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# Qt Documentation

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  * libpng

# libpng

[Project Homepage](http://libpng.org/)

    
    
    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.
    
    Using custom versions of pnglibconf.h and pngprefix.h for Chrome.
    
    This code is released under the libpng license.
    
    libpng versions 1.0.7, July 1, 2000 through 1.6.34, September 29, 2017 are
    Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
    derived from libpng-1.0.6, 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
       Mans Rullgard
       Cosmin Truta
       Gilles Vollant
       James Yu
       Mandar Sahastrabuddhe
       Google Inc.
       Vadim Barkov
    
    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.
    
    Some files in the "contrib" directory and some configure-generated
    files that are distributed with libpng have other copyright owners and
    are released under other open source licenses.
    
    libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
    Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
    libpng-0.96, 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, are derived from libpng-0.88,
    and are distributed according to the same disclaimer and license as
    libpng-0.88, with the following individuals added to the list of
    Contributing Authors:
    
       John Bowler
       Kevin Bracey
       Sam Bushell
       Magnus Holmgren
       Greg Roelofs
       Tom Tanner
    
    Some files in the "scripts" directory have other copyright owners
    but are released under this license.
    
    libpng versions 0.5, May 1995, through 0.88, January 1996, are
    Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
    
    For the purposes of this copyright and license, "Contributing Authors"
    is defined as the following set of individuals:
    
       Andreas Dilger
       Dave Martindale
       Guy Eric Schalnat
       Paul Schmidt
       Tim Wegner
    
    The PNG Reference Library is supplied "AS IS".  The Contributing Authors
    and Group 42, Inc. disclaim all warranties, expressed or implied,
    including, without limitation, the warranties of merchantability and of
    fitness for any purpose.  The Contributing Authors and Group 42, Inc.
    assume no liability for direct, indirect, incidental, special, exemplary,
    or consequential damages, which may result from the use of the PNG
    Reference Library, even if advised of the possibility of such damage.
    
    Permission is hereby granted to use, copy, modify, and distribute this
    source code, or portions hereof, for any purpose, without fee, subject
    to the following restrictions:
    
      1. The origin of this source code must not be misrepresented.
    
      2. Altered versions must be plainly marked as such and must not
         be misrepresented as being the original source.
    
      3. This Copyright notice may not be removed or altered from any
         source or altered source distribution.
    
    The Contributing Authors and Group 42, Inc. specifically permit, without
    fee, and encourage the use of this source code as a component to
    supporting the PNG file format in commercial products.  If you use this
    source code in a product, acknowledgment is not required but would be
    appreciated.
    
    END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
    
    TRADEMARK:
    
    The name "libpng" has not been registered by the Copyright owner
    as a trademark in any jurisdiction.  However, because libpng has
    been distributed and maintained world-wide, continually since 1995,
    the Copyright owner claims "common-law trademark protection" in any
    jurisdiction where common-law trademark is recognized.
    
    OSI CERTIFICATION:
    
    Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is
    a certification mark of the Open Source Initiative. OSI has not addressed
    the additional disclaimers inserted at version 1.0.7.
    
    EXPORT CONTROL:
    
    The Copyright owner believes that the Export Control Classification
    Number (ECCN) for libpng is EAR99, which means not subject to export
    controls or International Traffic in Arms Regulations (ITAR) because
    it is open source, publicly available software, that does not contain
    any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
    734.7(b).
    
    Glenn Randers-Pehrson
    glennrp at users.sourceforge.net
    September 29, 2017

© 2020 The Qt Company Ltd. Documentation contributions included herein are the
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licensed under the terms of the [GNU Free Documentation License version
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Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in
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