[libpng12] Removed WRITE_WEIGHTED_FILTERED code, reformatted LICENSE.

8 files changed, 66 insertions, 719 deletions

diff --git a/ANNOUNCE b/ANNOUNCE
index 96acaad99..54c66ef85 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.2.54beta01 - May 15, 2015
+Libpng 1.2.54beta01 - July 13, 2015
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -43,12 +43,13 @@ Other information:
 
 Changes since the last public release (1.2.53):
 
-version 1.2.54beta01 [May 15, 2015]
+version 1.2.54beta01 [July 13, 2015]
   Fix typecast in a png_debug2() statement in png_set_text_2() to
     avoid a compiler warning in PNG_DEBUG builds.
   Fixed printf formats in pngtest.c to avoid compiler warnings and a
     Coverity warning in PNG_DEBUG builds.
   Avoid Coverity issue 80858 (REVERSE NULL) in pngtest.c PNG_DEBUG builds.
+  Removed WRITE_WEIGHTED_FILTERED code.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index ae80301b7..dd5c63c90 100644
--- a/CHANGES
+++ b/CHANGES
@@ -469,7 +469,7 @@ version 1.0.3d [September 4, 1999]
   Added new png_expand functions to scripts/pngdef.pas and pngos2.def
   Added a demo read_user_transform_fn that examines the row filters in pngtest.c
 
-version 1.0.4 [September 24, 1999]
+Version 1.0.4 [September 24, 1999, not distributed publicly]
   Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined
   Delete #define PNG_INTERNAL and include "png.h" from pngasmrd.h
   Made several minor corrections to pngtest.c
@@ -493,6 +493,7 @@ version 1.0.4c [October 1, 1999]
   Added a "png_check_version" function in png.c and pngtest.c that will generate
     a helpful compiler error if an old png.h is found in the search path.
   Changed type of png_user_transform_depth|channels from int to png_byte.
+  Added "Libpng is OSI Certified Open Source Software" statement to png.h
 version 1.0.4d [October 6, 1999]
   Changed 0.45 to 0.45455 in png_set_sRGB()
   Removed unused PLTE entries from pngnow.png
@@ -2857,12 +2858,13 @@ version 1.2.53rc02 [February 21, 2015]
 versions 1.0.63 and 1.2.53 [February 26, 2015]
   No changes.
 
-version 1.2.54beta01 [May 15, 2015]
+version 1.2.54beta01 [July 13, 2015]
   Fixed typecast in a png_debug2() statement in png_set_text_2() to
     avoid a compiler warning in PNG_DEBUG builds.
   Fixed printf formats in pngtest.c to avoid compiler warnings and a
     Coverity warning in PNG_DEBUG builds.
   Avoid Coverity issue 80858 (REVERSE NULL) in pngtest.c PNG_DEBUG builds.
+  Removed WRITE_WEIGHTED_FILTERED code.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/LICENSE b/LICENSE
index 1c7e3ca02..2ad564716 100644
--- a/LICENSE
+++ b/LICENSE
@@ -10,20 +10,14 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.2.54beta01, May 9, 2015, are
-Copyright (c) 2004, 2006-2015 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
+libpng versions 1.0.7, July 1, 2000, through 1.2.54beta01, July 13, 2015, are
+Copyright (c) 2000-2002, 2004, 2006-2015 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
+with the following individuals added to the list of Contributing Authors:
 
    Simon-Pierre Cadieux
    Eric S. Raymond
+   Cosmin Truta
    Gilles Vollant
 
 and with the following additions to the disclaimer:
@@ -36,17 +30,17 @@ and with the following additions to the disclaimer:
    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:
+Copyright (c) 1998-2000 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,
+Copyright (c) 1996-1997 Andreas Dilger, 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
@@ -57,7 +51,7 @@ with the following individuals added to the list of Contributing Authors:
    Tom Tanner
 
 libpng versions 0.5, May 1995, through 0.88, January 1996, are
-Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+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:
@@ -80,13 +74,13 @@ 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.
+  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.
+  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.
+  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
@@ -94,18 +88,18 @@ 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.
 
