HK1089859B - Recording apparatus and reproducing apparatus - Google Patents

Description

Recording apparatus and reproducing apparatus

Technical Field

The present invention relates to a method and apparatus for recording and/or reproducing data in units of a predetermined size on an information storage medium, and the information storage medium.

Background

Recording and/or reproducing data on an information storage medium such as an HD-DVD, a CD, or a DVD is performed in units of a predetermined size. The unit is referred to as a recording unit block or a reproducing unit block. An example of the recording unit block or the reproducing unit block is an error correction block for correcting an error generated when data is recorded or reproduced.

Assuming that the size of the error correction block is 64 kbytes, when data of only 4 kbytes in size, which does not correspond to the entire error correction block but to portions of the error correction block, is to be recorded, the remaining portion (60 kbytes) will be filled with invalid values.

If the disc drive reads out the error correction block to reproduce valid data occupying only a portion of the block and performs error correction, error correction of codewords containing meaningful 4 kbytes of data is possible, but error correction of codewords containing meaningless 60 kbytes of data is not possible, with the result that it is determined that error correction is not possible in the entire error correction block. Since the disc drive cannot distinguish which part of the error correction block has valid data and which part is filled with invalid data, error correction or reproduction should be retried, otherwise, although the error correction block contains some valid data, it is finally regarded as an error block.

Disclosure of Invention

An aspect of the present invention provides an apparatus and method for recording and/or reproducing data, by which a disc drive can distinguish valid data from invalid data in an error correction block, so that the reliability of reproduction increases and the stability of a system can be guaranteed, and a corresponding information storage medium.

According to an aspect of the present invention, there is provided a recording method including: recording a recording unit block in which invalid data is padded in a portion; and recording filling information, wherein the filling information indicates that invalid data is included.

According to an aspect of the invention, in the recording of the padding information, the padding information is recorded to correspond to at least one recording unit block, to correspond to at least one reproducing unit block, or in the recording unit block.

According to an aspect of the invention, the recording of the padding information comprises: recording information indicating whether padded data is present in at least one recording unit block or reproducing unit block corresponding to the padding information, or recording information indicating a position of the padded data in at least one recording unit block or reproducing unit block corresponding to the padding information, or recording information indicating a value of the padded data in at least one recording unit block or reproducing unit block corresponding to the padding information.

According to another aspect of the present invention, there is provided a reproducing method including: reading at least one recording unit block in which valid data is included in a portion of the recording unit block and invalid data is padded in the remaining portion thereof; and obtaining valid data based on the padding information.

According to another aspect of the invention, the recording unit block is an error correction block.

According to an aspect of the invention, the obtaining of the valid data comprises: the recorded padding information corresponding to at least one reproducing unit block is read from the information storage medium, or the padding information recorded in the recording unit block is read.

According to another aspect of the present invention, the obtaining of the valid data includes: it is determined from the padding information whether there is data padded in at least one recording unit block or reproducing unit block corresponding to the padding information, and if there is padded data, valid data excluding the padded data is obtained, or a position of the data padded in at least one recording unit block or reproducing unit block corresponding to the padding information is searched for from the padding information, and valid data excluding the padded data is obtained, or a value of the data padded in at least one recording unit block or reproducing unit block corresponding to the padding information is searched for from the padding information, and valid data excluding the padded data is obtained.

According to another aspect of the present invention, there is provided a recording apparatus including: a pickup unit recording data on a disc; and a control unit controlling the pickup unit to record data in the recording unit block and to record padding information, invalid data being padded in a portion of the recording unit block, the padding information indicating that the invalid data is included in the recording unit block.

According to another aspect of the present invention, there is provided a reproducing apparatus including: a pickup unit reading at least one recording unit block in which valid data is included in a portion of the recording unit block and invalid data is padded in a remaining portion thereof; and a control unit obtaining the valid data based on the padding information.

According to another aspect of the present invention, there is provided an information storage medium including: a recording unit block in which valid data is included in a portion of the recording unit block and invalid data is padded in a remaining portion thereof; and padding information indicating that invalid data is included.

According to an aspect of the present invention, padding information is recorded to correspond to at least one recording unit block, to correspond to at least one reproducing unit block, or in a recording unit block.

