Immersive remote monitoring of urban sites

In a typical security and monitoring system a large number of networked cameras are installed at fixed positions around a site under surveillance. There is generally no global view or map that shows the guard how the views of different cameras relate to one another. Individual cameras may be equipped with pan, tilt and zoom capabilities, and the guard may be able to follow an intruder with one camera, then pick him up with another. But such tracking can be difficult, and hand off between cameras disorienting. The guard does not have the ability to continually shift his viewpoint. More over current systems do not scale up with the number of cameras. The system becomes more unwieldy as cameras are added to the system. In this paper, we will present the system and key algorithms for remote immersive monitoring of an urban site using a blanket of video cameras. The guard monitors the world using a live 3D model, which is constantly being updated from different directions using the multiple video streams. The world can be monitored remotely from any virtual viewpoint. The observer can see the entire scene from far and get a bird's eye view or can fly/zoom in and see activity of interest up close. A 3D-site model is constructed of the urban site and used as glue for combining the multiple video streams. Moreover each of the video cameras has smart image processing associated with it, which allows it to detect moving and new objects in the scene and recover their 3D geometry and pose of the camera with respect to the world model. Each video stream is overlaid on top of the video model using the recovered pose. Virtual views of the scene are generated by combining the various video streams, the background 3D model and the recovered 3D geometry of foreground objects. These moving objects are highlighted on the 3D model and used as a cue by the operator to direct his viewpoint.