57 lines
2.7 KiB
Plaintext
57 lines
2.7 KiB
Plaintext
|
The quantization and dithering code in pngquant is lifted from Jef Poskanzer's
|
||
|
'ppmquant', part of his wonderful PBMPLUS tool suite.
|
||
|
|
||
|
Greg Roelofs hacked it into a (in his words) "slightly cheesy" 'pamquant' back
|
||
|
in 1997 (see http://pobox.com/~newt/greg_rgba.html) and finally he ripped out
|
||
|
the cheesy file-I/O parts and replaced them with nice PNG code in December
|
||
|
2000. The PNG reading and writing code is a merged and slightly simplified
|
||
|
version of readpng, readpng2, and writepng from his book "PNG: The Definitive
|
||
|
Guide."
|
||
|
In 2014 Greg has relicensed the code under the simplified BSD license.
|
||
|
|
||
|
Note that both licenses are basically BSD-like; that is, use the code however
|
||
|
you like, as long as you acknowledge its origins.
|
||
|
|
||
|
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||
|
|
||
|
pngquant.c:
|
||
|
|
||
|
© 1989, 1991 by Jef Poskanzer.
|
||
|
|
||
|
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.
|
||
|
|
||
|
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
|
||
|
|
||
|
pngquant.c and rwpng.c/h:
|
||
|
|
||
|
© 1997-2002 by Greg Roelofs; based on an idea by Stefan Schneider.
|
||
|
© 2009-2014 by Kornel Lesiński.
|
||
|
|
||
|
All rights reserved.
|
||
|
|
||
|
Redistribution and use in source and binary forms, with or without modification,
|
||
|
are permitted provided that the following conditions are met:
|
||
|
|
||
|
1. Redistributions of source code must retain the above copyright notice,
|
||
|
this list of conditions and the following disclaimer.
|
||
|
|
||
|
2. Redistributions in binary form must reproduce the above copyright notice,
|
||
|
this list of conditions and the following disclaimer in the documentation
|
||
|
and/or other materials provided with the distribution.
|
||
|
|
||
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||
|
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
||
|
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||
|
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
||
|
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
||
|
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||
|
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||
|
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|