diff --git a/ANNOUNCE b/ANNOUNCE
index 195b64581..78a83b585 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.4.1alpha01 - November 27, 2009
+Libpng 1.4.1alpha02 - November 28, 2009
 
 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.
@@ -9,25 +9,33 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.4.1alpha01.tar.xz (LZMA-compressed, recommended)
-   1.4.1alpha01.tar.gz
-   1.4.1alpha01.tar.bz2
+   1.4.1alpha02.tar.xz (LZMA-compressed, recommended)
+   1.4.1alpha02.tar.gz
+   1.4.1alpha02.tar.bz2
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lp141a01.zip
-   lp141a01.7z
+   lp141a02.zip
+   lp141a02.7z
 
 Other information:
 
-   1.4.1alpha01-README.txt
-   1.4.1alpha01-LICENSE.txt
+   1.4.1alpha02-README.txt
+   1.4.1alpha02-LICENSE.txt
 
 Changes since the last public release (1.4.0beta107):
 
 version 1.4.1alpha01 [November 27, 2009]
-  Based on version 1.4.0beta107
+  Based on 1.4.0beta107
+
+version 1.4.1alpha02 [November 28, 2009]
+  Restored premultiplied alpha feature from version 1.4.0beta105.
+  Added "double gamma" to parameters for png_set_premultiply_alpha().
+  Added "float gamma_premultiply" member to the png_struct.
+  Moved PNG_DIVIDE_BY_255, PNG_8_BIT_PREMULTIPLY(), etc., from
+    png.h to pngpriv.h
+  Updated documentation about png_set_premultiply_alpha().
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index e1e58784e..9798141fc 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2396,8 +2396,9 @@ version 1.4.0beta104 [November 22, 2009]
   Rebuilt configure scripts with autoconf-2.65
 
 version 1.4.0beta105 [November 25, 2009]
-  Use fast integer PNG_DIVIDE_BY_255() or PNG_DIVIDE_BY_65535() to accomplish
-    alpha premultiplication when PNG_READ_COMPOSITE_NODIV_SUPPORTED is defined.
+  Use fast integer PNG_DIVIDE_BY_255() or PNG_DIVIDE_BY_65535() to
+    accomplish alpha premultiplication when
+    PNG_READ_COMPOSITE_NODIV_SUPPORTED is defined.
   Changed "/255" to "/255.0" in background calculations to make it clear
     that the 255 is used as a double.
 
@@ -2408,6 +2409,15 @@ version 1.4.0beta107 [November 27, 2009]
   Updated README
 
 version 1.4.1alpha01 [November 27, 2009]
+  Based on 1.4.0beta107
+
+version 1.4.1alpha02 [November 28, 2009]
+  Restored premultiplied alpha feature from version 1.4.0beta105.
+  Added "double gamma" to parameters for png_set_premultiply_alpha().
+  Added "float gamma_premultiply" member to the png_struct.
+  Moved PNG_DIVIDE_BY_255, PNG_8_BIT_PREMULTIPLY(), etc., from
+    png.h to pngpriv.h
+  Updated documentation about png_set_premultiply_alpha().
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/libpng-1.4.1alpha02.txt b/libpng-1.4.1alpha02.txt
index 51d931602..80e70573b 100644
--- a/libpng-1.4.1alpha02.txt
+++ b/libpng-1.4.1alpha02.txt
@@ -1,6 +1,6 @@
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.4.1alpha02 - November 27, 2009
+ libpng version 1.4.1alpha02 - November 28, 2009
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2009 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 1.4.1alpha02 - November 27, 2009
+ libpng versions 0.97, January 1998, through 1.4.1alpha02 - November 28, 2009
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
 
@@ -938,6 +938,21 @@ images) is fully transparent, with
 
     png_set_invert_alpha(png_ptr);
 
+The PNG format only supports pixels with postmultiplied alpha.
+If you want to replace the pixels, after reading them, with pixels
+that have premultiplied color samples, you can do this with
+
+    png_set_premultiply_alpha(png_ptr, output_gamma);
+
+where gamma is a double containing the gamma associated with the
+premultiplied pixels.  The gamma of the input must also be available
+when the premultiplication takes place, via a gAMA chunk in the
+input file or via png_set_gAMA().  If neither is present, the
+premultiplication will assume input_gamma==(1/2.2)
+
+If you do this, any input with a tRNS chunk will be expanded to
+have an alpha channel.
+
 PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
 they can, resulting in, for example, 8 pixels per byte for 1 bit
 files.  This code expands to 1 pixel per byte without changing the
@@ -3026,6 +3041,9 @@ after the png_malloc() to set the pointers to NULL.
 We added PNG_TRANSFORM_GRAY_TO_RGB to the available high-level
 input transforms.
 
