Yes, keeping the model up to date is definitely an important issue. Don't forget that this also involves capturing new aerial imagery periodically. Another ap

Yes, keeping the model up to date is definitely an important issue. Don't forget that this also involves capturing new aerial imagery periodically. Another approach that may have more potential than automatically extracting 3D structure from aerial imagery is using aerial depth maps from something like LIDAR. There's a research group at USC doing this, and you can see a video describing the process here: http://graphics.usc.edu/~qianyizh/miscs/cvpr09_streaming_full.mov http://graphics.usc.edu/~qianyizh/miscs/cvpr09_streaming_ful...