Encoding and decoding system in an optical disk storage device

• US 6,832,042 B1
• Filed: 11/15/2000
• Issued: 12/14/2004
• Est. Priority Date: 05/24/2000
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: Acer America Incorporated (Acer, Inc.)
• Inventors: Shieh, Jia-Horng
• Primary Examiner(s): TRAN, THAI Q
• Application Number:
  US09/711,922
• Time in Patent Office: 1,490 Days
• Field of Search: H04/N.5781, 386/45, 386/125, 386/126, 386/40, 386/21, 386/113, 386/116, 386/124, 360/32, 360/40, 360/48, 360/53, 714/746, 714/752, 714/756, 714/763, 714/764, 714/768, 714/769, 714/770, 714/771, 714/773, 714/781, 714/784, 714/785, 714/793
• US Class Current: 386/264
• CPC Class Codes: G11B 20/10009 Improvement or modification of read or write signals
• CPC Class Codes: G11B 20/18 Error detection or correction; Testing , e.g. of drop-outs
• CPC Class Codes: H04N 5/85 on discs or drums
• CPC Class Codes: H04N 9/7921 for more than one processing mode
• CPC Class Codes: H04N 9/8042 involving data reduction

Abstract

An encoding/decoding system in an optical disk storage device for performing compact disc/digital video disk (CD/DVD) encoding/decoding of data. The encoding/decoding system includes address mappers for C1, C2, CD P/Q, and DVD inner/outer codes respectively and a shareable Reel-Solomon (RS) encoder/decoder. The shareable RS encoder/decoder is capable of selectively being coupled to either one of the address mappers. When the encoding/decoding system is encoding, the shareable RS encoder/decoder employs a generation polynomial of RS code to generate a parity code of 2T symbols and output a codeword of N symbols, wherein the values of N and 2T are associated with the selected address mapper. When the encoding/decoding system is decoding, the shareable RS encoder/decoder generates a number of syndromes, S_k (k=0˜15 and k is a positive integer), an error-erasure locator polynomial and an error-erasure evaluator polynomial for obtaining an error value to complete the error correction, wherein a syndrome S_k is set to zero if k is greater than or equal to 2T.

Claims

1. An encoding/decoding system in an optical disk storage device, for performing compact disc/digital video disk (CD/DVD) encoding/decoding of data, the data stored in a data buffer, the encoding/decoding system comprising:

a C1 address mapper for accessing to the data buffer according to access sequence stored in the C1 address mapper;

a C2 address mapper for accessing to the data buffer according to access sequence stored in the C2 address mapper;

a CD P/Q address mapper for accessing to the data buffer according to access sequence stored in the CD P/Q address mapper;

a DVD inner/outer address mapper for accessing to the data buffer according to access sequence stored in the DVD inner/outer address mapper; and

a shareable Reel-Solomon (RS) encoder/decoder capable of selectively being coupled to either one of the C1 address mapper, the C2 address mapper, the CD P/Q address mapper, or the DVD inner/outer address mapper;

wherein the shareable Reel-Solomon (RS) encoder/decoder employs a generation polynomial of RS code when the encoding/decoding system is encoding, the generation polynomial of RS code is for generating a first codeword of N symbols including a parity code of 2T symbols, where the values of N and 2T are associated with the selected address mapper;

wherein the generation polynomial G(x) is;

G(x)=Π

<sub>k=0˜

(2T−

1)</sub>(x+α

^k), where α

is an element of a finite field GF(2⁸) and is a root of a primitive polynomial P(x);

2. An encoding/decoding system according to claim 1, wherein:

when the encoding/decoding system is decoding, the shareable RS encoder/decoder receives a second codeword of N symbols including a parity code of 2T symbols and generates a plurality of syndromes, S_k, where k=0˜

15 and k is a positive integer, an error-erasure locator polynomial and an error-erasure evaluator polynomial for obtaining an error value to complete the error correction, wherein;

a syndrome S_k is set to zero if k is greater than or equal to 2T and the syndromes are obtained from;

$S_k=\underset{i=0~N-1}{\sum <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(r_i<br><br>{\mathrm{\alpha <br><br>}}^{\mathrm{ik}}\right)<br><br>\text{\hspace{1em}<br><br>}<br><br>\mathrm{for}<br><br>\text{\hspace{1em}<br><br>}<br><br>k=0~2<br><br>T-1,$

where r_i for i=0˜

N−

1 represents the N symbols of the codeword.