+We added the png_set_premultiply_alpha and
+png_do_read_premultiply_alpha() functions.
+
 The call to png_do_chop() in pngrtran.c, which reduces 16-bit input
 files to 8-bit bit depth, was relocated ahead of the building
 of gamma tables.  This allows us to build 8-bit tables instead
@@ -3213,7 +3231,7 @@ Other rules can be inferred by inspecting the libpng source.
 
 XIII. Y2K Compliance in libpng
 
-November 27, 2009
+November 28, 2009
 
 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 5bee9ae5d..2a9fc4783 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "November 27, 2009"
+.TH LIBPNG 3 "November 28, 2009"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.4.1alpha01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.4.1alpha02
 .SH SYNOPSIS
 \fI\fB
 
@@ -566,6 +566,10 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.4.1alpha01
 
 \fI\fB
 
+\fBvoid png_set_premultiply_alpha (png_structp \fP\fIpng_ptr\fP\fB, double \fIgamma\fP\fB);\fP
+
+\fI\fB
+
 \fBvoid png_set_progressive_read_fn (png_structp \fP\fIpng_ptr\fP\fB, png_voidp \fP\fIprogressive_ptr\fP\fB, png_progressive_info_ptr \fP\fIinfo_fn\fP\fB, png_progressive_row_ptr \fP\fIrow_fn\fP\fB, png_progressive_end_ptr \fIend_fn\fP\fB);\fP
 
 \fI\fB
@@ -777,7 +781,7 @@ 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 1.4.1alpha01 - November 27, 2009
+ libpng version 1.4.1alpha02 - November 28, 2009
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
@@ -788,7 +792,7 @@ libpng.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.4.1alpha01 - November 27, 2009
+ libpng versions 0.97, January 1998, through 1.4.1alpha02 - November 28, 2009
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
 
@@ -1655,7 +1659,7 @@ things.
 As of libpng version 1.2.9, png_set_expand_gray_1_2_4_to_8() was
 added.  It expands the sample depth without changing tRNS to alpha.
 
-As of libpng version 1.4.1alpha01, not all possible expansions are supported.
+As of libpng version 1.4.1alpha02, not all possible expansions are supported.
 
 In the following table, the 01 means grayscale with depth<8, 31 means
 indexed with depth<8, other numerals represent the color type, "T" means
@@ -1715,6 +1719,21 @@ images) is fully transparent, with
 
     png_set_invert_alpha(png_ptr);
 
+The PNG format only supports pixels with postmultiplied alpha.
+If you want to replace the pixels, after reading them, with pixels
+that have premultiplied color samples, you can do this with
+
+    png_set_premultiply_alpha(png_ptr, output_gamma);
+
+where gamma is a double containing the gamma associated with the
+premultiplied pixels.  The gamma of the input must also be available
+when the premultiplication takes place, via a gAMA chunk in the
+input file or via png_set_gAMA().  If neither is present, the
+premultiplication will assume input_gamma==(1/2.2)
+
+If you do this, any input with a tRNS chunk will be expanded to
+have an alpha channel.
+
 PNG files pack pixels of bit depths 1, 2, and 4 into bytes as small as
 they can, resulting in, for example, 8 pixels per byte for 1 bit
 files.  This code expands to 1 pixel per byte without changing the
@@ -3803,6 +3822,9 @@ after the png_malloc() to set the pointers to NULL.
 We added PNG_TRANSFORM_GRAY_TO_RGB to the available high-level
 input transforms.
 
+We added the png_set_premultiply_alpha and
+png_do_read_premultiply_alpha() functions.
+
 The call to png_do_chop() in pngrtran.c, which reduces 16-bit input
 files to 8-bit bit depth, was relocated ahead of the building
 of gamma tables.  This allows us to build 8-bit tables instead
@@ -3990,13 +4012,13 @@ Other rules can be inferred by inspecting the libpng source.
 
