11 Error concealment of lost frames

26.4413GPPCodec for Enhanced Voice Services (EVS)General overviewRelease 17TS

The EVS coder error concealment of erroneous or lost frames is described in [2] & [7].

Frames may be erroneous due to transmission errors or frames may be lost or delayed due to packet loss in a transport network. The methods described in [2] & [7] may be used as a basis for error concealment.

In order to mask the effect of isolated erroneous/lost frames, the decoder shall be informed about erroneous/lost frames and the error concealment actions shall be initiated, whereby a set of predicted parameters are used in the speech synthesis. Insertion of speech signal independent silence frames is not allowed.