the character codes of file names and file attributes that can be used mutually for various media such as OSTA (Optica).
l Storage Technology Association).

That is, the UDF is a file system that can be written from any OS and the written file can be reproduced on any OS without a special reader program.

In UDF, a main data structure is a file entry information control block (ICB).
k) is used. In UDF, every file and directory has its own ICB. In the embodiment of the present invention, a file storing actual data such as image data of a captured image is generally written before an ICB that defines the file. When placed on the (data stream), the ICB can include a list of those extents.

In UDF, VAT (Virtual Allocation Tabl)
Using a mapping table called e), a sequential number (virtual address) for a virtual reference is assigned to each file. Whereas a file system conforming to the international standard ISO9660 refers to each file or directory on a recording medium directly by a logical address, UDF
Is referred by the virtual address as described above. VAT
Can be placed anywhere in the truck,
Further, the VAT is referred to by a VAT ICB indicating the location of the VAT.

In the UDF, it is determined that the VAT ICB is located at the last physical address recorded on the recording medium. The VAT is divided and arranged on a plurality of extents, but the VAT ICB includes a VAT extent list. Thus, in a UDF, if a file is modified in any way, the entire set of file pointers does not need to be changed, and eventually only the VAT ICB can be reached to the changed file .

In a UDF-compliant file system, the structure of a unit (hereinafter, referred to as a volume) for managing a detachable recording medium that accommodates a file or the like is as shown in FIG.

In a file system conforming to the UDF, a BEAD (Beginning) in an extended area recorded after 16 sectors when the beginning of a session is set to 0 sector.
Extended Area Descriptor) and TEAD (Terminating E)
VSD (Volume S) sandwiched between xtended Area Descriptor
tructure Descriptor) contains information for recognizing the UDF file system.

In a UDF-compliant file system, an AVDP (Anchor Volume) in which an optical head reads first to reach a file in a state where data is written to a recording medium and before closing a session.
Descriptor Pointer). AVDP has a logical block number (LBN) of 512 when the beginning of a session is 0 sector.
It is described in the area of the sector.

That is, if an AVDP exists in the sector 512, it is understood that the AVDP is recorded based on a UDF-compliant file system. AVDP is composed of LBN = 256 sectors and LBN =
(LBN of last write sector) Described in two sectors of -256 sectors. After the closed session operation, the AVDP described in the sector 512 is not used for reading. AVDP stands for Volume Descriptor (hereinafter VDS: Volume Descriptor).
Described as scriptor Sequence. ). V
The DS group is described from sector 512 onward.

The VDS is a descriptor indicating information on the contents of the volume structure. The VDS has a basic volume descriptor and a logical volume descriptor (hereinafter referred to as LVD: Logical Volume Descriptor).
Write as ume Discription. ), Volume information such as an application volume descriptor, a virtual partition descriptor, and a real partition descriptor, and partition information.

There are two partitions, a real partition and a virtual partition. The real partition contains the actual logical address of the data recorded on the recording medium. On the other hand, the virtual partition is a table based on the virtual address of the data, and is a division of the area when the entire recording area of the recording medium is remapped from the physical address to the virtual address. The virtual partition is determined by VAT.

Further, two descriptors indicating a real partition and a virtual partition are placed in the VDS.
If the partition number is 0, the file system refers to the real partition, that is, the actual logical address, and if it is 1, the file system refers to the virtual partition (VAT).

The LVD in the VDS indicates a set of file set descriptors (hereinafter, referred to as FSDS: File Set Descriptor Sequence), that is, a set of file sets existing in the volume. Each FSDS is RDICB
(Root Directory Information Control Block), and the RDICB contains information such as specific directory names and file names.

A UDF-compliant file system suitable for packet writing has two unique data structures. File Entry ICB (File Entry ICB) for identifying each file existing in the file system
And a file identifier (FID)
Descriptor. ). The FID indicates the physical address of the file entry ICB. Or, via VAT,
Indirectly points to the file entry ICB.

The directory referred to by the RDICB is configured as a table in which related FIDs are collected. The file entry ICB contains all extent lists, dates, file attributes, and the like of the stored file. Therefore, the content of this file entry ICB is a physical address that may change when the file is changed or edited.

The FID points to the file entry ICB, and the file entry referenced by the file entry ICB points to an actual file. Since a directory is a type of file, a file entry can also point to a directory. Thus, the file system conforming to the UDF has a tree-like hierarchical structure.

As described above, the root directory can be referred to by RDICB. In the root directory, the FID for referring to the file entry ICB
Or contains an FID pointing to the directory entry ICB.

The FID has information such as “partition 1 / block 200”. If the partition is 1, since it is a virtual partition, the file system directly accesses the logical address to search for a file.
Do not go to 200. Instead, it will first reference the VAT and point to the logical address via the VAT.