-
 A "png_get_copyright" function is available, for convenient use in "about"
 boxes and the like:
 
-   printf("%s",png_get_copyright(NULL));
+   printf("%s", png_get_copyright(NULL));
 
 Also, the PNG logo (in PNG format, of course) is supplied in the
 files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
 
-Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is a
-certification mark of the Open Source Initiative.
+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.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-May 9, 2015
+July 13, 2015
diff --git a/libpng-1.2.54beta01.txt b/libpng-1.2.54beta01.txt
index 3fae7c5de..10aec9423 100644
--- a/libpng-1.2.54beta01.txt
+++ b/libpng-1.2.54beta01.txt
@@ -1,6 +1,6 @@
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.2.54beta01 - May 9, 2015
+ libpng version 1.2.54beta01 - July 13, 2015
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@ libpng.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.2.54beta01 - May 9, 2015
+ libpng versions 0.97, January 1998, through 1.2.54beta01 - July 13, 2015
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
 
@@ -2757,41 +2757,6 @@ is called for the first time.)
               same as the value of filter_method used
               in png_set_IHDR().
 
-It is also possible to influence how libpng chooses from among the
-available filters.  This is done in one or both of two ways - by
-telling it how important it is to keep the same filter for successive
-rows, and by telling it the relative computational costs of the filters.
-
-    double weights[3] = {1.5, 1.3, 1.1},
-       costs[PNG_FILTER_VALUE_LAST] =
-       {1.0, 1.3, 1.3, 1.5, 1.7};
-
-    png_set_filter_heuristics(png_ptr,
-       PNG_FILTER_HEURISTIC_WEIGHTED, 3,
-       weights, costs);
-
-The weights are multiplying factors that indicate to libpng that the
-row filter should be the same for successive rows unless another row filter
-is that many times better than the previous filter.  In the above example,
-if the previous 3 filters were SUB, SUB, NONE, the SUB filter could have a
-"sum of absolute differences" 1.5 x 1.3 times higher than other filters
-and still be chosen, while the NONE filter could have a sum 1.1 times
-higher than other filters and still be chosen.  Unspecified weights are
-taken to be 1.0, and the specified weights should probably be declining
-like those above in order to emphasize recent filters over older filters.
-
-The filter costs specify for each filter type a relative decoding cost
-to be considered when selecting row filters.  This means that filters
-with higher costs are less likely to be chosen over filters with lower
-costs, unless their "sum of absolute differences" is that much smaller.
-The costs do not necessarily reflect the exact computational speeds of
-the various filters, since this would unduly influence the final image
-size.
-
-Note that the numbers above were invented purely for this example and
-are given only to help explain the function usage.  Little testing has
-been done to find optimum values for either the costs or the weights.
-
 Removing unwanted object code
 
 There are a bunch of #define's in pngconf.h that control what parts of
@@ -3183,7 +3148,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 XIII. Y2K Compliance in libpng
 
-May 9, 2015
+July 13, 2015
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
diff --git a/libpng.3 b/libpng.3
index 43bfc3707..afe92707c 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,4 +1,4 @@
-.TH LIBPNG 3 "May 9, 2015"
+.TH LIBPNG 3 "July 13, 2015"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.2.54beta01
 .SH SYNOPSIS
@@ -410,7 +410,7 @@ Following is a copy of the libpng.txt file that accompanies libpng.
 .SH LIBPNG.TXT
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.2.54beta01 - May 9, 2015
+ libpng version 1.2.54beta01 - July 13, 2015
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
@@ -421,7 +421,7 @@ libpng.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.2.54beta01 - May 9, 2015
+ libpng versions 0.97, January 1998, through 1.2.54beta01 - July 13, 2015
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2014 Glenn Randers-Pehrson
 
@@ -3167,41 +3167,6 @@ is called for the first time.)
               same as the value of filter_method used
               in png_set_IHDR().
 
-It is also possible to influence how libpng chooses from among the
-available filters.  This is done in one or both of two ways - by
-telling it how important it is to keep the same filter for successive
-rows, and by telling it the relative computational costs of the filters.
-
-    double weights[3] = {1.5, 1.3, 1.1},
-       costs[PNG_FILTER_VALUE_LAST] =
-       {1.0, 1.3, 1.3, 1.5, 1.7};
-
-    png_set_filter_heuristics(png_ptr,
-       PNG_FILTER_HEURISTIC_WEIGHTED, 3,
-       weights, costs);
-
-The weights are multiplying factors that indicate to libpng that the
-row filter should be the same for successive rows unless another row filter
-is that many times better than the previous filter.  In the above example,
-if the previous 3 filters were SUB, SUB, NONE, the SUB filter could have a
-"sum of absolute differences" 1.5 x 1.3 times higher than other filters
-and still be chosen, while the NONE filter could have a sum 1.1 times
-higher than other filters and still be chosen.  Unspecified weights are
-taken to be 1.0, and the specified weights should probably be declining
-like those above in order to emphasize recent filters over older filters.
-
-The filter costs specify for each filter type a relative decoding cost
-to be considered when selecting row filters.  This means that filters
-with higher costs are less likely to be chosen over filters with lower
-costs, unless their "sum of absolute differences" is that much smaller.
-The costs do not necessarily reflect the exact computational speeds of
-the various filters, since this would unduly influence the final image
-size.
-
-Note that the numbers above were invented purely for this example and
-are given only to help explain the function usage.  Little testing has
-been done to find optimum values for either the costs or the weights.
-
 .SS Removing unwanted object code
 
