Fast blur on iOS

Question

I\'m running into trouble trying to blur part of the screen in my iOS app. See image for better idea of what I\'m trying to do.

Answer 1

You might try the Apple Core Image Filter (CIFilter) set of routines. They require iOS 5, so you might not be able to use them.

I am not sure if it is faster then the methods you have tried, but I have used it in projects in the past, and it works really well. If you can grab the part of the screen you want to make blurry, put that into an image, pass it through a filter, and then re-display it at the appropriate place on the screen, that should work.

I used the filters to change the colors of an image in real-time, and it worked well.

http://developer.apple.com/library/ios/#DOCUMENTATION/GraphicsImaging/Reference/QuartzCoreFramework/Classes/CIFilter_Class/Reference/Reference.html