A double-side WSOLA with gain prediction based on GRU for packet loss concealment

摘要

The perceived speech quality is one of the main issues in VoIP communications. Packet loss concealment (PLC) is among the best techniques to recover the lost packets over IP networks in order to improve the speech quality. In this paper, a double-side waveform similarity overlap and add(WSOLA) technique has been proposed in which both previously received packets and future packets involve in recovering the lost packets by using WSOLA technique. To overcome energy decrease that occurs during the waveform reconstruction, a gated recurrent unit (GRU) based gain control approach has been introduced to maintain the energy of a reconstructing waveform with the prediction of the lost packets gain by learning the previously received packets gain. The proposed algorithm has shown the outperformance to the standard WSOLA and double-side WSOLA without gain control at both random and burst packet loss according to the obtained perceptual evaluation of speech quality (PESQ) results.