TIFF and LibTiff Mail List Archive


2000.01.25 22:10 "(Re:) tiff2ps: G4 compression in PostScript", by Stanislav Brabec
2000.01.25 13:29 "libtiff: bugreport (many bugs)", by Stanislav Brabec
2000.01.25 15:42 "Re: libtiff: bugreport (many bugs)", by Chris Hanson
2000.01.25 16:17 "Re: libtiff: bugreport (many bugs)", by Michael L. Welles
2000.01.28 07:39 "Re: libtiff: bugreport (many bugs)", by Tom Lane
2000.01.26 00:20 "[Fwd: (Re:) tiff2ps: G4 compression in PostScript]", by Helge Blischke

2000.01.25 13:29 "libtiff: bugreport (many bugs)", by Stanislav Brabec

Hallo tiff developers,

Testing libtiff I have found there many bugs and problems:


Configuring sed script is buggy. It works for old GNU sed, but not, for example, for GNU sed 3.02.80. Replacing of empty string is bad idea. fix: filter configure by following sed script :-) s:/@:s;@:;s:/s;;:;:


It produces inapropriate shrinking of contrast range (white is not converted to white, but to about 95% grey)

-- tiff2ps -2 produces completely invalid result for CMYK tiffs (although tiff2ps -1
   returnc correct result).
-- tiff2ps -2 produces potentially invalid files for G3/G4 compression
   (these files are accepted by latest GhostScript, but not for _any_
   Adobe licensed RIP (there these files fails).

    CAN ANYBODY HELP WITH THIS PROBLEM? I have tried contact Adobe
 support to obtain detailed specification of G4 compression developer
 without result. Peter Deutsch, author of ghostscript, but
 different code, so testing on gs will not help.used

-- ditto for DCT/progressive. PostScript Language Reference Manual

   doesn't explicitly say anything about progressive DCT compressioin,
   but the compression isn't supported nor by Adobe nor Aladdin gs.
   So it needs either data re-encoding or at least warning message.

-- %% comments are invalid DSC (BeginData _requires_ data type and length) -- I am not sure, if deadzone code have to do anything in eps mode

-- cosmetical trouble: first line of data is shorter

forgotten to update it for 3.5.x docs

configure stuff:

linux have since late 1996, only old distribution tested in libtiff. Also dll versioning part is strange and generated bad library version name. It depends on setting ALPHA version.


There is no simple way to edit resolution and image comment.

install stuff:
it creates empty "/". Why?

And note to LZW (especially note in TODO):


LZW re-enabling kit is not complete/buggy/insufficient. There is sed fix filter: # fix messages and warn about license sedfile "s/no longer supported by default due to Unisys patent enforcement/needs US license from Unisys/" */*.c sedfile "s/is no longer implemented due to Unisys patent enforcement/needs US license from Unisys/" */*.c # un-fail on LZW

sedfile "/LZW/,/}/s/TIFFError(tif->tif_name,/fprintf(stderr, /;/LZW/,/}/s/Unisys/&\\\\n/" libtiff/tif_compress.c # re-enable lzw by default

sedfile "s/\\(uint16.*compression.*=.*COMPRESSION_\\)PACKBITS/\\1LZW/" tools/*.c

Please, don't delete

it from tools; mark it by #ifdef instead. It is legal to keep the code there. (and simplifies additional adding of lzw code).

The same note applies to tiff/tif_dir.c and libtiff/tif_compress.c, where code was removed (errorred), instead of #ifdef'ing

Stanislav Brabec