2018.11.10 19:41 "Re: [Tiff] Libtiff will be released soon", by Kemp Watson

I’ve sent emails to Adobe support, no responses, several times over the last year.

Leonard Rosenthol, here on the list, is with Adobe on the PDF team, and has asked internally as it’s not his wheelhouse.

I’ve asked Dave Urbanic at Zoomify to try via his buddy Pete Falco at Adobe, nothing came of that.

Really, if Adobe’s not going to maintain TIFF, they should give up ownership of the standard, or at least admit they want it to die… heck, they don’t even host a copy of the standard any more. The standard says the standard is published at

https://www.adobe.com/Support/TechNotes.html

and

ftp://ftp.adobe.com/pub/adobe/DeveloperSupport/TechNotes/PDFfiles

Both are 404/gone.

Interestingly, I just read the spec again; here’s the part about tag registration:

An organization might wish to store information meaningful to only that organi- zation in a TIFF file. Tags numbered 32768 or higher, sometimes called private tags, are reserved for that purpose.

Upon request, the TIFF administrator (send email to devsup-person@adobe.com) will allocate and register one or more private tags for an organization, to avoid possible conflicts with other organizations. You do not need to tell the TIFF ad- ministrator what you plan to use them for, but giving us this information may help other developers to avoid some duplication of effort. We will likely make the tag database public at some point.

Private enumerated values can be accommodated in a similar fashion. For ex- ample, you may wish to experiment with a new compression scheme within TIFF.

Enumeration constants numbered 32768 or higher are reserved for private usage.

Upon request, the administrator will allocate and register one or more enumerated values for a particular field (Compression, in our example), to avoid possible conflicts.

Tags and values allocated in the private number range are not prohibited from being included in a future revision of this specification. Several such instances exist in the current TIFF specification.

Do not choose your own tag numbers. Doing so could cause serious compatibility problems in the future. However, if there is little or no chance that your TIFF files will escape your private environment, please consider using TIFF tags in the “reusable” 65000-65535 range. You do not need to contact Adobe when using numbers in this range.

That’s not how the registries worked in practice, but I personally have never emailed devsup-person@adobe.com.

Kemp

From: "tiff-bounces@lists.maptools.org" <tiff-bounces@lists.maptools.org> on behalf of Larry Gritz <lg@larrygritz.com>

I know there's a good chance that all the right things have been done, but can somebody please summarize the history of attempted communications with Adobe on the matter of the tag registry -- specifically which people have been contacted and what the replies have been?

I have a few ideas for how to make progress on this but I don't want to make any assumptions that they haven't been tried before.

--
Larry Gritz

lg@larrygritz.com<mailto:lg@larrygritz.com> / lg@imageworks.com<mailto:lg@imageworks.com>