| Abstract | Development of various multimedia applications hinges on the availability of fast and e cient storage, brows-ing, indexing, and retrieval techniques. Given that video is typically stored e ciently in a compressed format, if
we can analyze the compressed representation directly, we can avoid the costly overhead of decompressing and
operating at the pixel level. Compressed domain parsing of video has been presented in earlier work where a
video clip is divided into shots, subshots, and scenes. In this paper, we describe key frame selection, feature
extraction, and indexing and retrieval techniques that are directly applicable to MPEG compressed video. We
develop a frame-type independent representation of the various types of frames present in an MPEG video in
which all frames can be considered equivalent. Features are derived from the available DCT, macroblock, and
motion vector information and mapped to a low-dimensional space where they can be accessed with standard
database techniques. The spatial information is used as primary index while the temporal information is used to
enhance the robustness of the system during the retrieval process. The techniques presented enable fast archiv-
ing, indexing, and retrieval of video. Our operational prototype typically takes a fraction of a second to retrieve
similar video scenes from our database, with over 95% success.
|