 .SH XIII. Y2K Compliance in libpng
 
-November 27, 2009
+November 28, 2009
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
 
 This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.4.1alpha01 are Y2K compliant.  It is my belief that earlier
+upward through 1.4.1alpha02 are Y2K compliant.  It is my belief that earlier
 versions were also Y2K compliant.
 
 Libpng only has three year fields.  One is a 2-byte unsigned integer that
@@ -4167,7 +4189,7 @@ the first widely used release:
  1.4.0beta37-87      14    10400  14.so.14.0[.0]
  1.4.0rc01           14    10400  14.so.14.0[.0]
  1.4.0beta88-107     14    10400  14.so.14.0[.0]
- 1.4.1alpha01        14    10401  14.so.14.0[.0]
+ 1.4.1alpha01-02     14    10401  14.so.14.0[.0]
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -4223,7 +4245,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.4.1alpha01 - November 27, 2009:
+Libpng version 1.4.1alpha02 - November 28, 2009:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -4246,7 +4268,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.4.1alpha01, November 27, 2009, are
+libpng versions 1.2.6, August 15, 2004, through 1.4.1alpha02, November 28, 2009, are
 Copyright (c) 2004,2006-2007 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
@@ -4345,7 +4367,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-November 27, 2009
+November 28, 2009
 
 .\" end of man page
 
diff --git a/libpngpf.3 b/libpngpf.3
index bd7080883..62d4c28fd 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "November 27, 2009"
+.TH LIBPNGPF 3 "November 28, 2009"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.4.1alpha01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.4.1alpha02
 (private functions)
 .SH SYNOPSIS
 \fB#include <png.h>\fP
@@ -211,6 +211,10 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.4.1alpha01
 
 \fI\fB
 
+\fBvoid png_do_read_premultiply_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
 \fBvoid png_do_read_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
 \fI\fB
diff --git a/png.h b/png.h
index f85d50520..c4c5d24cd 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.4.1alpha01 - November 27, 2009
+ * libpng version 1.4.1alpha02 - November 28, 2009
  * Copyright (c) 1998-2009 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -11,7 +11,7 @@
  * 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 1.4.1alpha01 - November 27, 2009: Glenn
+ *  libpng versions 0.97, January 1998, through 1.4.1alpha02 - November 28, 2009: Glenn
  *  See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -132,7 +132,7 @@
  *    1.4.0beta37-87          14    10400  14.so.14.0[.0]
  *    1.4.0rc01               14    10400  14.so.14.0[.0]
  *    1.4.0beta88-107         14    10400  14.so.14.0[.0]
- *    1.4.1alpha01            14    10401  14.so.14.0[.0]
+ *    1.4.1alpha01-02         14    10401  14.so.14.0[.0]
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -164,7 +164,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.4.1alpha01, November 27, 2009, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.4.1alpha02, November 28, 2009, are
  * Copyright (c) 2004, 2006-2007 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:
@@ -282,7 +282,7 @@
  *    an official declaration.
  *
  *    This is your unofficial assurance that libpng from version 0.71 and
- *    upward through 1.4.1alpha01 are Y2K compliant.  It is my belief that earlier
+ *    upward through 1.4.1alpha02 are Y2K compliant.  It is my belief that earlier
  *    versions were also Y2K compliant.
  *
  *    Libpng only has three year fields.  One is a 2-byte unsigned integer
@@ -338,9 +338,9 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.4.1alpha01"
+#define PNG_LIBPNG_VER_STRING "1.4.1alpha02"
 #define PNG_HEADER_VERSION_STRING \
-   " libpng version 1.4.1alpha01 - November 27, 2009\n"
+   " libpng version 1.4.1alpha02 - November 28, 2009\n"
 
 #define PNG_LIBPNG_VER_SONUM   14
 #define PNG_LIBPNG_VER_DLLNUM  14
@@ -353,7 +353,7 @@
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
 
-#define PNG_LIBPNG_VER_BUILD  01
+#define PNG_LIBPNG_VER_BUILD  02
 
 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -1332,17 +1332,22 @@ struct png_struct_def
 /* New member added in libpng-1.2.30 */
   png_charp chunkdata PNG_DEPSTRUCT;  /* buffer for reading chunk data */
 
