A computing system processes a video recording to identify a plurality of motion events, each corresponding to a respective video segment along a timeline of the video recording. The computing system identifies at least one object in motion within a scene depicted in the video recording and stores a respective event mask for each event. The computing system receives a definition of a zone of interest within the scene. In response to receiving the definition, the computing system determines, for each motion event, whether the respective event mask of the motion event overlaps with the zone of interest by at least a predetermined overlap factor, and identifies one or more events of interest from the plurality of motion events, wherein the respective event mask of each identified event of interest is determined to overlap with the zone of interest by at least the predetermined overlap factor.