Character format using the values \c kXMP_Char8Bit, \c kXMP_Char16BitBig, etc.
True if there is a packet wrapper, the "<?xpacket...>" XML processing instructions.
Packet length in the file in bytes, -1 if unknown.
Packet offset in the file in bytes, -1 if unknown.
Padding to make the struct's size be a multiple 4.
Packet padding size in bytes, zero if unknown.
True if there is a packet wrapper and the trailer says writeable by dumb packet scanners.