An effective hybrid low delay packet loss concealment algorithm for MDCT-based audio codec

摘要

This paper proposes a hybrid packet loss concealment (PLC) algorithm for the MDCT-based audio codec with different PLC strategies on tone dominant source signals and noise like signals respectively. It is meaningful to find that the phase angle of the MDCT-MDST coefficients decreases linearly with the increase of the frame index but the amplitude keeps unchanged for the stationary source signal with dominant tonal components. Therefore an efficient frame interpolation method is designed to accurately estimate the phase angle and the magnitude of the MDCT-MDST coefficients of the lost frame. For the noise-like signals without overwhelming tonal components, a modified shaped-noise insertion is proposed to improve the audio perception. Both objective and subjective test results show that the proposed algorithm provides better performance than the existing ones for both music and voiced speech signals. (C) 2019 Elsevier Ltd. All rights reserved.