3. An encoding/decoding system according to claim 1, wherein the shareable Reel-Solomon (RS) encoder/decoder comprises:

an error correction code/syndrome (ECC/syndrome) generator, wherein the error correction code/syndrome (ECC/syndrome) generator is operative;

to employ the generation polynomial to generate the parity code and to output the first codeword when the encoding/decoding system is encoding, or

to output the syndromes S_k, where k=0˜

15 and k is a positive integer, when the encoding/decoding system is decoding;

an error-erasure locator/evaluator polynomial generator for generating the error-erasure locator polynomial and the error-erasure evaluator polynomial;

a Forney syndrome generator, coupled to the ECC/syndrome generator, for generating an erasure location polynomial and a Forney'"'"'s modified syndrome polynomial, the Forney syndrome generator being for generating initialization values required by the error-erasure locator/evaluator polynomial generator;

a Chien search unit for obtaining a root of the error-erasure locator polynomial for finding an error location and an error value;

a first switch for selecting either the ECC/syndrome generator'"'"'s output or the Chien search unit'"'"'s output as the shareable RS encoder/decoder'"'"'s output; and

a second switch for selecting either the ECC/syndrome generator'"'"'s output or the Forney syndrome generator'"'"'s output as the error-erasure locator/evaluator polynomial generator'"'"'s input.

4. An encoding/decoding system according to claim 3, wherein the shareable RS encoder/decoder further comprises:

an inverter, coupled to an input terminal of the shareable RS encoder/decoder, for inverting input data and outputting the inverted input data; and

a third switch for selecting either coupling the input terminal of the shareable RS encoder/decoder to the ECC/syndrome generator or delivering the inverted input data to the ECC/syndrome generator.

5. An encoding/decoding system according to claim 3, wherein an interleaving process is performed when the C1 address mapper or the C2 address mapper accesses to the data buffer for encoding and a deinterleaving process is performed when the C1 address mapper or the C2 address mapper accesses to the data buffer for decoding.

6. An encoding/decoding system according to claim 3, wherein the encoding/decoding system further comprises a burst cutting area (BCA) ECC address mapper for accessing to the data buffer according to access sequence in the BCA ECC address mapper.

7. An encoding/decoding system according to claim 6, wherein:

the value of T is equal to two when the shareable RS encoder/decoder processes output from the C1 address mapper, the C2 address mapper, or the BCA ECC address mapper;

the value of T is equal to one when the shareable RS encoder/decoder processes output from the CD P/Q address mapper;

or

the value of T is equal to eight for performing outer encoding/decoding or is equal to five for performing inner encoding/decoding respectively when the shareable RS encoder/decoder processes output from the DVD inner/outer address mapper.

8. An encoding/decoding system in an optical disk storage device, for performing compact disc/digital video disk (CD/DVD) encoding/decoding of data, the data stored in a data buffer, the encoding/decoding system comprising:

a C1 address mapper for accessing to the data buffer according to access sequence stored in the C1 address mapper;

a C2 address mapper for accessing to the data buffer according to access sequence stored in the C2 address mapper;

a CD P/Q address mapper for accessing to the data buffer according to access sequence stored in the CD P/Q address mapper;

a DVD inner/outer address mapper for accessing to the data buffer according to access sequence stored in the DVD inner/outer address mapper; and

a shareable Reel-Solomon (RS) encoder/decoder capable of selectively being coupled to either one of the C1 address mapper, the C2 address mapper, the CD P/Q address mapper, or the DVD inner/outer address mapper;

wherein when the encoding/decoding system is decoding, the shareable RS encoder/decoder receives a first codeword of N symbols including a parity code of 2T symbols, where the values of N and 2T are associated with the selected address mapper, and generates a plurality of syndromes S_k, where k=0˜

15 and k is a positive integer, an error-erasure locator polynomial and an error-erasure evaluator polynomial for obtaining an error value to complete the error correction, wherein;

a syndrome S_k is set to zero if k is greater than or equal to 2T, the values of N and 2T are associated with the selected address mapper; and

the syndromes S_k are obtained from;

