This software is copyright (C) 1991-1998, Thomas G.
Lane.
All Rights Reserved except as specified below.
Permission is hereby granted to use, copy, modify,
and distribute this
software (or portions thereof) for any purpose,
without fee, subject to these
conditions:
(1) If any part of the source code for this software is
distributed, then this
README file must be included, with this copyright
and no-warranty notice
unaltered; and any additions, deletions, or changes to
the original files
must be clearly indicated in accompanying
documentation.
(2) If only executable code is distributed, then the
accompanying
documentation must state that "this software is based
in part on the work of
the Independent JPEG Group".
(3) Permission for use of this software is granted only
if the user accepts
full responsibility for any undesirable consequences;
the authors accept
NO LIABILITY for damages of any kind.
These conditions apply to any software derived from
or based on the IJG code,
not just to the unmodified library. If you use our
work, you ought to
acknowledge us.
Permission is NOT granted for the use of any IJG
author's name or company name
in advertising or publicity relating to this software or
products derived from it.
This software may be referred to only as "the
Independent JPEG Group's
software".
We specifically permit and encourage the use of this
software as the basis of
commercial products, provided that all warranty or
liability claims are
assumed by the product vendor.
sole proprietor of its copyright holder, Aladdin
Enterprises of Menlo Park, CA.
by the usual distribution terms of the Free Software
Foundation; principally,
that you must include source code if you redistribute
it. (See the file ansi2knr.c for
full details.)
However, since ansi2knr.c is not needed as part
of any program generated from the IJG code, this
does not limit you more than
the foregoing paragraphs do.
The Unix configuration script "configure" was
produced with GNU Autoconf.
It is copyright by the Free Software Foundation but is
freely distributable.
The same holds for its supporting scripts
(config.guess, config.sub,
ltconfig, ltmain.sh). Another support script, install-sh,
is copyright
by M.I.T. but is also freely distributable.
It appears that the arithmetic coding option of the
JPEG spec is covered by
patents owned by IBM, AT&T, and Mitsubishi. Hence
arithmetic coding cannot
legally be used without obtaining one or more
licenses. For this reason,
support for arithmetic coding has been removed from
the free JPEG software.
(Since arithmetic coding provides only a marginal gain
over the unpatented
Huffman mode, it is unlikely that very many
implementations will support it.)
So far as we are aware, there are no patent
restrictions on the remaining
The IJG distribution formerly included code to read
and write GIF files.
To avoid entanglement with the Unisys LZW patent,
GIF reading support has
been removed altogether, and the GIF writer has
been simplified to produce
"uncompressed GIFs". This technique does not use
the LZW algorithm; the
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