fast iphone screen capture

We're using UIGetScreenImage to capture 3-6 images per second and save them to disk. However, we are looking for a way to capture images at a faster rate. We've noticed some implementations that appear not to use UIGetScreenImage (we know this because they're overlaying controls in the preview that isn't captured on the image) and they're able to capture up to 15 images per second and save to disk. Is there another way to capture and save images at a faster rate开发者_Go百科 than UIGetScreenImage?

You can use quartz to render an off screen version of the view being drawn. the exact details escape me at the moment, but I believe you need to grab a different context in your view's draw method, and draw a copy to some place where you would then save it.

This doc may have more info: http://developer.apple.com/mac/library/documentation/GraphicsImaging/Conceptual/drawingwithquartz2d/dq_context/dq_context.html#//apple_ref/doc/uid/TP30001066-CH203-SW9

You can try using the ScreenCaptureView class discussed here.