Patent ID: 7852947
Filing Date: 2010-12-14
Classification: H04N

Abstract:
1. A video decoding apparatus of 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 apparatus comprising: a receiver configured to receive an input of encoded data obtained by encoding, for a to-be-decoded block, (A) a quantized orthogonal transform coefficient of a prediction error signal concerning the luminance component and first and second color difference components and (B) an index indicating (1) a reference image and (2) a 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; a determining module configured to determine whether a decoding unit of the to-be-decoded block is a frame or a field; a deriving module configured to derive, for the to-be-decoded block, the weighting factors and the offsets from the index; a first generator configured to generate a prediction image by multiplying the luminance component and 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; a second generator configured to generate a prediction error signal by subjecting the quantized orthogonal transform coefficient to inverse quantization and inverse orthogonal transform; and a third generator configured to generate a decoded image signal by calculating a sum of the prediction error signal and the prediction image; wherein respective values of the indexes indicate the different combinations when the decoding unit is the frame; and two values of the index corresponding to different reference images indicate an identical combination when the decoding unit is the field.