KR20030083119A - Method for managing defect area of optical recording media - Google Patents

Abstract

PURPOSE: A defect area management method for an optical recording medium is provided to verify the defect existence of a target point in a bit map in the case of recording or reproducing, thereby simplifying the recognition of the existence of the defect and minimizing the operations and data access. CONSTITUTION: A defect area management method for an optical recording medium includes the steps of composing a defect area management list in the form of bit map, wherein the defect area management list represents whether a recording/reproducing unit is defective or not, and checking the defect existence of a corresponding area according to the list. The recording/reproducing unit is ECC block unit and the list is stored in a predetermined area of the recording medium.

Description

Method for managing defect area of optical recording media

The present invention relates to a rewritable optical recording medium recording and reproducing system, and more particularly to a method of managing a combined area of a rewritable optical recording medium.

Generally, rewritable discs include a rewritable compact disc (CD-RW) and a rewritable digital versatile disc (DVD-RAM, DVD + RW, DVD-RW). .

Such a disc usually consists of a lead-in area, a lead-out area, and a data area in which actual data is recorded.

In the case of the DVD + RW, a disc identification zone is provided in the lead-in and lead-out areas of the disc as shown in FIG.

In the case of the disc ID zone, 16 ECC blocks (= 256 sectors) are formed, and each ECC block is called a disc control block (DCB), and has control information according to information change of a disc. There are two types of DCBs: general purpose general DCBs and FDCBs with formatting information.

At this time, the first 4 bytes of the first physical sector (1 sector = 2048 bytes) of each DCB block is a content descriptor. If the value is 0x46444300, the ECC block is an FDCB.

2 is a format table of the FDCB, in which a content descriptor is 0x46444300. FDCB related information is recorded in the first physical sector, and formatting information of a disk is recorded in bitmap units in the second to tenth physical sectors.

In the case of a rewritable optical disc including a DVD + RW having the above-described structure, the recording / reproducing operation of information is repeatedly performed due to its use characteristics, which causes the mixture of the mixture constituting the recording layer formed for recording information on the optical disc. The mixing ratio is different from the initial mixing ratio and loses its characteristics, resulting in an error in recording / reproducing information.

This phenomenon is called deterioration, and this deteriorated area appears as a defect area when the optical disk is formatted, recorded, and reproduced.

In addition to the above-described deterioration phenomenon, the defective area of the rewritable optical disc may be generated due to scratches on the surface, dust such as dust, errors in manufacturing, and the like.

Therefore, in order to prevent data from being recorded / reproduced in the defect area formed due to the above reasons, it is necessary to manage the defect area.

In general, in order to manage defects in a DVD recording and reproducing system, a defect list is separately created and recorded in a defect management area of a disc, and when a disc is reproduced or recorded, a defect replacement block is used by referring to the defect list. have. At this time, even when the target point of the disc is reproduced and recorded (including the format), the defect list is first read to find out whether the target position is in the defect list, and then the recording or reproducing operation is performed. Thus, when there are a significant amount of defects, retrieving a large list of defects is inefficient.

However, since the defect list is a collection of defects that may be discontinuous, a process of searching for a target point corresponding to a defect must be performed every time.

In addition, whenever a new defect is found and added to the defect list, the trouble list has to be sorted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to configure a bitmap in a predetermined area of a disc for all ECC blocks of a disc, and then display the presence or absence of a defect of the corresponding ECC block on the bitmap. Disclosed is a defect area management method of an optical recording medium that simplifies a retrieval process.

1 shows the structure of a DVD + RW in a general rewritable disc.

2 is a view showing a format table of the FDCB of FIG.

3 is a view showing the structure of a DVD + RW according to the present invention

4 is a view showing a format table of the DFTDCB of FIG.

5 is a diagram illustrating an example of a defect bitmap of FIG. 4;

A defect area management method of an optical recording medium according to the present invention for achieving the above object comprises the steps of constructing a defect area management list in a bitmap format indicating whether a recording / reproducing unit for optical recording reproduction is defective; And determining whether there is a defect in the corresponding area according to the defect area management list.

In the list construction step, the recording / reproducing unit is an ECC block unit.

The defect management list is recorded and managed in a disc ID zone in a specific area on the optical recording medium, that is, a lead-in area and a lead-out area on the optical recording medium, and a block in which the defect management list is stored in the disc ID zone is a content descriptor. By using to distinguish from the other disk control block.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Hereinafter, with reference to the accompanying drawings illustrating the configuration and operation of the embodiment of the present invention, the configuration and operation of the present invention shown in the drawings and described by it will be described as at least one embodiment, By the technical spirit of the present invention described above and its core configuration and operation is not limited.

According to the present invention, in order to manage a defect of a disc, a bitmap of all ECC blocks of the disc is configured in a predetermined region of the disc, and then the presence or absence of a defect of the corresponding ECC block is displayed on the bitmap.

