Speech Coding: Applications, Challenges and New Directions
P. Kroon · 1996
Inexpensive VLSI and an increasing demand for bandwidth effiaency have led to a large increase of the number of ap plications for speech coding. In the past 5 years, many standards have been defined for use in network and cellular communications systems. This widespread deployment of speech coding technology has created new challenges such as coding of speech with background noise, robust performance over noisy or fading channels, and performance for multiple encodings. In addition, many applications impose constraints on communication delay, cost and power consumption of the implementation. This paper will first review the underlying speech coding principles used in most international and regional standards. This is followed by a closer look at the trade-offs that can be made during the design of a speech coder. The last part of the paper will focus on the technical challenges and new directions of speech coding research for the next five years.