Intrinsic Image Based Moving Object Cast Shadow Removal in Image Sequences

The goal in this paper is to detect and remove shadows of moving objects in colour image sequences. The method works by deriving the shadow edges of a 3-band colour image, integrating edge information temporally in the image sequence, and subsequently removing these shadows by a method paralleling reflectance recovery by entropy minimisation. The method incorporates background subtraction information and extensive edge-linking morphology to detect superior shadow edges. This integration has greatly increased the scope of applicability and brought about significant enhancements in the recovered shadow-free images and the time of processing. Shadows in the frames of image sequences are shown to be significantly attenuated. At present the implementation runs about 4 frames per second and can serve as a good utility in improving the performance of high level algorithms in scene monitoring.