A Simplified Algorithm for Representation and Alignment of the Characteristic Waveform in WI Speech Coding

Waveform interpolation (WI) speech coding has a good performance compared with various low bit rate coders, and provides high-quality reconstructed speech. However, characteristic waveform (CW) representation and alignment in WI model has very high complexity in computation. This has restricted its further developments and practical applications. The improved algorithm for CW representation and CW alignment was proposed by using FFT, cubic B-spline interpolation and period extension in this paper. The experimental results show that the improved algorithm has greatly reduced the computational complexity and kept the same speech quality as original coder