JPH04182981A - Optical recording medium - Google Patents

Abstract

PURPOSE:To retrieve a large quantity of data at a high speed and to efficiently execute the administration of data by forming a directory section into a hierarchy directory structure. CONSTITUTION:The directory section is constituted of the hierarchic wood structure by prescribed rules. For example, the directory section consists of three hierarchies and the respective directories (71 to 74) constituting the uppermost layer directory 75 consists of respectively the ensuing layer directories (80, 89,...). The 1st directory 7 consists of the ensuing layer directory 80 and the 2nd directory 72 consists of the ensuing layer directory 80. Further, the 2nd-2 directory 82 which is one of the sectors of the ensuing layer directory 89 consists of the lower layer directory 90 and this lower layer directory 90 includes n-pieces of files (85 to 88). The data can be accessed by the information of these files. A large quantity of the data are retrieved at a high speed in this way and the data administration is efficiently executed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical recording medium consisting of a data section and a directory section, and particularly relates to an optical recording medium in which the directory section is structured in a hierarchical tree structure. .

[Prior Art] Conventionally, information recording media include floppy disks and hard disks that perform recording and reproduction using magnetism, and optical disks and optical cards that perform recording and reproduction using light. Such recording media can store large amounts of data. A directory section is provided to efficiently manage this data. This directory section is provided to manage data to be recorded in units of blocks (files). What is recorded in the directory section are the name of each block, the contents, the position of the data block, the length of the data, etc. When reading data, it is common practice to search the directory section for directory information of the target data, and to access the data itself using the directory information obtained by the search. Particularly in large-capacity write-once information recording media such as optical discs and optical cards, it is desirable to be able to search for information quickly and easily based on the date of recording, file type, etc.

As an example of directory formation, Japanese Patent Application Laid-Open No. 63-8798
Publication No. 0 is mentioned. In this publication, the information recording medium is divided into a data section and a directory section. In addition to the file name, file length, and first track number, information regarding error correction is also recorded as directory information in this directory section.

In order to access this directory information, it is first necessary to sequentially read the directory information until the desired file name is found. If the desired file name exists at the beginning of the directory section, it can be accessed in a short time.

However, if the target file name exists near the end of the directory section, almost all of the directory information needs to be read. In this case, access takes time. In particular, optical recording media such as optical discs and optical cards can additionally record a large amount of data, and the number of files on this optical recording medium is considerable. Therefore, in the case of this conventional example, it is not possible to efficiently search for files at the end of a directory section or search for the last track.

Another conventional example is JP-A-63-48659. This conventional example does not have a directory part,
By searching the data recording area in binary,
The final record track is getting to know. In order to improve recording efficiency, this method does not create buoy reflex information during recording.

When searching for data, the data section of the entire recording surface of the medium is directly searched for the last recorded token by binary search. When additional recording is performed, recording starts from the last recorded L-rack.

When searching for this final recording track, the data reading head moves and searches the entire data section, which is much wider than the directory section. Therefore, even using binary search requires considerable access time. For example, on an optical card with 2000 tracks, a maximum of 11 (200
0=2'') track access is required. This is not an efficient access. Also, in a configuration that does not have a directory section like this, it is impossible to search by file name, type, etc. .

It is also conceivable to combine the two conventional examples described above to search only the directory section by binary search. However, with this method, the access area becomes narrower and the number of accesses is limited to only a few times, so there is no great effect. Furthermore, even with this method, it is not possible to search by file name or file content.

[Problems to be Solved by the Invention] In the conventional example, when the amount of recorded data increases in a large-capacity storage medium, especially an optical recording medium such as an optical disk or an optical card, it becomes difficult to search for a file or search for the last recorded track. Problems arose in that it took time and required complicated access.

The present invention has been made in view of these circumstances, and provides an optical recording medium with a data section and a directory section (J).
An object of the present invention is to provide an optical recording medium that can search a large amount of data at high speed and efficiently manage data.

[Means for Solving the Problems] An optical recording medium comprising: a data section for recording data; and a directory section capable of recording n sectors of directory information for managing this data in one track; rules for recording or retrieving information, the directory section is formed into a hierarchical tree structure according to the rules, and the directory information is recorded in the builf redirection section or searched for based on the rules; By searching from the I/R section, a large amount of data can be searched at high speed and data can be managed efficiently.

[Operation] As described above, the directory section is composed of a hierarchical wooden structure. Therefore, when searching for directory information, by searching in the order of major classification, middle classification, and small classification, the search can be performed quickly even with a large amount of data, and the data can be managed efficiently.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

1 to 7 relate to embodiments of the present invention, and FIG.
Fig. 1(b) is an explanatory diagram showing the relationship between directories in each hierarchy, Fig. 2 is a block diagram showing the configuration of the data management system, and Fig. 3 is a schematic diagram of the optical power card. (a) is a track configuration diagram showing the track configuration, Figure 4 is an explanatory diagram showing an example of the directory format, Figure 5 is a flowchart when recording data on an optical disc, and Figure 6 is a diagram showing how files are recorded. It is a flowchart when searching for a track.

