Title :
Multimode coding: application to CELP
Author :
Taniguchi, Tomohiko ; Unagami, Shigeyuki ; Gray, Robert M.
Author_Institution :
Fujitsu Lab. Ltd., Kawasaki, Japan
Abstract :
The authors introduce a novel approach to narrow- and medium-band speech coding that can dynamically balance the transmission rate between the excitation and the spectral parameters. The coding algorithm, called multimode coding, operates several coding blocks, each of which has a different bit assignment in parallel, and selects the optimum coding block frame by frame based on an evaluation of the reproduced speech quality. This coding algorithm is applied to 4.8 and 8.0 kb/s CELP coders, and 2.0-2.4 dB of SNRseg improvement is achieved over conventional CELP coders. The spectral distortion measure is added as an evaluation function, improving the subjective speech quality
Keywords :
encoding; filtering and prediction theory; speech analysis and processing; 4.8 kbit/s; 8 kbit/s; CELP; code excited linear prediction; medium-band coding; multimode coding; narrow-band coding; spectral distortion measure; speech coding; speech quality; Bit rate; Codecs; Distortion measurement; Laboratories; Linear predictive coding; Signal processing; Signal processing algorithms; Speech analysis; Speech coding; Speech processing;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1989. ICASSP-89., 1989 International Conference on
Conference_Location :
Glasgow
DOI :
10.1109/ICASSP.1989.266387
