Patent ID: 7852929

Claim:
A prediction image generation method for generating a prediction image from encoded data obtained by subjecting a video image to prediction encoding, the video image having a luminance component and, first and second color difference components, the method comprising: receiving an input of encoded data obtained by encoding, for one or more to-be-decoded blocks, a plurality of combinations, each combination comprising (A) a first weighting factor for the luminance component, (B) a second weighting factor for the first color difference component, (C) a third weighting factor for the second color difference component, (D) a first offset for the luminance component, (E) a second offset for the first color difference component, and (F) a third offset for the second color difference component, and encoding, for a to-be-decoded block, a given number of indices each indicating (1) a combination selected from the plurality of combinations and (2) a reference image; deriving, for the to-be-decoded block, the given number of combinations of the weighting factors and the offsets from the given number of indices and the plurality of combinations; and generating a prediction image by multiplying the luminance component and the first and second color difference components of each of the given number of reference images respectively by the weighting factors corresponding to the respective reference images and adding the given number of offsets, respectively, to results of the multiplying.