How do I access video output capabilities on iOS?

Applications such as Netflix have the abili开发者_Python百科ty to play video out of the dock connector when the video connector is hooked up. Do applications have the ability to put arbitrary data on video out? Or is the video player the only component on iOS that can do so? If the former is possible, how can my app access video output?

To draw to video out, place a window on the screen returned by [[UIScreen screens] objectAtIndex:1];. Call window.screen = theScreen on a window you have already created to assign it to the screen "theScreen".