I am trying to add IPTC metadata to images using the iOS SDK and am unable to get it to work. No matter what I try, the dictionary with the IPTC metadata does not end up getting stored in the image saved to the photo library. This applies both to images to which I add IPTC metadata when originally there was none, and to images which have IPTC metadata (e.g., the original image had IPTC metadata and was sync'ed to the iOS device with iTunes). In both cases when I save the image using the ALAssetsLibrary writeImageToSavedPhotosAlbum:orientation:completionBlock: method, and then retrieve the image again, the IPTC metadata (added or modified) is not in the retrieved image.
I have seen very little if any actual code samples that deal with IPTC metadata. There are plenty of examples that deal with EXIF and GPS metadata, both of which I am able to successfully manipulate. But no luck with IPTC.
If anyone has been able to accomplish this, especially using the stock iOS SDK APIs, I'd love to know the particulars and especially see some example code fragments.
