JP2001291367A - Optical recording medium, optical recording medium recording method, and optical recording medium reproducing method - Google Patents

Abstract

(57) [Summary] On a rewritable recording medium, a plurality of file management areas, such as a root directory, which are frequently rewritten, are secured in advance, and rewriting is performed at a different location each time. By preventing the deterioration, the deterioration of the specific area is suppressed, and the life as a recording medium is greatly extended. SOLUTION: A data area composed of a plurality of sectors to record user information (area after LBA = 5632)
And a rewritable data management information recording area (area before LBA = 5600) for recording management information composed of a plurality of elements in order to manage user information recorded in the data area. The data management information including a plurality of elements has a specific area in which a specific element is written, and the specific area has a plurality of small areas (small blocks) in which the specific element can be written.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to, for example, a CD-RW
The present invention relates to an optical recording medium, an optical recording medium recording method, and an optical recording medium reproducing method suitable for use in arranging a root directory or the like of a (CD-rewritable) disk.

[0002]

2. Description of the Related Art CD-RW disks (optical recording media) are
It is rewritable and can record computer data as well as voice and music. For example, the user can record computer data as a backup of data stored on a hard disk, or the user can record voice as teaching material for English lessons, etc. Used for

In this CD-RW disc, a guide groove (groove) for guiding a laser beam is provided on a substrate, and the guide groove is formed as a single spiral track from an inner peripheral portion of the disc. I have. Then, the entire surface of the disk including the guide groove is covered with a recording layer on which recording can be performed by the phase change recording method.
Is generated.

[0004] In this bit generation method, a laser beam is applied to a recording layer formed on a substrate so that a specific portion is irradiated with a laser beam.
The irradiated portion is made amorphous by cooling rapidly to a temperature of at least 400 ° C.
The crystalline state is maintained by heating to a degree and cooling slowly, so that two types of phases are generated. And the method of reading bits is
The bit is irradiated with laser light, and logic 1 or 0 is read depending on the difference in the reflectance of the reflected light.

Therefore, the user can repeatedly record user information by using the above-mentioned physical recording method. In this case, the logical recording format is
UDF (Universal Disc Format)
t) Recorded user information is managed by data management information based on the standard. This UDF
The UDF format based on the standard is a file system that can be used for not only one type of media but also various types of media, and various types of OS (Operation Sy
This is a file system in which compatibility between the file systems is ensured.

Specifically, according to the UDF format, 128 TB (terabytes: 10 to the power of 12)
Up to volumes are supported, Unicode (one of the character code types) is supported, and file names of up to 255 characters can be used regardless of the OS or media. . Here, the volume refers to a capacity or area that can be used by the recording / reproducing system.

The UDF format is ECMA16
7 / ISO13346 (JIS X0607-199)
Using the file system standardized in 6), US OSTA (Optical Storage Tech)
Novelty Association). The UDF format supports file attributes unique to the OS. For example, MS-DOS, W
windows3. X / 95/98 / NT, MacOS,
POSIX and OS / 2 (both are trade names) support unique file attributes in each OS. In addition, the UDF format can support other file systems on the same disk.

In the UDF format, data management information for managing recorded user information is frequently rewritten. Here, the data management information is composed of a plurality of elements, which are information on volume capacity and remaining capacity, information on history of previous access, file management information such as file name and time stamp, and time. -Refers to volume management information such as a stamp, and these elements are respectively written in a specific area in a management area (a data management information recording area described later).

That is, among the elements, the file management information includes a list of file names written in the data area,
A list of directory names, map information indicating the start and end points of a file or directory, and time and date when the date and time when the file was rewritten or read were recorded
Indicates a stamp or the like. Further, the volume management information includes information about the remaining capacity such as the size and position of the remaining area that can be rewritten by the user on the CD-RW disc, and a time stamp that records the date and time when the data area was rewritten. Represent.

[0010] The specific area is specifically a logical volume integrity descriptor area, a space
Represents a bitmap descriptor, root directory area, etc. Next, how these areas are mapped on a CD-RW disc will be described with reference to FIGS.
This will be described with reference to FIG. FIG. 10 is a diagram showing an example of an arrangement of volumes using the UDF format. This figure 1
0 (UDF Volume S)
LBA (Logical) is on the left side of the structure.
Block Address), and a descriptor name is attached to the right side. Here, the LBA is the address of the program area of the CD-RW disc, and scales from 0 to N in units of 2048 bytes. Where 2
048 bytes correspond to a sector which is a basic unit of data. N is a natural number and corresponds to the last sector address of the volume.

The descriptor is for distinguishing a plurality of pointer areas or value (value itself) areas. A pointer (predetermined LBA value) or a value to a location where the above-mentioned data management information is distributed and written is stored in the pointer area to which the descriptor is attached, and the index function is exhibited. ing. That is, the recording / reproducing system can quickly access each of the distributed and written portions. Note that the recording / reproducing system means a device having a recording laser beam for a CD-RW disc and also having a reproducing circuit for reading reflected light of the irradiated laser beam,
In the following description, the same meaning is used.

FIG. 11 is a diagram showing a coding example for realizing the pointer area, and shows the data structure of the logical volume integrity descriptor area at LBA = 352 in FIG. The structure Logica shown in FIG.
lVolumeIntegrityDesc is a data structure that implements a logical volume integrity descriptor area.
It has data contents such as scriptorTag and RecordingDateAndTime. The structure of this DescriptorTag is as shown in FIG.

