Patent ID: 7869513

Claim:
A prediction image generation method for decoding 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 encoded data obtained by encoding, for a to-be-decoded block, an index indicating (a) a reference image, (b) a first weighting factor for the luminance component, (c) a second weighting factor for the first color difference component, (d) a third weighting factor for the second color difference component, (e) a first offset for the luminance component, (f) a second offset for the first color difference component, and (g) a third offset for the second color difference component; deriving, for the to-be-decoded block, (b) a first weighting factor for the luminance component, (c) a second weighting factor for the first color difference component, (d) a third weighting factor for the second color difference component, (e) a first offset for the luminance component, (f) a second offset for the first color difference component, and (g) a third offset for the second color difference component from the index; and generating a prediction image for the to-be-decoded block by multiplying the luminance component and the first and second color difference components of the reference image by the weighting factors, respectively, and adding the offsets, respectively, to results of the multiplying.