iOS 7 introduced the UIBlurEffect, which was very cool, but not particularly controllable. Here’s a more granular approach discovered at work, but sadly, not used.
// *************************************************************************************************
#pragma mark
#pragma mark - helper methods
// this helper method processes a Gaussian Blur for image.
// We tried the Apple UIBlurEffect but not granular enough controls.
// Usage in viewDidLoad (assuming you want the blur to appear immediately)
// self.blurryProductImageView.image = self.productImage;
//
// // more blurr => increase the number of loops
//
// for (int i=0; i < 10; i++) {
// self.blurryProductImageView.image = [self imageWithGaussianBlur:self.blurryProductImageView.image];
// }
// self.blurryProductImageView.alpha = 0.5;
- (UIImage *)imageWithGaussianBlur:(UIImage *)image {
float weight[5] = {0.2270270270, 0.1945945946, 0.1216216216, 0.0540540541, 0.0162162162};
// Blur horizontally
UIGraphicsBeginImageContext(image.size);
[image drawInRect:CGRectMake(0, 0, image.size.width, image.size.height) blendMode:kCGBlendModePlusLighter alpha:weight[0]];
for (int x = 1; x < 5; ++x) {
[image drawInRect:CGRectMake(x, 0, image.size.width, image.size.height) blendMode:kCGBlendModePlusLighter alpha:weight[x]];
[image drawInRect:CGRectMake(-x, 0, image.size.width, image.size.height) blendMode:kCGBlendModePlusLighter alpha:weight[x]];
}
UIImage *horizBlurredImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// Blur vertically
UIGraphicsBeginImageContext(image.size);
[horizBlurredImage drawInRect:CGRectMake(0, 0, image.size.width, image.size.height) blendMode:kCGBlendModePlusLighter alpha:weight[0]];
for (int y = 1; y < 5; ++y) {
[horizBlurredImage drawInRect:CGRectMake(0, y, image.size.width, image.size.height) blendMode:kCGBlendModePlusLighter alpha:weight[y]];
[horizBlurredImage drawInRect:CGRectMake(0, -y, image.size.width, image.size.height) blendMode:kCGBlendModePlusLighter alpha:weight[y]];
}
UIImage *blurredImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//
return blurredImage;
}
Amazing feature, that sadly, my employer decided to take it out of the app.
