A Speech Packet Loss Concealment Method Using Linear Prediction(Speech and Hearing)
スポンサーリンク
概要
- 論文の詳細を見る
We proposed and evaluated a speech packet loss concealment method which predicts lost segments from speech included in packets either before, or both before and after the lost packet. The lost segments are predicted recursively by using linear prediction both in the forward direction from the packet preceding the loss, and in the backward direction from the packet succeeding the lost segment. Predicted samples in each direction are smoothed by averaging using linear weights to obtain the final interpolated signal. The adjacent segments are also smoothed extensively to significantly reduce the speech quality discontinuity between the interpolated signal and the received speech signal. Subjective quality comparisons between the proposed method and the the packet loss concealment algorithm described in the ITU standard G.711 Appendix I showed similar scores up to about 10% packet loss. However, the proposed method showed higher scores above this loss rate, with Mean Opinion Score rating exceeding 2.4, even at an extremely high packet loss rate of 30%. Packet loss concealment of speech degraded with G.729 coding, and babble noise mixed speech showed similar trends, with the proposed method showing higher qualities at high loss rates. We plan to further improve the performance by using adaptive LPC prediction order depending on the estimated pitch, and adaptive LPC bandwidth expansion depending on the consecutive number of repetitive prediction, among many other improvements. We also plan to investigate complexity reduction using gradient LPC coefficient updates, and processing delay reduction using adaptive forward/bidirectional prediction modes depending on the measured packet loss ratio.
- 社団法人電子情報通信学会の論文
- 2006-02-01
著者
-
Kondo Kazuhiro
Graduate School Of Sci. And Engineering Yamagata Univ.
-
KONDO Kazuhiro
the Faculty of Engineering, Yamagata University
-
NAKAGAWA Kiyoshi
the Faculty of Engineering, Yamagata University
-
Nakagawa Kiyoshi
The Faculty Of Engineering Yamagata University