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libimagequant is derived from code by Jef Poskanzer and Greg Roelofs
licensed under pngquant's original license (at the end of this file),
and contains extensive changes and additions by Kornel Lesiński
licensed under GPL v3 or later.

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libimagequant © 2009-2018 by Kornel Lesiński.

                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

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- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

© 1989, 1991 by Jef Poskanzer.
© 1997, 2000, 2002 by Greg Roelofs.

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
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