G.729, G.729A and G.729AB Speech Vocoder
G.729, G.729A & G.729AB Vocoder
GAO’s G.729, G.729A & G.729AB vocoders provide toll-quality speech with only moderate processing requirements and delay times. They also perform well in the presence of random bit errors. The ITU-T G.729, G.729A & G.729AB standards are based on Code Excited Linear Prediction Model (CELP) and Conjugate-Structure Algebraic CELP (CS-ACELP). Some applications for GAO’s G.729, G.729A & G.729AB vocoders include visual telephony, wireless communications, and digital satellite communication systems.
The ITU-T G.729 standard offers superior bandwidth utilization making it an excellent alternative to applications that formerly used 32 Kbps ADPCM.
The G.729A ITU-T standard for voice coding compresses 8 kHz linear audio signals and encodes them for transmission at 8 Kbps with reduced complexity compared to G.729.
The ITU-T G.729B & G.729AB is a silence compression scheme for G.729 & G.729A optimized for terminals conforming to Recommendation V.70.
Features of G.729, G.729A & G.729AB Vocoder
- Compresses 8 kHz CODEC or linear audio data to 8 kbps.
- Operates on 10ms frames with short algorithm delays.
- Short-term synthesis filter is based on a 10th order Linear Prediction (LP) filter.
- Long-term, or pitch synthesis, filter is implemented using the adaptive-code book approach.
For other GAO speech compression demo, click Speech Compression Demo.
For a complete list of GAO’s Speech Vocoders Software products, please see GAO’s Speech Vocoders List.