A hybrid coder using the wavelet transform

A hybrid music coder using the wavelet transform (WT) is proposed. By use of the WT, the signal is decomposed into subbands with octave bandwidth. The authors propose to use the modulated lapped transform (MLT) and vector quantization (VQ) to code the detail signals so as to cope with their composite sinusoids nature. As the approximated signal is at a much lower rate than the original signal, it can be coded by linear predictive coding (LPC) or an analysis-by-synthesis technique. To further reduce the complexity of the coder, a fast vector quantization (VQ) search algorithm using the orthogonal hyperplane search is developed