FIG. 12A is a diagram showing a tag format of a volume descriptor. According to the tag identifier (Tag Identifier) shown in FIG.
Each descriptor is identified. FIG.
Descript in structure LogicalVolumeIntegrityDesc shown in
The value of orTag is 9, and each descriptor is distinguished by this value. FIG.
(B) shows an example of the value of the tag identifier.

In the following, the descriptors written in LBA = 16 to 2464 in the volume layout diagram shown in FIG. 10 will be described. The area before LBA = 2464 of the UDF volume shown in FIG. 10 includes a volume descriptor definition area (LBA = 16 to 18) and an anchor volume descriptor (Anchor Volume) of LBA = 256.
e Descriptor) area and LBA = 288-
293 Main Volume Descriptor (Main Volume Descriptor)
Descriptor area and LBA = 320-3
25 reserved volume descriptors (Reserve Vol)
UME Descriptor area and LBA = 35
2 Logical Volume Integrity Descriptor (Lo
Gical Volume Integrity De
descriptor) area and LBA = 1408-243
And two spare areas.

The LB of the volume shown in FIG.
The area after A = 2464 is a partition (Part)
) or a logical volume, and is written as a data area where a user can actually write data. First, in FIG. 10, the volume descriptor definition area (LBA = 16 to 18)
Descriptors recorded in ISO (Internatio)
nal Organization for Standardization) / IEC (In
ternational Electrotechnical Commission) 1334
6 is read when the format No. 6 is used. In addition, a Beginning / Extended area (Beginning Extended Area)
The descriptor indicates the start. For this descriptor,
This will be described with reference to FIGS.

FIG. 13A is a diagram showing a format of a volume structure descriptor. B shown in FIG.
P (Byte Position) indicates the start position of a sector of 2048 bytes, and BP = 1
The standard identifier (Standard Identifier) is written in the area (area of BP = 1) marked with. FIG. 13B shows the value of the standard identifier. For example, in the case of the value "CD001", the disc is written in the ISO9660 format used in the CD-ROM format standard. Is shown. The above-mentioned beginning extended area descriptor has a format as shown in FIG.

In FIG. 10, a terminating extended area (Terminati) of LBA = 18 is used.
The ng Extended Area) descriptor indicates the end, and the NSR descriptor between them indicates the existence of the UDF format. Subsequently, the anchor volume descriptor of LBA = 256 shown in FIG. 10 indicates that the disk handled by the recording / reproducing system uses the UDF format, and this area has a main volume descriptor area (LBA = 288). . 293) and the start position of the reserved volume descriptor (LBA = 320-325) are written.

FIG. 14A is a diagram showing the format of the anchor volume descriptor pointer. The start position of the main volume descriptor area is written in BP = 16.
= 24, the start position of the reserved volume descriptor area is written. This anchor volume descriptor is
In addition to this LBA = 256, LBA = (N-256),
LBA = (N) is provided at three places. N is the same as above.

Next, in FIG. 10, LBA = 288 Primary Volume Descriptor (Primary Volume)
Descriptor specifies a volume and indicates characteristics of the volume. The primary volume descriptor is a terminating descriptor (Termi) provided at LBA = 293 and indicating the end.
In this case, the start of the pointer area is indicated in cooperation with the N.N.ing Descriptor. FIG.
FIG. 3B shows the format of the primary volume descriptor, in which information necessary for managing the volume is written.

In FIG. 10, a Logical Volume Descriptor (Logical Volume) of LBA = 289 is used.
e Descriptor) is the number of partition areas and the logical volume integrity descriptor (L
official VolumeIntegrity De
and the number of sparing tables, the size and position of the sparing tables, and the like. This Integrity Sequence Extent Location (Integrity Sequence Ext)
The pointer called “ent Location” is always rewritten each time the recording / reproducing system rewrites.

Subsequently, a partition descriptor of LBA = 290 (Partition Descriptor)
In the area, the start position of the partition is LBA = 2464
And that the partition length is 272992, and so on. FIG. 15A shows the format of the partition descriptor area.

Further, the unallocated space descriptor (Unallocate) of LBA = 291 in FIG.
d Space Descriptor) area, the LBA value of the area for which the recording / reproducing system is prohibited from being used is written. Specifically, in FIG.
A = 32 to 255 and LBA = 384 to 1407 are set as use prohibited areas. FIG. 15 (b)
Shows the format of the unallocated space descriptor.

In FIG. 10, the implementation use volume descriptor (Im) of LBA = 292
prementation Use Volume D
In the (scriptor) area, information to be written by software for recording / reproducing a CD-RW disc is written, and more specifically, the company name and version of the software are written.

Further, the same reserved volume descriptor area (LBA = 288-293) as the reserved volume descriptor area (LBA = 320-325) with LBA = 320-325 is recorded. Next, the logical volume integrity descriptor of LBA = 352 indicates the block size, free size, the number of files, the number of directories, and the like used in each partition.

FIG. 16A shows the format of a logical volume integrity descriptor. Recording date, recording time, integrity type, next integrity type, usage status of logical volume contents, number of partitions, implementation length, free space table, size table, and area for implementation It is shown.

FIG. 16B shows the format of the implementation use area in the logical volume integrity descriptor.
Information such as the number of directories and the version that can support the UDF format is recorded. This allows
The recording / reproducing system first jumps from the logical volume descriptor area (LBA = 289) to the logical volume integrity descriptor area (LBA = 352).
The number of directories and the UDF version are read.