As a result of the above file system, the UDF executes an operation schematically shown in FIG. 2 in order to seek a file.

The optical head first reads the last area of the recorded area of the disk. Here is VAT ICB
Is described. VAT is read from VAT ICB.

Subsequently, the optical head refers to the AVDP in the sector 256. Next, VDS described in AVDP is referred to.

From the VDS, it is determined whether the partition is a real partition or a virtual partition.

Further, the FSDS is referred from the VDS. The FSDS indicates the RDICB, and the RDICB indicates the root directory. The root directory contains an FID indicating the ID of each file.

Finally, if the partition flag of the VDS of the root directory constituted by the FID is a real partition, the physical address of the file entry ICB is directly referred to. If the flag is a virtual partition, File entry ICB via VAT
To the desired file.

By providing a VAT between the FID and the file entry ICB, even if the file entry ICB is rewritten, the file entry ICB is replaced on the VAT to virtually replace the file entry ICB.
It can be treated as if the ICB was rewritten.

Therefore, even if the location of the file entry ICB is changed due to, for example, changing the contents of the root directory, it is not necessary to rewrite the FID if the VAT is changed.

In the file system conforming to the UDF, by performing the above-described seek operation, it is possible to treat a sequential write recording medium as if it were a random read / write recording medium.

Next, a specific configuration of the digital still camera shown as one configuration example of the embodiment of the present invention will be described with reference to FIG. The digital still camera, for example, writes and reads data to and from a recording medium. Here, as a write-once recording medium, a so-called CD-R (Compact Diode) having a disk shape is used.
sc-Recordable).

The digital still camera 1 includes an image pickup section 10 for picking up an image of a subject, and an image signal processing section 1 for converting an image signal from the image pickup section 10.
1, a display unit 12 for displaying operation information for operating the digital still camera 1, an image signal, and the like, and an OP (Opti) for writing and / or reading from a recording medium described later.
cal Pickup) section 13, an RF processing section 14 for performing RF processing on a read signal, a servo signal processing section 15 for generating a servo signal from each signal from the RF processing section 14, and a servo signal processing section 1.
An analog filter processing unit 16 that generates an analog signal for controlling each driver based on the signal from the control unit 5;
A signal processing unit 17 that processes a read signal from a recording medium described later, a spindle driver 18 that controls the rotation of a spindle motor, a sled driver 19 that controls the operation of a sled motor, and swings the objective lens of the OP unit 13 A tracking driver 20 for controlling the focus of a beam by moving an objective lens of the OP unit 13 in the vertical direction with respect to the disk-shaped recording medium; a spindle motor 22 for driving the disk-shaped recording medium; Motor 13 for moving the recording medium 13 in the radial direction of the recording medium
And a control unit 24 for controlling each unit.
, Writing of captured image data and reading of image data.

The imaging unit 10 includes a lens unit 30 for capturing an image of a subject and a charge-coupled device (hereinafter, referred to as a charge-coupled device) for generating an image signal.
Notated as CCD. ) 31, a sampling / hold (hereinafter, referred to as S / H) 32, and an A / D conversion circuit 33 for converting an image signal into a digital signal. CCD 31
An image signal is generated from the subject image from the lens unit 30, and the generated image signal is supplied to the S / H circuit 32. S / H circuit 3
2 samples and holds the image signal from the CCD 31 and supplies it to the A / D conversion circuit 33. The A / D conversion circuit 33 converts the image signal from the S / H circuit 32 into a digital signal and supplies the digital signal to the image signal operation processing unit 11.

The image signal arithmetic processing unit 11 is controlled by the CPU to convert the digital image signal from the imaging unit 10 into RG signals.
It performs image processing such as color standard form conversion from B signal to color difference / luminance signal, white balance processing, γ correction, reduced image processing, JPEG compression processing and the like. The processed image signal is supplied to the signal processing unit 17. Further, the image signal arithmetic processing unit 11
Supplies the processed image signal to the display unit 12.

The display unit 12 is, for example, a liquid crystal display (LCD), and displays an image signal from the image signal processing operation unit.

The OP (Optical Pickup) unit 13 includes an objective lens, a laser diode (LD), a laser diode driver (LDdrv), and a photodetect IC (Photo Detect I).
C), including a half mirror, etc., detects an optical signal and outputs it to the RF processing unit 14. Further, when recording on the recording medium 25, a laser blinking / driving signal (DECEFMW) from the signal processing unit 17 necessary for pit formation, a signal (write strategy) indicating an optimum value of laser intensity and blinking, etc. The data is written to the recording medium 25 based on.

