Recently I have been writing software designed to take imagery for astronomy applications, and it turns out astronomy types love FITS. FITS is great, but the C libraries available are not. If you live in Python land, astropy does a good job at hiding the ugliness from you. But if you live in C/C++ land, you are in for some pain.
With this being said, I created OpenCVFITS. It is pretty easy to work with, and gives people using OpenCV a way to read and write multiple images from a single FITS file. It also provides some functionality to writing metadata to each image in a flexible way.
Any comments, suggestions, and updates are very welcome!