Packet Loss Concealment for G.722 using Side Information with Application to Voice over Wireless LANs

The G.722 wideband speech codec offers higher quality and better naturalness than G.711, is low in complexity, has low delay, and tandems well with other codecs. This makes it an attractive codec for Voice over IP and Voice over Wireless LANs. However, loss of a G.722 coded speech frame results in a mismatch of the encoder/decoder states that affects the decoding of subsequent correctly received frames. We present a new packet loss concealment (PLC) method for G.722 and propose an efficient approach to sending the side information to improve concealment of the lost frame and to resynchronize the encoder and decoder. The proposed method greatly improves the robustness of the G.722 codec to packet losses for Voice over Wireless LANs. Wideband Perceptual Evaluation of Speech Quality Mean Opinion Score (WB-PESQ MOS) is used as the quality metric for evaluating the performance of the PLC schemes.