Having a dig through Metadata keys & values and need more info. First of all there are 2 dataTypes, first is AVMetadataItem.dataType & second .extraAttributes dictionary, and the second is number value. Most common numbers are 1 21 13 but at the moment mean next to nothing, need a reference table or some sort ?
13 & 14 are JPEG or PNG and the string dataType value is com.apple.metadata.datatype.JPEG or com.apple.metadata.datatype.PNG. I want to compare against NSImage.imageTypes which is public.jpeg or public.png, how can I get them to match up ? (hope that makes sense)