Run manner null of multiplication operation retrenchment possible two dimensional dispersion cosine conversion and its adverse change

摘要

PROBLEM TO BE SOLVED: To obtain a method for executing discrete cosine transformation(DCT) and its inverse transformation(IDCT) capable of reducing multiplication operation by preparing continued 1st and 2nd cycle one-dimensional(1D) DCT operatations provided with respective steps for controlling an output unit and receiving a two-dimensional(2D) transformation data from a multiplication operation unit.;SOLUTION: A control unit 6 controls a data register unit 4, successively outputs a standardized 1D transformation data from another direction to a butterfly operation unit 2 through a reading port and the unit 2 executes the 1st step operation of a DCT quick calculation method for the 2nd cycle 1D DCT operation. Then 2nd to 5th step operations of the DCT quick calculation method for the 2nd cycle 1D DCT operation are executed by the same format as the 2nd to 5th step operations of the DCT quick calculation method for the 1st 1D DCT operation. Consequently corresponding operations in the DCT/IDCT quick operation method can be omitted, the number of multiplication operations in 2D DCT/IDCT processing can be reduced and a higher processing speed can be realized.;COPYRIGHT: (C)2000,JPO