1993.05.27 13:20 "modified version of xtiff.c", by Harald Lange

1993.06.21 17:51 "Re: modified version of xtiff.c", by Sam Leffler

we have used xtiff (Revision 2.0 90/12/20, actual version coming with TIFF 3.21) for displaying RGB-images (24bit) on our Sun 4/370 (32bit TAAC-Framebuffer) under X-Windows, but the result was not satisfying. A little look to the source reveal some typing errors in the index-value of the pixel_map variable, which we have corrected.

Another important change is the new name for the tagfield TIFFTAG_TRANSFERFUNCTION, which is now called TIFFTAG_COLORRESPONSECURVE.

No. These tags are not interchangeable--the new TransferFunction tag requires that you use the other new colorimetry-related tags in calculating the corrected screen pixel values. Please look at the appropriate appendix in the 6.0 spec.

Beyond that we have made the following expansions to xtiff:

  1. Show Pagenumber Tagfield if present
  2. Consider Fillorder Tagfield

FillOrder is handled by the TIFF library, so using it to set the bit-order of the data that you hand to the X code is wrong--unless you are reading raw data directly from the file (which you do not appear to be doing).

I think it is a good idea to make this corrected version available in the following TIFFLibrary Distribution. I have tried to mail these bug to Dan Sears directly, but the mail came back, because of unknown user dbs@decwrl.dec.com

Dan&Chris Sears no longer work on Unix systems. I include the last version of xtiff that they provided me in the sources I give away in the hope that someone will properly update it to use the 6.0 tags.

Sam