An HSBE-LPC low bit wideband speech coding algorithm

This paper addressed the design, implementation and evaluation of a low bit-rate wideband speech coding algorithm HSBE-LPC based on Harmonic Sinusoidal Speech Model (HSSM) and Linear Predictive Coding technique. An improved HSSM was presented, where an improved sub-harmonic-harmonic high precision pitch algorithm to detect pitch, exacting frequency offsets and the SEEVOC to get envelope. The Voiced Possibility was iteratively computed combined with the Least Square Method of Sinusoidal Speech Model (SSM) technique on the basis of the obtained pitch and envelope. A split vector quantization method with Dynamic Time Warping to search codebook is used to encode LPC parameters obtained from amplitudes. The algorithm calculated LPC in frequency domain and picked up harmonic offsets to ensure high quality of re-construct speech. Simulation results and the mean opinion score (MOS) indicate that the proposed algorithm can reduce speech coding rate with high accuracy for speech parameter analysis, easy on-line realization and satisfied synthesis speech quality.