2005.12.13 20:27 "Re: [Tiff] Writing EXIF data?", by Joris Van Damme
It has been my experience that all the offsets inside the EXIF IFD are infact relative to its start.
An EXIF IFD is an IFD. Take a look at the TIFF specification, part I, section 2, and/or the TIFF FAQ, question 3, http://www.awaresystems.be/imaging/tiff/faq.html#q3.
TIFF never contains offsets other then offsets from the start of the TIFF file. That's one of the most primary rules in TIFF. EXIF does not break this. MakerNote does break some of these rules, and that's one of the reasons normal TIFF handling does get into trouble with MakerNote data.
Joris Van Damme
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