Time delay estimation for objective quality evaluation of low bit-rate coded speech with noisy channel conditions

The paper investigates the effectiveness of several time alignment algorithms for application to objective speech quality estimation. The alignment issue is a common problem in objective speech quality research since proper alignment is important for obtaining accurate objective scores. Tallak et al. (1992) applied selected algorithms to synthetically distorted speech. The present paper extends these results by applying the algorithms to speech processed through the Federal Standard CELP 4800 bps coding algorithm. Simulated channel conditions introduce random and burst bit errors to further degrade speech quality. Algorithm performance is gauged by applying objective quality algorithms based on cepstral and mel-cepstral distance. Correlation coefficients between objective and subjective diagnostic acceptability measure (DAM) scores are used to determine effectiveness of the delay estimators