Method and system for concealing frame error in speech decoder by replacing spectral parameter

The present invention discloses a spectral parameter substitution method and system for speech decoder frame error concealment method of the invention comprises the steps of: determining whether the received speech frame is a bad frame; counts the number of consecutive bad frames; good neighbor of the current bad frame according to the pitch period trends of spectral parameters of the current frame bad frame for recovery. According to the present invention, the pitch period of the neighbor of the current bad frame good frame trend, a smooth continuous adaptive average neighbor good frame to replace the bad frame spectral parameter to hide a bad frame is received by the speech decoder via the communication channel influences. The present invention can find the most suitable replacement for the bad frame spectral parameter, can improve the subjective quality of synthesized speech.