IMAGE ENCODING DEVICE AND IMAGE ENCODING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an image encoding method that can enhance the compression efficiency of mode information.SOLUTION: An image encoding device has a deriving part for deriving two or more candidates of an intra-prediction mode, a determination part for determining one of the candidates of the intra-prediction mode as an intra-prediction mode used for in-screen prediction, and an adding part for adding an encoded stream with an index for specifying the determined one candidate from the derived candidates of the intra-prediction mode. The deriving part has a first deriving part for deriving a first candidate of the intra-prediction mode from the intra-prediction mode used for the in-screen prediction of each adjacent block which is adjacent to an encoding target block, a determination part for determining whether the number of the derived first candidates is smaller than the number of two or more, and a second deriving part for further deriving a second candidate of the intra-prediction mode when the number of the first candidates is determined to be smaller than the number of two or more.SELECTED DRAWING: Figure 4