A new wavelet transform-based CELP coder with band selection and selective VQ

In this paper, we present a new coding algorithm of discrete wavelet transform (DWT) coefficients in a wavelet transform-based CELP coder, and introduce a new WT-based CELP coder, named the band selection wavelet transform-based CELP (BS-WTCELP). The proposed algorithm adopts a band selection and selective vector quantization (VQ) of DWT coefficients. We realize this band selection and selective VQ scheme by using a classified VQ structure. Experimental results have shown that the proposed coder achieves about 0.41-1.14 dB improvement in segmental SNR while considerably reducing the computational complexity compared with the conventional coders.