SNR and bandwidth scalable speech coding
Hui Fen Dong, Jerry D. Gibson, M.G. Kokes · 2003
Bitrate scalability in speech coders can be used to achieve SNR scalable speech coding or bandwidth scalable coding of speech and audio. Depending upon the base layer bandwidth and base layer speech coder, several different scalable speech and audio coding structures have been investigated. We present a taxonomy of scalable speech coding structures and describe the advantages and disadvantages of each. We introduce an SNR scalable coder for noisy speech and propose the use of bandwidth scalable coders for rate switching in wireless environments. In addition, we develop a bandwidth scalable structure that is built around adaptive multirate speech coders.