Question

I want to ask that i am using core image and applying some filter is used this filter

filter = [CIFilter filterWithName:@"CIVignette" 
                                  keysAndValues: kCIInputImageKey, beginImage, 
                        @"inputIntensity", [NSNumber numberWithFloat:0.8], nil];
    CIImage *outputImage = [filter outputImage];

but i wan to know that how i implement other filters i tried but app crashes so i want to apply like these filters which is built in i chech using log

    CISourceOutCompositing,
    CISourceOverCompositing,
    CIStraightenFilter,
    CIStripesGenerator,
    CITemperatureAndTint,
    CIToneCurve,
    CIVibrance,
    CIVignette,
    CIWhitePointAdjust

Now i want to apply these filters. Which methods i should use?

Answer 1

Some, but not all of those filters aren’t available on iOS. It took me a while to notice that, too.

If you look at:

https://developer.apple.com/library/mac/#documentation/graphicsimaging/reference/CoreImageFilterReference/Reference/reference.html

The filters that work in iOS5 will say “Available in Mac OS X v10.4 and later and in iOS 5.0 and later.”, but a lot of them just say “Available in Mac OS X v10.4”. If you try and chain multiple CoreImage filters, and one of them isn’t available, you’ll get no result back from one of the filters. The CoreImage behavior when a filter isn’t available is to return nil.

As a side note, GPUImage (https://github.com/BradLarson/GPUImage) may do what you’re looking for. It can apply a filter to a UIImage or alter a live stream from the camera, and it’s compatible with iOS4, if that matters.