Multiprocessor implementation of an ATC audio codec

A source coding scheme for high-quality audio signals based on adaptive transform coding is presented. Using the well known ATC algorithm of R. Zelinski and P. Noll (1977) as a starting point, the authors have developed an algorithm that features psychoacoustic weighting and a joint bit allocation to stereo channels. The real-time implementation uses a four-node processor network, each node consisting of a T800 transputer and a DSP32 signal processor. Both the codec optimization and the evaluation of subjective quality are facilitated by the fact that many of the codec parameters can be changed online. >