In FIG. 10, LBA = 1408-2
The sparing area 431 is used for defect management. That is, the area where the reading or writing could not be performed normally is to be replaced. Also, LBA =
2432 Sparing Table
ables), information for managing the sparing area is written.

As described above, a plurality of main pointers are recorded, and the address to be jumped next can be known from the value of the tag written in this area. Next, L
Each descriptor area in the partition area starting from BA = 2464 will be described. First, LBA = 2464
Space Bitmap Descriptor (Space Bit)
The map Volume Descriptor area indicates whether or not each of a plurality of sectors in the data area has been written. For example, the number of bits is recorded as 272992 and the number of bytes is recorded as 34124. FIG. 17A shows the format of the space bitmap descriptor.

The file set descriptor (File Set Descriptor) area of LBA = 2496 indicates a file and a directory to be recorded. Here, the position of the root directory is indicated. FIG. 17B is a diagram showing the format of a file set descriptor, in which a pointer indicating a location where a specific file is written is recorded.

Further, in FIG. 10, LBA = 252
The root directory 8 indicates the first file entry. FIG. 18A is a diagram showing a format of a file entry, in which a file attribute, a location where a file is written, a name of the file, a time stamp, and the like are written. FIG.
FIG. 8B shows the format of a file identifier descriptor.

As a result, the recording / reproducing system acquires the relative position 64 of the root directory recorded in the file set descriptor, and recognizes LBA = 2528, which is obtained by adding 64 to LBA = 2464, as the root directory. In the area following the root directory, data information of the user is recorded as a data area, for example, data such as audio is recorded.

With such a configuration, the flow of writing a file in the root directory and the flow of reading a file in the root directory are described in FIG.
This will be described with reference to FIG. Prior to this,
Recognition of UDF volume is performed.
It is omitted here and will be described later in detail.

FIG. 19 is a flowchart showing a method of writing a file to the root directory. First, file information is written to a file entry for the root directory (step P1). Then, information indicating that the file is in use is written in the space bitmap descriptor (step P2), and further, the information is also written in the logical volume integrity descriptor (step P3). The file is written in the area (data area) (step P4).

FIG. 20 is a flowchart showing a method of reading a file in the root directory. First, the file information of the file entry for the root directory is read (step P101), and the file is read (step P102). ). As described above, the file management information (file name, time stamp, etc.) and the volume management information (volume capacity, remaining capacity, time stamp, etc.)
Recorded in the partition area of the CD-RW disc,
These pieces of information are stored in the primary volume descriptor area (LBA = 2
88 to 293).

[0035]

However, since the above-mentioned UDF format is created mainly for a read-only recording medium, the specific area is rewritten many times and the physical characteristics of the disc deteriorate. Is not taken into account. That is, the file management areas such as the logical volume integrity descriptor area, the space bitmap descriptor area, and the root directory are:
These parts are deteriorated because they are frequently rewritten.
Bit recording and reproduction cannot be performed. In particular, the two blocks, the head part of the root directory and the remaining capacity recording part, are each rewritten many times and deteriorate quickly.

The main cause of this deterioration is that if the formation of bits in the same portion is repeated,
When the phase change type recording layer is melted, the melted portion flows or the portion becomes a hole, so that the difference of 1 or 0 cannot be obtained as the reflectance. . The number of rewritable times of this phase change type optical recording medium is specifically about 1000 times, and the MO (Mag)
neto-optical) from 100,000 times to 10
It is less than 100,000 times. Therefore, when the user rewrites about 1000 times, there is a problem that the data area cannot be used as a recording medium due to deterioration of the root directory even though the data area can still be sufficiently used.

Therefore, even if the location of the root directory is changed by changing the location of the root directory or shifting the pointer value, the changed location is frequently rewritten. cause. The present invention has been made in view of such a problem, and in a rewritable recording medium, a plurality of file management areas, such as a root directory, which are frequently rewritten, are secured in advance, and rewriting is performed in different places each time. An optical recording medium and an optical recording medium recording method that can prevent frequent rewriting in a specific area, thereby suppressing deterioration of the specific area and greatly extending the life as a recording medium And an optical recording medium reproducing method.

[0038]

For this reason, the first aspect of the present invention is described.
The gist of the present invention includes a data area composed of a plurality of sectors for recording user information, and a rewritable management area for recording data management information composed of a plurality of elements for managing user information recorded in the data area. The management area has a specific area for writing a specific element of the data management information including a plurality of elements, and the specific area has a plurality of small areas each of which can write a specific element.

According to a second aspect of the present invention, in the optical recording medium according to the first aspect, the management area includes at least an element relating to the number of files and the number of directories as a specific element, and a logical volume and a logical volume as the specific area. In order to write in the integrity descriptor area, a configuration is adopted in which the logical volume integrity descriptor area has a plurality of small areas in which specific elements can be written.

Further, a third gist of the present invention resides in the first aspect.
In the optical recording medium according to the gist of the present invention, the management area is used as a specific element to write at least an element relating to the presence or absence of writing for each of the plurality of sectors in the data area into the space bitmap descriptor area as the specific area. A configuration in which the bitmap descriptor area has a plurality of small areas in which specific elements can be written is adopted.

The fourth gist of the present invention relates to the first aspect.
In the optical recording medium according to the gist, the data area includes a specific area for writing a specific element of the data management information including a plurality of elements, and the specific element is an element relating to a file entry which is at least a head address of a file to be recorded. Is written in a root directory area as a specific area, the root directory area has a configuration having a plurality of small areas in which specific elements can be written.

