A novel BWE scheme based on spectral peaks in G.729 compressed domain

This paper addresses the problem of interoperability of narrowband VoIP network with wideband wireless network. Bandwidth extension in G.729 compressed domain is proposed to address this problem. The proposed method is based on spectral envelope extension using classified codebook approach. The number of spectral peaks is used as the feature for classification in this method. The proposed method gives a performance improvement of around 0.8dB with respect to existing method of Decode Then Extend (DTE). This compressed domain method also reduces the computational cost by around 2.5 MIPS on TMS320C55x DSP with respect to DTE.