CN1877728A - Data Recovery Method for Optical Discs with Damaged Table of Contents - Google Patents

Abstract

The invention provides a data recovery method, which utilizes an optical disk drive to recover data on an optical disk with a damaged directory table area. The method includes identifying a last valid directory table block from the directory table area, and finding a last known segment according to the directory table block. The last known segment is considered a last possible segment. After the judgment, if an area of the last possible sector recording at least one sector of the disc control block is full, detecting whether a next sector exists. If the next sector exists, the detected next sector is regarded as the last possible sector again until the last possible sector with full areas for recording the multiple sectors of the disc control blocks is found.

Description

Data Recovery Method for Optical Discs with Damaged Table of Contents

technical field

The present invention relates to a data restoration method, which uses an optical disc drive (Optical disc drive) to restore data on an optical disc (Optical disc) with a damaged Table-of-contents (TOC) area.

Background technique

Each optical recording medium for data recording has an area for storing session data. For example, on a DVD+R disc, session data is stored in a table of contents area. When a user puts a DVD+R disc into an optical disc drive, the optical disc drive reads a latest table of contents block (block) in the table of contents area to obtain the data of the session. However, the latest table of contents block is sometimes lost, unreadable or incorrect in data. If the user puts the optical disc with the above situation into the optical disc drive, the optical disc drive will not be able to read the data in the optical disc due to sector data errors. As a result, although the data stored in this CD is complete, it still cannot be obtained by the CD drive.

In order to successfully read the data in the optical disc, the present invention provides a data recovery method, which finds correct and valid segment data from other storage areas of the optical disc, so that the data stored in the optical disc can still be obtained by the optical disc drive.

Contents of the invention

The present invention provides a data restoration method, which utilizes an optical disk drive to restore data on an optical disk with a damaged table of contents area.

The method is, firstly, identifying a last valid TOC block (Latest valid TOC block) from the TOC area. Then, find out a last known section (Last known session) according to the last valid table of contents block, and regard the last known section as a last possible existing section (Last possible session) . It is judged whether an area of at least one session disc control block (Session disc control block, SDCB) for recording the last possible session is full. If the judgment result is affirmative, then check whether the next session (Next session) exists based on the segment disc control block of the last possible segment. If the next section exists, then the detected next section is regarded as the last possible section again, and the above-mentioned judging steps are repeated until a final section is found, that is, the last section The area for recording the control block of the multi-session disc is not full.

The data restoration method of the present invention utilizes the characteristics of storing data in different regions of the optical disk to restore the damaged segment data in the table of contents region. When the table of contents area is damaged, the segment data can be retrieved from other areas of the optical disc, so that the user can continue to use the optical disc and record data on it.

The advantages and spirit of the present invention can be further understood through the following detailed description of the invention and the accompanying drawings.

Description of drawings

FIG. 1 shows a flowchart illustrating the procedure of a data restoration method according to a preferred embodiment of the present invention.

FIG. 2 shows a flow chart illustrating the procedure for the optical disc drive to record the recovered segment data into the optical disc.

Description of main component symbols

S10-S16: Process steps

S20-S26: Process steps

Detailed ways

The present invention aims to provide a data restoration method, which uses an optical disk drive to restore data on an optical disk with a damaged table of contents area.

The method is, firstly, identifying a last valid directory block from the directory area. Then, according to the last valid table of contents block, a last known segment is found, and the last known segment is regarded as a last possible existing segment. It is judged whether an area of the control block of the at least one session optical disc for recording the last possible session is full. If the judging result is affirmative, then based on the data in the sector disc control block of the last possible sector, it is detected whether the next sector exists. If the next section exists, then the detected next section is regarded as the last possible section again, and the above-mentioned judging steps are repeated until a final section is found, that is, the last section The area for recording the control block of the multi-session disc is not full.

The present invention infers whether there is a next segment by judging whether the area storing the segment disc control block in the segment of the optical disc is full or not. This is because when the area of the control block of the storage segment optical disc is full, the segment cannot record more fragment information (Fragment information), so the segment should be a closed segment. When data can no longer be recorded in a closed section, a new section should be opened after the closed section to store more data on the optical disc.

Please refer to FIG. 1. FIG. 1 shows a flow chart illustrating the procedure of a data recovery method according to a preferred embodiment of the present invention. In this preferred embodiment, the disc is a DVD+R disc.

