Fixed-Location Pulse Linear Prediction Coding Vocoder Model for Low Bit Rate Speech Coding

Low-bit-rate Speech Coding

Low-bit-rate speech coding, at rates below 4 kb/s, is needed for both communication and voice storage applications. At such low rates, full encoding of the speech waveform is not possible; therefore, low-rate coders rely instead on parametric models to represent only the most perceptually-relevant aspects of speech. While there are a number of different approaches for this modeling, all can be ...

Title A phonetic Vocoder for Very-Low-Rate Speech Coding

Low Bit Rate Speech Coding via TCVRQ

We present a new Trellis Coded Vector Residual Quantizer (TCVRQ) that combines trellis coding and vector residual quantization. We introduce new methods for computing quantization levels and experimentally analyze the performances of our TCVRQ in the case of speech coding at very low bit rates. The results obtained show that transparent quantization of Linear Prediction (LP) parameters can be p...

Low bit rate wideband WI speech coding

This paper investigates Waveform Interpolation (WI) applied low bit rate wideband speech coding. An analysis of the evolutionary behaviour of wideband Characteristic Waveforms (CWs) shows that direct application of the classical WI algorithm may not be appropriate for wideband speech. We propose a modification whereby CW quantisation is performed using classical WI decomposition for the low fre...

Low bit rate coding for speech and audio using mel linear predictive coding (MLPC) analysis

This paper proposes a low bit rate coding method for speech and audio using a new analysis method named MLPC (Mel-LPC analysis). In the MLPC analysis method a spectrum envelope is estimated on a melor bark-frequency scale, so as to improve the spectral resolution in the low frequency band. This analysis is accomplished with about two-fold increase in computation over the standard LPC analysis. ...