2004.12.16 20:09 "Re: [Tiff] CIELAB/ITULAB", by Joris Van Damme
So I extended the libtiff by the Decode tag and tried PhotometricInterpretation=10 (ITULAB) with the default values for Decode (taken from http://www.awaresystems.be/imaging/tiff/tifftags/decode.html). Unsurprisingly, some of the viewers refused the TIFF file but the rest showed the same wrong colors.
I misread part of this in previous reply, sorry.
Setting the tag with default values as a last resort does not have a great chance to improve any compatibility of your files in any readers. After all, readers that are ITULAB aware, are most probably either
- ignoring the tag and using the defaults anyway
- reading the tag, and thus using the same defaults
It would change something if some buggy reader was ITULAB aware in a buggy way, and nevertheless solid enought to read and respect the tag. Not very likely.
Most readers are just not ITULAB aware. If you don't actually need the TIFFs to be in that particular colorspace (understanding you correctly this time?) then convert colorspace between jpeg reading and tiff writing, thus writing out TIFFs in a much better supported space like even plain old RGB.
Joris Van Damme
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