The present invention is a method and system for detecting scene events in an imaged sequence by analysis of occlusion of user-defined regions of interest in the image. The present invention is based on the multi-scale groups of nearby pixel locations employing contrast functions, a feature that is invariant to changing illumination conditions. The feature allows the classification of each pixel location in the region of interest as occluded or not. Scene events, based on the occlusion of the regions of interest, are defined and subsequently detected in an image sequence. Example applications of this invention are automated surveillance of persons for security, and automated person counting, tracking and aisle-touch detection for market research.