Patent ID: 7848422
Filing Date: 2010-12-07
Classification: H04N

Abstract:
1. A video decoding apparatus of decoding encoded data obtained by subjecting a video image to predictive encoding, the video image having a luminance component and, first and second color difference components, the apparatus comprising: a receiver configured to receive 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 and non-presence of the weighting factors and offsets for the first and second color difference components and encoding, for a to-be-decoded block, (1) a quantized orthogonal transform coefficient of a prediction error signal concerning the luminance component and the first and second color difference components and (2) an index indicating a combination selected from the plurality of combinations; a deriving module configured to derive, for the to-be-decoded block, a combination comprising the weighting factors and the offsets from the index and the plurality of combinations; a first generator configured to generate the prediction error signal for the to-be-decoded block by subjecting the quantized orthogonal transform coefficient to inverse quantization and inverse orthogonal transform; a second generator configured to generate a prediction image for the to-be-decoded block by multiplying the luminance component and the first and second color difference components of a reference image, respectively, by the weighting factors, and adding the offsets, respectively, to results of the multiplying; and a third generator configured to generate a decoded image signal for the to-be-decoded block by calculating a sum of the prediction error signal and the prediction image.