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 code.
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
resulting GIF files are larger than usual, but are readable by all standard GIF decoders.
We are required to state that "The Graphics Interchange Format(c) is the Copyright property of
CompuServe Incorporated. GIF(sm) is a Service Mark property of CompuServe Incorporated."
libpng
This projector product includes the open source software program "libpng" which applies the terms and
conditions provided by owner of the copyright to the "libpng".
The "libpng" are WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
List of libpng programs
libpng-1.2.7
License terms of conditions of each program which are provided by owner of the copyright to the "libpng"
are as follows.
For conditions of distribution and use, see copyright notice in png.h
Copyright (c) 1998-2004 Glenn Randers-Pehrson
(Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
(Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
This copy of the libpng notices is provided for your convenience. In case of any discrepancy between
this copy and the notices in the file png.h that is included in the libpng distribution, the latter shall prevail.
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
If you modify libpng you may insert additional notices immediately following this sentence.
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