| 摘要 |
PROBLEM TO BE SOLVED: To reduce an overall code amount by further compressing coding information in an image coding system using hierarchical coding.SOLUTION: A first inter-prediction information derivation unit derives the candidate of first inter-prediction information from the inter-prediction information of a block spatially close to a decoding target block in the same picture as the decoding target block. A second inter-prediction information derivation unit derives the candidate of second inter-prediction information from the inter-prediction information of a block in a picture in a reference hierarchy or a block in a picture which is included in the same hierarchy as the decoding target block but temporally different therefrom. The second inter-prediction information derivation unit can select a mode of switching on a sequence-by-sequence basis, or a mode of switching on a picture-by-picture or a slice-by-slice basis, whether to use the picture in the reference hierarchy or the temporally different picture, as a reference picture. |
