Median Filter for ios

Question

I'm looking to apply Median Filter to a UIImage in my iOS application. Due to my company restrictions, i cannot use openGL filters.

Any ideas or current implementations would be very welcomed. Thanks.

Answer 1

Apple's Core Image framework may be your solution. To be precise, you need a subclass of CIFilter which implements a median filter. (Guess you would be interested in CIMedianFilter or have a look at the filter reference)

CIIImage *inputImage = //...

CIFilter *filter = [CIFilter filterWithName:@"CIMedianFilter"];
[filter setDefaults];
[filter setValue:inputImage forKey:@"inputImage"];

CIImage *outputImage = [filter outputImage];

To convert the CIImage to UIImage and vice versa:

CIImage *ciImage = [UIImage imageNamed:@"test.png"].CIImage;
UIImage *uiImage = [[UIImage alloc] initWithCIImage:ciImage];