According to a fifth aspect of the present invention, in the optical recording medium according to the first aspect, the data area and the management area are each recorded by a phase change recording method. In addition, according to a sixth aspect of the present invention, in the optical recording medium according to the fifth aspect, the management area is provided so as to avoid deterioration of a reproduction signal due to repeated recording of bits.
A configuration is adopted in which the capacity of the rewritable area or the number of the plurality of small areas is set to a desired value.

Further, a seventh gist of the present invention is the above-mentioned sixth aspect.
In the optical recording medium according to the gist of the invention, a configuration is adopted in which the capacity of the rewritable area of the management area is set to a predetermined ratio of the total recording capacity of the data area. An eighth aspect of the present invention provides the optical recording medium according to the fifth aspect,
A configuration is adopted in which the management element writes the specific element in a small area of the plurality of small areas in which the reproduction signal does not deteriorate due to repeated recording of bits.

A ninth aspect of the present invention employs a configuration in which, in the optical recording medium according to the first aspect, a sequence number is written in each of a plurality of small areas. Further, a tenth aspect of the present invention employs a configuration in which the optical recording medium according to the first aspect is a recording medium for writing data for a database. And the eleventh of the present invention
The gist of the present invention is to provide a data area in which user information can be recorded and a rewritable management area for recording data management information composed of a plurality of elements for managing the user information recorded in the data area. An optical recording medium recording method for an optical recording medium having a specific area for writing a specific element of the data management information composed of In writing a specific element in a small area of a plurality of small areas included in the method, a method of writing a specific element in a small area different from the previously written small area is adopted.

In a twelfth aspect of the present invention, in the optical recording medium recording method according to the eleventh aspect, a method of writing a specific element in a small area having the least writing frequency among a plurality of small areas is adopted. I do. According to a thirteenth aspect of the present invention, there is provided the optical recording medium recording method according to the eleventh aspect, wherein the specific element is written in a small area, which is separated from the previously written small area by a predetermined address, among the plurality of small areas. Adopt the method.

Further, according to a fourteenth aspect of the present invention, in the optical recording medium recording method according to the eleventh aspect, a method is employed in which at least a specific element written in the previous writing is not erased. A fifteenth aspect of the present invention provides a data area in which user information can be recorded, and a rewritable management area for recording data management information including a plurality of elements to manage user information recorded in the data area. An optical recording medium reproducing method for an optical recording medium having a specific area in which a specific area of a data management information including a plurality of elements and a specific area to which a specific element can be written, wherein the specific area has a plurality of small areas into which a specific element can be written In reading out a specific element written in one small area of a plurality of small areas of the specific area, a specific element is read from the last written small area.

[0047]

Embodiments of the present invention will be described below with reference to the drawings. (A) Description of an embodiment of the present invention FIG. 1 is a diagram showing an arrangement of program areas of a CD-RW disc 10 to which the present invention is applied. C shown in FIG.
The program area (also referred to as a program area) of the D-RW disc 10 is an area for a user to actually write user information. Here, writing by a user means that an individual user records user information such as computer data in addition to voice and music, and a corporate user related to electronic publishing sells user information such as computer data in advance as a product. The same meaning is used in the following description.

Then, the CD-RW disc 1 shown in FIG.
The program area starts 25 mm (r25) away from the center of zero. The physical structure of the program area is a guide groove for guiding a laser beam for irradiating the CD-RW disc 10.
Are formed as a single spiral track (not shown) from the inner peripheral portion. Further, this program area has a data area and a data management information recording area (management area), and ends at a distance of 58 mm (r58) from the center of the CD-RW disc 10.

FIG. 2 is a layout diagram of volumes using the UDF format according to an embodiment of the present invention. The volume layout diagram (UDF Volume S) shown in FIG.
Structure) is a mapping of the program area shown in FIG. 1. The program area includes a data area (area after LBA = 5632) and a data management information recording area (mainly an area before LBA = 5600).
And each of them. Here, the data management information is
It is composed of a plurality of elements, and the elements refer to the above-described file management information and volume management information, and these plurality of elements are respectively written in a specific area in the data management information recording area.

In the data area and the data management information recording area, for example, recording and reproduction are respectively performed by a phase change recording method. Accordingly, the CD-RW disk (optical recording medium) 10 includes a data area and a data management information recording area, and the data area is composed of a plurality of sectors for recording user information. The information recording area is a rewritable area for recording data management information including a plurality of elements in order to manage user information recorded in the data area. The data management information recording area includes a specific area for writing a specific element of the data management information composed of a plurality of elements. For example, 100 specific small blocks (small area ). Each of the small blocks includes one packet (normally, 32 sectors = 64 kilobytes).

Here, the data management information recording area is a logical volume integrity descriptor area (LBA =
352-3551) and a space bitmap descriptor area (LBA = 5632-8831), and
The data area is a root directory area (LBA = 88
64 to 12063). Each of these three areas is provided with, for example, 100 small blocks.

The number of the small blocks is not limited to 100, but can be set to various values so as to avoid the discrimination of the reflectance caused when the bit formation is repeated. Compared with the ordinary UDF format, in the ordinary UDF format, one specific area is provided with only one small block, whereas in the UDF format according to the present invention, one specific area has, for example, 100 Small blocks are provided.

