High-fidelity audio compression: fractional-band wavelets

Real-time algorithms for the compression of high-fidelity audio are under study. The goal of these algorithms is to provide a compact digital representation for an input stream of audio sample. A subband coding system that performs this is presented. This modular system combines a wavelet-based signal transformation block with adaptive quantization and lossless compression blocks. The design of the signal transformation block is examined. Designs are presented for filter structures that generate fractional octave and geometric subband partitionings of the input frequency band. In particular, designs for 1/2-octave, 1/3-octave and some geometric band partitionings are presented