Image coding method and decoding method and device thereof
Image coding method and decoding method and device thereof
 CN 100,527,839 C
 Filed: 03/27/2003
 Issued: 08/12/2009
 Est. Priority Date: 04/15/2002
 Status: Active Grant
First Claim
1. coding/decoding method, being used for the piece is that unit decodes to coded data, and this coded data is encoded to the piece image by the coefficient that the piece image transform is become the representation space frequency content and is obtained, and this method comprises:
 Obtain step, by with reference to before be stored in expression in the memory and be arranged in the information of sum of nonzero coefficient that the information of the sum of the nonzero coefficient of the upper block of decoded current block top and the expression that is stored in abovementioned memory before is arranged in the left side block in abovementioned current block left side, obtain the sum of the nonzero coefficient in the abovementioned upper block and the sum of the nonzero coefficient in the abovementioned left side block, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition;
Determining step according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is obtained and the abovementioned left side block that obtained, is determined the predicted value with the sum of the nonzero coefficient in the decoded abovementioned current block;
Select step,, select the variable length code table according to determined predicted value;
Decoding step by using selected variable length code table, is decoded to the coded data that the sum by the nonzero coefficient in the abovementioned current block of encoding obtains, to obtain the sum of the nonzero coefficient in the decoded abovementioned current block;
AndStoring step is stored in the sum of abovementioned decoded nonzero coefficient in the abovementioned memory, as the information of the sum of the nonzero coefficient in the abovementioned current block of expression.
Litigations
Chinese PRB Reexamination
Abstract
The present ivention provides Image coding method and decoding method and device thereof, capable of encoding the number of nonzero coefficients included in a block after applying orthogonal transformation with high efficiency for all times independently of the character of a target image. The present iventive decoding method includes: a acquiring step for acquiring the number of coefficients other than 0 contained in a upper block and the number of coefficients other than 0 contained in a left block by referinf to the information of the numbers of coefficients other than 0 contained in coded block located above the current block to be decoded, and the information of the numbers of coefficients other than 0 contained in coded blocks located on the left of the current block to be decoded; a determinating step for determinating a predictive value of the number of coefficients other than 0 in a current block to be decoded; a selecting step for selecting variable length coding tables; a decoding step; and a storing step.
16 Claims

1. coding/decoding method, being used for the piece is that unit decodes to coded data, and this coded data is encoded to the piece image by the coefficient that the piece image transform is become the representation space frequency content and is obtained, and this method comprises:

Obtain step, by with reference to before be stored in expression in the memory and be arranged in the information of sum of nonzero coefficient that the information of the sum of the nonzero coefficient of the upper block of decoded current block top and the expression that is stored in abovementioned memory before is arranged in the left side block in abovementioned current block left side, obtain the sum of the nonzero coefficient in the abovementioned upper block and the sum of the nonzero coefficient in the abovementioned left side block, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; Determining step according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is obtained and the abovementioned left side block that obtained, is determined the predicted value with the sum of the nonzero coefficient in the decoded abovementioned current block; Select step,, select the variable length code table according to determined predicted value; Decoding step by using selected variable length code table, is decoded to the coded data that the sum by the nonzero coefficient in the abovementioned current block of encoding obtains, to obtain the sum of the nonzero coefficient in the decoded abovementioned current block;
AndStoring step is stored in the sum of abovementioned decoded nonzero coefficient in the abovementioned memory, as the information of the sum of the nonzero coefficient in the abovementioned current block of expression.


2. coding/decoding method, being used for the piece is that unit decodes to coded data, and this coded data is encoded to the piece image by the coefficient that the piece image transform is become the representation space frequency content and is obtained, and this method comprises:

Derive step, be arranged in the information of the level value of the conversion coefficient of the upper block of decoded current block top, derive the sum of the nonzero coefficient of abovementioned upper block according to being stored in expression in the memory before, and according to be stored in before expression in the abovementioned memory be arranged in abovementioned current block left side left side block conversion coefficient level value information, derive the sum of the nonzero coefficient of abovementioned left side block, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; Determining step according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is derived and the abovementioned left side block of being derived, is determined the predicted value with the sum of the nonzero coefficient in the decoded abovementioned current block; Select step,, select the variable length code table according to determined predicted value; Decoding step, by using selected variable length code table, abovementioned coded data is decoded, to obtain the sum of the nonzero coefficient in the decoded abovementioned current block, and abovementioned coded data decoded, to obtain the level value of the conversion coefficient in the decoded abovementioned current block;
AndStoring step is stored in abovementioned decoded level value in the abovementioned memory, as the information of the level value of representing the conversion coefficient in the abovementioned current block.


3. according to the coding/decoding method of claim 1,
The abovementioned information of representing the sum of the nonzero coefficient in the abovementioned current block is stored in the abovementioned memory, up to the lower block that is arranged in abovementioned current block below be positioned at nonzero coefficient total decoded of the right side block on abovementioned current block right side.

