MOTION VECTOR CODING AND DECODING METHODS

摘要

A coding apparatus includes a motion vector coding unit that codes an inputted motion vector. A motion vector for each current block is coded based on a difference between the motion vector and a predicted vector obtained from motion vectors of coded neighboring blocks. The predicted vector is generated by one of the following methods: motion vectors referring to the same picture are selected from among the motion vectors for the neighboring blocks; motion vectors of respective neighboring blocks are ordered in a, predetermined order, and the motion vectors of the same order rank are selected from the ordered motion vectors; and the predicted vector of a second motion vector of the current block is the first motion vector, and if the second motion vector and the first motion vector refer to different pictures, the first motion vector is scaled according to the temporal distance between the pictures.