Improved recovery techniques for parametric lost frame predictive coding systems voice.

摘要

A method for recovering a lost frame for a system of the type in which information is transmitted in successive frames of encoded signals and wherein the information is reconstructed from said encoded signals at a receiver, said method comprising: storing encoded signals from a first frame prior to said lost frame; storing encoded signals from a second frame subsequent to said lost frame; interpolating between the encoded signals from said first and second frame to obtain encoded signals corresponding to said lost frame; calculating a fundamental period of the voice (pitch lag) and estimated prediction gain for the first frame; characterized by the step of classifying said lost frame as speech or unvoiced frame based on said prediction gain and estimated fundamental period the first frame.