Title :
Recent progress in low-bit-rate speech coding
Author_Institution :
Inst. fuer Angewandte Phys., Johann Wolfgang Goethe-Univ., Frankfurt am Main, Germany
Abstract :
RELP schemes, which are based on a model of the vocal tract and the estimation of an optimum excitation function, are reviewed. In the RELP-S scheme the speech signal is interpreted as the result of filtering synthetic excitation functions by a filter which models the vocal tract. Two types of RELP-S schemes using different excitation generators are described. Refinements of this concept as vector sum excited linear prediction (VSELP) and post-filtering strategies lead to CELP codecs at rates between 8 kb/s and 4.8 kb/s able to achieve a speech quality which is scored between fair and good in subjective MOS-terms
Keywords :
codecs; encoding; speech analysis and processing; 4.8 kbit/s; 8 kbit/s; CELP codecs; RELP-S scheme; low-bit-rate speech coding; optimum excitation function; post-filtering; speech quality; speech signal; synthetic excitation functions; vector sum excited linear prediction; Bit rate; Decoding; Encoding; Filters; Phase change materials; Signal processing; Speech coding; Speech processing; Speech synthesis; Technological innovation;
Conference_Titel :
Electrotechnical Conference, 1991. Proceedings., 6th Mediterranean
Conference_Location :
LJubljana
Print_ISBN :
0-87942-655-1
DOI :
10.1109/MELCON.1991.161775
