XP: Clever little VLC
Posted by cascadehush on September 27, 2006
One of the annoying things about the current generation of graphics cards is that they only have one overlay surface. What this means is that if you have more than one video window open, only one of them is being optimally displayed by the graphics card. In some cases, it can actually mean that some apps won’t load if another is open. Try to record a TV show whilst watching a DVD and you might see this behavior. Most TV tuner software will steal the overlay surface, even if you only want the app running in the background. For this very reason I have a separate PC purely to run my TV tuner.
I hope this situation will change one day, but I don’t hold my breath. I’ve not ever heard anyone mention it, anywhere, ever. I am reminded of the time when soundcards would only play sound from one application at a time (about a decade ago) and if one application tried to access the soundcard whilst another was using it, you would get a popup box complaining to you.
But now here is a cleaver thing. I just noticed that if you are running a video in an instance of VLC (this is on a Windows XP PC) that is not using the overlay surface, and you close another instance of VLC that was using it, then the first instance of VLC immediately starts using the overlay surface.
You can observe this behavior most easily if you have the overlay surface set to display on a specific screen of a multi-screen setup.
I’d appreciate any feedback about this type of behavior with other applications, or any gripes you might have about how overlay surfaces work and any work-arounds or tricks.
I am using a nVidia FX5200 based card. Not fancy, but it’s a nice fanless card which runs 2 monitors and a TV and is excellent for video playback.