A new low bit rate speech coder based on intraframe waveform interpolation
نویسندگان
چکیده
A new characteristic waveform (CW) interpolation coder is proposed in this paper. In the proposed coder, two characteristic waveforms are extracted from LPC residual signal at each frame. The Waveform Interpolation (WI) is operated within the frame. In the novel WI, variable dimension vector quantization (VDVQ) and power vector quantization are proposed and the low frequency band (LFB) and high frequency band (HFB) are allocated different numbers of bits according to human hearing perception. A result of a 2400 bps coder is presented and the reconstructed speech shows its quality is closed to FED-STD-1016.
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