The RF processing unit 14 samples and holds the eight signals consisting of the beam signal, the side signal, and the main signal detected from the OP unit 13, performs an arithmetic operation,
FE (focus error), TE (tracking error), MIRR (mirror),
It generates signals such as ATIP (Absolute Time In Pregroove) and a read main signal. The RF processing unit 14 outputs the FMDT (Frequency Modulation Data), FMCK (Freque
ncy Modulation Clock), TE, FE, servo signal processing unit 1
5 and outputs an optimum value (OPC: Optical Power Calibration) signal of laser intensity and a laser blinking / driving signal detected by the test writing to the signal processing unit 17.
Is output to the control unit 24.

The servo signal processing unit 15 receives the FMDT (Frequency Modulation Data) and FMCK (Frequency
ency Modulation Clock), TE, FE, and control unit 2
4 to generate signals for controlling various servos unique to the optical disk, and output the signals to the analog filter processing unit 16.

The analog filter processing section 16 generates analog signals from various servo control signals from the servo signal processing section 15 and outputs the analog signals to the spindle driver 18, thread driver 19, tracking driver 20 and focus driver 21.

The signal processing unit 17 is controlled by the control unit 24 and receives the OPC and DECFFM from the RF processing unit 14 to perform processing such as CIRC decoding and encoding, write strategy, ADdr decoding, asymmetry, and running OPC. . When writing data to the recording medium, a signal such as a laser blinking / driving signal and a signal indicating an optimum value of the laser intensity is output to the OP unit 13.

The spindle driver 18 controls the rotation of the spindle motor 22 based on a signal from the analog filter processing section 16.

The thread driver 19 is controlled by the thread motor 23 based on a signal from the analog filter processing unit 16.
Control the thread behavior of

The tracking driver 20 oscillates the OP unit 13 based on a signal from the analog filter processing unit 16 to control the position of a beam spot irradiated on the disk surface of the recording medium 25.

The focus driver 21 controls the focus adjustment of the laser by moving the OP unit 13 in a direction perpendicular to the disk surface of the recording medium 25 based on the signal from the analog filter processing unit 16.

The spindle motor 22 rotates the recording medium based on a signal from the spindle driver 18.

The thread motor 23 performs a thread operation of the OP unit 13 based on a signal from the thread driver 19.

The control unit 24 includes a program memory for storing programs for performing various processes, and a DRAM as a work area for temporarily storing the VAT ICB and various data.
(Dynamic Random Access Memory), a non-volatile memory such as ROM and EPROM, and a CPU, and controls reading of VAT ICB and writing of VAT ICB. The control unit 24 controls each unit.

Here, the DRAM is specifically used as a work area for temporarily expanding the VAT ICB extracted from the recording medium. In addition, DRAM is updated every time a file or directory is updated, added, deleted, etc.
The correspondence table between the digital still camera 1 and the logical address on the recording medium where the virtual partition is started
Is stored until immediately before the main power of the device is turned off.

The recording medium 25 is a write-once recording medium for writing and reading data based on a UDF-compliant file system, and has a so-called disk shape.
CD-R (Compact Disc-Recordable).

In the digital still camera 1 having the function as the digital still camera configured as described above, the operation of each component when reading the signal recorded on the recording medium 25 will be described.

The light of the laser diode reflected from the disk surface of the recording medium 25 is read by the lens optical system of the OP unit 13. Light from the lens optics is converted to PDIC (Photo De
tectIC), is converted into an electric signal, is sampled and held in the RF processing unit 14, and focus error (FE), tracking error (TE), mirror (MIRR), ATIP (Absolute Time In P
regroove), a signal such as a read main signal is generated by arithmetic processing.

First, the focus error obtained by the RF processing unit 14 is determined by the servo signal processing unit 15 (Digital Servo
After the characteristic is adjusted by the processor, the signal is input to the focus driver 21 through the analog filter processing unit 16 (Analog Filter Block). Focus driver 2
1 moves the lens drive focus coil (not shown) of the OP unit 13 in the vertical direction to correct the focus shift.

Similarly, the tracking error obtained by the RF processing unit 14 is determined by the servo signal processing unit 15 (Digital Serv.
o Processor) to extract the AC component and apply digital filter processing. Thereafter, the signal passes through the analog filter processing unit 16 and is input to the tracking driver 20.
The tracking driver 20 finely moves the lens drive tracking coil of the OP unit 13 in the radial direction to correct the tracking deviation.

The tracking error obtained by the RF processing unit 14 is subjected to DC component extraction by the servo signal processing unit 15 and subjected to digital filter processing. After that, the thread driver 1 passes through the analog filter processing unit 16.
9 is input. The thread driver 19 operates the thread motor, moves the entire OP unit 13 in the radial direction of the recording medium, and corrects the deviation of the thread operation. During the seek operation, the sled motor is forcibly driven by intentionally applying the sled control voltage from the outside.

