Block transform coder for arbitrarily shaped image segments

摘要

Signal images on arbitrarily shaped supports are linearly transformed by applying a number of staged processes. The first process consists in decomposing the support into a number of sub supports which have a regular form such as square or rectangular. A linear orthogonal transformation is then applied to each sub support in the second stage and this is followed by a third stage where a regrouping by coefficients according to predetermined criteria takes place. In a final stage, there is an iteration of the transformation on the classes of coefficients formed.