US Patent 8437556 Shape-based object detection and localization system

Described is a system for identifying a concealed object of interest. The system is initialized by receiving an image in grayscale. The image is processed image to identify feature rich regions, which are identified as a binary mask describing edge pixels and non-edge pixels. A set of edge pixels are then randomly sampled. An object detector function is then used on the set of edge pixels to determine if an object of interest is present in the set of edge pixels.