Low rate audio coder with hierarchical filterbanks and lattice vector quantization

AND LATTICE VECTOR QUANTIZATION Peter Monta and Shiufun Cheung Advanced Television and Signal Processing Group Research Laboratory of Electronics Massachusetts Institute of Technology Cambridge, MA ABSTRACT We describe a perceptual audio coder that employs nonuniform hierarchical lterbanks and entropy-coded lattice vector quantization. The nonuniform lterbanks present a good match to critical-band sampling, and they avoid the complications of block-size adjustment during signal transients. An entropy-coded lattice vector quantizer provides e cient quantization and coding of the lterbank samples. The coder achieves \transparent" quality at a rate of 96 kb/s, and e cient algorithms exist for the lterbank and vector quantizer subsystems.