A combined WI and MELP coder at 5.2 kbps
Jan Skoglund, Richard Vandervoort Cox, J.S. Collura · 2002
This paper presents a low bit rate speech coder that encodes speech using two parallel coders into one embedded bit frame structure of 5.2 kbps. The two coders, a mixed excitation linear predictive coder (MELP) and a waveform interpolation (WI) coder, share the same pitch and linear prediction analysis and quantization. The combined coder is structured to provide a higher performance option of WI while maintaining compatibility with standard 2.4 kbps MELP via an embedded MELP mode.