Wideband speech coding with toll quality based on IA-model

We propose an instantaneous amplitude (IA) based model for speech signal representation. This can avoid the difficulty in dealing with the time-varying phases and allows us to perform an optimization procedure easily such that the synthetic signal can be made as close to the original one as possible. A simplified frequency picking algorithm is derived to shorten the processing time while still maintaining the quality of the synthetic speech. Experiments show that the synthetic speech with the developed technique is of toll quality and almost perceptually indistinguishable from the original speech. Initial work on the coding of the parameters, for a 16 kHz sampled speech, for the IA model is done and a toll quality synthesized speech at a bit rate of 40 kbps is achieved.