EUROSPEECH '89

The inclusion of a polezero vector predictor in the backward loop of an AVPC coder[1] is approached . We hope to reach the same profit shown by the polezero predictor in the ADPCMCCITT standard. By using a VLMS transversal algorithm the obtained behaviour does not outperform the allpole scheme. We argue it is due to the dependence on the eigenvalues spread of the LMS perfomance. By using an orthogonalizedlattice structure this problem can be overcame. The zeros term shows an aditional advantage consisting in the removal of the artificial correlation introduced by the pole term of the predictor. This leads to a better profit of the VQ ability and a good coding perfomance of the whole system.
Bibliographic reference. MasgrauGomez, E. / RodriguezFonollosa, J. A. / MorenoBilbao, A. (1989): "Including zeros in the backward adaptive predictor of AVPC coders", In EUROSPEECH1989, 25052508.