Importance

Loading Importance Indicators...

Abstract

The invention relates to the encoding of pixel blocks. To apply some encoding tools, an input 4:2:0 block is upsampled into a 4:4:4 block. Each color component of the 4:4:4 block has thus the same importance when evaluating a distortion measure. To vary the influence of the colour components depending on their impact on the decoding, the invention provides assigning weights to the colour components of pixels of the 4:4:4 block depending on whether the corresponding colour components exist in the 4:2:0 block, due to the subsampling. In such a case, any measure is evaluated using the weighted colour components. This approach may apply to the palette coding mode, for instance when updating the colour component values of a palette entry upon building, or selecting the closest palette entry to a pixel currently considered, or also determining whether a palette entry predictor may be used instead of a palette entry.

Loading the Abstract Image...

First Claim