harmonic vector excitation (speech encoding) (HVXC)

Harmonic Vector Excitation (HVXC) is a speech-optimized parametric speech compression method that operates at 8 kHz and produces data rates from 2 kbit/s to 6 kbit/s.

In this highly efficient speech compression, the residual signal from Linear Predictive Coding( LPC) is transformed and then parametrized. InMPEG-4 V.2, the capabilities of HVXC are extended by variable bit rate( VBR). The HVXC process is used in digital broadcasting, among other applications.