Artificial bandwidth extension based packet loss concealment for CELP-type speech coders

Abstract

In this paper, a packet loss concealment (PLC) algorithm is proposed to improve the quality of decoded speech when packet losses occur in a codeexcited linear prediction (CELP)-type speech coder. The proposed PLC algorithm is based on artificial bandwidth extension (ABE) from narrowband to wideband, consisting of packet loss concealment in the narrow-band, ABE in the modified discrete cosine transform (MDCT) domain, and smoothing of wideband MDCT coefficients with those of the last good frame. The effectiveness of the proposed PLC algorithm is demonstrated by an informal listening test.