2007.01.17 22:18 "Re: [Tiff] Elevation Data", by Bob Friesenhahn

>> I suspect that the discussion of this obscure topic has gone on longer >> than most list subscribers are interested in.

>
> TIFF is an open file format. The ambition of open file formats is

interchange.

> This is the TIFF mailing list.

I did not mean to offend, but the discussion was unlikely to result in a useful decision.

The TIFF specification is as old as dirt. Instead of attempting to intuit the use of old tags (over which we have no control at all) it seems better to define new tags and get them ratified as part of a new specification so that when the new tags are present, they may be relied upon.

The discussion up to now has made it very clear that there is little that can be done to salvage the existing tags.

If the new tags are similar to what is used in OpenEXR (I have no idea what OpenEXR does) or some other significant use of floating point data, then more birds can be killed with one stone. I suspect that we may be able to obtain some specification support from Adobe if the tags are similar to something in OpenEXR since Adobe's recent floating point efforts in TIFF (for Photoshop CS2) are to support data imported from OpenEXR.

Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/