IMAGE CODING DEVICE AND IMAGE CODING METHOD

摘要

An image coding device (100) for coding an input image comprises: a picture dividing unit (102) for dividing an input image block to be coded into a plurality of sub-blocks; and an intra-prediction unit (109) for performing an intra-prediction on each of the divided sub-blocks. The intra-prediction unit (109) includes: a determination unit (120) for determining whether or not the size of a sub-block to be predicted is a predetermined size or less; a decision unit (121) for, when it is determined that the size of the sub-block to be predicted is the predetermined size or less, deciding, as prediction mode candidates, m intra-prediction modes that are less than M intra-prediction modes predetermined independently of a block size, where m is a natural number and M is a natural number greater than or equal to 2; and a prediction unit (122) for selecting one intra-prediction mode from among the decided prediction mode candidates and performing an intra-prediction on the sub-block to be predicted using the selected intra-prediction mode.