As described above, the tracking operation in which only the lens is finely moved in the radial direction based on the AC component of the tracking error is performed, and the sled operation for moving the entire OP unit 13 in the radial direction based on the DC component is performed. Will be

Since the detection signal (mirror) of the change in the reflectance of the recording medium output from the RF processing unit 14 is detected when the OP unit 13 crosses a track, the CPU counts the number of mirrors. It detects the current seek position and reading position, and starts and stops the optical pickup operation.

The control of the spindle motor 22 is performed by the ATIP (Ab
solute Time In Pregroove) processing.
In a meandering groove called a wobble groove written on a recording medium, time information is recorded by FM modulation of +/- 1 KHz at a center frequency of 22.05 KHz in a radial direction. Modulated is a bi-phase modulated ATIP (Ab
solute Time In Pregroove).

When the focus and tracking are matched, the RF processing unit 14 extracts a wobble signal from a predetermined combination of the eight input signals. FM demodulation, AT
It is subjected to IP decoding, and extracted as a clock signal (FMCK) corresponding to the center frequency and time information (FMDT).

The FMDT includes a servo signal processing unit 15 (Servo Pr.
ocessor), which is stored in a predetermined register classified as an absolute time position of the medium, that is, an address and other additional information. In response, the CPU reads via the BUS.

At the time of reading operation, a signal corresponding to a recording pit is extracted from a predetermined combination of eight signals by the RF processing unit 14, and is subjected to equalizer processing.
Fourteen Moduration) Signal processing unit 1 in signal format
7 is supplied. In the signal processing unit 17, CIRC (Cross Inte
(rleave Reed-Solomon Code) to perform decoding to obtain desired data.

Next, the write operation will be described. In the writing operation, first, the pickup is moved to the lead-in area to read the ATIP information. Further, the part of the special information 2 is read therefrom, and the start position of the lead-in area is known. The start position is usually stored as time information. The information written in the special information 2 corresponds to the individual identification code of the recording medium.

In the recording medium reading apparatus, a write strategy parameter corresponding to the individual identification code and other related parameters are stored in advance as a table. The write strategy is a technique for correcting a laser pulse at the time of writing in the time direction and the level direction for each pit so that the pit size after writing satisfies the standard. This correction parameter is prepared in advance for each recording medium.

Next, an OPC (Optical Power Caribration) operation for determining the optimum value of the laser output is performed. While the above-described write strategy is the detailed control of the laser for each write pit, the OPC is an operation for calculating an overall optimum value. By performing OPC, a write set value corresponding to an ideal read target value is obtained.

The data is written by compressing the photographed image data prepared in the RAM into a CI in the signal processor.
After performing the RC and EFM encoding processes, the laser blinking / driving signal (DECEFMW) required for pit formation and the (write strategy) signal indicating the optimum value of the laser intensity are input to the laser driver of the OP unit.

At this time, FMDT obtained by decoding ATIP
Writing is performed at a predetermined position in timing along a file system based on an address in a frame unit obtained from a signal.

In the first writing, writing is started from a position where an area of about 20 Mbytes serving as a lead-in area is skipped in a subsequent close session.

Next, a description will be given of how the photographed image data is written to the CD-R when photographing is performed using the digital still camera 1, with reference to FIG. FIG. 4 shows image data written to the recording medium 25 (CD-R) immediately after the photographing of the (N + X) th sheet has been performed after the photographing of the Nth sheet.

When the photographing is performed, the laser light is scanned spirally from the inner periphery to the outer periphery of the surface of the CD-R disk with the center of the disk as an axis, and the image data packets captured are added as pits.

The physical areas 100 and 101 indicate areas in which image data corresponding to the N-th and (N + X) -th sheets, respectively, have been written. FIG. 4 shows that the N-th image data is written from the inner periphery of the disk and the (N + X) -th image data is written from the outer periphery of the disk.

The structure of the packet data of the captured image written at this time will be described with reference to FIG. The volume 102 shown in FIG. 4 records the Nth to (N + X) th image data written in the recording space from the inner peripheral side to the outer peripheral side of the recording medium 25 in the virtual logical address space in order. And a virtual section (virtual partition) of the UDF in which captured image data is written.

Therefore, the direction in which the N-th image data 103 advances to the (N + X) -th image data 104 corresponds to the track direction in which the recording medium 25 spirally moves from the inner circumference to the outer circumference of the disk. ing.

The volume structure of the image data is schematically described corresponding to the virtual address space.

Joined record part (Link Block) 105, 10
Reference numerals 6, 107, and 108 each have an area for seven blocks, and are so-called joints when connecting sessions.