 There are a bunch of #define's in pngconf.h that control what parts of
@@ -3593,7 +3558,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 .SH XIII. Y2K Compliance in libpng
 
-May 9, 2015
+July 13, 2015
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
@@ -3990,7 +3955,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.2.54beta01 - May 9, 2015:
+Libpng version 1.2.54beta01 - July 13, 2015:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -4013,106 +3978,8 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.2.54beta01, May 9, 2015, are
-Copyright (c) 2004,2006-2015 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
+libpng versions 1.0.7, July 1, 2000, through 1.2.54beta01, July 13, 2015, are
+Copyright (c) 2000-2002, 2004, 2006-2015 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
-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:
-
-   John Bowler
-   Kevin Bracey
-   Sam Bushell
-   Magnus Holmgren
-   Greg Roelofs
-   Tom Tanner
-
-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.
-
-
-A "png_get_copyright" function is available, for convenient use in "about"
-boxes and the like:
-
-   printf("%s",png_get_copyright(NULL));
-
-Also, the PNG logo (in PNG format, of course) is supplied in the
-files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
-
-Libpng is OSI Certified Open Source Software.  OSI Certified Open Source is a
-certification mark of the Open Source Initiative.
-
-Glenn Randers-Pehrson
-glennrp at users.sourceforge.net
-May 9, 2015
-
-.\" end of man page
-
diff --git a/png.h b/png.h
index be077dc00..3988fe0bd 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.2.54beta01, May 9, 2015
+ * libpng version 1.2.54beta01, July 13, 2015
  *
  * Copyright (c) 1998-2015 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *  libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *  libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *  libpng versions 0.97, January 1998, through 1.2.54beta01, May 9, 2015: Glenn
+ *  libpng versions 0.97, January 1998, through 1.2.54beta01, July 13, 2015: Glenn
  *  See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -330,20 +330,14 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.2.54beta01, May 9, 2015, are
- * Copyright (c) 2004, 2006-2015 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
+ * libpng versions 1.0.7, July 1, 2000, through 1.2.54beta01, July 13, 2015, are
+ * Copyright (c) 2000-2002, 2004, 2006-2015 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
+ *    Cosmin Truta
  *    Gilles Vollant
  *
  * and with the following additions to the disclaimer:
@@ -356,17 +350,17 @@
  *    the user.
  *
  * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
- * Copyright (c) 1998, 1999, 2000 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:
+ * Copyright (c) 1998-2000 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,
+ * Copyright (c) 1996-1997 Andreas Dilger, 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
@@ -377,7 +371,7 @@
  *    Tom Tanner
  *
  * libpng versions 0.5, May 1995, through 0.88, January 1996, are
- * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * 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:
@@ -400,13 +394,13 @@
  * 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.
+ *   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.
+ *   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.
+ *   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
@@ -419,15 +413,16 @@
  * A "png_get_copyright" function is available, for convenient use in "about"
  * boxes and the like:
  *
- * printf("%s",png_get_copyright(NULL));
+ *    printf("%s", png_get_copyright(NULL));
  *
  * Also, the PNG logo (in PNG format, of course) is supplied in the
  * files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
  */
 
 /*
- * Libpng is OSI Certified Open Source Software.  OSI Certified is a
- * certification mark of the Open Source Initiative.
+ * 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.
  */
 
 /*
@@ -442,7 +437,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    May 9, 2015
+ *    July 13, 2015
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -506,7 +501,7 @@
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.2.54beta01"
 #define PNG_HEADER_VERSION_STRING \
-   " libpng version 1.2.54beta01 - May 9, 2015\n"
+   " libpng version 1.2.54beta01 - July 13, 2015\n"
 
