Just been having a go with Aeriality Video Pushbroom, which is a program that works via the internet and converts aerial videos into a sort of stitched orthographic image or sweep. You need a video that is pointing straight down for it to work properly. I could only find some old footage of Selby in Yorkshire pointing straight down that was taken from a plane bobbing about all over the place, so I used Warp Stabilizer on it first to get this image. I'll do a proper video with this in mind on a quadcopter and brushless gimbal next to get better results. I wasn't sure about Aeriality Video Pushbroom at first, thinking you may as well take photos and stitch them together, which is true if you want a really hi res image, but I think I can see a use in its simplicity. Check it out here: https://www.aeriality.io/ it's free to use, you get 3 video credits per month but you can use 1 credit on the same video as many times as you like, so you could make lots of different 'sweeps' from one video.