Patent ID: 7864851
Filing Date: 2011-01-04
Classification: H04N

Abstract:
1. A video decoding method for decoding encoded data obtained by subjecting a video image to motion compensation 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 one or more to-be-decoded blocks, a plurality of combinations each 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, (F) a third offset for the second color difference component, and (G) a flag indicating presence or non-presence of the weighting factor and the offset for the luminance component and encoding, for a to-be-decoded block, (1) a quantized orthogonal transform coefficient, (2) information of a motion vector and (3) an index indicating a combination selected from the plurality of combinations; deriving, for the to-be-decoded block, a combination comprising the weighting factors and the offsets from the index and the plurality of combinations; generating a prediction error signal for the to-be-decoded block by subjecting the quantization orthogonal transform coefficient to inverse quantization and inverse orthogonal transform; generating a motion compensation 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, respectively, by the weighting factors, and adding the offsets, respectively, to results of the multiplying, based on the motion vector for the to-be-decoded block; and generating a decoded image signal for the to-be-decoded block by calculating a sum of the prediction error signal and the motion compensation prediction image.