Mean compensation based on projection-based group delay scheme for noisy speech recognition

A mean vector compensation technique based on the projection-based group de lay scheme has been combined with a semicontinuous HMM to improve the recog nition rate in noisy environments. The proposed approach compensates the me an vector using a projection-based scale factor and the bias estimated From the training and/or testing data to balance the mismatch between different environments. Experiments show that the significant improvement in speaker -dependent, isolated word recognition was achieved by adding the projection -based scale factor and mean vector bias.