2013.06.13 16:07 "Re: [Tiff] TIFF Specification Allowance for Multi-Page vs. Reduced Res 2nd IFD", by Scott Ribe

On Jun 13, 2013, at 9:52 AM, Douglas Peterson wrote:

> I have put considerable effort into understanding the proper structure for TIFFs. I've read an Intro to TIFF Creation and the NewSubFileType spec and learned to read hex (at an intro level). I have JHOVE and MAC OSX TiffUtil at my disposal. I say all this not to brag (as I'm sure I'm one of the least knowledgable members of this mailing list) but only to explain that I have tried very hard to resolve this issue on my own before appealing for help from this community.

The best source I know for doing that is "The Encyclopedia of Graphics File Formats". I say this not to suggest that you haven't yet got the knowledge you need, just giving you a pointer to a good explanation of TIFF.

We want to continue to provide TIFFs with the IFD that contains a thumbnail as some users may have incorporated the thumbnails into their workflows. But we do not want these other programs to see the TIFFs as multi-page documents.

And that's probably the root of your problem. In my experience, a lot of TIFF viewers are just really, really stupid about multi-image TIFF files.

Actually, a lot of TIFF viewers are just really, really stupid, period. For instance, a lot of them ignore the photometric sense for black-and-white images. And of those that ignore it, some assume min-is-black and others assume min-as-white, resulting in a situation where you, the TIFF writer, simply *cannot* create a black-and-white image that will display correctly on all of them.

--
Scott Ribe
scott_ribe@elevated-dev.com
http://www.elevated-dev.com/
(303) 722-0567 voice