Processing image with CUDA

I know that my question may be a bit stupid but here is my problem.
I am starting with CUDA programming and I have to work on images (creating filtering algorithms etc…). But I do not know how to charge an image to work on in my program, so how do I do to define an image (which libraries, what to include etc…)

I have never work on processing pictures before ^^

( I work with cuda 7.5 on windows 10)

thanks for helping

example : capture frame from Web-camera, then transform color->sepia using OpenCV & CUDA