 #define PNG_LIBPNG_VER_SONUM   0
 #define PNG_LIBPNG_VER_DLLNUM  13
@@ -1460,16 +1455,6 @@ struct png_struct_def
    png_uint_16p hist PNG_DEPSTRUCT;                /* histogram */
 #endif
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   png_byte heuristic_method PNG_DEPSTRUCT;        /* heuristic for row filter selection */
-   png_byte num_prev_filters PNG_DEPSTRUCT;        /* number of weights for previous rows */
-   png_bytep prev_filters PNG_DEPSTRUCT;           /* filter type(s) of previous row(s) */
-   png_uint_16p filter_weights PNG_DEPSTRUCT;      /* weight(s) for previous line(s) */
-   png_uint_16p inv_filter_weights PNG_DEPSTRUCT;  /* 1/weight(s) for previous line(s) */
-   png_uint_16p filter_costs PNG_DEPSTRUCT;        /* relative filter calculation cost */
-   png_uint_16p inv_filter_costs PNG_DEPSTRUCT;    /* 1/relative filter calculation cost */
-#endif
-
 #ifdef PNG_TIME_RFC1123_SUPPORTED
    png_charp time_buffer PNG_DEPSTRUCT;            /* String to hold RFC 1123 time text */
 #endif
@@ -1985,35 +1970,7 @@ extern PNG_EXPORT(void,png_set_filter) PNGARG((png_structp png_ptr, int method,
 #define PNG_FILTER_VALUE_PAETH 4
 #define PNG_FILTER_VALUE_LAST  5
 
-#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* EXPERIMENTAL */
-/* The "heuristic_method" is given by one of the PNG_FILTER_HEURISTIC_
- * defines, either the default (minimum-sum-of-absolute-differences), or
- * the experimental method (weighted-minimum-sum-of-absolute-differences).
- *
- * Weights are factors >= 1.0, indicating how important it is to keep the
- * filter type consistent between rows.  Larger numbers mean the current
- * filter is that many times as likely to be the same as the "num_weights"
- * previous filters.  This is cumulative for each previous row with a weight.
- * There needs to be "num_weights" values in "filter_weights", or it can be
- * NULL if the weights aren't being specified.  Weights have no influence on
- * the selection of the first row filter.  Well chosen weights can (in theory)
- * improve the compression for a given image.
- *
- * Costs are factors >= 1.0 indicating the relative decoding costs of a
- * filter type.  Higher costs indicate more decoding expense, and are
- * therefore less likely to be selected over a filter with lower computational
- * costs.  There needs to be a value in "filter_costs" for each valid filter
- * type (given by PNG_FILTER_VALUE_LAST), or it can be NULL if you aren't
- * setting the costs.  Costs try to improve the speed of decompression without
- * unduly increasing the compressed image size.
- *
- * A negative weight or cost indicates the default value is to be used, and
- * values in the range [0.0, 1.0) indicate the value is to remain unchanged.
- * The default values for both weights and costs are currently 1.0, but may
- * change if good general weighting/cost heuristics can be found.  If both
- * the weights and costs are set to 1.0, this degenerates the WEIGHTED method
- * to the UNWEIGHTED method, but with added encoding time/computation.
- */
+#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED) /* DEPRECATED */
 #ifdef PNG_FLOATING_POINT_SUPPORTED
 extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
    int heuristic_method, int num_weights, png_doublep filter_weights,
@@ -2021,9 +1978,7 @@ extern PNG_EXPORT(void,png_set_filter_heuristics) PNGARG((png_structp png_ptr,
 #endif
 #endif /*  PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
 
-/* Heuristic used for row filter selection.  These defines should NOT be
- * changed.
- */
+/* The following are no longer used and will be removed from libpng-1.7: */
 #define PNG_FILTER_HEURISTIC_DEFAULT    0  /* Currently "UNWEIGHTED" */
 #define PNG_FILTER_HEURISTIC_UNWEIGHTED 1  /* Used by libpng < 0.95 */
 #define PNG_FILTER_HEURISTIC_WEIGHTED   2  /* Experimental feature */
diff --git a/pngwrite.c b/pngwrite.c
index d8728494e..71f9748ef 100644
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -584,11 +584,6 @@ png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
    png_set_write_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL,
       png_flush_ptr_NULL);
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
-      1, png_doublep_NULL, png_doublep_NULL);
-#endif
-
 #ifdef PNG_SETJMP_SUPPORTED
    /* Applications that neglect to set up their own setjmp() and then
     * encounter a png_error() will longjmp here.  Since the jmpbuf is
@@ -731,10 +726,6 @@ png_write_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
      (png_uint_32)png_ptr->zbuf_size);
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   png_set_filter_heuristics(png_ptr, PNG_FILTER_HEURISTIC_DEFAULT,
-      1, png_doublep_NULL, png_doublep_NULL);
-#endif
 }
 
