Removing Shadows from Images

Illumination conditions cause problems for many computer vision algorithms. Inparticular, shadows in an image can cause segmentation, tracking, or recognition algorithms to fail. In this paper we propose a method to process a 3-band colour image to locate, and subsequently remove shadows. The result is a 3-band colour image which contains all the original salient information in the image, except that the shadows are gone. We use the method set out in 1 to derive a 1-d illumination invariant shadow-free image. We then use this invariant image together with the original image to locate shadow edges. By setting these shadow edges to zero in an edge representation of the original image, and by subsequently re-integrating this edge representation by a method paralleling lightness recovery, we are able to arrive at our sought after full colour, shadow free image. Preliminary results reported in the paper show that the method is e ective. A caveat for the application of the method is that we ...

• Type: Conference
• Year: 2002
• Where: ECCV
• Authors: Graham D. Finlayson, Steven D. Hordley, Mark S. Drew
• Keywords: 3-band Colour Image, Computer Vision, ECCV 2002, Invariant Image, Invariant Shadow-free Image, Original Image, Shadow Free Image