The segment 109 is the substance of the file containing the image data of the N-th frame.
Reference numeral 10 denotes an entity of a file including image data of the (N + X) -th image.

The segment 111 includes, in the file system hierarchy, a file entry ICB for a directory to which the substance of the Nth image data file included in the segment 109 belongs, and a file identification descriptor (FID).
Column is included. The file identification descriptor includes identification character string information for identifying a specific file.

The segment 112 includes only the file entry ICB for the directory to which the (N + X) th image data file included in the segment 110 belongs. Further, the segment 113 includes a column of a file identification descriptor. As described above, when the number of file identification descriptors is large, as shown in the segments 112 and 113, the file identification descriptor sequence is stored in a logical block different from the file entry ICB.

The segments 114 and 115 include the file entry ICB including the location of the file entity, file creation / update date / time information, authority (permission) information, and the like.
(ICB; Information Control Block). The position of the file entry ICB can be specified by the above-described file identification descriptor corresponding to the file entry ICB on a one-to-one basis. For the correspondence between the two, an address reference expression to a virtual space is usually used.

A segment 116 has a virtual allocation table.
ICB (VAT ICB) is included. VAT ICB is a virtual address space, a virtual address in the virtual partition of UDF, and a CD-
Stores information for associating actual logical block addresses on R, and the VAT ICB is updated by adding or changing a file entity.

The segment 117 includes the latest packet data of the (N + X) -th image captured last.
VAT is recorded.

The segment 118 and subsequent segments represent unrecorded sectors of the recording medium 25.

FIG. 4 shows that the session including the captured image data is not closed and can be additionally written.

Next, the operation of the digital still camera 1 referring to past recorded data will be described in detail with reference to FIG. FIG. 5A shows the state at the time of initialization (initialization).
The structure of the UDF volume is shown. FIG. 5B shows a UD in which a plurality of images are captured from the initialized state, and image data is additionally written in the captured order.
The volume structure of F is shown. In FIG. 5 (c),
The virtual allocation volume (VAT ICB) recorded at the end of the recorded area is read and changed, a new VAT ICB is generated, and the volume structure of the UDF when added to the current recording end is shown.

As shown in FIG. 5C, the control unit 24
The latest VAT ICB is read out, the VAT ICB is changed based on the change in the recorded contents, and a VAT ICB indicating the state of the new recorded contents is generated and added.

As a result, the directories ICB, FID, VAT
The recorded contents can be changed without rewriting all of the ICB, VAT, and linking area.

Next, the case where the digital still camera 1 refers to the file once deleted will be specifically described with reference to FIGS. 6 and 7. FIG.

FIG. 6A shows the structure of the UDF volume at the time of initialization (initialization). FIG.
(B) shows a volume structure of a UDF in which a plurality of images are captured from the initialized state, and image data is additionally written in the order in which the images were captured. FIG.
(C) shows the volume structure of the UDF when the VAT ICB immediately before the latest VAT ICB is read and added to the current recording end.

A specific operation of the control unit 24 at this time will be described with reference to FIG. In the following processing, the previous VAT ICB
(VAT ICB one before the latest VAT ICB) is referred to.

In step S1, the control unit 24 searches the previous VAT ICB. Specifically, a search is made from the VAT ICB recorded at the end of the recorded area of the recording medium in the direction of the recording start point of the recorded area.

In step S2, the control unit 24 searches the VAT ICB recorded at the last end of the recorded area from the VAT ICB toward the recording start point of the recorded area for the first time.
Read the ICB and expand it in memory.

At step S3, the control unit 24 sets the DR
A control signal for additionally writing the VAT ICB developed on the AM following the VAT ICB recorded at the last end of the recorded area of the recording medium is generated.

As described above, by searching and reading the previous VAT ICB, it is possible to refer to the recording state immediately before the latest VAT ICB. Also, this VAT
By adding the ICB to the last end of the recorded area, the previous recorded state can be restored.

In this case, the case where the previous VAT ICB is read has been described.
It is also possible to read the T ICB.

Next, a process for returning the recording medium on which data is recorded to the state at the time of initialization will be specifically described with reference to FIGS.

FIG. 8A shows the structure of the UDF volume at the time of initialization (initialization). FIG.
(B) shows the volume structure of a UDF in which a plurality of images are captured from the initialized state and image data is additionally written in the order in which the images were captured. FIG.
(C) shows the volume structure of the UDF when the VAT ICB described at the time of initialization is read out and this VAT ICB is added to the current end of recording.

The specific operation of the control unit 24 at this time will be described with reference to FIG. In step S10, the control unit 24 searches the VAT ICB at the time of initialization. Specifically, 5
A search is made from the AVDP described in 12 sectors toward the end of the recorded area.