In the volume layout diagram shown in FIG. 2, the data management information recording area includes, as specific elements, elements relating to the number of files and directories, and a logical volume integrity descriptor area (LBA = 352-3551)
This logical volume integrity descriptor area has, for example, a plurality of small blocks of 100 in which a specific element can be written.

The data management information recording area is
As the specific element, an element relating to the presence or absence of writing for each of the plurality of sectors in the data area is described as a space bitmap descriptor area (LB) as the specific area.
A = 5632 to 8831), this space bitmap descriptor area has, for example, a plurality of small blocks of 100 to which a specific element can be written.

Further, the data management information recording area has a specific area for writing a specific element of the data management information composed of a plurality of elements, and relates to a file entry which is a head address of a file to be recorded as a specific element. In order to write an element into a root directory area (LBA = 8864 to 12063) as a specific area, this root directory area has, for example, a plurality of 100 small blocks in which a specific element can be written.

Next, the details of the data management information recording area will be described with reference to FIGS. In the present invention, preferably, a sequence number is written in each small block, and each time a write is performed in each small block,
The sequence number of the small block is rewritten, for example, by incrementing by one.

Thus, it is easy to specify in which of the small blocks the latest specific information is written, and it is easy to specify the position of the small block to be read and the position of the next small block to be written. In consideration of compatibility with the conventional format, it is preferable that the position of the small block accessed first by the recording / reproducing apparatus is always the same. The recording / reproducing apparatus reads out the sequence number of the small block accessed first, sequentially scans the sequence numbers of adjacent small blocks, and detects the largest number to find the last written small block. It is. More preferably, two types of sequence numbers are assigned in consideration of superimposability and the like.

FIG. 3 is a diagram showing a format of a logical volume integrity according to an embodiment of the present invention. In addition to a normal format part, a sequence number (Sequence Number) area and a next sequence number (Next Sequence Number) are shown.
r) region is provided. That is, a sequence number is written in each of the plurality of small blocks 20a as shown in FIG. Then, the next specific element is written in the specific small block 20a having the current sequence number and the next sequence number, and in which the next sequence number of the certain small block 20a is equal to the current sequence number.

For example, when the logical volume integrity descriptor area is composed of 100 small blocks 20a and is not used, the sequence numbers and the next sequence numbers of all these small blocks 20a are 0, respectively.
Is set to Then, by the first access, the sequence number of the accessed specific small block 20a is set to 1 as an initial value, and the next sequence number is set to 2. Further, by the second access, the sequence number is set to 2 and the next sequence number is set to 3. Similarly, the sequence number and the next sequence number are set in order.

As a result, the recording / reproducing system becomes 100
Search for these sequence numbers and the next sequence numbers of the small blocks 20a, and among these,
When both sequence numbers are the maximum, the small block 20a is recognized as the small block 20a to be read. FIG. 4 shows a space according to an embodiment of the present invention.
FIG. 5 is a diagram showing a format of a bitmap descriptor, and FIG. 5 is a diagram showing a format of a file entry according to an embodiment of the present invention. As shown in FIGS. 4 and 5, respectively, similar to the format of the logical volume integrity, the small block 20a has a current sequence number and a next sequence number, and the next sequence number is equal to the current sequence number. If not, it is recognized as the latest small block 20a to be written.

Accordingly, the recording / reproducing system is, for example, 10
Of the 0 small blocks 20a, the latest small block 20
a can be recognized without error. Next, a writing (recording) method and a reading (reproduction) method will be described with reference to FIG. FIG. 6 is a diagram for explaining a method of writing / reading a plurality of small blocks 20a in a root directory area according to an embodiment of the present invention. The root directory 20 shown in FIG. 6 has n small blocks 20a, and each small block 20a is composed of one packet (32 sectors = 64 kilobytes). Here, n is an integer of 1 or more, for example, 100. The small block 20a has a dark pattern. Note that the number of small blocks 20a is not limited to 100, and is set to various values according to a change in the design policy.

The pointer of the root directory 20 is first written into the first small block 20a, and when the pointer is accessed next, the next small block 20a is written.
, And thereafter, every time the access is made, the position where the pointer is written is shifted one by one. Further, after writing up to the n-th small block 20a, the (n + 1) -th writing is performed again on the first small block 20a, and thereafter, each time the pointer is accessed, the position where the pointer is written is shifted by one. The 2n-th write is performed on the last n-th small block 20a. In the same manner, the subsequent writing is repeatedly performed in order on the first small block 20a to the n-th small block 20a.

By setting the total recording capacity and the number of small blocks 20a in these three data management information recording areas to be large, respectively, the number of times a specific part is accessed is reduced, and the life of the disk is extended. However, in order to use the limited capacity efficiently, the capacity must be reduced to a predetermined capacity. That is, in the data management information recording area, the total recording capacity or the number of the plurality of small blocks 20a is set to a desired value in order to avoid deterioration of the reproduction signal due to repeated recording of bits.

For this reason, the capacity of the rewritable area of the data management information recording area is equal to 0 .0 of the total recording capacity of the data area.
It is desirable to provide so that it may be set to 35%-3.5%. Further, regarding the number of small blocks 20a, the data management information recording area has two small blocks 20a.
It is desirable to provide about 1 to 100 pieces. Therefore, if the writing life of one small block 20a is, for example, 1000 times, by providing 100 small blocks 20a, the writing life can be extended to 100,000 times by simple calculation.

