A method for comparing a query video and a target video includes partitioning frames of the query video and frames of the target video into blocks and calculating the mean intensity value for each block. A plurality of query time series is produced for the query video, each query time series representing temporal variation in mean intensity value for blocks from the same location in different frames of the query video. A plurality of target time series is produced for the target video, each target time series representing temporal variation in mean intensity value for blocks from the same location in different frames of the target video the query time series and the target time series are used in determining if alignment exists between the query video and the target video.