A good job well done: the latest wireless codecs deliver wireline quality

Abstract

The results of a listening test conducted at Nortel on behalf of the CDMA Development Group (CDG) suggest that the new crop of wireless codecs are all able to deliver voice quality comparable to wireline with single encoding over a clean wireless transmission channel. The codecs were tested with clean speech, varying input level, background noise, and tandem encoding. Given these findings, we hope to provoke discussion about the next challenges facing speech coding researchers and codec designers. The potential issues are: codec robustness to errors, noise reduction, and very-low bit rate codecs for a variety of applications.