$S_k=\underset{i=0~N-1}{\sum <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>\left(r_i<br><br>{\mathrm{\alpha <br><br>}}^{\mathrm{ik}}\right)<br><br>\text{\hspace{1em}<br><br>}<br><br>\mathrm{for}<br><br>\text{\hspace{1em}<br><br>}<br><br>k=0~2<br><br>T-1,$

where r_i for i=0˜

N−

1 represents the N symbols of the codeword and

α

is an element of a finite field GF(2⁸) and is a root of a primitive polynomial P(x);

9. An encoding/decoding system according to claim 8, wherein the shareable RS encoder/decoder employs an generation polynomial of RS code when the encoding/decoding system is encoding, the generation polynomial is for generating a second codeword of N symbols including a parity code of 2T symbols, wherein the generation polynomial G(x) is:

10. An encoding/decoding system in an optical disk storage device, for performing compact disc/digital video disk (CD/DVD) encoding/decoding of data, the data stored in a data buffer, the encoding/decoding system comprising:

a C1 address mapper for accessing to the data buffer according to access sequence stored in the C1 address mapper;

a C2 address mapper for accessing to the data buffer according to access sequence stored in the C2 address mapper;

a CD P/Q address mapper for accessing to the data buffer according to access sequence stored in the CD P/Q address mapper;

a DVD inner/outer address mapper for accessing to the data buffer according to access sequence stored in the DVD inner/outer address mapper; and

a shareable Reel-Solomon (RS) encoder/decoder capable of selectively being coupled to either one of the C1 address mapper, the C2 address mapper, the CD P/Q address mapper, or the DVD inner/outer address mapper, the shareable Reel-Solomon (RS) encoder/decoder comprising;

an error correction code/syndrome (ECC/syndrome) generator, wherein the ECC/syndrome generator is operative;

to employ the generation polynomial to generate a parity code and to output a first codeword when the encoding/decoding system is encoding, or

to output a plurality of syndromes S_k, where k=0˜

15 and k is a positive integer, when the encoding/decoding system is decoding;

an error-erasure locator/evaluator polynomial generator for generating an error-erasure locator polynomial and an error-erasure evaluator polynomial;

a Forney syndrome generator, coupled to the ECC/syndrome generator, for generating an erasure location polynomial and a Forney'"'"'s modified syndrome polynomial, the Forney syndrome generator being for generating initialization values required by the error-erasure locator/evaluator polynomial generator;

a Chien search unit for obtaining a root of the error-erasure locator polynomial for finding an error location and an error value;

a first switch, coupled between an output terminal of the shareable RS encoder/decoder and;

the ECC/syndrome generator when the encoding/decoding system is encoding, or

the Chien switch unit when the encoding/decoding system is decoding; and

a second switch, coupled between the error-erasure locator/evaluator polynomial generator and;

the Forney syndrome generator when there is an erasure, or

the CRC/syndrome generator otherwise;

wherein the generation polynomial G(x) is;

11. An encoding/decoding system according to claim 10, wherein the shareable RS encoder/decoder further comprises:

an inverter, coupled to an input terminal of the shareable RS encoder/decoder, for inverting input data and outputting the inverted input data; and

a third switch for selecting either coupling the input terminal of the shareable RS encoder/decoder to the ECC/syndrome generator or delivering the inverted input data to the ECC/syndrome generator.

12. An encoding/decoding system according to claim 11, wherein an interleaving process is performed when the C1 address mapper or the C2 address mapper accesses to the data buffer for encoding and a deinterleaving process is performed when the C1 address mapper or the C2 address mapper accesses to the data buffer for decoding.

13. An encoding/decoding system according to claim 11, wherein the encoding/decoding system further comprises a burst cutting area (BCA) ECC address mapper for accessing to the data buffer according to access sequence in the BCA ECC address mapper.

14. An encoding/decoding system according to claim 11, wherein:

the value of T is equal to two when the shareable RS encoder/decoder processes output from the C1 address mapper, the C2 address mapper, or the BCA ECC address mapper;

the value of T is equal to one when the shareable RS encoder/decoder processes output from the CD P/Q address mapper;

or

the value of T is equal to eight for performing outer encoding/decoding or is equal to five for performing inner encoding/decoding respectively when the shareable RS encoder/decoder processes output from the DVD inner/outer address mapper.

