Moving picture coding method and moving picture decoding method for performing inter picture prediction coding and inter picture prediction decoding using previously processed pictures as reference pictures

摘要

A coding control unit (110) and a mode selection unit (109) are included. The coding control unit (110) determines the coding order for a plurality of consecutive B-pictures located between I-pictures and P-pictures so that the B-picture whose temporal distance from two previously coded pictures is farthest in display order is coded by priority, so as to reorder the B-pictures in coding order. When a current block is coded in direct mode, the mode selection unit 109 scales a forward motion vector of a block which is included in a backward reference picture of a current picture and co-located with the current block, so as to generate motion vectors of the current block, if the forward motion vector has been used for coding the co-located block.