Different images for same ALAssetsLibrary asset?

Question

I get an image from the ALAssetsLibrary using:

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

The image in the info dictionary has a format of kCGImageAlphaNoneSkipLast and kCGBitmapByteOrderDefault.

Later, for example when the app is relaunched, I use the referenceURL to get that same image. This time it has a format of kCGImageAlphaNoneSkipFirst and kCGBitmapByteOrder32Little.

Normally this doesn't seem to be an issue as the UIImage that results from either is handled correctly by UIImageView and other UIKit methods. However, I also send this image to a GLView which in the case of the image from the picker, ends up with the wrong tint as all blues and red values have been swapped (I can correct it by swapping the R and B bytes).

I don't know if this is a bug or whether I am doing something wrong. I'd appreciate if someone could tell me why this is happening and what the workaround is.

Here is the code for each of the two methods I use to get the image:

ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
[library assetForURL:referenceURL resultBlock:^(ALAsset *anAsset) {
    CGImageRef cgImage = anAsset.defaultRepresentation.fullResolutionImage;
    CGBitmapInfo info = CGImageGetBitmapInfo(cgImage);
    int alphaInfo = info & kCGBitmapAlphaInfoMask;
    int byteInfo = (info & kCGBitmapByteOrderMask) >> 12;
    CGImageAlphaInfo otherAlpheInfo = CGImageGetAlphaInfo(originalImage.CGImage);

// I'm seeing:
// alphaInfo:  6 (kCGImageAlphaNoneSkipFirst)
// byteInfo:   2 (kCGBitmapByteOrder32Little)
// otherAlphaInfo: 6 (kCGImageAlphaNoneSkipFirst)

} failureBlock:^(NSError *error) {
    originalImage = nil;
    thumbnail = nil;
}];

Using the - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info method:

mediaURL = info[@"UIImagePickerControllerMediaURL"];
referenceURL = info[@"UIImagePickerControllerReferenceURL"];
originalImage = info[UIImagePickerControllerOriginalImage];
if (originalImage) {
        CGBitmapInfo info = CGImageGetBitmapInfo(originalImage.CGImage);
        int alphaInfo = info & kCGBitmapAlphaInfoMask;
        int byteInfo = (info & kCGBitmapByteOrderMask) >> 12;
        CGImageAlphaInfo otherAlpheInfo = CGImageGetAlphaInfo(originalImage.CGImage);
// I'm seeing:
// alphaInfo:  5 (kCGImageAlphaNoneSkipLast)
// byteInfo:   0 (kCGBitmapByteOrderDefault)
// otherAlphaInfo: 5 (kCGImageAlphaNoneSkipLast)
}