Discrete / - inverse discrete cosine - transform processor and data processing method

摘要

PURPOSE:To miniaturize the circuit scale and to increase the operating speed of a DCT processor by performing the pre-processing with the addition/ subtraction before a product sum operation in a DCT processing state and then performing the post-processing with the addition/subtraction after a product sum operation in an inverse DCT processing state, respectively. CONSTITUTION:In a DCT processing state, the data inputted/outputted through an input terminal 4 are rearranged by a data rearranging circuit 2 after undergoing the addition/subtraction through a pre-processing part 1 and then sent to a product sum part 3 in the order of low-order bits. The data undergone a product sum operation through the part 3 are transmitted through a post- processing part 7 and outputted through an output terminal 5 as they are. In an inverse DCT processing state, the data inputted through the terminal 4 are rearranged by the circuit 2 after passing through the part 1 and sent to the part 3 in the order of low order bits. The data undergone a sum product operation through the part 3 are sent to the part 7 to undergo the addition/subtraction for calculation of the output data and then outputted through the terminal 5.