1. Video Databases What are it uses? –Sports –Surveillance How do we query it? –Mosaic-based Query Language

2. A Mosaic-based Query Language for Video Databases A visual language for content-based querying of video shots Mosaics allow the representation of the entire content of a shot in a single image The language enables the specification of queries, encompassing both motion and visual features Features of camera, object, and background contained in a shot, which are possible query attributes, are all condensed into the mosaic image

3. The main idea underlying mosaic images of video shots is that of providing a synthetic representation of the shot’s content by eliminating redundancy: Mosaic images provide a comprehensive overview of different camera movements occurred during the shot. Different combinations of pan, tilt, zoom, and rotation, result in different shapes for mosaic images

4. The primitive components of our visual query language include: –camera frame –object reference –Background There are two operators to form sentences or queries: –Concatenation –Composition

5. Prototype of user interface is written in Java and creates a XML-query:

6. Previous queries can be re-edited and refined Shots from query results can be used as starting points for a new query