Provided is a video analysis (VA) method comprises calculating, by a VA apparatus, a size of each of a plurality of frames by summing sizes of a plurality of packets constituting each of the plurality of frames, analyzing, by the VA apparatus, the size of each of the plurality of frames constituting a video to determine a pattern of the sizes of the plurality of frames and determining, by the VA apparatus, whether there is a motion in the video based on the size pattern.