 /* Write a few rows of image data.  If the image is interlaced,
@@ -1150,14 +1141,6 @@ png_write_destroy(png_structp png_ptr)
    png_free(png_ptr, png_ptr->time_buffer);
 #endif
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   png_free(png_ptr, png_ptr->prev_filters);
-   png_free(png_ptr, png_ptr->filter_weights);
-   png_free(png_ptr, png_ptr->inv_filter_weights);
-   png_free(png_ptr, png_ptr->filter_costs);
-   png_free(png_ptr, png_ptr->inv_filter_costs);
-#endif
-
 #ifdef PNG_SETJMP_SUPPORTED
    /* Reset structure */
    png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf));
@@ -1310,117 +1293,11 @@ png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
    int num_weights, png_doublep filter_weights,
    png_doublep filter_costs)
 {
-   int i;
-
-   png_debug(1, "in png_set_filter_heuristics");
-
-   if (png_ptr == NULL)
-      return;
-   if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST)
-   {
-      png_warning(png_ptr, "Unknown filter heuristic method");
-      return;
-   }
-
-   if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT)
-   {
-      heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
-   }
-
-   if (num_weights < 0 || filter_weights == NULL ||
-      heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
-   {
-      num_weights = 0;
-   }
-
-   png_ptr->num_prev_filters = (png_byte)num_weights;
-   png_ptr->heuristic_method = (png_byte)heuristic_method;
-
-   if (num_weights > 0)
-   {
-      if (png_ptr->prev_filters == NULL)
-      {
-         png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
-            (png_uint_32)(png_sizeof(png_byte) * num_weights));
-
-         /* To make sure that the weighting starts out fairly */
-         for (i = 0; i < num_weights; i++)
-         {
-            png_ptr->prev_filters[i] = 255;
-         }
-      }
-
-      if (png_ptr->filter_weights == NULL)
-      {
-         png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
-            (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
-
-         png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
-            (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
-         for (i = 0; i < num_weights; i++)
-         {
-            png_ptr->inv_filter_weights[i] =
-            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
-         }
-      }
-
-      for (i = 0; i < num_weights; i++)
-      {
-         if (filter_weights[i] < 0.0)
-         {
-            png_ptr->inv_filter_weights[i] =
-            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
-         }
-         else
-         {
-            png_ptr->inv_filter_weights[i] =
-               (png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5);
-            png_ptr->filter_weights[i] =
-               (png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5);
-         }
-      }
-   }
-
-   /* If, in the future, there are other filter methods, this would
-    * need to be based on png_ptr->filter.
-    */
-   if (png_ptr->filter_costs == NULL)
-   {
-      png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
-         (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
-
-      png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
-         (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
-
-      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
-      {
-         png_ptr->inv_filter_costs[i] =
-         png_ptr->filter_costs[i] = PNG_COST_FACTOR;
-      }
-   }
-
-   /* Here is where we set the relative costs of the different filters.  We
-    * should take the desired compression level into account when setting
-    * the costs, so that Paeth, for instance, has a high relative cost at low
-    * compression levels, while it has a lower relative cost at higher
-    * compression settings.  The filter types are in order of increasing
-    * relative cost, so it would be possible to do this with an algorithm.
-    */
-   for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
-   {
-      if (filter_costs == NULL || filter_costs[i] < 0.0)
-      {
-         png_ptr->inv_filter_costs[i] =
-         png_ptr->filter_costs[i] = PNG_COST_FACTOR;
-      }
-      else if (filter_costs[i] >= 1.0)
-      {
-         png_ptr->inv_filter_costs[i] =
-            (png_uint_16)((double)PNG_COST_FACTOR / filter_costs[i] + 0.5);
-         png_ptr->filter_costs[i] =
-            (png_uint_16)((double)PNG_COST_FACTOR * filter_costs[i] + 0.5);
-      }
-   }
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(heuristic_method)
+   PNG_UNUSED(num_weights)
+   PNG_UNUSED(filter_weights)
+   PNG_UNUSED(filter_costs)
 }
 #endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
 
diff --git a/pngwutil.c b/pngwutil.c
index bccfaeba6..7c7c64eda 100644
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -2156,20 +2156,9 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    png_uint_32 mins, bpp;
    png_byte filter_to_do = png_ptr->do_filter;
    png_uint_32 row_bytes = row_info->rowbytes;
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   int num_p_filters = (int)png_ptr->num_prev_filters;
-#endif 
 
    png_debug(1, "in png_write_find_filter");
 
