Title :
Implementation of a low delay modified CELP coder at 4.8 kb/s
Author :
Zhang, Jian ; Wang, Hong-Shen ; Yu, Tian-Hu
Author_Institution :
Dept. of Inf. Eng., Chinese Univ. of Hong Kong, Shatin, Hong Kong
Abstract :
This paper presents a low delay high quality speech coder at low bit rates. The configuration of the speech coder is mainly composed of a formant filter, a pitch codebook, an excitation joint codebook, and post enhancement filters. The algorithm of the speech coder is briefly described. Two versions of the speech coder have been implemented in real-time with a single: ADSP-21020 chip. Both objective measurement and informal subjective listening tests show that the proposed speech coder has high quality performance
Keywords :
computational complexity; digital signal processing chips; filtering theory; linear predictive coding; speech coding; vocoders; 4.8 kbit/s; ADSP-21020 chip; CELP coder; excitation joint codebook; formant filter; informal subjective listening tests; low bit rates; low delay high quality speech coder; objective measurement; pitch codebook; post enhancement filters; Bit rate; Decoding; Delay; Filters; Linear predictive coding; Semiconductor device measurement; Speech analysis; Speech coding; Switches; Testing;
Conference_Titel :
Global Telecommunications Conference, 1995. GLOBECOM '95., IEEE
Print_ISBN :
0-7803-2509-5
DOI :
10.1109/GLOCOM.1995.500297
