Frankly, I'm not very impressed. This problem is a very very well known problem in Image Processing. Usually people call it background subtraction or the more general form is image segmentation.
There is many really well working algorithms in this field. A google search with the major research conferences (ICCV, ICIP, SIGGRAPH etc) will give you the latest and the greates of these algorithms. You'll also find good (image segmentation) work if you limit the search for csail.mit.edu.
If you want your uploader to help you, you can also go for one of the supervised image segmentation algorithms. Otherwise you'll need an unsupervised algorithm.
Given that the authors also want to detect what is in the image, this might be helpful for them:
There is many really well working algorithms in this field. A google search with the major research conferences (ICCV, ICIP, SIGGRAPH etc) will give you the latest and the greates of these algorithms. You'll also find good (image segmentation) work if you limit the search for csail.mit.edu.
If you want your uploader to help you, you can also go for one of the supervised image segmentation algorithms. Otherwise you'll need an unsupervised algorithm.
Given that the authors also want to detect what is in the image, this might be helpful for them:
http://people.csail.mit.edu/mrub/papers/ObjectDiscovery-cvpr...
This guy is also doing some great work in that field:
http://www.engr.uconn.edu/~cmli/