As described above, the latest small block 20a is updated every time the recording / reproducing system accesses, so that it is avoided that only one small block 20a is intensively rewritten. Therefore, for example, the deterioration of the root directory 20 is remarkably improved, and the life of the CD-RW disk 10 is greatly extended. Furthermore, in this way, the purchase of the CD-RW disc 10 as an optical recording medium is promoted, and the user's usability is enhanced compared to other recording media, in combination with the compatibility of the CD.

In the optical recording medium recording method of the present invention, a data area in which user information can be recorded, and a rewritable data recording medium for recording data management information including a plurality of elements for managing the user information recorded in the data area. The data management information recording area includes a specific area for writing a specific element of the data management information including a plurality of elements, and the specific area includes a plurality of small blocks 20a each capable of writing a specific element. CD-RW with
This is an optical recording medium recording method for the disk 10. Then, when writing the specific element to the small block 20a of the plurality of small blocks 20a included in the specific area, the small block 2 different from the previously written small block 20a
The specific element is written to 0a.

In this writing, the old specific element left in each of the other small blocks 20a is not erased, and the old data management area left by the previous writing is not written in the data management information recording area. Information is not erased. Therefore, the old data management information can be held as a kind of backup data. In particular, it is preferable to keep the management information immediately before the current management information.

Further, in this writing, the specific element is written in the small block 20a which is least frequently written out of the plurality of small blocks 20a, and the data management information is written in the small block 20a which is less frequently used. It is written. That is, every time the recording / reproducing system accesses any one of these small blocks 20a, the position of the small block 20a in the root directory 20 to be accessed next is shifted.

On the other hand, according to the optical recording medium reproducing method of the present invention, when reading out a specific element written in one small block 20a of a plurality of small blocks 20a included in a specific area, first, from the small block 20a written last. The specific element is read. Therefore, the small blocks 20a to be read are shifted in order every time. As a result, the pointer of the root directory 20 is not fixedly written at one address, but the addresses to be written are made variable and the addresses to be read are in order. It is possible to avoid rewriting and deterioration.

And, with this configuration, the UDF
The format is recognized, a file is written to the root directory 20, and a file is read from the root directory 20. The operation of these will be described with reference to FIGS. FIG. 7 is a flowchart of the UDF format recognition according to an embodiment of the present invention. First, the recording / reproducing system uses LBA = 25 in FIG.
6 or LBA = (N-256) and LBA = (N), if an anchor volume descriptor exists, read it (step A1), read the main volume descriptor (step A2), and file set descriptor Is read (step A3). Then, the recording / reproducing system reads the file entry information for the root directory (step A4) and accesses each file (step A5).

FIG. 8 is a flowchart showing a method for writing a file to a root directory according to an embodiment of the present invention. First, the recording / reproducing system searches the root directory area for file entry information for the least frequently used root directory (step B).
1). In other words, the recording / reproducing system includes: file management information including a list of file names, a list of directory names, and map information; information on a remaining capacity of a medium;
In order to record data management information having history information relating to file access and data management information having a plurality of small blocks 20a, an optical recording medium is accessed.

Then, the recording / reproducing system writes file information to the found file entry for the root directory (step B2), and uses the most frequently used information in the space bitmap descriptor area (space bitmap identifier area). Then, a space bitmap descriptor with less data is searched for (step B3), and information indicating that the file has been used is written in the space bitmap descriptor (step B4). In other words, the recording / reproducing system determines, for the small block 20a accessed in the data management information access step, the small block 20a which is least frequently used among the previously written small blocks 20a.
The data management information is written into a.

Further, the recording / reproducing system searches for the smallest Logical Volume Integrity Descriptor in the Logical Volume Integrity Descriptor area (Step B5), and writes information into this Logical Volume Integrity Descriptor (Step B6). ), And write the file (step B7). Subsequently, the recording / reproducing system repeatedly writes the data management information to each of the plurality of small blocks 20a written in the writing step.

FIG. 9 is a flowchart showing a method for reading a file into the root directory 20 according to one embodiment of the present invention. First, the recording / reproducing system searches the root directory area for file entry information for the least frequently used root directory (step C1). Then, the recording / reproducing system reads the file information of the found file entry for the root directory (step C2), and then reads the file (step C3).

The method of writing information in the logical volume integrity descriptor area is the same as the method described with reference to the flowchart of FIG. 8, and the method of reading information from the logical volume integrity descriptor area is shown in FIG. Is the same as the method described using the flowchart of FIG. Therefore, redundant description of writing and reading with respect to the logical volume integrity descriptor area will be omitted.

In addition, the method of writing information in the space bitmap descriptor area is the same as the method shown in the flowchart of FIG. 8, and the method of reading information from the space bitmap descriptor area is also shown in FIG. Since the method is the same as that of the method, a duplicate description of writing and reading with respect to the space bitmap descriptor area is omitted.

As described above, when the writing life of one small block 20a is set to, for example, 1000 times, by providing 100 small blocks 20a, the writing life can be extended to 100,000 times by simple calculation. be able to. For example, the pointer of the root directory 20 is not fixedly written at one address, but the address to be written is variable, so that deterioration due to frequent rewriting to a specific address can be avoided.

Also, as described above, the root directory 2
The location where the pointer of 0 is written is dispersed, and the influence of the degradation is dispersed.
Recognition failure due to deterioration of the 0 file entry is eliminated, and operation stability is improved. Furthermore, like this, C
Since the number of times of recording on the D-RW disc 10 is greatly increased and the added value is increased, the convenience as a general-purpose recording medium is extremely increased.

