G.729

This ITU-T standard is very useful for audio data compression applications.  It is works at 8 kbit/sec while following the CS-ACELP (Conjugate-structure algebraic-code excited linear-prediction)

This compresses the voice audio in 10 millisecond frame while being the perfect algorithm for voice compression.

This is normally applied at VoIP (Voice over internet protocol applications due to its less bandwidth requirements.

Following are the extended versions of G.729.

G.729a/G.729 Annex A
It is conforming to G.729 Annex A that specifies the coder with multiple simplicities such as code book search routines.  Such changes are commonly known to major result in a less voice degrees.

G.729b/G.729 Annex B
It is also compatible with G.729, Annex B. It denotes a coder which follows DTX (Discontinuous Transmission) VAD (Voice Activity Detection) and CNG (Comfort Noise Generation in order to lessen the usage of bandwidth.