An image processing system and method for comparing two monochromic images A2 and B2 is provided. The system and method thins objects in the monochromic image B2 so as to generate a skeleton image B3, thickens the objects in the monochromic image A2 to generate a bold image A4, and overlays the skeleton image B3 with the bold image A4 so as to generate an overlaid image AB1. The system and method further thins the objects in the monochromic image A2 so as to generate a skeleton image A3, thickens the objects in the monochromic image B2 to generate a bold image B4, and overlays the skeleton image A3 with the bold image B4 so as to generate an overlaid image AB2. The system and method outputs the overlaid images AB1 and AB2 on a display screen.