In this way, in combination with the compatibility of the CD, the usability of the user is enhanced as compared with other recording media. (B) Others The present invention is not limited to the embodiments described above,
Various modifications can be made without departing from the spirit of the present invention.

For example, the volume arrangement of the UDF format shown in FIG. 2 is not limited to this arrangement, and is designed and implemented within a range conforming to the standard based on various design policies. Root directory 2 above
The order of writing to 0 or the like can be shifted not only one by one but also in another two modes.

In the first mode, for example, writing is performed with one skip or two skips. That is, since the information of 1 and 0 is recorded by bits, one or two small blocks 20a are formed after the bits are formed in the first small block 20a so as not to be affected by heat at the time of bit formation.
You can also skip and write. That is, in the above-mentioned repetition step, a plurality of small blocks 20
The specific element may be written in the small block 20a separated from the previously written small block 20a by a predetermined address.

Further, in the second mode, the first one of the small blocks 20a in FIG. 6 is rewritten until the number of useful times at which deterioration occurs is reached, and when the number of useful times is reached, the second small block 20a is rewritten. Is to be rewritten. That is, in the data management information recording area, the specific element can be written in the small block 20a of the plurality of small blocks 20a in which the reproduction signal does not deteriorate due to the repeated recording of bits.

In addition, the ratio of the data management information recording area to the total recording capacity and the number of small blocks 20a are not limited to the values and numbers indicating the above ratios, respectively.
Depending on the design policy, the size may be set to an appropriate size. Even in this case, the superiority of the present invention is impaired at all for an invention implemented by changing the value indicating the ratio and the number. Not something.

Further, the CD-RW disc 10 of the present invention
Is desirably a recording medium for writing data for a database. That is, the basic data group for constructing the database includes the CD-RW disk 10
When the data is written in the data area, the above-mentioned data management information recording area is accessed and the data is written in a large number of locations in the data area.

The present invention can be widely applied to a phase-change type optical recording medium other than the CD-RW, and a recording medium of another system in which deterioration due to rewriting is a problem. In this case, the recording medium may not only identify the bits based on the difference in reflectance but also identify the bits based on a change in another reproduction signal.

[0086]

As described above in detail, according to the optical recording medium of the present invention, a data area composed of a plurality of sectors for recording user information and a plurality of data areas for managing user information recorded in the data area are provided. A rewritable management area for recording data management information composed of the elements of the above, the management area has a specific area for writing a specific element of the data management information composed of a plurality of elements, and the specific area has a specific element for each. Since there are a plurality of writable small areas, there is an advantage that deterioration due to frequent rewriting to only a specific address is avoided (claim 1).

In the above-mentioned optical recording medium, the logical volume integrity descriptor area of the management area has a plurality of small areas in which specific elements can be written,
Even if the space bitmap descriptor area of the management area has a plurality of small areas where a specific element can be written, or the root directory area of the data area has a plurality of small areas where a specific element can be written. In this case, practically, recognition failure due to deterioration of the file entry in the root directory is eliminated, and the operation stability is advantageously improved (claims 2 to 10).

Further, according to the optical recording medium recording method of the present invention, a data area in which user information can be recorded and data management information including a plurality of elements for managing the user information recorded in the data area are recorded. In an optical recording medium having a rewritable management area, the management area has a specific area for writing a specific element of the data management information composed of a plurality of elements, and the specific area has a plurality of small areas each of which can write a specific element. In the optical recording medium recording method, when writing a specific element in a small area of a plurality of small areas of a specific area, the specific element is written in a small area different from the previously written small area. The number of times of recording is greatly increased, the added value is increased, and the convenience as a general-purpose recording medium is extremely increased (claim 11).

The specific element may be written in a small area of the plurality of small areas where writing is least frequently performed. The specific element may be written in the small area, and in this case, the deterioration of the management area in the optical recording medium is remarkably improved, and the CD-RW
There is an advantage that the life of the disk is greatly extended.
2, Claim 13).

Further, at least the specific element written in the previous writing may not be erased, and the old specific element left in each of the plurality of small areas may not be erased. For example, since the previous management information is retained, for example, even if the current management information cannot be read due to deterioration or destruction, it can be used as backup data, so that the reliability of the optical recording medium is greatly increased. (Claim 14).

In addition, according to the optical recording medium reproducing method of the present invention, a data area in which user information can be recorded and data management information including a plurality of elements for managing the user information recorded in the data area are recorded. An optical recording medium having a rewritable management area, a management area including a specific area for writing a specific element of data management information including a plurality of elements, and a specific area including a plurality of small areas each capable of writing a specific element. In the optical recording medium reproducing method according to the above, when reading the specific element written in one small area of the plurality of small areas included in the specific area, the specific element is read from the last written small area. For example, the purchase of a CD-RW disc can be promoted, and C
Combined with the compatibility of D, compared to other recording media,
There is an advantage that the usability of the user is enhanced.
5).

[Brief description of the drawings]

FIG. 1 is a diagram showing an arrangement of a program area of a CD-RW disc to which the present invention is applied.

FIG. 2 is a layout diagram of volumes using a UDF format according to an embodiment of the present invention.

FIG. 3 is a diagram showing a format of a logical volume integrity according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a format of a space bitmap descriptor according to an embodiment of the present invention.

FIG. 5 is a diagram showing a format of a file entry according to an embodiment of the present invention.

FIG. 6 is a diagram for explaining a method of writing / reading a plurality of small blocks in a root directory area according to an embodiment of the present invention.

FIG. 7 is a UDF format recognition flowchart according to an embodiment of the present invention.

