This algorithm explores the intensity changes within a window as the window changes location inside an image. Unlike an edge, for which intensity values change abruptly in only one direction, there is a significant change in intensity values at a corner in all directions. Hence, a large change in intensity value should result when the window is shifted in any direction at the corner (with good localization); this fact is exploited in the Harris Corner Detector algorithm. It is invariant to rotation, but not to scale (that is, the corner points found from an image remain unchanged when the image undergoes a rotation transformation, but change when the image is resized). In this section, we shall discuss how to implement a Harris Corner Detector with scikit-image.