This is not currently possible but is something that a lot of people want to do. Probably the best solution for you is to allow your students to upload somewhere else and provide a link to the image. Perhaps a dropbox link or similar would work.
The JS app is another solution but, as you say, this will need some development time. I have played around with this a bit and now that I am aware you want this sort of thing, I'll let you know if I get it working. I don't think it will be before easter at this point.