15. A shareable Reel-Solomon (RS) encoder/decoder capable of selectively being coupled to either one of a C1 address mapper, a C2 address mapper, a CD P/Q address mapper, or a DVD inner/outer address mapper, the shareable RS encoder/decoder comprising:

an error correction code/syndrome (ECC/syndrome) generator, wherein the ECC/syndrome generator is operative;

to employ a generation polynomial of RS code to generate a parity code of 2T symbols and to output a codeword of N symbols, where the values of 2T and N are associated with the selected address mapper, when the shareable RS encoder/decoder is encoding, or

to generate a plurality of syndromes S_k, where k=0˜

15 and k is a positive integer and a syndrome S_k is set to zero if k is greater than or equal to 2T, when the shareable RS encoder/decoder is decoding;

an error-erasure locator/evaluator polynomial generator for generating the error-erasure locator polynomial and the error-erasure evaluator polynomial;

a Forney syndrome generator, coupled to the ECC/syndrome generator, for generating an erasure location polynomial and a Forney'"'"'s modified syndrome polynomial, the Forney syndrome generator being for generating initialization values required by the error-erasure locator/evaluator polynomial generator;

a Chien search unit for obtaining a root of the error-erasure locator polynomial for finding an error location and an error value;

a first switch, coupled between an output terminal of the shareable RS encoder/decoder and;

the ECC/syndrome generator when the shareable RS encoder/decoder is encoding, or

the Chien switch unit when the shareable RS encoder/decoder is decoding; and

a second switch, coupled between the error-erasure locator/evaluator polynomial generator and;

the Forney syndrome generator when there is an erasure, or

the CRC/syndrome generator otherwise;

wherein the generation polynomial G(x) is;

16. A shareable RS encoder/decoder according to claim 15, further comprising:

an inverter, coupled to an input terminal of the shareable RS encoder/decoder, for inverting input data and outputting the inverted input data; and

a third switch for selecting either coupling the input terminal of the shareable RS encoder/decoder to the ECC/syndrome generator or delivering the inverted input data to the ECC/syndrome generator.

17. A shareable RS encoder/decoder according to claim 15, wherein the shareable RS encoder/decoder is capable of selectively being coupled to a burst cutting area (BCA) ECC address mapper further.

18. A shareable RS encoder/decoder according to claim 15, wherein:

the value of T is equal to two when the shareable RS encoder/decoder processes output from the C1 address mapper, the C2 address mapper, or the BCA ECC address mapper;

the value of T is equal to one when the shareable RS encoder/decoder processes output from the CD P/Q address mapper;

or

the value of T is equal to eight for performing outer encoding/decoding or is equal to five for performing inner encoding/decoding respectively when the shareable RS encoder/decoder processes output from the DVD inner/outer address mapper.

19. An encoding/decoding system in an optical disk storage device, for performing compact disc/digital video disk (CD/DVD) encoding/decoding of data, the data stored in a data buffer, the encoding/decoding system comprising:

a CD address mapper for accessing to the data buffer according to access sequence stored in the CD address mapper;

a DVD inner/outer address mapper for accessing to the data buffer according to access sequence stored in the DVD inner/outer address mapper; and

a shareable Reel-Solomon (RS) encoder/decoder capable of selectively being coupled to either the CD address mapper or the DVD inner/outer address mapper;

wherein the shareable Reel-Solomon (RS) encoder/decoder employs a generation polynomial of RS code when the encoding/decoding system is encoding, the generation polynomial is for generating a first codeword of N symbols including a parity code of 2T symbols, where the values of N and 2T are associated with the selected address mapper; and

wherein the generation polynomial G(x) is;

G(x)=Π

<sub>k=0˜

(2T−

1)</sub>(x+α

^k), where α

is an element of a finite field GF(2⁸) and is a root of a primitive polynomial P(x);

20. An encoding/decoding system according to claim 19, wherein the CD address mapper comprises:

a C1 address mapper for accessing to the data buffer according to access sequence stored in the C1 address mapper;

a C2 address mapper for accessing to the data buffer according to access sequence stored in the C2 address mapper; and

a CD P/Q address mapper for accessing to the data buffer according to access sequence stored in the CD P/Q address mapper.