A method for automatically detecting and tracking the contour of an image
that uses a class of filters, obtained from the first order absolute
central moment. The method provides the steps of filtering a starting
image through the absolute central moment e(n,m) of the intensity of a
pixel of the image, being n and m the coordinates of each pixel, where
the absolute central moment is obtained with the following steps:
determining for each n,m the local mean calculated in a neighborhood
about a pixel of coordinates n,m of the starting image, thus obtaining a
first filtered image; determining for each n,m the sum of the absolute
differences between the intensity of a pixel of coordinates n,m of the
first filtered image and the intensity of all the pixels contained in a
neighborhood about a pixel of coordinates n,m of either the starting
image or a second filtered image obtained from the starting image.