3 shows a layout of a disc according to the present invention, in which a bitmap for all ECC blocks is configured in a disc ID zone in a lead-in area and a lead-out area in order to manage defects.

That is, the present invention adds one more to the DCB type of the disc ID zone, and newly sets a DCB indicating defect related information of the disc. In the present invention, the name of this block is referred to as a defect DCB for convenience of explanation, and abbreviated as DFTDCB. In addition, as a content descriptor, ASCII code '44465400' indicating 'DFT' is used to distinguish it from other DCBs.

The format table of the DFTDCB is defined as shown in FIG. 4, which is consistent with the FDCB of FIG. 2. That is, when the first four bytes (D0 to D3) of the first sector record the content descriptor, and the 41st to 4 bytes (D40 to D43) of the first sector are defective and the bitmap type defect list is updated. It is a DFTDCB update count region that increases every time. According to the calculation result, if 9 sectors can indicate the presence or absence of defects in all ECC regions, a bitmap of a defective block is configured in the second to the tenth physical sectors (sectors 1 to 9).

FIG. 5 is a detailed table of the defective block bitmap of FIG. 4 and shows a defective bitmap for all areas of the disc. It is possible to know whether a corresponding ECC block is defective according to the value of each bit. In the present invention, in the embodiment, a bit value of 1 indicates a defect and 0 indicates a normal state.

That is, if a value of a specific bit in the bitmap is 1, the corresponding ECC block is determined to be defective. At this time, it is necessary to know where the ECC block of the target point to be reproduced or recorded corresponds to in the bitmap table to know whether there is a defect in the ECC block. In addition, when a new defect occurs, the bit value corresponding to the defect ECC may be corrected by knowing the corresponding position in the bitmap table.

In this case, the I-th ECC block from the first ECC block of the data region may be known by applying the following equation (1).

I = [(k-1) x 2048 + m] x 8 + n + 1

Where k = 1, ..., 9, m = 0, ..., 2047, n = 0, ..., 7.

That is, bit n of the main data byte Dm of sector k indicates the I-th ECC block from the bitmap start address.

At this time, if the bit value of the I-th ECC block is 1, it can be seen that the I-th ECC block is defective, and if 0, the I-th ECC block is normal.

In addition, by reading the m-th byte of the k sector corresponding to the I-th ECC block, it is possible to check whether there are any defects of eight ECC blocks including the I-th at a time with '0' of this value, and the nth bit of the read value The position of the defective ECC block indicating can be easily identified.

When a new defect is generated, it is only necessary to find a bit at a position corresponding to the ECC block in which the defect is generated by Equation 1 and change the value from 0 to 1. In other words, a sorting process is not necessary each time a new defect is found and the defect list is updated.

In this case, only the value of the DFTDCB update count region needs to be increased.

It also provides ease of managing defect lists in physical format. When sorting the defect position information newly added to each physical format each time according to the bitmap order, the defect list can be sorted quickly.

The application of DVD + RW in the present invention is one embodiment, and is applicable to all optical recording and reproducing systems for performing defect management.

In addition, the defect management list of the present invention expressed in the bitmap format can be recorded and managed not only in the optical disc including the disc ID zone described above, but also in a specific area such as a memory in the optical recorder.

As described above, according to the method for managing a defective area of an optical recording medium according to the present invention, by configuring a bitmap for all ECC blocks of a disc in a predetermined area of the disc, and displaying the presence or absence of a defect of the ECC block on the bitmap, When recording or reproducing, it is possible to verify the presence or absence of a target point in the bitmap in the bitmap, thereby minimizing operation and data access while easily identifying the target point.

In addition, since the presence or absence of a defect in the target point in the bitmap can be known in advance during recording or reproduction, it is possible to prepare for filter adjustment or the like in advance.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (6)

Constructing, in a bitmap format, a defect area management list indicating whether or not a recording reproduction unit for optical recording reproduction is defective; And And determining whether there is a defect in the corresponding area according to the defect area management list. The method of claim 1, And the recording / reproducing unit in the list construction step is an ECC block unit. The method of claim 1, And the defect management list is stored and managed in a specific area on the optical recording medium. The method of claim 3, wherein And the specific area is a disc ID zone in the lead-in area and the lead-out area on the optical recording medium. The method of claim 4, wherein And a block in which the defect management list is stored in the disc ID zone is distinguished from other disc control blocks by using a content descriptor. The method of claim 2, And detecting a position of a bitmap indicating whether a specific ECC block is present in the defect management list by applying the following equation. I = [(k-1) x 2048 + m] x 8 + n + 1 Where sector k = 1, ..., 9, main data byte m = 0, ..., 2047, bit n = 0, ..., 7.