A Packet Loss Recovery Method Using Packets Arrived behind the Playout Time for CELP Decoding(Speech and Hearing)

概要

論文の詳細を見る
This paper proposes a packet loss recovery method using packets arrived behind the playout time for CELP (Code Excited Liner Prediction) decoding. The proposed method recovers synchronization of the filter states between encoding and decoding in the period following packet loss. The recovery is performed by replacing the degraded filter states with the ones calculated from the late arrival packet in decoding. When the proposed method is applied to the AMR (Adaptive Multi-Rate) speech decoder, it improves the segmental SNR (Signal-to-Noise Ratio) by 0.2 to 1.8dB at packet loss rates of 2 to 10% in case that all the packet losses occur due to their late arrival. PESQ (Perceptual Evaluation of Speech Quality) results also show that the proposed method slightly improves the speech quality. The subjective test results show that five-grade mean opinion scores are improved by 0.35 and 0.28 at a packet loss rate of 5% at speech coding bitrates of 7.95 and 12.2 kbit/s, respectively.
社団法人電子情報通信学会の論文
2003-12-01