The optical card 7 shown in FIG. 2 as an optical recording medium is a large capacity recording medium. This optical card 7 has a feeding mechanism 8
is fixed on top. This feeding mechanism 8 reciprocates the optical card 7 in the track direction in order to read and write data on the optical card. This reciprocating motion is controlled by the feed mechanism control section 9.

Reading and writing data on the optical card 7 is performed using laser light emitted from the pickup 1.

The pickup control section 2 controls the pickup 1. Specifically, when the optical card 7 moves in the track direction, tracking and focusing of the laser beam is controlled. It also controls a seek operation that moves the pickup 1 in a direction perpendicular to the track. This seek operation is
It allows reading and writing from different tracks.

The communication control unit 4 is connected to a host computer and a read/write control unit 3 (hereinafter referred to as the R/W control unit). Commands sent from the six host computers are sent via the communication control unit 4 to the R/W control unit 4. /W Sent to control section 3.

The R/W control section 3 is connected to a pickup control section 2, a feed mechanism control section 9, a directory recording section 5, and a directory search section 6 in addition to the communication control section 4 described above. The R/W control section 3 controls the pickup control section 2 and the feed mechanism control section 9. Besides that,
It also performs mutual conversion between data and binary signals, error correction, and addition of correction data. In other words, it performs comprehensive control of data read or write processing.

The directory control unit 5 creates a directory.

This directory has a tree structure in which one hierarchy is divided into n parts. Here, n is an integer value such as 8.16, and is determined by the track size and directory size. Further, the directory search unit 6 searches for files in a directory and searches for the last recording track.

FIG. 1(a) shows the configuration of an optical card.

The optical card 20 has a recording medium 21. This recording medium 21 consists of a directory section 23 and a data section 24. Further, the recording medium 21 has a plurality of tracks 2.
It has a data recording area called 2.

The structure of the track 22 is shown in FIG. A data recording area 32 is formed between the two tracking lines 31. This data recording area 32 is provided with a hole called a bit 33 . This bit 33 is formed by laser light during recording. Laser light is also used to read data.

The laser beam passes over the data recording area 32, and the reflected light is received by the light receiving element. The output signal of this light receiving element is
The difference between the bit (low reflectance) and non-bit (high reflectance) reflected light is converted into a 1.0 binary signal.

FIG. 1(b) shows an example of a hierarchical directory.

In this figure, the directory section consists of three hierarchies. Each directory (71 to 74) constituting the top layer directory 5 is connected to the next layer directory (80
,89,...>. Here, the first directory 1 is made up of the next layer directory 80, the second directory 2 is made up of the next layer directory 8o, and the 2-2 directory 82, which is one sector of the next layer directory 89, is made up of the next layer directory 80. It consists of a lower directory 90. This lower directory 90
contains n files (85-88). The information in this file allows you to access the data.

FIG. 4(a) shows the format of one track in the directory section 23. This format allows one sector worth of information to be recorded on one track zero times, that is, in n sectors. When writing data to a card, directory information corresponding to this data is recorded in one sector.

FIG. 4(b) shows an example of directory information.

The directory information recorded in this figure includes information about the file such as file name (data block name) 51, file creation date 52, comment 55, and information about the recording position such as track number 53 where the file was recorded and file length 54. It is a combination. This information is stored in the lower directory. This lower directory is recorded according to predetermined search rules.

As an example of search rules, a search based on alphabetical order of file names will be described.

A lower directory with a file name starting with A is located under a certain upper directory.

This upper layer has a directory with a file name starting with A or B in the lower layer.

An example of the upper builer lift is shown in FIG. 4(c).

In this figure, names representing the lower directory are assigned to builf1 to name61. The first creation date 62 and the last creation date 63 indicate the range of dates when the file was created.

Comment 65 is an abbreviation to supplement Builev 1 to name 61. Directory position 64 indicates the track number of this directory.

When the upper directory track becomes full, a further upper directory is created. In this way, several levels of the edges of the block 1 are formed.

Next, operations during recording and retrieval on the optical card 20 will be explained based on a flowchart.

FIG. 5 shows a flowchart for recording data on the optical card 20. In this case, the search rule is alphabetical order of file names as an example of recording data.

First, record data in the recordable free data area.

Let the file name of this data be ABC.

In this case, the directory information of this file is recorded in a certain lower directory. This subdirectory is
In the tree structure, it is placed under the upper directory that indicates the file name starting with A. The directory information recorded is the file name (ABC) of this data, recording track number, etc. Note that the lower directory that stores this information uses unused sectors.

