Title :
Wavelet linear prediction vocoder based on auditory model
Author :
Xun, Sun ; Du, Limin ; Howng, Wei-Yean
Author_Institution :
Lab. for Interactive Inf. Syst., Beijing, China
Abstract :
It is very difficult but very important to get higher quantity at lower bit rate in the field of speech coding. Traditional vocoders, such as LPC10e and CELPC, can give acceptable results but suffer from a hoarse output. We attribute this problem to the inconsistency between the equal resolution characteristic of linear prediction throughout the whole frequency band and the characteristic of the human ear´s unequal resolution at different frequency bands. In this paper, we present a new wavelet linear prediction subband coding algorithm (WLPSC), by employing a wavelet filter bank based on the auditory model. We divide the input speech signal into four subbands, and then code each subband respectively. Experimental results show that this algorithm can greatly reduce the hoarse output of vocoders
Keywords :
filtering theory; linear predictive coding; signal resolution; speech coding; transform coding; vocoders; wavelet transforms; auditory model; equal resolution characteristic; hoarse output; speech coding; subband coding algorithm; unequal resolution; wavelet filter bank; wavelet linear prediction vocoder; Bandwidth; Biomembranes; Bit rate; Ear; Filter bank; Frequency; Humans; Predictive models; Speech coding; Vocoders;
Conference_Titel :
Signal Processing Proceedings, 1998. ICSP '98. 1998 Fourth International Conference on
Conference_Location :
Beijing
Print_ISBN :
0-7803-4325-5
DOI :
10.1109/ICOSP.1998.770282