A computer-assisted method for producing a space time summary for one or more original videos includes automatically recognizing a key element in an original video, extracting pixels related to the key element from a series of video frames of the original video, producing a video bit comprising a series of video frames comprising the pixels and audio information extracted from the original video, wherein at least one video frame of the video bit is formed by a subset of pixels of the corresponding video frame in the original video, automatically displaying a plurality of video bits in a user interface, wherein the plurality of video bits are extracted from one or more original videos, and provide a space time summary for the one or more original videos, and allowing two of the plurality of video bits to be played simultaneously with audio and motion in the user interface.