Implementation and optimization of a real-time PAC codec

We describe an implementation of the PAC audio compression algorithm [1,2] on PowerPC hardware designed to support simultaneous real-time compression and decompression of audio for transmission over a network. We describe the algorithm variant used, the target hardware and software development tools, and then describe the various optimizations that reduced the complexity sufficiently to allow the algorithm to run in real-time. We conclude by describing a scheduling algorithm that allows us to manage the complexity associated with the compression of 'difficult' music.