Title :
Adaptivity Versus Tree Searching in DPCM
Author :
Chan, H.C. ; Anderson, J.B.
Author_Institution :
Government of Canada, Ottawa, Canada
fDate :
5/1/1982 12:00:00 AM
Abstract :
The interaction is studied between the effects of tree searching and predictor and quantizer adaptation in a differential pulse-code modulation (DPCM) speech digitizer. The maximum entropy method computes a new source model every 8 ms, and a variety of strategies are used to adapt the quantizer. Results are displayed in plots of local SNR versus time. It is found that the predictor, the quantizer, and the tree search each contribute roughly independently to the total SNR. Adaptivity contributes in total 6-7 dB and tree searching 2-3 dB.
Keywords :
pulse code modulation; speech analysis and processing; trees (mathematics); SNR; differential pulse-code modulation; maximum entropy method; predictor; quantizer adaptation; speech digitizer; tree searching; Books; Decision trees; Delay; Digital modulation; Entropy; Gain; Least squares approximation; Mean square error methods; Pulse modulation; Speech coding;
Journal_Title :
Communications, IEEE Transactions on
DOI :
10.1109/TCOM.1982.1095571
