Patent ID: 8428136

Claim:
A moving picture encoding method, characterized in that the method comprises: an inter-frame prediction step of applying inter-frame prediction to an image on a block-by-block basis; a motion vector calculating step of calculating a reference frame and a motion vector for use in inter-frame prediction of said block; a predicted motion vector calculating step of calculating a predicted motion vector for prediction encoding of a motion vector of said block; a skip mode motion vector calculating step of calculating a skip mode motion vector for a skip mode using a context of blocks spatially adjacent to said block; and a skip mode validity deciding step of deciding whether the skip mode is valid as an encoding mode for said block, wherein said skip mode validity deciding step uses a code-amount based on said skip mode motion vector for the skip mode validity decision; wherein said skip mode validity deciding step uses for the skip mode validity decision a value obtained by weighting, with a quantization parameter of said block, a total value of a code-amount of a differential motion vector between said skip mode motion vector and said predicted motion vector corresponding to a reference frame for said skip mode and a value obtained by subtracting a predicted image of the skip mode motion vector from an original image of said block; and wherein said skip mode validity deciding step uses for the skip mode validity decision a value obtained by weighting, with a quantization parameter of said block, a code-amount of a differential motion vector between said skip mode motion vector and the motion vector calculated at said motion vector calculating step corresponding to a reference frame for said skip mode.