Image enhancement by morphological pyramid decomposition and modified reconstruction

An algorithm for multiresolution pyramid decomposition is described. At each stage, the smoothed ("lowpass") image is obtained by combining morphological grayscale opening and closing. Using this technique, we avoid the systematic bias of traditional approaches, as illustrated by an example. As our application, we perform image enhancement by modifying the reconstruction scheme using a morphological edge detector. The processing scheme offers a method for edge-preserving noise (speckle) suppression, in which only a minor number of multiplications is required.