FIG. 8 is a flowchart illustrating a method for writing a file to a root directory according to an embodiment of the present invention.

FIG. 9 is a flowchart illustrating a method of reading a file into a root directory according to an embodiment of the present invention.

FIG. 10 is a diagram illustrating an example of an arrangement of volumes using a UDF format.

FIG. 11 is a diagram illustrating a coding example for realizing a pointer area.

12A is a diagram illustrating a tag format of a volume descriptor, and FIG. 12B is a diagram illustrating an example of a tag identifier value;

13A is a diagram showing a format of a volume structure descriptor, FIG. 13B is a diagram showing a value of the standard identifier, and FIG. 13C is a diagram showing a format of a beginning extended area descriptor. FIG.

14A is a diagram showing a format of an anchor volume descriptor pointer, and FIG. 14B is a diagram showing a format of a primary volume descriptor.

FIG. 15A is a diagram showing a format of the partition descriptor, and FIG. 15B is a diagram showing the format of an unallocated partition descriptor.
It is a figure showing the format of a space descriptor.

FIG. 16A is a diagram showing a format of a logical volume integrity, and FIG. 16B is a diagram showing a format of an implementation use area in a logical volume integrity descriptor.

17A is a diagram illustrating a format of a space bitmap descriptor, and FIG. 17B is a diagram illustrating a format of a file set descriptor.

FIG. 18A is a diagram showing a format of a file entry, and FIG. 18B is a diagram showing a format of a file identifier descriptor.

FIG. 19 is a flowchart illustrating a method of writing a file to a root directory.

FIG. 20 is a flowchart illustrating a method of reading a file in a root directory.

[Explanation of symbols]

 10 CD-RW disk 20 Root directory 20a Small block

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 5B082 EA01 JA12 5D044 BC06 CC04 DE03 DE12 DE23 DE25 DE38 DE54 DE58 5D090 AA01 BB04 CC14 DD03 DD05 GG11 GG17 GG28 GG33 GG36 5D110 AA17 DA01 DA06 DA12 DB13 DB17 DC16 DE04

Claims (15)

[Claims] 1. A data area comprising a plurality of sectors for recording user information, and a rewritable management area for recording data management information comprising a plurality of elements for managing the user information recorded in the data area. Wherein the management area has a specific area for writing a specific element of the data management information composed of the plurality of elements, and the specific area has a plurality of small areas each capable of writing the specific element. An optical recording medium. 2. The logical volume integrity descriptor area according to claim 2, wherein the management area writes at least an element relating to the number of files and the number of directories to the logical volume integrity descriptor area as the specific area. ,
2. The optical recording medium according to claim 1, comprising a plurality of small areas in which the specific element can be written. 3. The management area may be configured to write, as the specific element, at least an element regarding whether or not each of the plurality of sectors in the data area is written into a space bitmap descriptor area as the specific area. Wherein the space bitmap descriptor area has a plurality of small areas in which the specific element can be written.
The optical recording medium according to claim 1. 4. The data area has a specific area for writing a specific element of the data management information composed of the plurality of elements, and the specific element is an element relating to a file entry which is at least a start address of a file to be recorded. To
2. The optical recording medium according to claim 1, wherein the root directory area has a plurality of small areas in which the specific element can be written so as to write in the root directory area as the specific area. 5. The optical recording medium according to claim 1, wherein recording is performed in each of the data area and the management area by a phase change recording method. 6. The management area is characterized in that the capacity of the rewritable area or the number of the plurality of small areas is set to a desired value in order to avoid deterioration of a reproduction signal due to repeated recording of bits. The optical recording medium according to claim 5. 7. The optical recording medium according to claim 6, wherein the capacity of the rewritable area of the management area is set to be a predetermined ratio of the total recording capacity of the data area. 8. The management area according to claim 5, wherein the specific element is written in a small area of the plurality of small areas in which a reproduction signal is not deteriorated due to repeated recording of bits. Optical recording medium. 9. The optical recording medium according to claim 1, wherein a sequence number is written in each of the plurality of small areas. 10. The optical recording medium according to claim 1, wherein the optical recording medium is configured as a recording medium for writing data for a database. 11. A data area which can record user information, and a rewritable management area which records data management information including a plurality of elements for managing the user information recorded in the data area. An optical recording medium recording method in an optical recording medium, wherein a management area has a specific area for writing a specific element of the data management information composed of the plurality of elements, and the specific area has a plurality of small areas each capable of writing the specific element In writing a specific element in a small area of the plurality of small areas that the specific area has, writing the specific element in a small area different from the previously written small area,
Optical recording medium recording method. 12. The optical recording medium recording method according to claim 11, wherein said specific element is written in a small area of said plurality of small areas which is least frequently written. 13. The method according to claim 11, wherein the specific element is written in a small area of the plurality of small areas that is separated from the previously written small area by a predetermined address. Optical recording medium recording method. 14. The optical recording medium recording method according to claim 11, wherein at least the specific element written in the previous writing is not erased. 15. A data area capable of recording user information, and a rewritable management area for recording data management information including a plurality of elements for managing the user information recorded in the data area. An optical recording medium reproducing method in an optical recording medium, wherein a management area has a specific area for writing a specific element of the data management information composed of the plurality of elements, and the specific area has a plurality of small areas each capable of writing the specific element An optical recording method comprising: reading out a specific element written in a small area of the plurality of small areas included in the specific area, reading the specific element from the last written small area. Media playback method.