DIGITAL DATA PROCESSING UNIT, DIGITAL DATA PROCESSING METHOD, AND DIGITAL DATA PROCESSING PROGRAM

摘要

PROBLEM TO BE SOLVED: To reduce the power consumption in the processing attended by frequency analysis of digital data. SOLUTION: An image coder 1 and an image decoder 2 of one embodiment of this invention can apply arithmetic processing to image data by the 2's compliment form and the code-absolute value form. In applying DCT arithmetic operation to image data, which of the 2's compliment form and the code-absolute value form is used for the processing is selected based on an edge characteristic of the received image data. Since the image data can be processed by an arithmetic method (data form) with lower power consumption, the power consumption at coding or decoding can be reduced.