-#ifndef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-  if (png_ptr->row_number == 0 && filter_to_do == PNG_ALL_FILTERS)
-  {
-      /* These will never be selected so we need not test them. */
-      filter_to_do &= ~(PNG_FILTER_UP | PNG_FILTER_PAETH);
-  }
-#endif 
-
    /* Find out how many bytes offset each pixel is */
    bpp = (row_info->pixel_depth + 7) >> 3;
 
@@ -2219,41 +2208,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
          sum += (v < 128) ? v : 256 - v;
       }
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         png_uint_32 sumhi, sumlo;
-         int j;
-         sumlo = sum & PNG_LOMASK;
-         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK; /* Gives us some footroom */
-
-         /* Reduce the sum if we match any of the previous rows */
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
-            {
-               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         /* Factor in the cost of this filter (this is here for completeness,
-          * but it makes no sense to have a "cost" for the NONE filter, as
-          * it has the minimum possible computational cost - none).
-          */
-         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
-            PNG_COST_SHIFT;
-         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_NONE]) >>
-            PNG_COST_SHIFT;
-
-         if (sumhi > PNG_HIMASK)
-            sum = PNG_MAXSUM;
-         else
-            sum = (sumhi << PNG_HISHIFT) + sumlo;
-      }
-#endif
       mins = sum;
    }
 
@@ -2283,41 +2237,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
       png_uint_32 i;
       int v;
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      /* We temporarily increase the "minimum sum" by the factor we
-       * would reduce the sum of this filter, so that we can do the
-       * early exit comparison without scaling the sum each time.
-       */
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 lmhi, lmlo;
-         lmlo = lmins & PNG_LOMASK;
-         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
-            {
-               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
-            PNG_COST_SHIFT;
-         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
-            PNG_COST_SHIFT;
-
-         if (lmhi > PNG_HIMASK)
-            lmins = PNG_MAXSUM;
-         else
-            lmins = (lmhi << PNG_HISHIFT) + lmlo;
-      }
-#endif
-
       for (i = 0, rp = row_buf + 1, dp = png_ptr->sub_row + 1; i < bpp;
            i++, rp++, dp++)
       {
@@ -2336,37 +2255,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
             break;
       }
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 sumhi, sumlo;
-         sumlo = sum & PNG_LOMASK;
-         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_SUB)
-            {
-               sumlo = (sumlo * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               sumhi = (sumhi * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         sumlo = (sumlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
-            PNG_COST_SHIFT;
-         sumhi = (sumhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_SUB]) >>
-            PNG_COST_SHIFT;
-
-         if (sumhi > PNG_HIMASK)
-            sum = PNG_MAXSUM;
-         else
-            sum = (sumhi << PNG_HISHIFT) + sumlo;
-      }
-#endif
-
       if (sum < mins)
       {
          mins = sum;
@@ -2396,38 +2284,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
       png_uint_32 i;
       int v;
 
