A Characteristic Waveform Decomposition Algorithm Using Biorthogonal Wavelet Transform

This paper presents a characteristic waveform decomposition algorithm based on wavelet transform. The characteristic waveform surface is decomposed into a series of reduced time resolution surfaces. The biorthogonal linear phase filter banks based on B-spline wavelet are performed in the evolutionary waveform domain. This multi-scale characteristic leads to more efficient quantization by exploiting each surface´s perceptual importance and inherent transmission rate requirements. The waveform interpolation coder based on wavelet decomposition and reconstruction performs well with efficient quantization and is very suitable for speech storage. Also a 3.3 kbps waveform interpolation speech coder is proposed based on the wavelet-based waveform decomposition algorithm. For low delay application, casual, stable IIR filters or low-delay FIR filter designing method can be used