that is such a subtle difference! The Micro B plug seem to fit the A slot quiet well tho, unfortunately i placed an order for Micro B adapter already 
looking at their schematic, their differences are just the shape of the plug, if it fits may as well work too . a usb adapter should have been one of the many useless adapters i got in the box ....
how did you port your openCV code? i am thinking of compiling on my desktop than a stright forward port should work, since they are all x86 ?