PanoramaExcerpts: extracting and packing panoramas for video browsing

Browsing is a fundamental function in multimedia systems. This paper presents PanoramaExcerpts a video browsing interface that shows a catalogue of two types of video icons: panoramic and keyframe icons. A panoramic icon is synthesized from a video segment taken with camera pan or tilt, and extracted using a camera operation estimation technique. A keyframe icon is extracted to supplement the panoramic icons; a shot-change detection algorithm is used. A panoramic icon represents the entire visible contents of a scene extended with camera pan or tilt, which is difficult to summarize using a single keyframe. For the automatic generation of PanoramaExcerpts, we propose an approach to integrate the following: (a) a shot-change detection method that detects instantaneous cuts as well as dissolves, with adaptive control over the sampling rate for efficient processing; (b) a method for locating segments that contain smooth camera pans or tilts, from which the panoramic icons can be synthesized; and (c) a layout method for packing icons in a space-efficient manner. We also describe the experimental results of the above three methods and the potential applications of PanoramaExcerpts.