An Investigation of Sinusoidal Speech Coding
Zhenjie Wu, W.H. Holmes · Information Sciences, Signal Processing and their Applications · 1996
This paper reports on a study of low bit rate speech coding based on the sinusoidal model proposed by McAulay and Quatieri. Several techniques are employed to reduce the coder's bit rate and increase the processing speed. Firstly, the Hilbert transform is used to estimate the system phase response. Secondly, a bilinear transform is used to warp the spectrum to exploit the auditory characteristics of the human ear when coding at very low rates. Thirdly, a method to estimate the initial pitch for the SEEVOC model is introduced. Finally, a simplified birth-and-death algorithm is presented. The simulation results show that the synthetic speech is of good quality at a bit rate of 4800 b/s, and is still intelligible and speaker recognizable at 1200 b/s.