-/* New member added in libpng-1.4.0 */
+/* New member added in libpng-1.2.41 */
 #ifdef PNG_IO_STATE_SUPPORTED
    png_uint_32 io_state PNG_DEPSTRUCT;
 #endif
+
+/* New member added in libpng-1.4.1 */
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+   float gamma_premultiply;
+#endif
 };
 
 
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef png_structp version_1_4_1alpha01;
+typedef png_structp version_1_4_1alpha02;
 
 typedef png_struct FAR * FAR * png_structpp;
 
@@ -1524,6 +1529,11 @@ extern PNG_EXPORT(void,png_set_swap_alpha) PNGARG((png_structp png_ptr));
 extern PNG_EXPORT(void,png_set_invert_alpha) PNGARG((png_structp png_ptr));
 #endif
 
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+extern PNG_EXPORT(void,png_set_premultiply_alpha)
+  PNGARG((png_structp png_ptr, double gamma));
+#endif
+
 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
 /* Add a filler byte to 8-bit Gray or 24-bit RGB images. */
 extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
diff --git a/pngconf.h b/pngconf.h
index 9917534c4..9c29604f3 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.4.1alpha01 - November 27, 2009
+ * libpng version 1.4.1alpha02 - November 28, 2009
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2009 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -523,6 +523,9 @@
 #  ifndef PNG_NO_READ_INVERT_ALPHA
 #    define PNG_READ_INVERT_ALPHA_SUPPORTED
 #  endif
+#  ifndef PNG_NO_READ_PREMULTIPLY_ALPHA
+#      define PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+#  endif
 #  ifndef PNG_NO_READ_STRIP_ALPHA
 #    define PNG_READ_STRIP_ALPHA_SUPPORTED
 #  endif
diff --git a/pngpriv.h b/pngpriv.h
index 82c14e5a0..f5d762dc7 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -1,7 +1,7 @@
 
 /* pngpriv.h - private declarations for use inside libpng
  *
- * libpng version 1.4.1alpha01 - November 27, 2009
+ * libpng version 1.4.1alpha02 - November 28, 2009
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2009 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -127,7 +127,8 @@
                        /*     0x800000L     Unused */
 #define PNG_ADD_ALPHA         0x1000000L  /* Added to libpng-1.2.7 */
 #define PNG_EXPAND_tRNS       0x2000000L  /* Added to libpng-1.2.9 */
-                       /*   0x4000000L  unused */
+#define PNG_PREMULTIPLY_ALPHA 0x4000000L  /* Added to libpng-1.4.0 */
+                                          /* by volker */
                        /*   0x8000000L  unused */
                        /*  0x10000000L  unused */
                        /*  0x20000000L  unused */
@@ -551,6 +552,11 @@ PNG_EXTERN void png_do_strip_filler PNGARG((png_row_infop row_info,
    png_bytep row, png_uint_32 flags));
 #endif
 
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+PNG_EXTERN void png_do_read_premultiply_alpha
+   PNGARG((png_row_infop row_info, png_bytep row));
+#endif
+
 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
 PNG_EXTERN void png_do_swap PNGARG((png_row_infop row_info, png_bytep row));
 #endif
@@ -944,9 +950,24 @@ extern void *png_far_to_near PNGARG((png_structp png_ptr,png_voidp ptr,
 #define png_debug2(l, m, p1, p2)
 #endif
 
-#if 0
-extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((void));
-#endif
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+#  ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
+#    define PNG_DIVIDE_BY_255(v)  \
+       ((png_byte)(((png_uint_16)(v) + \
+       (((png_uint_16)(v) + 128) >> 8) + 128) >> 8))
+#    define PNG_DIVIDE_BY_65535(v)  \
+       ((png_byte)(((png_uint_32)(v) + \
+       (((png_uint_32)(v) + 32768L) >> 16) + 32768L) >> 16))
+#  else
+#    define PNG_DIVIDE_BY_255(v) (((png_uint_16)(v))/255)
+#    define PNG_DIVIDE_BY_65535(v) (((png_uint_32)(v))/65535L)
+#  endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
+
+#  define PNG_8_BIT_PREMULTIPLY(color,alpha) \
+      PNG_DIVIDE_BY_255((color)*(alpha))
+#  define PNG_16_BIT_PREMULTIPLY(color,alpha)\
+      PNG_DIVIDE_BY_65535((color)*(alpha))
+#endif /* PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED */
 
