Keynote lecture 2: “Video synopsis”

Summary form only given. Surveillance video is practically never used. There are claims that 0.5% of the video is watched, but the true number is probably much smaller. The reason is clear: There are too many hours of surveillance video for people to watch. Most attempts to deal with the overflow of surveillance video involve the development of automatic video understanding: object recognition and activity understanding. Video Synopsis is complementary to video understanding. After objects are detected by background subtraction, video synopsis changes the time of display of each object such that more objects are "packed" into a shorter time. The resulting video is a shorter summary of the original video, where the objects are shown more densely than in the original video. While video synopsis can reduce, on the average, an hour of video into a minute, the synopsis loses causality: Objects that appear together in the original video may appear at different time in the synopsis, and vice versa. The combination of video synopsis and video understanding is expected to give the maximum benefit. As video understanding is still not fool proof, people need to examine its results. Since the video showing all objects of interest will be too long, video synopsis is an excellent tool to display efficiently the results of video understanding, for video examination and even for training classifiers.