courtesy of WWDC code examples (ios_uiimageeffects.zip)
- add files to project
- add "Accelerate" framework to "Build Phases"
- create ZGBlurView in your code
ZGBlurView *subBlurView = [[ZGBlurView alloc] initWithFrame:self.view.frame];
[self.view addSubview:subBlurView];
//should call "blur" after added to super view
[subBlurView blur];