 /* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
 
diff --git a/pngrtran.c b/pngrtran.c
index 2289c238f..32248c018 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -1,7 +1,7 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.4.0 [November 27, 2009]
+ * Last changed in libpng 1.4.0 [November 28, 2009]
  * Copyright (c) 1998-2009 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -140,6 +140,26 @@ png_set_strip_alpha(png_structp png_ptr)
 }
 #endif
 
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+void PNGAPI
+png_set_premultiply_alpha(png_structp png_ptr, double gamma)
+{
+   png_debug(1, "in png_set_premultiply_alpha");
+
+   if(png_ptr == NULL)
+      return;
+   png_ptr->transformations |=
+     (PNG_PREMULTIPLY_ALPHA | PNG_EXPAND_tRNS);
+   png_ptr->transformations |=
+     PNG_EXPAND;  /* This shouldn't be necessary */
+   png_ptr->flags &= ~PNG_FLAG_ROW_INIT;
+   /* Check for overflow */
+   if (gamma == 0 || gamma > 21474.83)
+      png_error(png_ptr, "Invalid gamma for premultiply");
+   png_ptr->gamma_premultiply = (float)gamma;
+}
+#endif
+
 #ifdef PNG_READ_DITHER_SUPPORTED
 /* Dither file to 8 bit.  Supply a palette, the current number
  * of elements in the palette, the maximum number of elements
@@ -1492,6 +1512,12 @@ png_do_read_transformations(png_structp png_ptr)
          (png_uint_32)png_ptr->filler, png_ptr->flags);
 #endif
 
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+   if (png_ptr->transformations & PNG_PREMULTIPLY_ALPHA)
+      png_do_read_premultiply_alpha(&(png_ptr->row_info),
+         png_ptr->row_buf + 1);
+#endif
+
 #ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
    if (png_ptr->transformations & PNG_INVERT_ALPHA)
       png_do_read_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
@@ -1978,6 +2004,84 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
 }
 #endif
 
+#ifdef PNG_READ_PREMULTIPLY_ALPHA_SUPPORTED
+void /* PRIVATE */
+png_do_read_premultiply_alpha(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_read_premultiply_alpha");
+
+   {
+      png_uint_32 row_width = row_info->width;
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         /* This premultiplies the pixels with the alpha channel in RGBA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_uint_16 a = 0;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               a = *(--sp); --dp;
+               sp--; *(--dp) = PNG_8_BIT_PREMULTIPLY((*sp), a);
+               sp--; *(--dp) = PNG_8_BIT_PREMULTIPLY((*sp), a);
+               sp--; *(--dp) = PNG_8_BIT_PREMULTIPLY((*sp), a);
+            }
+         }
+         /* This premultiplies the pixels with the alpha channel in RRGGBBAA */
+         else
+         {
+            png_uint_16p sp = (png_uint_16p)(row + row_info->rowbytes);
+            png_uint_16p dp = sp;
+            png_uint_32 a = 0;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               a = *(--sp); --dp;
+               sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
+               sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
+               sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         /* This premultiplies the pixels with the alpha channel in GA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp = row + row_info->rowbytes;
+            png_bytep dp = sp;
+            png_uint_16 a = 0;
+            png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               a = *(--sp); --dp;
+               sp--; *(--dp) = PNG_8_BIT_PREMULTIPLY((*sp), a);
+            }
+         }
+         /* This premultiplies the pixels with the alpha channel in GGAA */
+         else
+         {
+            png_uint_16p sp  = (png_uint_16p) (row + row_info->rowbytes);
+            png_uint_16p dp  = sp;
+                      png_uint_32 a = 0;
+                      png_uint_32 i;
+
+            for (i = 0; i < row_width; i++)
+            {
+               a = *(--sp); --dp;
+               sp--; *(--dp) = PNG_16_BIT_PREMULTIPLY((*sp), a);
+            }
+         }
+      }
+   }
+}
+#endif
+
 #ifdef PNG_READ_FILLER_SUPPORTED
 /* Add filler channel if we have RGB color */
 void /* PRIVATE */