Unicoi G.723.1 Codec
An audio codec for voice that compresses voice audio in chunks of 30 milliseconds. A look-ahead of 7.5 ms duration is also used. G.723.1 is mostly used in Voice over IP (VoIP) applications for its low bandwidth requirement.Unicoi G.723.1 codec consists of a separate encoder and decoder.
Each component is designed to support the different bit rates. The higher bit rate (6.3kbit/s) has greater quality. The lower bit rate (5.3kbit/s) still provides good quality but the performance is lower compared with the higher rate. Both rates are mandatory parts of the encoder and the decoder. The ITU-T recommendation specifies switching between the two rates on any frame boundary.
Unicoi G.711 µ/A – Law Codec
An implementation of the ITU-T G.711 recommendation. The encoder compresses linear PCM, sampled at 8 KHz using non linear quantization to 64Kbs. Two companding laws are supported,
A-law (commonly used in Europe and some Asian countries) and µ -law (commonly used in North America), are supported.
Unicoi G.722 Wide Band Support
ITU-T G.722 is the benchmark coder for wideband speech coding quality. Like all wideband speech coders, in G.722, the speech signal is sampled at 16KHz. Unicoi G.722 can handle speech and audio signal bandwidth up to 7 KHz, compared to 3.6 KHz in narrow band speech coders. Unicoi G.722 coder is based on the principle of Sub Band - Adaptive Differential Pulse Code Modulation (SB-ADPCM). The signal is split into two sub bands and samples from both bands are coded using ADPCM techniques. The system involving G.722 coder can be used to work in three modes 64, 56 and 48 kbit/s. 56 and 48 kbit/s modes will allow an auxiliary data channel of 8 and 16 kbit/s respectively, within the 64 kbit/s channel.
Unicoi DVI4 Codec
The DVI4 CODEC is a component of the Fusion Voice Engine. It has a very small memory footprint and uses very little processor bandwidth. This codec provides a 4 to 1 compression over linear data. This codec is slightly better than G.711 but only uses half of the bandwidth. This codec is also very forgiving in a high packet loss environment.
