BlurCI.mm

- (UIImage *)blurryImage:(UIImage *)image 
           withBlurLevel:(CGFloat)blur {
    CIImage *inputImage = [CIImage imageWithCGImage:image.CGImage];
    CIFilter *filter = [CIFilter filterWithName:@"CIGaussianBlur"
                         keysAndValues:kCIInputImageKey, inputImage,
                                       @"inputRadius", @(blur), 
                                       nil];
    
    CIImage *outputImage = filter.outputImage;
    
    CGImageRef outImage = [self.context createCGImage:outputImage 
                                   fromRect:[outputImage extent]];
    return [UIImage imageWithCGImage:outImage];
}