How do I improve contrast, and reduce noise of a black and white video and then overlay the frames?

Hi, I am new to Matlab and I am trying to write a program that apparently is not easy. I am hoping someone can help me, maybe piece by piece. I have video of the night sky, with a black and white camera. I am trying to match the stars in the video with a starmap. The problem is that in any one frame there is too much noise to pick out the stars and map them. I am trying to create a program that will process the video frame by frame, increase the contrast and decrease the noise, and then overlay all the frames on top of one another so that I can pick out the stars and match them up to a starmap. Does anyone have any ideas on how to do this?

Thanks