Polycom IP 320 Administrator's Manual page 401

3. This Copyright notice may not be removed or altered from any source or
altered source distribution.
The Contributing Authors specifically permit, without fee, and encourage the
use of this source code as a component to supporting the MNG and JNG file
format in commercial products. If you use this source code in a product,
acknowledgment would be highly appreciated.
libPng
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
If you modify libpng you may insert additional notices immediately following
this sentence.
This code is released under the libpng license.
libpng versions 1.2.6, August 15, 2004, through 1.2.40, September 10, 2009, are
Copyright (c) 2004, 2006-2009 Glenn Randers-Pehrson, and are distributed
according to the same disclaimer and license as libpng-1.2.5 with the following
individual added to the list of Contributing Authors
Cosmin Truta
libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are
Copyright (c) 2000-2002 Glenn Randers-Pehrson, and are distributed
according to the same disclaimer and license as libpng-1.0.6 with the following
individuals added to the list of Contributing Authors
Simon-Pierre Cadieux
Eric S. Raymond
Gilles Vollant
and with the following additions to the disclaimer:
There is no warranty against interference with your enjoyment of the library
or against infringement. There is no warranty that our efforts or the library
will fulfill any of your particular purposes or needs. This library is provided
with all faults, and the entire risk of satisfactory quality, performance,
accuracy, and effort is with the user.
libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
Copyright (c) 1998, 1999 Glenn Randers-Pehrson, and are distributed
according to the same disclaimer and license as libpng-0.96, with the following
individuals added to the list of Contributing Authors:
Tom Lane
Glenn Randers-Pehrson
Willem van Schaik
libpng versions 0.89, June 1996, through 0.96, May 1997, are Copyright (c) 1996,
1997 Andreas Dilger Distributed according to the same disclaimer and license
as libpng-0.88, with the following individuals added to the list of Contributing
Authors:
Third Party Software
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