4. according to the coding/decoding method of claim 2,
Wherein, represent that the abovementioned information of the level value of the conversion coefficient in the abovementioned current block is stored in the abovementioned memory, up to the lower block that is arranged in abovementioned current block below be positioned at nonzero coefficient total decoded of the right side block on abovementioned current block right side.

5. coding method, being used for the piece is that unit encodes to the conversion coefficient of piece, and this conversion coefficient is by becoming the coefficient of representation space frequency content to obtain the piece image transform, and this method comprises:

Derive step, derive the sum with the nonzero coefficient in the current block that is encoded, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; Storing step is stored in the sum of the nonzero coefficient of being derived in the memory, as the information of the sum of the nonzero coefficient in the abovementioned current block of expression; Obtain step, by with reference to before be stored in the information of sum that expression in the abovementioned memory is arranged in the nonzero coefficient of the information of sum of nonzero coefficient of upper block of abovementioned current block top and the left side block that the expression that is stored in abovementioned memory before is arranged in abovementioned current block left side, obtain the sum of the nonzero coefficient in the abovementioned upper block and the sum of the nonzero coefficient in the abovementioned left side block; Determining step is according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is obtained and the abovementioned left side block that obtained, the predicted value of the sum of the nonzero coefficient in the abovementioned current block of determining to be encoded; Select step,, select the variable length code table according to determined predicted value;
AndCoding step by using selected variable length code table, is encoded to the sum of the nonzero coefficient in the abovementioned current block.


6. coding method, being used for the piece is that unit encodes to the conversion coefficient of piece, and this conversion coefficient is by becoming the coefficient of representation space frequency content to obtain the piece image transform, and this method comprises:

Derive step, derive the sum with the nonzero coefficient in the current block that is encoded, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; Storing step is stored in the level value of the conversion coefficient in the abovementioned current block in the memory, as the information of the level value of the conversion coefficient in the abovementioned current block of expression; Derive step, according to be stored in before expression in the abovementioned memory be arranged in abovementioned current block top upper block conversion coefficient level value information, derive the sum of the nonzero coefficient of abovementioned upper block, and according to be stored in before expression in the abovementioned memory be arranged in abovementioned current block left side left side block conversion coefficient level value information, derive the sum of the nonzero coefficient of abovementioned left side block; Determining step is according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is derived and the abovementioned left side block of being derived, the predicted value of the sum of the nonzero coefficient in the abovementioned current block of determining to be encoded; Select step,, select the variable length code table according to determined predicted value;
AndCoding step by using selected variable length code table, is encoded to the sum of the nonzero coefficient in the abovementioned current block.


7. according to the coding method of claim 5,
Wherein, represent that the abovementioned information of the sum of the nonzero coefficient in the abovementioned current block is stored in the abovementioned memory, be encoded up to the lower block that is arranged in abovementioned current block below and the sum of nonzero coefficient that is positioned at the right side block on abovementioned current block right side.

8. according to the coding method of claim 6,
Wherein, represent that the abovementioned information of the level value of the conversion coefficient in the abovementioned current block is stored in the abovementioned memory, be encoded up to the lower block that is arranged in abovementioned current block below and the sum of nonzero coefficient that is positioned at the right side block on abovementioned current block right side.

9. decoding device, being used for the piece is that unit decodes to coded data, and this coded data is encoded to the piece image by the coefficient that the piece image transform is become the representation space frequency content and is obtained, and this equipment comprises:

Memory; Reading unit, by with reference to before be stored in expression in the abovementioned memory and be arranged in the information of sum of nonzero coefficient that the information of the sum of the nonzero coefficient of the upper block of decoded current block top and the expression that is stored in abovementioned memory before is arranged in the left side block in abovementioned current block left side, obtain the sum of the nonzero coefficient in the abovementioned upper block and the sum of the nonzero coefficient in the abovementioned left side block, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; The predicted value determining unit according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is obtained and the abovementioned left side block that obtained, is determined the predicted value with the sum of the nonzero coefficient in the decoded abovementioned current block; The coding schedule selected cell according to determined predicted value, is selected the variable length code table; Decoding unit by using selected variable length code table, is decoded to the coded data that the sum by the nonzero coefficient in the abovementioned current block of encoding obtains, to obtain the sum of the nonzero coefficient in the decoded abovementioned current block;
AndMemory cell is stored in the sum of abovementioned decoded nonzero coefficient in the abovementioned memory, as the information of the sum of the nonzero coefficient in the abovementioned current block of expression.


