2005.12.12 23:47 "Re: [Tiff] Writing EXIF data?", by Bob Friesenhahn
Previous versions which supported TIFFTAG_EXIFIFD are very limited (as you describe), and older versions don't know anything about EXIF at all. So everything depends on what version of libtiff you are using.
OK, but, for 3.7.4, it's still not clear how you set the EXIF IFD to <binary chunk of data> --OR-- to use TIFFSetField() with EXIF tags. The 3.7.4 headers do *not* include EXIF tags, e.g, EXIF_APERTURE_VALUE (9202.H).
Maybe that is because EXIF private tag values would conflict with the public tag space?
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