According to an aspect of the invention, the padding information comprises: information indicating whether there is data padded in at least one recording unit block or reproducing unit block corresponding to the padding information, or the padding information further includes: at least one of information indicating a position of the padded data and information indicating a value of the padded data.

Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

FIG. 1 is a block diagram of an apparatus according to the present invention;

FIG. 2 is a block diagram of a disk drive to which the apparatus of FIG. 1 is applied;

fig. 3A to 3G are reference diagrams showing padding information according to an embodiment of the present invention;

FIG. 4 is a reference diagram for explaining an implementation of the present invention;

FIG. 5 is a schematic representation of a conventional overall encoding process; and

fig. 6 shows a conventional composition of data sectors of two data frames.

Detailed Description

Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures.

Referring to fig. 1, an apparatus according to an embodiment of the present invention, which is capable of recording and/or reproducing data, includes a writing/reading unit 1 and a control unit 2. The writing/reading unit 1 records data on a disc 100 according to the control of the control unit 2, and reads out the data to reproduce the recorded data, the disc 100 being an information storage medium according to an embodiment of the present invention. The control unit 2 controls the recording/reproducing unit 1 so that the writing/reading unit 1 records data in a predetermined recording unit block, or the control unit 2 processes data read by the writing/reading unit 1 and obtains valid data. The reproduction refers to obtaining valid data by performing error correction on the read data, and the reproduction is performed in a predetermined unit. A unit for performing reproduction is referred to as a reproduction unit block. The reproducing unit block corresponds to at least one recording unit block.

In a data recording operation, when the control unit is recording data on the disc 100 that cannot fully fill the recording unit block size, valid data is stored in a portion of the recording unit block and invalid data is padded in the remaining portion to form a recording unit block of a predetermined size, and then this unit block is recorded. Further, padding information indicating that invalid data is contained is recorded on the disc 100. In the embodiment shown in fig. 1, padding information is recorded in the recording unit block. The padding information is not limited to indicating that invalid data is included, or information that enables valid information to be distinguished from invalid information. This will be explained in more detail later.

In a data reproducing operation, the write/read unit 1 reads out at least one recording unit block, in which valid data is included in a portion of the block and invalid data is padded in the remaining portion of the block, from the disc 100. The control unit 2 extracts only valid data based on padding information contained in the recording unit block and reproduces the valid data.

Fig. 2 is a block diagram of a disc drive to which the apparatus of fig. 1 is applied. Referring to fig. 2, the disc drive includes a pickup 10 as a writing/reading unit 1. The disc 100 is placed on the pickup 10. In addition, the disk drive includes a PC I/F21, a DSP22, an RFAMP 23, a servo 24, and a system controller 25 as the control unit 2. The system controller 25 performs initialization required for recording data.

In the data recording operation, the PC I/F21 receives a recording command and data to be recorded from the host. The DSP22 adds additional data such as parity for error correction of the data received from the PC I/F21, performs Error Correction and Check (ECC) encoding to generate an ECC block as an error correction block, and modulates the ECC block in accordance with a predetermined method. Here, if the data to be recorded is smaller than the size of the ECC block, the invalid data is padded to form a complete ECC block together with the data smaller than the size of the ECC block. The padding information may be added before or after ECC encoding is performed. The RF amp 23 converts data output from the DSP22 into an RF signal. The pickup 10 records the RF signal output from the RF AMP 23 on the disc 100. The servo 24 receives a command required for servo control from the system controller 25 and servo-controls the pickup 10.

In the data reproduction operation, the PC I/F21 receives a reproduction command from a host (not shown). The system controller 25 performs initialization required for reproduction. The pickup 10 emits a laser beam onto the disc 100, obtains an optical signal by receiving the beam reflected from the disc 100, and outputs the optical signal. The RF AMP 23 converts an optical signal output from the pickup 10 into an RF signal, and supplies modulated data obtained from the RF signal to the DSP22 while supplying a servo signal for controlling the pickup obtained from the RF signal to the servo 24. The DSP22 demodulates the modulated data, performs error correction, and outputs the final data. In the case of an ECC block in which valid data is recorded only in a portion thereof, only the valid data is reproduced by referring to the padding information.

