SCALABLE COMPRESSED AUDIO BIT STREAM AND CODEC USING HIERARCHICAL SET OF FILTERS AND MULTICHANNEL COMPOSITE CODING Russian patent published in 2010 - IPC H03M7/30 

FIELD: information technology.

SUBSTANCE: method of compressing input audio signals to form a main bit stream which can be scaled in order to form a scaled bit stream having arbitrary prescribed data transmission speed. A hierarchical set of filters decomposes the input signal into a time/frequency presentation with multiple clearance levels, from which a coder can efficiently extract tonal (2106) and residual components. Components are ranked and then quantised based on a certain masking function or different psycho-acoustic criteria. Selected tonal components are properly coded using differential encoding distributed on a mutichannel audio signal. Components of time sampling and scaling factor, which form residual components, are coded using composite channel coding (CCC) which is distributed on the multichannel audio signal. The decoder uses a reverse hierarchical set of filters to reconstruct audio signals from the tonal and residual components in the scaled bit stream.

EFFECT: high coding efficiency and wider range of scaled data transmission speeds.

45 cl, 22 dwg