2006.08.25 15:36 "Re: [Tiff] IPTC tag", by Bob Friesenhahn
This IPTC tag discussion seems to be a lot of heat about something which can not be repaired. The horse has already left the barn. Elvis has left the building.
In GraphicsMagick we deal with the long-swapping issue by simply swapping when necessary (when TIFFIsByteSwapped() returns true). The length of the data is always assured to be evenly divisible by four. This approach seems to work.
IPTC data is found in TIFF using several different mechanisms. Photoshop stores IPTC data in its own (8BIM) chunk so the same (or different) IPTC data may appear in a TIFF a couple of times.
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/