Hi, I'm new to the forum, and I was wondering if anyone here has expertise in computer vision? I have a few mundane questions as well as some significant ones, and forgive me, but my knowledge of programming graphics is pretty limited.

(Easy question): how can I convert an image file, say a jpeg into a matrix of integral values in c++?

(Hard question): does anyone know a good algorithm for determining whether a corner in an image is concave or convex?
I've figured that if only three edges come together with less than 180 degrees (like an arrow shape) then it's a convex corner... but with a corner that's shaped like a Y it can be either. Any thoughts?

Thanks for your help.