At step S11, the control unit 24
The VAT ICB that appears for the first time after being searched from the AVDP toward the end of the recorded area is read and expanded in the DRAM.

In step S12, the control unit 24
A control signal for additionally writing the VAT ICB developed in the DRAM following the VAT ICB recorded at the last end of the recorded area of the recording medium is generated.

As described above, the VAT IC at the time of initialization
By reading B and appending it to the last end of the recorded area, it is possible to restore the state of the blank disk on which no data is recorded.

At this time, consider a case where the above-mentioned 2000 files are deleted. In the conventional file system, a recording area of 76 blocks (= 156 Kbytes) was consumed. On the other hand, when the VAT ICB at the time of initialization was copied to the last end, only 8 blocks were consumed. Consumption space at the time of deletion is saved. Further, at this time, since the operation relating to the deletion is omitted, the processing time is reduced.

Next, a case where the authentication information is recorded in the VAT ICB to restrict access to the entire session including the VAT ICB will be specifically described with reference to FIG.

First, after going through steps S10 and S11 for returning to the state at the time of initialization, step S10
At 20, the VAT ICB at the time of initialization, that is, the VAT ICB that appears for the first time from the AVDP described in 512 sectors toward the end of the recorded area is expanded in the DRAM.

In step S21, the Implementation Use indicated by the Extended Attributes in this VAT ICB
It is determined whether or not a protect mode bit is set in Attributes. If the protection mode bit is set, the process ends because the protection has already been performed. Here, Imp indicated by Extended Attributes
The lementation Use Attributes are areas where the contents can be freely described.

On the other hand, if the protect mode bit is not set, in step S22, Ext in the VAT ICB
Implementation Use Attri indicated by ended Attributes
Set protect mode bit in butes.

Subsequently, in step S23, VAT IC
Implementation U indicated by Extended Attributes in B
Encrypt and describe the password in se Attributes.

In step S24, the current VAT ICB
Is described in Implementation Use Attributes.

In step S25, the VAT ICB changed by the above operation on the DRAM is added to the last end of the recorded area, and the process is terminated.

A case where a file whose access is restricted based on the authentication information described in the VAT ICB as described above will be specifically described with reference to FIG.

First, after steps S10 and S11 for returning to the state at the time of initialization described above, step S11 is performed.
In step 30, the VAT ICB at the time of initialization, that is, the VAT ICB that appears for the first time from the AVDP described in 512 sectors toward the end of the recorded area is developed in the DRAM.

In step S31, the Implementation Use indicated by the Extended Attributes in this VAT ICB
It is determined whether or not a protect mode bit is set in Attributes. If the protect mode bit is not set, normal processing is performed.

If the protection mode bit is set, the input of the password is requested in step S32.

In step S33, the input password and the Extended Attributes in the VAT ICB indicate
It is determined whether the password encrypted and described in the Implementation Use Attributes is the same.

If the passwords are not the same, step S
Returning to 32, the user is required to input a password.

On the other hand, if the passwords are the same, the flow advances to step S34 to expand the VAT ICB in the DRAM by referring to the real address of the VAT ICB in the Implementation Use Attributes described in the step S24. .

In step S35, the data has been expanded to the DRAM.
The VAT ICB is added continuously to the last end of the recorded area, and the process ends.

As described above, the Extended Attr in the VAT ICB
A protection mode flag is provided in the Implementation Use Attributes pointed to by ibutes, and identification information such as a password is encrypted and described, so that the desired section can be referred to only when authentication is confirmed. Access can be controlled.

In the embodiment of the present invention, a digital still camera having the functions of the data reproducing method and apparatus and the data recording method and apparatus according to the present invention has been described, but other electronic devices may be used. Absent.

It should be noted that the present invention is not limited to only the above-described embodiment, and it is needless to say that various modifications can be made without departing from the spirit of the present invention.

[0141]

According to the data reproducing method of the present invention, a virtual address indicating a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of a file is provided. A data reproducing method for reproducing data by managing files based on an allocation table, wherein a virtual allocation table other than the virtual allocation table recorded at the last end of a recorded area of a recording medium is read.

Therefore, such a data reproducing method reads a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium, thereby obtaining the past recorded data remaining on the recording medium. You can refer to the data.

That is, even a file deleted in the past can be recovered and used.

Further, access to a file can be restricted by using the authentication information included in the virtual allocation table.

The data reproducing apparatus according to the present invention provides a virtual allocation table showing a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data reproducing apparatus that manages a file based on the data and reproduces data, wherein the control means performs control for reading a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. Having.

Therefore, such a data reproducing apparatus can refer to data recorded in the past by reading a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium.

That is, even a file deleted in the past can be recovered and used.

Further, access to a file can be restricted by using the authentication information included in the virtual allocation table.

