Title :
A high quality MBE-LPC-FE speech coder at 2.4 kbps and 1.2 kbps
Author :
Wang, Tian ; Tang, Kun ; Feng, Chongxi
Author_Institution :
Dept. of Electron. Eng., Tsinghua Univ., Beijing, China
Abstract :
This paper presents a high quality speech coder based on the multi-band excitation (MBE) model operating at 2.4 kb/s and 1.2 kb/s. The features of this coder mainly focus on two aspects. One is an accurate and reliable pitch estimation and voiced/unvoiced decision algorithm. The other is the efficient quantization of the variable dimension spectral amplitude vector. Besides representing the spectral envelope information using an all-pole model, we also encode error vectors of the spectral amplitude vector at several important positions. Informal listening tests indicate that the speech quality of this coder at 2.4 kb/s is comparable and even superior to the INMARSAT-M IMBE 4.15 kb/s coder. The coder has been implemented in real-time on a single TMS320C31 floating point DSP
Keywords :
digital signal processing chips; floating point arithmetic; linear predictive coding; spectral analysis; speech coding; vocoders; 1.2 kbit/s; 2.4 kbit/s; MBE-LPC-FE; TMS320C31 floating point DSP; all-pole model; formant enhancement; high quality speech coder; informal listening tests; linear predictive coding; low bit rate; multi-band excitation; pitch estimation; quantization; real-time implementation; spectral amplitude vector; spectral envelope information; speech quality; voiced/unvoiced decision algorithm; Bit rate; Discrete cosine transforms; Frequency estimation; Linear predictive coding; Quantization; Reliability engineering; Speech coding; Speech synthesis; Testing; Vectors;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1996. ICASSP-96. Conference Proceedings., 1996 IEEE International Conference on
Conference_Location :
Atlanta, GA
Print_ISBN :
0-7803-3192-3
DOI :
10.1109/ICASSP.1996.540327
