Freeze? I think it just causes severe slowdowns. I think once this opengl for vita is finished and they implement it into retroarch, it will be past us.you can do everything but post process. so you can change hue or colorize, add pre-cooked light or shadow. you couldn't actively blend or blur but you could add a haze. So it's like limited filtering. There is video filters besides the overlays but they are currently broken and cause retroarch to freeze.