Meanwhile, the servo 24 performs servo control of the pickup 10 by using the servo signal received from the RFAMP 23 and a command required for servo control received from the system controller 25. The PC I/F21 transfers data received from the DSP22 to the host.

Fig. 3A to 3G are reference diagrams showing padding information according to an embodiment of the present invention.

Fig. 3A shows padding information recorded in each recording unit block. Therefore, padding information corresponds to each recording unit block. That is, padding information is recorded in each recording unit block. A recording unit block is a unit for recording data, and generally has a predetermined size.

As shown in fig. 3B, the recording unit blocks are divided into groups including a predetermined number of recording unit blocks, and padding information is recorded in each group. Thus, the padding information corresponds to a plurality of recording unit blocks. That is, padding information is recorded in each group of recording unit blocks.

As shown in fig. 3C, padding information is recorded in every two recording unit blocks.

As shown in fig. 3D, padding information is recorded in each reproducing unit block. The reproducing unit block corresponds to at least one recording unit block. Therefore, padding information can be actually recorded in one recording unit block or outside one recording unit block.

As shown in fig. 3E, the padding information reproducing unit blocks are divided into groups including a predetermined number of reproducing unit blocks, and padding information is recorded in each of the groups of reproducing unit blocks.

As shown in fig. 3F, padding information is recorded in every two reproducing unit blocks.

As shown in fig. 3G, the padding information includes padding presence information 350, padding position information 360, and a padding value 370. The padding presence information 350 indicates whether there is padded data. The padding position information 360 indicates the positions of valid data and invalid data in the recording unit block. The padding value 370 indicates a padded value. Recording the padding values 370 is not necessary if the padded values are predetermined.

The disc drive of fig. 2 is able to extract valid data from a recording unit block by means of padding information. In particular, when the recording unit block is an error correction block, although errors in codewords including only invalid data may not be corrected, if errors in a plurality of codewords containing valid data can be corrected, the errors in the codewords may be corrected, so that valid data is extracted and transmitted to the host. When the entire recording unit block is transferred, a portion corresponding to invalid information and a portion containing padded values when data is recorded are transferred without change.

Referring to fig. 2, based on the padding information having the above-described structure, the operation of the disc drive will now be explained in more detail.

Since the amount of management information for smoothly using the disc 100, which is generally recorded in the lead-in or lead-out area of the disc 100, is smaller than the size of a recording unit block (e.g., 64 kbytes), the system controller 25 fills the remaining portion with a predetermined value such as 00h so that a recording unit block of a predetermined size can be formed and transferred to the pickup 10. Further, when data is recorded in accordance with a recording command of the host, and when the size of the recorded data is not a multiple of the recording unit block, the system controller 25 receives the data transmitted from the host, divides the data to fit the size of the recording unit block, and then records the data. As for the remaining portion of the recording unit block, which is not filled with data, the system controller 25 pads the portion with a predetermined value, such as 00h, so that a recording unit block of a predetermined size can be formed and can be transferred to the pickup 10. Therefore, a position just before the 00h padded area in the recording unit block is the last part of the area where valid data is recorded.

When a part of the recording unit block is padded with a predetermined value such as 00h, the system controller 25 records padding information together so that the presence of padded invalid data and the positions of valid data and invalid data in the recording unit block are indicated, and the value of the invalid data (i.e., the padded value; e.g., 00h if 00h is padded or ffh if ffh is padded) is recorded. Therefore, the position where valid data exists in the recording unit block indicates the position where valid data is recorded in the recording unit block, and the position where invalid data, for example, 00h exists indicates the position where invalid data is recorded in the recording unit block. Therefore, the positions of the valid data and invalid data in the recording unit block indicate the positions to which the valid data is recorded and beyond which the invalid data is recorded.

Specific examples of implementations of embodiments of the present invention will now be explained in detail.

< recording of filling information >

A "data frame" is a term used in U.S. patent No. 6,367,049, which indicates a 2K byte block of data, typically a 2K byte sector. Fig. 5 is a schematic representation of a conventional encoding process. Referring to fig. 5, the ECC format includes an ECC cluster 510 formed of 304 long-distance Reed-Solomon error correction codes and a Burst Indicator Subcode (BIS) cluster 516 formed of 24 burst indicator subcodes.

