Patent ID: 7706622

Claim:
An image coding apparatus for performing a coding process, the image coding apparatus comprising: a mode selection unit arranged to select a definition type of an input image; an input unit arranged to input image data in accordance with an output of the mode selection unit; an image size determination unit arranged to determine an image size of the image data input by the input unit in accordance with the output of the mode selection unit; a plurality of orthogonal transform units arranged to perform an the image data input by the input unit image data, wherein the plurality of the orthogonal transform units perform the orthogonal-transform corresponding to each of different block sizes; a block size determination unit arranged to determine a block size of the image data input by the input unit in accordance with the image size determined by the image size determination unit; and a block construction unit arranged to divide the image data input by the input unit into blocks of the block size determined by the block size determination unit, to select one of the plurality of orthogonal transform units in accordance with the block size determined by the block size determination unit, and to supply image data divided into the blocks to the selected orthogonal transform unit.