Patent attributes
Entropy encoding is performed in the inventive apparatus and method in response to the scanning of transform coefficients following an initial scanning pattern selected on the basis of probability statistics of non-zero coefficients for each block position. These non-zero probability statistics are ranked for a given combination of coding characteristics within the current block to arrive at an initial scanning pattern. The same initial scanning pattern selection is performed in the decoder to allow the transform coefficients to be extracted in their proper order from encoded video data. The pattern selection is applicable to both intra prediction and inter prediction. Transform coefficients are more accurately ordered in response to the invention because in adapting pattern initialization to quantization step size, high-frequency basis functions are properly taken into account.
