An 800bps VQ Based LPC Voice Coder
نویسندگان
چکیده
The idea of applying vector quantization (VQ) to linear prediction coding (LPC) to realize a very low bit-rate speech coder with reasonable speech quality is investigated in this research. Instead of encoding LPC parameters directly, line spectral frequency (LSF) coefficients are obtained through a transformation of LPC and then encoded via VQ in the proposed scheme. In order to utilize the inter-frame correlation, three frames of speech data are processed together. MSE is selected as the distortion measure in building the split VQ codebooks. With this new coder, the coding bit-rate can be reduced to 800 bps with qua[ity similar to that obtained by the LPC 2.4kbps speech coder.
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