Video encoding/ decoding method and apparatus

Abstract

A video encoding method comprises selecting one combination, for each block of an input video signal, from a plurality of combinations each including a predictive parameter and at least one reference picture number determined in advance for the reference picture, generating a prediction picture signal in accordance with the reference picture number and predictive parameter of the selected combination, generating a predictive error signal representing an error between the input video signal and the prediction picture signal, and encoding the predictive error signal, information of the motion vector, and index information indicating the selected combination.

1 . A prediction image generation method for generating a prediction image from encoded data obtained by subjecting a video image having luminance and two color differences to prediction encoding, comprising:
 receiving encoded data obtained by encoding, for a to-be-decoded block, an index indicating (A) a combination of (1) a weighting factor every luminance and two color differences and (2) an offset every luminance and two color differences and (B) a reference image;   deriving the weighting factor and the offset from the index for the to-be-decoded block; and   generating a prediction image by multiplying the reference image by the weighting factor and adding the offset, and   wherein the weighting factor and the offset derived from the two an index elements corresponding to the reference images different respectively are identical.