In the data recording method according to the present invention, a virtual allocation table indicating a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. Is a data recording method for managing files and recording data based on a virtual allocation table recorded on a recording medium, and appending it to the last end of a recorded area of the recording medium.

Therefore, according to such a data recording method, the past recording state can be restored by reading out the virtual allocation table recorded on the recording medium and continuously adding it to the last end of the recorded area of the recording medium. .

Further, when deleting a file, it is possible to save the disk space required for the deletion. Further, at this time, since the operation related to the deletion is omitted, the processing time can be reduced.

Further, by describing the authentication information in the virtual allocation table, access to the file can be restricted.

The data recording apparatus according to the present invention provides a virtual allocation table showing a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data recording device that manages a file based on the data and records the data, reads out a virtual allocation table recorded on a recording medium, and performs control for additionally writing to a final end of a recorded area of the recording medium. Control means for performing the following.

Here, the virtual allocation table to be read is the virtual allocation table recorded at the last end of the recorded area of the recording medium, and the virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. It may be a virtual allocation table.

Therefore, such a data recording apparatus can restore the past recording state by reading out the virtual allocation table recorded on the recording medium and adding it to the last end of the recorded area of the recording medium. .

Further, when deleting a file, it is possible to reduce the disk consumption capacity associated with the deletion. Further, at this time, since the operation related to the deletion is omitted, the processing time can be reduced.

Further, by describing authentication information in the virtual allocation table, access to a file can be restricted.

[Brief description of the drawings]

FIG. 1 is a diagram showing a management unit (hereinafter, referred to as a volume) structure of a removable recording medium that accommodates files and the like in a UDF-compliant file system.

FIG. 2 is a diagram schematically illustrating a file seek process in a UDF-compliant file system.

FIG. 3 is a block diagram showing a configuration of a digital still camera shown as an embodiment of the present invention.

FIG. 4 is a diagram showing a position on a recording medium of image data photographed by a digital still camera shown as an embodiment of the present invention and written on the recording medium, and a structure of the image data.

FIG. 5A is a structural diagram showing a volume structure of a UDF when a digital still camera shown as an embodiment of the present invention initializes (initializes) a recording medium. FIG. 5B is a structural diagram illustrating a volume structure of the UDF in a state where a plurality of images are captured from the initialized state and image data is additionally written in the captured order. FIG. 5 (c) reads and changes the virtual allocation volume (VAT ICB) recorded at the end of the recorded area,
FIG. 10 is a structural diagram showing a UDF volume structure when a new VAT ICB is generated and added to the current end of recording.

FIG. 6A is a structural diagram showing a volume structure of a UDF at the time of initialization (initialization). FIG.
(B) is a structural diagram showing a volume structure of a UDF in a state where a plurality of images are captured from an initialized state and image data is additionally written in the order in which the images were captured. FIG.
(C) reads out the VAT ICB immediately before the latest VAT ICB and adds the VAT ICB to the current end of the recording.
FIG. 3 is a structural diagram showing a volume structure of a DF.

FIG. 7 illustrates a digital still camera according to an embodiment of the present invention.
6 is a flowchart illustrating an operation of reading an AT ICB and additionally writing the VAT ICB to the current end of recording.

FIG. 8A is a structural diagram showing a volume structure of a UDF at the time of initialization (initialization). FIG.
(B) is a structural diagram showing a volume structure of a UDF in a state where a plurality of images are captured from an initialized state and image data is additionally written in the order in which the images were captured. FIG.
(C) is a structural diagram showing the volume structure of the UDF when the VAT ICB described at the time of initialization is read and this VAT ICB is added to the current end of recording.

FIG. 9 shows a control unit of a digital still camera according to an embodiment of the present invention, which has a VAT described at the time of initialization.
9 is a flowchart illustrating an operation of reading an ICB and additionally writing the VAT ICB to the current end of recording.

FIG. 10 is a flowchart illustrating an operation in which a control unit of the digital still camera shown as an embodiment of the present invention records authentication information in a VAT ICB.

FIG. 11 is a flowchart illustrating an operation in which the control unit of the digital still camera shown as the embodiment of the present invention reads a file whose access is restricted based on the authentication information described in the VAT ICB.

