There is an SDK for the AVerMedia C039P USB Capture Card mentioned on a few websites, but nothing regarding its availability or downloads or even documentation on where and how to start. I've also looked on the web for a sample for you as requested in the question above but didn't find anything which means it's either impossible to do what you asked for or not supported anymore.
You can try getting help from freelancers, but I doubt it will help since no documentation or a starting point is found.