Copyright 1995-2020 by Alexander Lehmann <lehmann@usa.net>, Andreas Dilger <adilger@enel.ucalgary.ca>, Glenn Randers-Pehrson <randeg@alum.rpi.edu>, Greg Roelofs <newt@pobox.com>, John Bowler <jbowler@acm.org>, Tom Lane <tgl@sss.pgh.pa.us> Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation. This software is provided "as is" without express or implied warranty. [This license applies to pngcheck.c and its associated makefiles and documentation in the main directory. The files in the "gpl" subdirectory-- specifically, pngsplit.c and png-fix-IDAT-windowsize.c--are licensed under the GNU General Public License. The files in "amiga" subdirectory are Copyright 2003 Simon Goodwin and were contributed without an explicit license statement, but insofar as the "gpl" subdirectory didn't exist at the time, it's safe to assume their intended license was similar to pngcheck's, just with Simon's copyright replacing the one above.]