1. A method for automatically segmenting a desired region in a digital mammogram image from undesired regions, comprising the steps of: normalizing the brightness values of the pixels in said digital mammogram image to produce a normalized image; selecting a seed pixel in said normalized image; region growing said normalized image starting from said seed pixel to produce a region-grown mask; closing holes in the region-grown mask to produce a closed mask; eroding the closed mask to produce an eroded mask; and dilating the eroded mask to produce a dilated mask.