giftrans

NAME
  giftrans - transform gif from gif87 to gif89, making one
  color transparent

SYNOPSIS
  giftrans [options] [-o filename] filename

DESCRIPTION
  giftrans converts any GIF file into a GIF89a.  Allows for
  setting the transparent or background color, changing
  colors, adding or removing comments. Also code to analyze
  GIF contents.

OPTIONS
  -h   Print short help on stdout.

  -t   Specify the transparent color

  -T   Index of the transparent color is the background color
	   index

  -B   Specify the transparent color's new value

  -b   Specify the background color

  -g   Change a color in the global color table

  -c   Add a comment

  -C   Remove old comment

  -l   Only list the color table

  -L   Verbose output of GIFs contents

  -V   Verbose output while converting

  -o   Redirect stdout to a file

  -e   Redirect stderr to a file

  Colors may be specified as index, as rgb.txt entry or in the
  #rrggbb form.

EXAMPLE
  To convert the white background of a gif file to
  transparent, use

	   giftrans -t #ffffff file.gif > transparentfile.gif

BUGS
  This program has been tested on a HP9000/720 with HP-UX
  A.08.07 In this environment, neither lint -u nor gcc -Wall
  produce any messages.  If you encounter any errors or need
  to make any changes to port it to another platform, please
  contact me.

  Known bugs:

	   -B flag won't work if there's an Extension between the
	   Global Color Table and the Image Descriptor (or Graphic
	   Control Extension). If -V has been specified, a Warning
	   Message will be displayed.  Will be fixed in 2.0

	   Always outputs GIF89a. Shouldn't do this if version is
	   newer.

	   -D option may output changed data instead of original
	   data, use with caution, best only with then -L option.

COPYRIGHT
  Copyright (c) 24.2.94 by Andreas Ley <ley@rz.uni-
  karlsruhe.de>

  Permission to use, copy, modify, and distribute this
  software for any purpose and without fee is hereby granted,
  provided that the above copyright notice appears in all
  copies. This software is provided "as is" and without any
  express or implied warranties.

VERSION HISTORY
  Version 1.11 - 21.7.94
	   Moved Plain Text Extension to the Extensions section
	   where it belongs
	   Accept Unknown Extension Labels
	   Incorporated MS-DOS port by enzo@hk.net (Enzo
	   Michelangeli)
	   Added -o and -e options to redirect stdout and stderr
	   Added -D debug flag

  Version 1.10.2 - 22.6.94
	   Support for -DRGBTXT flag

  Version 1.10.1 - 21.6.94
	   Different rgb.txt file FreeBSD/386BSD

  Version 1.10 - 19.6.94
	   Added option to change a color in the global color
	   table
	   Added option to change the color for the transparent
	   color index

  Version 1.9.1 - 7.6.94
	   Different rgb.txt files for X11 and Open Windows

  Version 1.9 - 1.6.94
	   Fixed a bug which caused color names to be rejected.

  Version 1.8 - 30.5.94
	   Accept #rrggbb style arguments.
	   Do nothing if rgb-color not found in GIF.

  Version 1.7 - 16.5.94
	   Added -l option to only list the color table.
	   Added -L option for verbose output without creating a
	   gif.  Added -b option to change the background color
	   index.
	   Display all matching color names for color table
	   entries.
	   Fixed a bug which caused bad color names if rgb.txt
	   starts with whitespace.
	   Doesn't use strdup anymore.
	   Fixed =& bug on dec machines.

  Version 1.6 - 5.4.94
	   Added color names recognition.

  Version 1.5 - 15.3.94
	   Added basic verbose output to analyze GIFs.

  Version 1.4 - 8.3.94
	   Fixed off-by-one bug in Local Color table code.
	   Added option to add or remove a comment.
	   Transparency is no longer the default.

  This man file made 9.8 from documentation in the program
  source code by Kai Nordlund (knordlun@fltxa.helsinki.fi).

THANKS
  Thanx for bug reports, ideas and fixes to

	   patricka@cs.kun.nl (Patrick Atoon)

	   wes@msc.edu (Wes Barris)

	   pmfitzge@ingr.com (Patrick M. Fitzgerald)

	   hoesel@chem.rug.nl (frans van hoesel)

	   boardman@jerry.sal.wisc.edu (Dan Boardman)

	   krweiss@chip.ucdavis.edu (Ken Weiss)

	   chuck@trantor.harris-atd.com (Chuck Musciano)

	   heycke@camis.stanford.edu (Torsten Heycke)

	   claw@spacsun.rice.edu (Colin Law)

	   jwalker@eos.ncsu.edu (Joseph C. Walker)

	   Bjorn.Borud@alkymi.unit.no (Bjorn Borud)

	   Christopher.Vance@adfa.oz.au (CJS Vance)

	   pederl@norway.hp.com (Peder Langlo)

	   I.Rutson@bradford.ac.uk (Ian Rutson)

	   Nicolas.Pioch@enst.fr (Nicolas Pioch)

	   john@charles.CS.UNLV.EDU (John Kilburg)

	   enzo@hk.net (Enzo Michelangeli)

DISTRIBUTION
  Original distribution site is
	   ftp://ftp.rz.uni-karlsruhe.de/pub/net/www/tools/giftrans.c

  To compile for MS-DOS, you need getopt:
	   ftp://ftp.rz.uni-karlsruhe.de/pub/net/www/tools/getopt.c

  MS-DOS executable can be found at
	   ftp://ftp.rz.uni-karlsruhe.de/pub/net/www/tools/giftrans.exe

at
  A template rgb.txt for use with the MS-
	   DOS version can be found
	   ftp://ftp.rz.uni-karlsruhe.de/pub/net/www/tools/rgb.txt

  Additional info can be found on
	   http://melmac.corp.harris.com/transparent_images.html

SEE ALSO
  xv(1), giftoppm(1), ppmtogif(1)