First, step S10 is executed to extract a last physical TOC block from the TOC area as a currently processed TOC block. Then step S11 is executed to determine whether the currently processed table of contents block is valid. If the table of contents block of this current processing is invalid, then execute step S12, extract the previous table of contents block of the table of contents block of this current processing, regard this previous table of contents block as the table of contents of this current processing again block, and repeat steps S11 to S12 until a valid table of contents block is found. If the table of contents block of this current processing is valid, then execute step S13, the table of contents block of this current processing is regarded as this last effective table of contents block, and according to this last effective table of contents block, find out a Last known segment. The last known segment is considered a last possible segment. Then step S14 is executed to determine whether an area of at least one section optical disc control block for recording the last possible section is fully loaded. In this embodiment, this area is the last possible section in the - Inner disc/session identification zone. If the result of S14 is negative, execute step S16 to end the data recovery procedure. If the result of S14 is affirmative, then execute step S15 to check whether the next section exists. If the next section does not exist, execute step S16 to end the data restoration procedure. If the next section exists, the detected next section is regarded as the last possible section again, and step S14 to step S15 are repeated until the result of step S15 is negative.

When the optical disk drive completes the above-mentioned data recovery procedure, the complete segment data can be obtained. Moreover, the optical disc drive can read the data stored in each segment of the optical disc according to the segment data. The procedure for recording the restored segment data into the optical disc by the optical disc drive will be described below.

Please refer to FIG. 2 . FIG. 2 shows a flow chart illustrating the procedure for the optical disc drive to record the recovered segment data into the optical disc. The optical disc drive includes a disc file (Disc file) for storing the last valid table of contents block. Firstly, after the optical disk drive recognizes the last valid directory block from the table of contents area, step S20 is executed to store the last valid directory table block into the optical disc file. When the optical disc drive determines that the area for recording at least one disc control block in the last possible section is fully loaded, step S22 is executed, and the last possible section is regarded as a closed section . Immediately execute step S24, according to the section disc control block of the last possible section, update or add a management information (Management information) about the last possible section to the disc file in the optical disc drive . Finally, step S26 is executed, the optical disc drive records the optical disc file into the table of contents area of the optical disc to become a new table of contents block.

The optical disc drive can also record a new data to the optical disc. And, during the process of recording the new data on the optical disc, management information about the new data can be appended to the optical disc file in the optical disc drive. After finishing recording the new data on the optical disc, the optical disc drive records the optical disc file into the table of contents area of the optical disc to become a new table of contents block.

Through the above detailed description of the preferred embodiments, it is hoped that the features and spirit of the present invention can be described more clearly, rather than limiting the scope of the present invention by the preferred embodiments disclosed above. On the contrary, the intention is to cover various modifications and equivalent arrangements within the scope of the appended claims.

Claims (8)

1, a kind of data recovery method, this method utilize a CD drive to restore data that have on the CD in a catalogue listing zone of damaging, and this method comprises the following step:

(a) from this catalogue listing zone, identification one last effectively catalogue listing block;

(b) according to should last effectively catalogue listing block, find out a last known section, and will be somebody's turn to do at last that known section is considered as a section that may exist at last;

(c) whether judgement is fully loaded for a zone of at least one section CD control block of this section that may exist at last of record;

(d) if whether the result of step (c) for certainly, controls block detection one next section based on the section CD of this section that may exist at last and exists; And

(e) if the result of step (d) for certainly, is considered as the section that this may exist at last with this detected next section again, and repeating step (c) arrives step (e) till the result of step (c) is to negate.

2, the method for claim 1, wherein in step (a), an optical file is opened in this CD drive should last effectively catalogue listing block with storage.

3, method as claimed in claim 2, wherein step (d) and execution the following step:

This section that may exist at last is considered as the section of a sealing, and according to the section CD of this section that may exist at last control block, upgrade or an additional management information this optical file to this CD drive about this section that may exist at last in.

4, method as claimed in claim 3, wherein this CD drive can be recorded to this optical file in this catalogue listing zone of this CD and become a new directory list area piece.

5, method as claimed in claim 3, this CD drive and write down a new data to this CD wherein, in the process in this new data of record to this CD, be attached in this optical file in this CD drive about the management information of this new data, in finish this new data of record to this CD after, this optical file is recorded to and becomes a new directory list area piece in this catalogue listing zone of this CD.

6, the method for claim 1, wherein step (a) is carried out with the following step:

(a1) this catalogue listing location is certainly extracted the catalogue listing block of a last in esse catalogue listing block as an existing processing;

(a2) judge whether the catalogue listing block of this existing processing is effective;

(a3) if the result of step (a2) for certainly, is considered as this last effectively catalogue listing block with the catalogue listing block of this existing processing; And

(a4) if the result of step (a2) is for negating, extract the previous catalogue listing block of the catalogue listing block of this existing processing, again the catalogue listing block section of being extracted in the step (a4) is considered as the catalogue listing block of this existing processing, and repeating step (a2) arrives step (a4) till the result of step (a2) is to affirm.

7, the method for claim 1, wherein this CD is a DVD+R CD.

8, the method for claim 1, wherein at least one section CD control of this of this section that may exist at last block is recorded in the inner disc section identified region of this section that may exist at last.

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