[Explanation of symbols]

Reference Signs List 1 digital still camera, 10 image pickup device, 11 image signal operation processing unit, 12 display unit, 13 OP unit, 14
RF processing unit, 15 servo signal processing unit, 16 analog filter processing unit, 17 signal processing unit, 18 spindle driver, 19 thread driver, 20 tracking driver, 21 focus driver, 22 spindle, 23 thread, 24 control unit, 30 lens unit ,
31 charge-coupled device, 32 S / H circuit, 33 A / D conversion circuit, 100 physical area, 101 physical area, 102
Volume, 103 image data, 104 image data, 105 joining recording portion, 106 joining recording portion, 1
07 joint recording part, 108 joint recording part, 109,
110, 111, 112, 113, 114, 115, 1
16, 117, 118 segments, 120, 121,
122 blocks

Claims (28)

[Claims] 1. File management based on a virtual allocation table indicating correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data reproduction method for reproducing data by performing a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. 2. The data reproducing method according to claim 1, wherein said recording medium is a disk-shaped write-once recording medium. 3. The data reproducing method according to claim 1, wherein the virtual allocation table includes authentication information, and reads out a predetermined file based on the virtual allocation table only when the authentication is confirmed. . 4. The data reproducing method according to claim 1, wherein the oldest virtual allocation table recorded on the recording medium is read. 5. An OSTA (Optical Storage Technology Ass)
2. The data reproducing method according to claim 1, wherein the file management is performed in accordance with a universal disk format defined by the association. 6. The virtual allocation table according to claim 5, wherein the virtual allocation table is a virtual allocation table in a universal disk format.
Data reproduction method described. 7. File management based on a virtual allocation table indicating correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data reproducing apparatus for reproducing data by performing a control operation for reading a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. Data reproducing device. 8. The data reproducing apparatus according to claim 7, wherein said recording medium is a disk-shaped write-once recording medium. 9. The virtual allocation table includes authentication information, and the control unit reads a predetermined file based on the virtual allocation table only when authentication is confirmed. A data reproducing apparatus according to claim 1. 10. The data reproducing apparatus according to claim 7, wherein said control means reads the oldest virtual allocation table recorded on said recording medium. 11. An optical storage device comprising: an optical storage device (OSTA);
age Technology Association)
8. The data reproducing apparatus according to claim 7, wherein the file is managed according to a disk format. 12. The data reproducing apparatus according to claim 11, wherein said virtual allocation table is a virtual allocation table in a universal disk format. 13. File management based on a virtual allocation table showing correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data recording method for recording data by performing a virtual allocation table recorded on a recording medium,
A data recording method, characterized in that additional recording is performed continuously to the last end of a recorded area of the recording medium. 14. The data recording method according to claim 13, wherein the read virtual allocation table is a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. . 15. The read virtual allocation table is a virtual allocation table recorded at the last end of a recorded area of the recording medium. The virtual allocation table is changed, and the changed virtual allocation table is replaced with the virtual allocation table. 14. The data recording method according to claim 13, wherein additional recording is performed after the virtual allocation table recorded at the last end of the recorded area of the recording medium. 16. The data recording method according to claim 13, wherein said recording medium is a disk-shaped write-once recording medium. 17. The data recording method according to claim 13, wherein authentication information for reading the virtual allocation table only when the authentication is confirmed is described in the virtual allocation table. 18. The method according to claim 13, wherein the oldest virtual allocation table recorded on the recording medium is read.
Data recording method described. 19. An OSTA (Optical Storage Technology A)
14. The data recording method according to claim 13, wherein the file is managed according to a universal disk format defined by the association. 20. The data recording method according to claim 19, wherein said virtual allocation table is a virtual allocation table in a universal disk format. 21. File management based on a virtual allocation table showing a correspondence between a real address indicating a recording position of a file storing data and a virtual address indicating a virtual recording position of the file. A data recording device that records data by performing a virtual allocation table that is recorded on a recording medium.
A data recording apparatus, comprising: a control unit for performing control for performing additional recording continuously to a final end of a recorded area of the recording medium. 22. The data recording apparatus according to claim 21, wherein the read virtual allocation table is a virtual allocation table other than the virtual allocation table recorded at the last end of the recorded area of the recording medium. . 23. The read virtual allocation table is a virtual allocation table recorded at the last end of a recorded area of the recording medium. The virtual allocation table is changed, and the changed virtual allocation table is replaced with the virtual allocation table. 22. The data recording apparatus according to claim 21, wherein additional recording is performed after the virtual allocation table recorded at the last end of the recorded area of the recording medium. 24. The data recording apparatus according to claim 21, wherein said recording medium is a disk-shaped write-once recording medium. 25. The data recording apparatus according to claim 21, wherein said control means writes authentication information in said virtual allocation table such that said virtual allocation table is read only when authentication is confirmed. 26. The data recording apparatus according to claim 21, wherein said control means reads out the oldest virtual allocation table recorded on said recording medium. 27. The control device according to claim 27, wherein the control means is an OSTA (Optical Stor
age Technology Association)
22. The data recording apparatus according to claim 21, wherein the file is managed in accordance with a disk format. 28. The data recording apparatus according to claim 27, wherein said virtual allocation table is a virtual allocation table in a universal disk format.