US Patent 7930176 Packet loss concealment for block-independent speech codecs

A technique for performing frame erasure concealment (FEC) in a speech decoder. One or more non-erased frames of a speech signal are decoded in a block-independent manner. When an erased frame is detected, a short-term predictive filter and a long-term predictive filter are derived based on previously-decoded portions of the speech signal. A periodic waveform component is generated using the short-term predictive filter and the long-term predictive filter. A random waveform component is generated using the short-term predictive filter. A replacement frame is generated for the erased frame. The replacement frame may be generated based on the periodic waveform component, the random waveform component, or a mixture of both.