ITU-T G.729 with Annex B Speech Coder for the TMS320C55x Generation

Description

The ITU-T G.729 with Annex B 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.

Annex B implements optional silence-compression techniques to reduce the transmitted bit rate during the silent periods of speech. Discontinuous transmission systems (DTX) use Voice Activity Detection (VAD) and Comfort Noise Generation (CNG). The coder uses occasional Silence Insertion Descriptor (SID) frames during silence.

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

The G.729 with Annex B is part of the DSP Wizard G.729 suite for TMS320C55x, which is comprised of five separate products:

Features

DSP Wizard’s G.729 with Annex B implementation was designed for low resource requirements without sacrificing quality. It executes at 13.5 mips for worst-case data. The speed is at least 25% faster than any other G.729 Annex B c55x implementation available. While it may seem that many DSP software vendors claim to have the best speeds, we can back up our claim. Please compare us to the competition. A 200 MHz c55x chip can support 14 channels.

• Highly optimized for TMS320C55x
• Bit-exact fixed-point implementation per ITU-T test suite
• Fully reentrant—self-preemptible
• Multichannel
• Simple integration into existing systems via C-callable functions
• TI eXpressDSP compliant algorithm
• Release/version 1.0
• Available now
• Delivered as a Zip file

Performance

dspwizard@dspwizard.com