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ITU-T G.729 Annex A Speech Coder for the TMS320C64x+ Generation

[eXpressDSP Compliant]

Description

The ITU-T G.729 Annex A fixed-rate speech coder provides toll quality at very low bandwidth. G.729 compresses narrowband linear speech signals at a sample rate of 8kHz to 8kbps, using Conjugate-Structure, Algebraic Code-Excited Linear Prediction (CS-ACELP). The encoder extracts the parameters of the CELP coding model from 10-msec frames. G.729 Annex A is a less mathematically complex version of G.729. It requires roughly one half the cycles of G.729, yet is interoperable with it, with barely any loss of fidelity.

G.729 Annex A encoder is widely used in applications that require robust quality, including videoconferencing, internet, multimedia communications, satellite communications, and store/forward.

The G.729 Annex A is part of the DSP Wizard G.729 suite for TMS320C64x+, which is comprised of two products:

Algorithm Complexity SID Frames Bit-rate
G.729 Annex A Low No 8.0kbps
G.729 Annex A Annex B Low Yes 8.0kbps

Features

DSP Wizard’s G.729 Annex A implementation was designed for low resource requirements without sacrificing quality. It executes at 5.4 mips for worst-case data.

Performance

G.729 Annex A Encoder Decoder Full Duplex
Program Code Memory (Kbytes) 25.9 11.4 33.2
Program Table Memory (Kbytes) 0.0 0.0 0.0
Data Table Memory (Kbytes) 5.3 4.2 5.3
Per Channel Data Memory (Kbytes) 1.2 0.8 2.0
Stack Memory (Kbytes) 2.9 1.5 2.9
Interrupt Latency (cycles) 1000 1000 1000
Call Period (ms) 10 10 10
Processor Load: Worst-Case (MHz) 4.5 0.9 5.4

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