FIELD: information technologies.
SUBSTANCE: for DC- and DCAC-ratios from conversion, at internal stage of macroblock, codec calculates and compares directivity indices on the basis of DC-ratios of conversion at internal stage of neighbouring macroblocks, in order to identify dominant directivity. For DCAC-ratios from conversion, at external stage of blocks in macroblock, codec calculates and compares directivity indices on the basis of DCAC-ratios of conversion at internal stage of macroblock, in order to identify dominant directivity. Identification of directional dominance may also take into account information from other channels (for instance, chromaticity, and also brightness).
EFFECT: invention provides for method for forecasting conversion ratios, which takes into account dominant directivity of digital multimedia data, and additionally operates as compatible with double-stage conversion.
20 cl, 15 dwg
