Title :
An embedded scheme for regular pulse excited (RPE) linear predictive coding
Author :
Zhang, Shude ; Lockhart, Gordon
Author_Institution :
Dept. of Electron. & Electr. Eng., Leeds Univ., UK
Abstract :
The feasibility and performance of an embedded RPE (ERPE) scheme based on multistage coding is investigated. The coding efficiency of second and subsequent stages depends on the spectral envelope difference between the original speech and the error signal at each stage whereas re-use of LPC parameters derived from the original speech depends on the corresponding LPC spectral difference. Suitable measures of spectral difference are defined and simulation shows that both decrease with the perceptual weighting factor. The ERPE system requires little extra coding complexity and can be simplified further by using a partial phase adaptation procedure with marginal loss of SNR performance. The simulated ERPE system shows graceful reduction of reconstructed speech quality for bit rates from 14.8 to 6.4 kb/s in 4.2 kb/s steps
Keywords :
adaptive signal processing; linear predictive coding; real-time systems; signal reconstruction; spectral analysis; speech coding; speech intelligibility; LPC parameters; LPC spectral difference; SNR performance; bit rates; coding complexity; coding efficiency; embedded scheme; error signal; linear predictive coding; multistage coding; original speech signal; partial phase adaptation; perceptual weighting factor; performance; reconstructed speech quality; regular pulse excited coding; simulation; spectral envelope difference; Bit rate; Communication system control; Decoding; Degradation; Delta modulation; Filters; Linear predictive coding; Performance loss; Predictive coding; Speech coding;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 1995. ICASSP-95., 1995 International Conference on
Conference_Location :
Detroit, MI
Print_ISBN :
0-7803-2431-5
DOI :
10.1109/ICASSP.1995.479267
