Discrete cosine transform device
Discrete cosine transform device
 CN 1,526,103 B
 Filed: 03/20/2002
 Issued: 05/12/2010
 Est. Priority Date: 07/11/2001
 Status: Active Grant
First Claim
1. DCT device, carrying out will be the 2 dimension DCT that image signal transformation that unit takes out from 1 two field picture becomes the DCT coefficient with the piece, it is characterized in that having:
 Signal input part is decomposed into the piece as unit with N pixel * N pixel, is unit with 1 frame, and the N dot image signal of the line direction of each piece of the picture signal that transmits is serially imported successively;
The DCT operational part, by selecting in the abovementioned N dot image signal, a plurality of first matrixes related or the signal selecting part of described a plurality of first matrix and the corresponding set of diagrams image signal of a plurality of second matrixes with each submatrix of N point 1 dimension DCT matrix, and plus and minus calculation portion constitutes, wherein said plus and minus calculation portion comprises and carries out plus and minus calculation so that the longpending totalizer and the subtracter that launches of longpending or described a plurality of first matrix and a plurality of second matrixes of a plurality of first matrixes that are associated with each submatrix of abovementioned N point 1 dimension DCT matrix, and the register of temporarily preserving the plus and minus calculation result, to decompose into a plurality of null matrix and submatrix by the selected picture signal of abovementioned signal selecting part, abovementioned each submatrix is carried out the factor to be decomposed and it to be become by matrix element contain the intermediary matrix of cosine coefficient value and to be worth 1,1 or 0 is the product representation of one or more first matrixes of matrix element, for abovementioned each intermediary matrix being carried out the factor is decomposed so that matrix element by value 1, the product representation of1 or 0 a plurality of second matrixes that constitute is connected the totalizer of abovementioned plus and minus calculation portion with subtracter multistagely, and register is connected so that plus and minus calculation result at different levels supplies to the totalizer and the subtracter of next stage;
The signal efferent will take out in the N point 1 dimension DCT data that the computing of DCT operational part finishes;
WithTransposition portion, 1 dimension DCT data group transposition, the also temporary transient maintenance that will be constituted by the N point 1 dimension DCT data that this signal efferent is supplied with successively;
Abovementioned plus and minus calculation result at the DCT operational part, the N point 1 that finishes as 1 dimension DCT computing is tieed up the DCT data component successively, output to transposition portion via abovementioned signal efferent, and at this place with the row and column transposition of DCT data component and temporary transient the maintenance, in temporary transient N point 1 dimension data that keeps of abovementioned transposition portion, for each row, supply to abovementioned DCT operational part from transposition portion via abovementioned signal input part, locate by 1 dimension data composition at this each row, carry out plus and minus calculation once more and handle, calculate the DCT coefficient of the object that becomes quantification treatment and entropy coding processing.
Chinese PRB Reexamination
Abstract
The purpose is the provision of each of a DCT matrix decomposing method and a DCT device, wherein the device decomposes a onedimensional DCT matrix to make it possible to carrying out a DCT operation only through addition and subtraction. The method is characterized by comprising: a first step of decomposing an NxN onedimensional DCT matrix into a plurality of submatrices and a zero matrix by using the symmetry of a cosine function; a second step of factorizing each of the submatrices to make it possible to express each of the submatrices by the product of an intermediate matrix and one or more first matrices the elements of which are 1, 1 or 0, wherein the intermediate matrix contains a cosine coefficient as a matrix element; and, a third step of repeating a factorization process of each of the intermediate matrices a desired number of times to make it possible to express each of the intermediate matrices by the product of second matrices the elements of which are 1, 1 or 0.
1 Claim

1. DCT device, carrying out will be the 2 dimension DCT that image signal transformation that unit takes out from 1 two field picture becomes the DCT coefficient with the piece, it is characterized in that having:

Signal input part is decomposed into the piece as unit with N pixel * N pixel, is unit with 1 frame, and the N dot image signal of the line direction of each piece of the picture signal that transmits is serially imported successively; The DCT operational part, by selecting in the abovementioned N dot image signal, a plurality of first matrixes related or the signal selecting part of described a plurality of first matrix and the corresponding set of diagrams image signal of a plurality of second matrixes with each submatrix of N point 1 dimension DCT matrix, and plus and minus calculation portion constitutes, wherein said plus and minus calculation portion comprises and carries out plus and minus calculation so that the longpending totalizer and the subtracter that launches of longpending or described a plurality of first matrix and a plurality of second matrixes of a plurality of first matrixes that are associated with each submatrix of abovementioned N point 1 dimension DCT matrix, and the register of temporarily preserving the plus and minus calculation result, to decompose into a plurality of null matrix and submatrix by the selected picture signal of abovementioned signal selecting part, abovementioned each submatrix is carried out the factor to be decomposed and it to be become by matrix element contain the intermediary matrix of cosine coefficient value and to be worth 1,1 or 0 is the product representation of one or more first matrixes of matrix element, for abovementioned each intermediary matrix being carried out the factor is decomposed so that matrix element by value 1, the product representation of1 or 0 a plurality of second matrixes that constitute is connected the totalizer of abovementioned plus and minus calculation portion with subtracter multistagely, and register is connected so that plus and minus calculation result at different levels supplies to the totalizer and the subtracter of next stage; The signal efferent will take out in the N point 1 dimension DCT data that the computing of DCT operational part finishes;
WithTransposition portion, 1 dimension DCT data group transposition, the also temporary transient maintenance that will be constituted by the N point 1 dimension DCT data that this signal efferent is supplied with successively; Abovementioned plus and minus calculation result at the DCT operational part, the N point 1 that finishes as 1 dimension DCT computing is tieed up the DCT data component successively, output to transposition portion via abovementioned signal efferent, and at this place with the row and column transposition of DCT data component and temporary transient the maintenance, in temporary transient N point 1 dimension data that keeps of abovementioned transposition portion, for each row, supply to abovementioned DCT operational part from transposition portion via abovementioned signal input part, locate by 1 dimension data composition at this each row, carry out plus and minus calculation once more and handle, calculate the DCT coefficient of the object that becomes quantification treatment and entropy coding processing.

Specification(s)