Referring to fig. 4 and 5, in generating the BIS cluster 516, a predetermined portion of "control data" of the "logical address + control data" 502 may be allocated to the padding presence information 350 and the padding value 370 for a sector unit 2 kbytes long to implement an embodiment of the present invention. For padding presence information 350 (e.g., '1' indicates that there is padded data, and '0' indicates that only normal data is present), one sector ("data frame") 2 kbytes long requires 1 bit, and thus 32 bits (4 bytes). For the padding value 370, 1 byte is required per sector, and thus 32 bytes are required. When the padding value 370 is selected among some predetermined values, it is desirable, but not necessary, to record information indicating the predetermined values. (for example, if there are two values 00h and ffh that can be padded in a sector cell, the padding value can be identified by only one bit indicating '0' or '1')

In short, 4-byte padding presence information is recorded in "control data" of "logical address + control data" 502, a 32-byte padding value 370 is recorded in "control data" of "logical address + control data" 502, and information indicating the padding value 370 is allocated to "control data" of "logical address + control data" 502.

When the padding value 370 is determined to be a predetermined value, only padding presence information 350 needs to be recorded. In this case, as shown in fig. 5, padding presence information 350 may be stored in a "physical address" 504(16 × 9 bytes). It is assumed that, for example, a recording unit block has 16 "physical addresses" 504 corresponding to 16 physical sectors, and thus, one "physical address" 504 may be 9 bytes, and then padding information 350 corresponding to 2 data frames may be recorded in the recording unit block.

In short, the recording unit block shown in fig. 5 has 32 "data frames" including data frames 0 to 31, and thus padding presence information 350 can be recorded in the nth (N ═ 0, 1, 2., 15) physical address among 16 "physical addresses" 504.

< filling information recording operation >

In the structure of recording data in the ECC format, in order to record data on the disc 100, user data is encoded with an error correction code to form an "ECC cluster" 510, and in addition, a "BIS cluster" 516 is generated to form a recording unit block. In performing the above process, information indicating whether to fill each "data frame" of the "user data 32 frame" 500(64 kbytes) in fig. 5 with a predetermined value is stored in a portion of the "physical address" 504(16 × 9 bytes) or the "logical address + control data" 502(32 × 18 bytes).

The host may communicate data with a disk drive (not shown) in units of sectors, where 1 sector is 2 kbytes. For example, if the host commands the disc drive to record 50 sectors, then for the remaining 18 sectors, the disc drive itself fills the data corresponding to 14 sectors with a predetermined value, such as 00 h. Since the disc drive knows that data is padded, according to an embodiment of the present invention, the disc drive includes and records padding presence information 350 and a padding value 370 as padding information for each sector at a "logical address + control data" 502(32 × 18 bytes) or a "physical address" 504(16 × 6 bytes).

When the host forms data into recording unit blocks and transmits the data to the disc drive, the disc drive does not know whether the data is padded. Therefore, in this case, the host should inform the disc drive of this fact.

When a disc drive records management information on a disc to manage the disc under the control of the disc drive itself, the disc drive has already learned the amount of data to be recorded and determined whether to fill the data, although there is no recording command from the host. Therefore, as described above, the disc drive can record padding presence information and a padding value together as padding information for each sector on the disc.

< filling information reproducing operation >

Fig. 6 shows a conventional composition of data sectors of two data frames. Referring to fig. 6, when user data recorded in a data area of a disc is reproduced in response to a reproduction command from a host or when a disc drive reproduces data without a reproduction command of the host to obtain disc management information recorded in a lead-in or lead-out area of the disc, data is read out in units of recording or reproducing unit blocks from the disc and error correction is performed. In performing the above process, if data is recorded in the ECC format as shown in fig. 5 and 6, error correction is first performed on the "BIS block" 514 obtained by deinterleaving the "ECC cluster" 510. The disc drive obtains padding presence information 350 and a padding value 370 for each sector (2 kbytes) as padding information stored in a "logical address + control data" 502(32 × 18 bytes) or a "physical address" 504(16 × 9 bytes) by performing error correction on the "BIS block" 514. If the error correction of the "BIS block" 514 is completed, the error correction is performed on the "LDC block" 508. The "data block" 506 obtained before ECC encoding the "LDC block" 508 is obtained in the same manner except that "19 columns" in fig. 6 is changed to "304 columns".

