A Packet Loss Concealment Algorithm Robust to Burst Packet Losses for G.729

연속적인 프레임 손실에 강인한 G.729 프레임 손실 은닉 알고리즘

  • Cho, Choong-Sang (Department of Information and Communications Gwangju Institute of Science and Technology (GIST)) ;
  • Lee, Young-Han (Department of Information and Communications Gwangju Institute of Science and Technology (GIST)) ;
  • Kim, Hong-Kook (Department of Information and Communications Gwangju Institute of Science and Technology (GIST))
  • 조충상 (광주과학기술원 정보통신공학과) ;
  • 이영한 (광주과학기술원 정보통신공학과) ;
  • 김홍국 (광주과학기술원 정보통신공학과)
  • Published : 2007.05.18

Abstract

In this paper, a packet loss concealment (PLC) algorithm for CELP-type speech coders is proposed to improve the quality of decoded speech under a burst packet loss condition. The proposed algorithm is based on the recovery of voiced excitation using an estimate of the voicing probability and the generation of random excitation by permutating the previously decoded excitation. The voicing probability is estimated from the correlation using the previous correctly decoded excitation and pitch. The proposed algorithm is implemented as a PLC algorithm for G.729 and its performance is compared with PLC employed in G.729 by means of perceptual evaluation of speech quality (PESQ) and an A-B preference test under the random and burst packet losses with rates of 3% and 5%. It is shown that the proposed algorithm provides better speech quality than the PLC of G.729, especially under burst pack losses.

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