Improved Frame Error Concealment Algorithm Based on Transform-Domain Mobile Audio Codec

摘要

In this paper, we propose an improved frame error concealment algorithm for TCX-based audio coders in orderto improve the quality of decoded audio at the receiver. Conventional TCX-based frame error concealment algorithmsin the AMR-WB+ audio codec are usually unable to adaptively adjust gain control according to changes in the magnitudeof the correct frame before lost frames. Thus, we propose a new gain control approach based on stability of LPC filter,and the stream data need to contain the line spectrum frequency data and utilize different continuous attenuation factorformula based on different categories of lost frames. The proposed frame error concealment algorithm is designed forTCX-based audio codec. We make the performance comparison between the proposed method and the original algorithmcurrently employed in AMR-WB+ audio codec through the objective evaluation test and subjective evaluation test. Theresults prove that our algorithm can achieve better audio recovery quality than original frame error concealment algorithmemployed in AMR-WB+ speech codec.