UIImageWriteToSavedPhotosAlbum not saving

Question

I'm trying to save an image that is currently in my image view to the Camera Roll. The image I'm trying to save shows up perfectly in the image view, via [mainImage setImage:outputImage]; However, when I try to press the button that saves the image:

- (IBAction)saveImage:(id)sender {

    UIImageWriteToSavedPhotosAlbum([mainImage image], self, @selector(image:didFinishSavingWithError:contextInfo:), nil);

}

-(void)image:(UIImage*)image didFinishSavingWithError:(NSError *)error contextInfo:(void*)contextInfo{
    NSLog(@"%@", [error localizedDescription]);
}

The camera roll is empty. I'm using iOS7 simulator. Any help would be appreciated!

EDIT: The Assertion doesn't say anything either.

~Carpetfizz

Take advantage of the rest of the parameters to `UIImageWriteToSavedPhotosAlbum`. The selector that is called has an error parameter you can look at to see why it is failing. — rmaddy, Nov 11 '13 at 20:06
Has the app ever prompted you for permission to access your photos? You can check using [ALAssetsLibrary authorizationStatus] to see if the app has permission. — ryan cumley, Nov 11 '13 at 20:29
Yes, it asked for my permission, and it's enabled in the Privacy tab. — Carpetfizz, Nov 11 '13 at 23:52
It's absolutely late, but for anyone having the same issue, refer to https://stackoverflow.com/a/46396718/7113238 — Lawliet, Sep 25 '17 at 02:18

jason z · Answer 1 · 2020-02-24T15:37:31.533

This took me a while to figure out...

I am not exactly sure why, but if the UIImage you are trying to save is backed by a CIImage (i.e. image.cgImage == nil), UIImageWriteToSavedPhotosAlbum will oddly successfully complete with a nil error object in the completion handler, but nothing will show up in photos.

If this is the case, you can convert the UIImage's CIImage to a CGImage (Swift 4.1):

// this could also be made into an extension
func cgImage(from ciImage: CIImage) -> CGImage? {
    let context = CIContext(options: nil)
    return context.createCGImage(ciImage, from: ciImage.extent)
}

Then convert back to a UIImage (these two steps can be combined):

guard let ciImage = image.ciImage else { return }
guard let cgImage = cgImage(from: ciImage) else { return } // the above function

let newImage = UIImage(cgImage: cgImage) // ready to be saved!

I hope this solution can save someone the aggravation that this problem caused me .

Thanks! This helped me fix my issue. `guard let cgImage = cgImage(from: cgImage)` should be `guard let cgImage = cgImage(from: ciImage)` — Kushagra, Feb 24 '20 at 04:36

score 1 · Answer 2 · answered Apr 11 '14 at 06:14

I had a similar problem and searched for the answer. Though I am not sure it's exact the same cause, I hope this can give you a little insight.

My suggestion is to check [mainImage image]. It might return nil even it shows up perfectly in image view.

In my case, I should use info[UIImagePickerControllerOriginalImage] instead of info[UIImagePickerControllerEditedImage], which returns nil and that's why it was never saved.

UIImageWriteToSavedPhotosAlbum not saving

2 Answers2