Best Desktop AR Library

Hi, I have a potential project where I need AR for mobile (ios and android) and standalone desktop apps for mac and pc. I have used both String and QCAR and they work well on mobile, but I have had difficulty finding clear info about the best options for the desktop versions. I need something that is likely to be compatible with all/most webcams. Does anyone have any favorites? It's not necessary that the same library work on all platforms, just that I have an option for each platform. Thanks.