How to Convert UIImage to CIImage and vice versa

Question

I\'m trying to get CIImage from ImageView that display on the screen.

UIImage *image = myImageView.image;

convert image

Answer 1

Here is a complete code sample that I've used in my projects.

- (UIImage *)makeUIImageFromCIImage:(CIImage *)ciImage {
    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef cgImage = [context createCGImage:ciImage fromRect:[ciImage extent]];

    UIImage* uiImage = [UIImage imageWithCGImage:cgImage];
    CGImageRelease(cgImage);

    return uiImage;
}

CIImage is basically a recipe for an image. You will run into problems if you try to directly convert from CIImage to UIImage. For example, calling

NSData * UIImageJPEGRepresentation (
   UIImage *image,
   CGFloat compressionQuality
);

will return nil.

Answer 2

func toCIImage(image: UIImage) -> CIImage {
    return image.CIImage ?? CIImage(CGImage: image.CGImage!)
}

func toUIImage(image: CIImage) -> UIImage {
    return UIImage(CIImage: image)
}