Patent Document ID: 20130329804
Application ID: 13966527
Patent Status: 0

Claim One:
1. A picture coding method for coding a moving picture, comprising: a neighboring block specification step of specifying a neighboring block which is located in the neighborhood of the current block and has already been coded; a judgment step of judging whether or not the neighboring block has been coded using a motion vector of another block; a prediction step of deriving a predictive motion vector of the current block using a motion vector calculated from the motion vector of the other block as a motion vector of the neighboring block, when it is judged in the judgment step that the neighboring block has been coded using the motion vector of the other block; a motion vector coding step of coding a difference value between the motion vector of the current block and the predictive motion vector; a motion compensation step of generating a motion compensated picture using the motion vector of the current block and a reference picture corresponding to the motion vector of the current block; and a coding step of coding a prediction error between the current block and the motion compensated picture, wherein in a case where the other block has two motion vectors, the predictive motion vector is derived in temporally forward direction and temporally backward direction separately in the prediction step, and the motion vector of the current block is coded in temporally forward direction and temporally backward direction separately in the motion vector coding step.