1. An automated method for analyzing target contrast features in a digital image of a biological sample, comprising: partitioning at least a portion of the digital image into search areas of similar size with the target contrast features; locating a first pixel within each of the search areas based on pixel intensity level; locating a test region around each of the first pixels, wherein the test regions and the target contrast features are similar in size; and calculating intensity localization values for the test regions by comparing, for each test region, the intensity of a plurality of interior pixels located within the test region to the intensity of a plurality of perimeter pixels located at the perimeter of the test region.