Since the disc drive already knows the padding presence information 350 and the padding value 370 for each "data frame", the disc drive is able to distinguish between code words containing valid information and code words containing invalid information on the "LDC block" 508. At this time, if errors in codewords containing valid information can be corrected, even when there are codewords containing only invalid information (i.e., filled data frames) and errors in the codewords cannot be corrected, the errors can be corrected. Then, if a reproducing operation is performed in response to a reproducing command of the host, the corrected valid information is transmitted to the host, and if the disc drive itself automatically performs the reproducing operation, the information is used as it is.

Meanwhile, in the disc structure in which the linking areas are disposed between the recording unit blocks, the padding information described above may be recorded in the linking areas, and the padding information may be utilized when data is reproduced. In order to increase the reliability of data, it is preferable, but not necessary, that the padding information read out from the link zone be also error-corrected.

Fig. 4 is a reference diagram for explaining implementation of the present invention. Referring to fig. 4, after the "BIS cluster" 514 is reproduced, the validity of data corresponding to each "data frame" is known, and it is known that only the first two "data frames" contain valid information. Fig. 4 shows an "LDC block" 508 to be error corrected in this case.

If errors in 19 code words corresponding to the first two data frames in the "LDC block" 508 can be corrected, the error correction system transmits data corresponding to the first two data frames regardless of whether errors in code words corresponding to the invalid 30 data frames are corrected, and transmits the remaining 30 data frames as padding values when data is recorded, if necessary.

If the recording method suggested by the embodiment of the present invention is not applied when recording data, the disc drive having the error correction system cannot understand the situation shown in fig. 4 at all. Thus, even if errors in 19 code words corresponding to two "data frames" can be corrected, if errors in any remaining code words cannot be corrected, the disc drive reads out data again from the disc and performs error correction or discards the block as an erroneous block.

Meanwhile, in the reproduction-only disc, padding information according to the present invention may be recorded when data is stored during the manufacture of the disc, so that data reproduction efficiency may be improved.

According to the present invention described above, the disc drive can distinguish valid data from invalid data in the error correction block, so that the reliability of reproduction increases and the stability of the system can be ensured.

Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.

Claims (12)

1. A recording apparatus, comprising:

a pickup unit recording data on a disc; and

a control unit controlling the pickup unit to record data in a recording unit block on the disc, the recording unit block including valid data and/or invalid data, and to record padding information indicating whether the recording unit block includes invalid data.

2. The recording apparatus of claim 1, wherein the control unit records the padding information corresponding to at least one recording unit block.

3. The recording apparatus of claim 1, wherein the control unit records the padding information in the recording unit block.

4. The recording apparatus of claim 1, wherein the padding information includes information indicating whether the padded invalid data is in at least one recording unit block.

5. The recording apparatus of claim 4, wherein the padding information includes information indicating a location of the padded invalid data in at least one recording unit block.

6. The recording apparatus of claim 1, wherein the padding information includes information indicating a value of the padded invalid data in at least one recording unit block.

7. The recording apparatus of claim 5, wherein the information indicating the location of the padded invalid data is used to find a last location of valid data last recorded on the disc.

8. A reproduction apparatus comprising:

a pickup unit reading data from an information storage medium; and

a control unit controlling the pickup unit to read a recording unit block including valid data and/or invalid data and padding information indicating whether the recording unit block includes the invalid data from an information storage medium.

9. The reproducing apparatus of claim 8, wherein the pickup unit reads the padding information recorded in the recording unit block from the information storage medium.

10. The reproducing apparatus of claim 8, wherein the control unit determines from the padding information whether there is data padded in at least one recording unit block corresponding to the padding information, and if there is padded data, obtains valid data excluding the padded data.

11. The reproduction apparatus according to claim 8, wherein information indicating a position of the padded invalid data is obtained from the padding information.

12. The reproducing apparatus of claim 11, wherein the information indicating the location of the padded invalid data is used to find a last location of valid data last recorded on the information storage medium.