A program for generating a significant video stream causes a computer to function as coding parameter extraction means for extracting a coding parameter of each macroblock for each frame from an original video stream, macroblock selection means for selecting a significant macroblock that has a coding parameter satisfying a predetermined condition, and significant video stream generation means for generating a significant video stream in which frames of the original video stream temporally synchronized with the frames of the coding parameter in the significant macroblocks are combined in time series.