If the recorded sector is the last sector of the corresponding track, the upper directory located above this track is
Directory information for the entire track is recorded in a simplified form, such as the date of creation of the first file recorded on this track, the date of creation of the last file, and the name of a representative file. When all the sectors in the track of this upper directory have been recorded, the directory information of the entire track is further simplified and recorded in the upper directory located above this track.

The positions of the builfs 1 to 1 of each hierarchy within the directory section 23 on the optical card 20 are determined in advance according to the number of files that can be recorded. For example, if the tree structure has 3 levels and n =
], 6. Further, it is assumed that the direct 9 unit 23 starts from track number 1. In this case, the top floor control I/S 75 in FIG. 1(b) becomes track number 1. The next layer directory 80 has track number 2, and the next layer B-REF I/S 89 has l rack number 3, and the next layer directories are sequentially from 1 to rack number 17. Track number 17 and onwards are composed of lower layer directories. In this case, the number of 1 to 400 files composed of lower directories is 1.
62=256 pieces. The relays for all of these hierarchies are allocated in advance. This makes searching easier.

Furthermore, the search classification also needs to be determined in advance. For example, the first
Directory starts with A, second directory starts with B
Decide on something that starts with . However, the search classification may change during the process.

For example, there are many files starting with A, and the first directory cannot contain them. In this case, even if the search classification is changed such that the first directory starts with A, the second directory starts with A or B, etc., it will not make any difference.

On the other hand, the flowchart in FIG. 6 shows the operation when searching for a target file. As shown in this figure, we start by reading the top layer directory.

For example, suppose you want to search for a file called DEF. Assume that in the top layer directory 5, the first directory riff 1 has a file name starting with A or B, and the second directory riff 2 has a file name starting with C or D. In this case, the second directory 2 becomes the desired top layer directory. Next, the next layer directory 89 is read.

2-1 which is the first sector of this next layer directory 89
The directory 81 has a file name starting with C, and the second-second directory 82, which is the second sector, has a file name starting with D. Therefore, the 2-2nd directory 82 becomes the desired next layer directory. Finally, the lower directory 90 located under the 2-2 directory 82 is read out.

The directory of the desired file is sector - in this lower directory 90.

As will be explained below, each hierarchical directory can be divided into major categories (top layer directories), intermediate categories (next layer directories), and small categories (lower layer directories) in the search rules.

In the case of a three-layered directory as described above, in which 16 sectors can be recorded in one track, the number of files that can be managed is 163-212. For example, if an optical card has 2000 tracks and one file has the size of one track, it is possible to move to the target track with three accesses (seek operations). Furthermore, the seek operation for searching can be done within the directory section. Therefore, with this method, it is possible to search for the target file in a shorter time than with the method of searching the entire data section.

As described above, the optical recording medium according to the present invention is
The hierarchical directory is divided into n sections (one track has n sectors), and one layer consists of one track. As a result, compared to the conventional method of searching the entire data section, the search for the last recording l/rack and the file search can be processed efficiently and at high speed.

Note that various search classifications other than alphabetical order are possible. For example, there are classifications based on the date of creation, classifications based on image data and text data, and classifications based on individuals.

Furthermore, a configuration having two or more types of search classifications is also possible. For example, a first directory is used for searching by alphabetical order, and a second directory is used for searching by date. By using directories differently depending on their purpose in this way, more efficient data management can be achieved.

In this embodiment, an optical card is used as the optical recording medium. However, the optical recording medium according to the present invention can also be applied to optical disks and magneto-optical recording media.

[Effects of the Invention] As explained above, according to the present invention, since the directory section has a hierarchical directory structure, it is possible to search a large amount of data at high speed and manage data efficiently. .

[Brief explanation of the drawing]

1 to 7 relate to embodiments of the present invention, and FIG.
a) is a schematic diagram of the optical card, FIG. 1(b) is an explanatory diagram showing the relationship between directories in each hierarchy, FIG. ), Figure 4 is an explanatory diagram showing an example of the directory format, Figure 5 is a flowchart for recording data on an optical disc, and Figure 6 is a diagram showing the tracks on which files are recorded. It is a flowchart when searching. 20... Optical card 22... Track 23... Directory section 24... Data section 75... Top layer directory BO, 89... Next layer Direct 9 90... Lower layer directory Agent Patent attorney Ito Construction figure 2 figure 4 Gion 1 =582

Claims (1)

[Claims] An optical recording medium comprising: a data section for recording data; and a directory section capable of recording n sectors of directory information for managing this data in one track; A rule for searching is determined, the directory section is configured in a hierarchical tree structure according to the rule, and the directory information is recorded in the directory section or searched from the directory section based on the rule. optical recording medium.