Real-time implementation of low complexity transform coding.

A real time implementation of an adaptive transform coding algorithm (ATC) which fits on a single height Euro Card is discribed. Bit rate reduction from 16 bit (compact disc) down to 3 bit per sample at sampling rates up to 48 kHz can be demonstrated. This was achieved by modifying an ATC algorithm in order to minimize the number of calculations needed for coding and decoding. High quality is obtained by including psychoacoustic criteria in the coding algorithm. At 3.5 bit per sample quality degradation compared to the original from CD is not audible for most signals. The system is designed around a single chip signal processor which uses on chip 32 bit floating point hardware. One signal processor serves a stereo pair of sound channels. (AIS-A)