-
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 lmhi, lmlo;
-         lmlo = lmins & PNG_LOMASK;
-         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
-            {
-               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
-            PNG_COST_SHIFT;
-         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_UP]) >>
-            PNG_COST_SHIFT;
-
-         if (lmhi > PNG_HIMASK)
-            lmins = PNG_MAXSUM;
-         else
-            lmins = (lmhi << PNG_HISHIFT) + lmlo;
-      }
-#endif
-
       for (i = 0, rp = row_buf + 1, dp = png_ptr->up_row + 1,
            pp = prev_row + 1; i < row_bytes; i++)
       {
@@ -2439,37 +2295,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
             break;
       }
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 sumhi, sumlo;
-         sumlo = sum & PNG_LOMASK;
-         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_UP)
-            {
-               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
-            PNG_COST_SHIFT;
-         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_UP]) >>
-            PNG_COST_SHIFT;
-
-         if (sumhi > PNG_HIMASK)
-            sum = PNG_MAXSUM;
-         else
-            sum = (sumhi << PNG_HISHIFT) + sumlo;
-      }
-#endif
-
       if (sum < mins)
       {
          mins = sum;
@@ -2502,37 +2327,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
       png_uint_32 i;
       int v;
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 lmhi, lmlo;
-         lmlo = lmins & PNG_LOMASK;
-         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_AVG)
-            {
-               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
-            PNG_COST_SHIFT;
-         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_AVG]) >>
-            PNG_COST_SHIFT;
-
-         if (lmhi > PNG_HIMASK)
-            lmins = PNG_MAXSUM;
-         else
-            lmins = (lmhi << PNG_HISHIFT) + lmlo;
-      }
-#endif
-
       for (i = 0, rp = row_buf + 1, dp = png_ptr->avg_row + 1,
            pp = prev_row + 1; i < bpp; i++)
       {
@@ -2551,37 +2345,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
             break;
       }
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 sumhi, sumlo;
-         sumlo = sum & PNG_LOMASK;
-         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_NONE)
-            {
-               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
-            PNG_COST_SHIFT;
-         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_AVG]) >>
-            PNG_COST_SHIFT;
-
-         if (sumhi > PNG_HIMASK)
-            sum = PNG_MAXSUM;
-         else
-            sum = (sumhi << PNG_HISHIFT) + sumlo;
-      }
-#endif
-
       if (sum < mins)
       {
          mins = sum;
@@ -2635,37 +2398,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
       png_uint_32 i;
       int v;
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 lmhi, lmlo;
-         lmlo = lmins & PNG_LOMASK;
-         lmhi = (lmins >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
-            {
-               lmlo = (lmlo * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               lmhi = (lmhi * png_ptr->inv_filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         lmlo = (lmlo * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
-            PNG_COST_SHIFT;
-         lmhi = (lmhi * png_ptr->inv_filter_costs[PNG_FILTER_VALUE_PAETH]) >>
-            PNG_COST_SHIFT;
-
-         if (lmhi > PNG_HIMASK)
-            lmins = PNG_MAXSUM;
-         else
-            lmins = (lmhi << PNG_HISHIFT) + lmlo;
-      }
-#endif
-
       for (i = 0, rp = row_buf + 1, dp = png_ptr->paeth_row + 1,
            pp = prev_row + 1; i < bpp; i++)
       {
@@ -2716,37 +2448,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
             break;
       }
 
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-      if (png_ptr->heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
-      {
-         int j;
-         png_uint_32 sumhi, sumlo;
-         sumlo = sum & PNG_LOMASK;
-         sumhi = (sum >> PNG_HISHIFT) & PNG_HIMASK;
-
-         for (j = 0; j < num_p_filters; j++)
-         {
-            if (png_ptr->prev_filters[j] == PNG_FILTER_VALUE_PAETH)
-            {
-               sumlo = (sumlo * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-               sumhi = (sumhi * png_ptr->filter_weights[j]) >>
-                  PNG_WEIGHT_SHIFT;
-            }
-         }
-
-         sumlo = (sumlo * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
-            PNG_COST_SHIFT;
-         sumhi = (sumhi * png_ptr->filter_costs[PNG_FILTER_VALUE_PAETH]) >>
-            PNG_COST_SHIFT;
-
-         if (sumhi > PNG_HIMASK)
-            sum = PNG_MAXSUM;
-         else
-            sum = (sumhi << PNG_HISHIFT) + sumlo;
-      }
-#endif
-
       if (sum < mins)
       {
          best_row = png_ptr->paeth_row;
@@ -2756,21 +2457,6 @@ png_write_find_filter(png_structp png_ptr, png_row_infop row_info)
    /* Do the actual writing of the filtered row data from the chosen filter. */
 
    png_write_filtered_row(png_ptr, best_row);
-
-#ifdef PNG_WRITE_FILTER_SUPPORTED
-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-   /* Save the type of filter we picked this time for future calculations */
-   if (png_ptr->num_prev_filters > 0)
-   {
-      int j;
-      for (j = 1; j < num_p_filters; j++)
-      {
-         png_ptr->prev_filters[j] = png_ptr->prev_filters[j - 1];
-      }
-      png_ptr->prev_filters[j] = best_row[0];
-   }
-#endif
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
 }