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cocoa touch - UIImageWriteToSavedPhotosAlbum working... sometimes

UIImageWriteToSavedPhotosAlbum is only working sometimes. Sometimes it works, sometimes it doesn't, exact same function.

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo {
NSLog(@"Saving image to camera roll...");
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
NSLog(@"Done!"); }

I am using a UIImagePicker controller to get the image that then calls that function.

Sometimes it saves it to the camera roll, other times it simply doesn't.

Anyone has any idea?

Thanks in advance.

Edit:

The completion method for UIImageWriteToSavedPhotosAlbum sometime returns an error of:

wait_fences: failed to receive reply: 10004003
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Hope this answer isn't too late to be helpful. I ran into exactly the same problem. As it turns out the issue is two-fold. First, the image does need to be retained before it is sent to UIImageWriteToSavedPhotosAlbum. Secondly, on pre-iPhone4 devices this function can take a loooooong time to do its thing. The fix I found was to implement a callback function. See the documentation for UIImageWriteToSavedPhotosAlbum about this. The function must be in the correct format, you can't just use any old function. In this function be sure to release the image you retained or you will leak memory. You can also use this to keep track of when images are done saving. Here is my basic code below:

    -(void)processImage:(UIImage *)image {
        [image retain];
        UIImageWriteToSavedPhotosAlbum(reconstructedImage, self, @selector(image:didFinishSavingWithError:contextInfo:), NULL);
}


    - (void)image:(UIImage *) image didFinishSavingWithError: (NSError *) error contextInfo: (void *) contextInfo {
        NSLog(@"SAVE IMAGE COMPLETE");
        if(error != nil) {
            NSLog(@"ERROR SAVING:%@",[error localizedDescription]);
        }
        [image autorelease];
    }

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