SPLICELESS EDITING OF A READ/WRITE OPTICAL MEDIUM

• US 20020126595A1
• Filed: 01/14/1999
• Published: 09/12/2002
• Est. Priority Date: 01/14/1999
• Status: Active Grant

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: HOGAN, JOSHUA N.
• Granted Patent: US 6,501,721 B2
• Time in Patent Office: Days
• US Class Current: 369/47.13
• CPC Class Codes: G11B 20/1251 for continuous data, e.g. digitised analog information signals, pulse code modulated [PCM] data
• CPC Class Codes: G11B 20/1423 Code representation depending on subsequent bits, e.g. delay modulation, double density code, Miller code
• CPC Class Codes: G11B 20/18 Error detection or correction; Testing , e.g. of drop-outs
• CPC Class Codes: G11B 2020/1268 Address in pregroove [ADIP] information
• CPC Class Codes: G11B 2020/1277 for managing gaps between two recordings, e.g. control data in linking areas, run-in or run-out fields, guard or buffer zones
• CPC Class Codes: G11B 2020/1287 Synchronisation pattern, e.g. VCO fields specific bit sequences of sync patterns G11B20/1403; A/V synchronisation G11B27/00
• CPC Class Codes: G11B 2020/1292 Enhancement of the total storage capacity
• CPC Class Codes: G11B 2220/216 Rewritable discs
• CPC Class Codes: G11B 2220/2545 CDs
• CPC Class Codes: G11B 2220/2562 DVDs [digital versatile discs]; Digital video discs; MMCDs; HDCDs
• CPC Class Codes: G11B 2220/257 DVDs belonging to the plus family, i.e. +R, +RW, +VR
• CPC Class Codes: G11B 2220/2575 DVD-RAMs
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/036 Insert-editing
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: G11B 7/00745 Sectoring or header formats within a track formats in general G11B20/12

Abstract

An optical read/write drive such as a DVD+RW drive writes a block of new data to a read/write medium by locating an edit bit in the block of data that has already been written to the medium, and writing the block of new data to the medium, beginning or ending at the edit bit. The edit bit may be chosen to avoid errors arising from polarity conflicts between data already written to the disc and the new data. The edit bit could be, for example, a differing transition bit in a sync codeword of a modulation-encoded block.

Claims

1. A method of writing a first block including new data to a read/write optical medium, a second block including old data having already been written to the medium, the method comprising the steps of:

locating an edit bit in the second block; and

writing the first block to the disc, one of beginning and ending of the writing occurring at the edit bit;

whereby at least a portion of the second block is overwritten.

2. The method of claim 1, wherein each block includes a sync codeword, the sync codeword having a differing transition bit, and wherein the edit bit is the differing transition bit.

3. The method of claim 1, the block including a sync codeword, a portion of the sync codeword having a predetermined polarity, wherein the edit bit is a bit in the portion having the predetermined polarity.

4. The method of claim 1, the block including a header, the header having a reserved area, a codeword having a differing bit being stored in the reserved area, wherein the edit bit is the differing bit of the codeword.

5. The method of claim 1, the block having a last line providing error correction capability, the edit bit being in the last line of the block, whereby at some of the error correction capability is lost.

6. The method of claim 5, wherein at least some of the last line is filled with data that allows for data recovery clock stabilization.

7. The method of claim 5, wherein the edit bit is located to introduce a large random phase discontinuity in the last line.

8. The method of claim 1, wherein the edit bit is located by using a high frequency reference signal and addressing information.

9. Apparatus for writing data to a read/write optical disc, the apparatus comprising:

a laser;

a laser driver for the laser; and

means for locating an edit bit on the disc and commanding the laser driver to cause the laser to write the data to the disc with bit accuracy, one of the beginning and ending of the writing occurring at the edit bit.

10. The apparatus of claim 9, wherein the means is configured to locate the edit bit by using a high frequency reference signal and addressing information.

11. The apparatus of claim 9, wherein the means is configured to make the edit bit the differing transition bit of a sync codeword.

12. The apparatus of claim 9, wherein the means is configured to make the edit bit a bit within a portion of a sync codeword, the portion having a predetermined polarity, the means writing the edit bit using the predetermined polarity.

13. The apparatus of claim 9, wherein the means is configured to make the edit bit a differing bit of a codeword that is stored in a reserved area of a header.

14. The apparatus of claim 9, the old data being arranged in a block, a last line of the block providing error correction capability, wherein the means is configured to locate the edit bit in the last line of the block.

15. The apparatus of claim 14, wherein the means fills at least some of the last line with data that allows for data recovery clock stabilization.

16. The apparatus of claim 14, wherein the edit bit is located to introduce a large random phase discontinuity in the last line.

18. The drive of claim 17, wherein the edit bit is a differing bit of a codeword.

19. The drive of claim 17, wherein the edit bit is a bit within a portion of a sync codeword, the portion having a predetermined polarity, the laser being caused to begin the write operation using the predetermined polarity.

20. The drive of claim 17, wherein the edit bit is a bit in a last line of a modulation-encoded block, the last line providing error correction capability.

21. The drive of claim 20, wherein at least some of the last line is filled with data that allows for data recovery clock stabilization.

22. The drive of claim 20, wherein the edit bit is located to introduce a large random phase discontinuity in the last line.

17. A read/write optical drive comprising:

a laser driver;

a reference signal generator;

a data sector address detector;

a controller, responsive to outputs of the generator and the address detector, for commanding the laser driver to begin a write operation at an edit bit.