IMAGE ENCODING METHOD, IMAGE DECODING METHOD, IMAGE ENCODING DEVICE, IMAGE DECODING DEVICE, AND IMAGE ENCODING/DECODING DEVICE

摘要

Provided is an image encoding method that comprises: an SAO processing step (S141) in which SAO processing is carried out on a Y signal, a Cb signal, and a Cr signal that are included in a block that is a target for processing; a first flag encoding step (S142) in which a first flag (sao_merge_left_flag) is arithmetically encoded, said flag indicating whether an SAO parameter that indicates the content of the abovementioned SAO processing is the same for the block that is a target for processing and a block that is adjacent and to the left of the block that is a target for processing; and an SAO parameter encoding step (S144) in which the SAO parameter for the block that is a target for processing is arithmetically encoded if the SAO parameter for the block that is a target for processing differs from the SAO parameter of the block that is adjacent and to the left of the block that is a target for processing (Step (S143) relates to a case in which the SAO parameters do not differ). In the first flag processing step, the first flag for the Y signal, the Cb signal, and the Cr signal is arithmetically encoded using a single context.