Multilevel optimization of speech coding algorithms for modern DSP architectures

Real-time implementation of speech coding algorithm requires the DSP code to be highly optimized and the underlying hardware to be fast. This paper presents the results obtained from multi-level optimization of ITU-T G.729A low complexity speech codec on an embedded DSP platform. The implementation platform used in this work is based on analog devices Blackfin BF533 fixed-point media processor. Several high-level and low-level optimization techniques have been concurrently employed in this work to improve the run-time performance of the codec. Improvement in performance has been evaluated through the reduction in MIPS count for each optimization step. Results show that over twenty full-duplex channels of G.729A can be supported on this DSP platform in real-time.