Patent ID: 9654773
Date: 2017-05-16
CPC Classifications: H04N

Claim:
1. An image decoding device that carries out a decoding process on a coded data obtained by performing a block based coding process on an image, said image decoding device comprising: a coded data decoder to decode the coded data to acquire compressed data of a difference image and a coding mode associated with each of coding blocks, the coding mode indicating a prediction mode and prediction blocks in each of the coding blocks; a prediction image generator to carry out a prediction process for each of the coding blocks according to the coding mode to generate a prediction image of each of coding blocks; a decoded image generator to add a decompressed difference image to the prediction image for each of the blocks to generate a decoded image; and an image distortion remover to carry out a filtering process on the decoded image to remove a block distortion occurring at a boundary between adjacent prediction blocks of the decoded image, wherein the image distortion remover derives a parameter specifying filtering strength according to a set of conditions including whether the coding mode corresponding to at least one of the adjacent prediction blocks to which the filtering process is to be applied is intra prediction mode, and a value of the parameter is used in a process of selecting from different filtering processes.