IMAGE DECODING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an image decoding method that can apply proper decoding to a coded pixel value signal and a coded shape signal that are subjected to efficient coding through referencing to proper pixel value and shape signals and efficiently and properly decode a coded shape signal while relieving the referencing load without much deteriorating prediction accuracy. SOLUTION: The image decoding method employs a decoder 303 that decodes the coded pixel value signal and a decoder 312 that decodes the coded shape signal and decides a reference method for decoding the shape signal by discriminating by each frame which of a preceding time decoded shape signal and a succeeding time decoded shape signal is to be referenced and discriminating whether or not the decoded shape signal is to be referenced by each block.