Convention Paper
Time Domain Extrapolative Packet Loss Concealment for MDCT Based Voice Codec
AES Convention 138 · Paper 9263 · May 2015
Abstract
A novel low latency packet loss concealment technique for transform-based codecs is proposed. The algorithm combines signals from Inverse Modulated Discrete Cosine Transform (IMDCT) domain and the previous reconstructed signal from time domain with aligned phase, with which a pitch-synchronized concealment is performed. This minimizes aliasing artifacts that occur in MDCT domain concealment for voiced speech signals. For unvoiced speech, speech-shaped comfort noise is inserted. When there is a burst loss, a position-dependent concealment process is performed for different stages of packet losses. Subjective listening tests using both naïve and expert listeners suggest that the proposed algorithm generates fewer artifacts and offers significantly better performance against legacy packet repetition based approaches.
