Higher Compression Rates for ITU-T G.729

Abstract

In this paper, we exploit the loss less Hamming Correction Code Compressor (HCDC) in compressing the parameters of the ITU-T G.729 Conjugate Structure Algebraic Code Exited Linear Prediction Annex D of 6.4 Kbps. The CODEC Parameters were generated using the standard ITU source Codes. These parameters includes Linear Prediction Coefficients represented as LSPs, Gain and Excitation Bits, forming 64 bits represents 10 ms frames. These frames are grouped into four frames of 256 bits and subjected to the HCDC algorithm. Testing data set used were for adult English speaking males and females. HCDC were able to reduce transmission rate by 50% in average using the. The results were compared to the entropy compression methods (Golomb-Rice) which is implemented in FLAC package, these methods could reduce the data rate by 22% in average. The overall compression performance were calculated with averaging the compression rates for all frames for each sample. HCDC were able to compress on parity=3 only, for other parity values, few blocks were valid, but the overall compression rate for the frames were below 1.