10. decoding device, being used for the piece is that unit decodes to coded data, and this coded data is encoded to the piece image by the coefficient that the piece image transform is become the representation space frequency content and is obtained, and this equipment comprises:

Memory; Reading unit, be arranged in the information of the level value of the conversion coefficient of the upper block of decoded current block top, derive the sum of the nonzero coefficient of abovementioned upper block according to being stored in expression in the abovementioned memory before, and according to be stored in before expression in the abovementioned memory be arranged in abovementioned current block left side left side block conversion coefficient level value information, derive the sum of the nonzero coefficient of abovementioned left side block, wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; The predicted value determining unit according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is derived and the abovementioned left side block of being derived, is determined the predicted value with the sum of the nonzero coefficient in the decoded abovementioned current block; The coding schedule selected cell according to determined predicted value, is selected the variable length code table; First decoding unit by using selected variable length code table, is decoded to abovementioned coded data, to obtain the sum of the nonzero coefficient in the decoded abovementioned current block; Second decoding unit is decoded to abovementioned coded data, to obtain the level value of the conversion coefficient in the decoded abovementioned current block;
AndMemory cell is stored in abovementioned decoded level value in the abovementioned memory, as the information of the level value of representing the conversion coefficient in the abovementioned current block.


11. according to the decoding device of claim 9,
Wherein, the abovementioned information of representing the sum of the nonzero coefficient in the abovementioned current block is stored in the abovementioned memory, will be arranged in the lower block of abovementioned current block below and be positioned at total number decoder of nonzero coefficient of the right side block on abovementioned current block right side up to abovementioned decoding unit.

12. according to the decoding device of claim 10,
Wherein, the abovementioned information of representing the level value of the conversion coefficient in the decoded abovementioned current block is stored in the abovementioned memory, will be arranged in the lower block of abovementioned current block below and be positioned at total number decoder of nonzero coefficient of the right side block on abovementioned current block right side up to abovementioned first decoding unit.

13. an encoding device, being used for the piece is that unit encodes to the conversion coefficient of piece, and this conversion coefficient is by becoming the coefficient of representation space frequency content to obtain the piece image transform, and this equipment comprises:

Memory; Computing unit is derived the sum with the nonzero coefficient in the current block that is encoded, and wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; Memory cell is stored in the sum of the nonzero coefficient of being derived in the abovementioned memory, as the information of the sum of the nonzero coefficient in the abovementioned current block of expression; Reading unit, by with reference to before be stored in the information of sum that expression in the abovementioned memory is arranged in the nonzero coefficient of the information of sum of nonzero coefficient of upper block of abovementioned current block top and the left side block that the expression that is stored in abovementioned memory before is arranged in abovementioned current block left side, obtain the sum of the nonzero coefficient in the abovementioned upper block and the sum of the nonzero coefficient in the abovementioned left side block; The predicted value determining unit is according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is obtained and the abovementioned left side block that obtained, the predicted value of the sum of the nonzero coefficient in the abovementioned current block of determining to be encoded; The coding schedule selected cell according to determined predicted value, is selected the variable length code table;
AndCoding unit by using selected variable length code table, is encoded to the sum of the nonzero coefficient in the abovementioned current block.


14. an encoding device, being used for the piece is that unit encodes to the conversion coefficient of piece, and this conversion coefficient is by becoming the coefficient of representation space frequency content to obtain the piece image transform, and this equipment comprises:

Memory; Computing unit is derived the sum with the nonzero coefficient in the current block that is encoded, and wherein each nonzero coefficient is for having the conversion coefficient of " 0 " level value in addition; Memory cell is stored in the level value of conversion coefficient in the abovementioned memory, as the information of the level value of the conversion coefficient in the abovementioned current block of expression; Reading unit, according to be stored in before expression in the abovementioned memory be arranged in abovementioned current block top upper block conversion coefficient level value information, derive the sum of the nonzero coefficient of abovementioned upper block, and according to be stored in before expression in the abovementioned memory be arranged in abovementioned current block left side left side block conversion coefficient level value information, derive the sum of the nonzero coefficient of abovementioned left side block; The predicted value determining unit is according to the sum of the nonzero coefficient in the sum of the nonzero coefficient in the abovementioned upper block that is derived and the abovementioned left side block of being derived, the predicted value of the sum of the nonzero coefficient in the abovementioned current block of determining to be encoded; The coding schedule selected cell according to determined predicted value, is selected the variable length code table;
AndCoding unit by using selected variable length code table, is encoded to the sum of the nonzero coefficient in the abovementioned current block.


15. according to the encoding device of claim 13,
Wherein, the abovementioned information of representing the sum of the nonzero coefficient in the abovementioned current block is stored in the abovementioned memory, will be arranged in the lower block of abovementioned current block below and be positioned at total number encoder of nonzero coefficient of the right side block on abovementioned current block right side up to abovementioned coding unit.

16. according to the encoding device of claim 14,
Wherein, the abovementioned information of representing the level value of the conversion coefficient in the abovementioned current block is stored in the abovementioned memory, will be arranged in the lower block of abovementioned current block below and be positioned at total number encoder of nonzero coefficient of the right side block on abovementioned current block right side up to abovementioned coding unit.
Specification(s)