libpng 1.2.7

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.1@3842 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 202 insertions, 171 deletions

diff --git a/png/libpng.3 b/png/libpng.3
index e7fa62e6a..0d4d82958 100644
--- a/png/libpng.3
+++ b/png/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "August 15, 2004"
+.TH LIBPNG 3 "September 12, 2004"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.2.6
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.7
 .SH SYNOPSIS
 \fI\fB
 
@@ -402,6 +402,14 @@ libpng \- Portable Network Graphics (PNG) Reference Library 1.2.6
 
 \fI\fB
 
+\fB#if \fI!defined(PNG_1_0_X)
+
+\fBvoid png_set_add_alpha (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIfiller\fP\fB, int \fIflags\fP\fB);\fP
+
+\fI\fB#endif
+
+\fI\fB
+
 \fBvoid png_set_background (png_structp \fP\fIpng_ptr\fP\fB, png_color_16p \fP\fIbackground_color\fP\fB, int \fP\fIbackground_gamma_code\fP\fB, int \fP\fIneed_expand\fP\fB, double \fIbackground_gamma\fP\fB);\fP
 
 \fI\fB
@@ -773,7 +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 1.2.6 - August 15, 2004
+ libpng version 1.2.7 - September 12, 2004
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp@users.sourceforge.net>
  Copyright (c) 1998-2004 Glenn Randers-Pehrson
@@ -810,19 +818,23 @@ Libpng was written as a companion to the PNG specification, as a way
 of reducing the amount of time and effort it takes to support the PNG
 file format in application programs.
 
-The PNG-1.2 specification is available at <http://www.libpng.org/pub/png>
-and at <ftp://ftp.uu.net/graphics/png/documents/>.
+The PNG specification (second edition), November 2003, is available as
+a W3C Recommendation and as an ISO Standard (ISO/IEC 15948:2003 (E)) at
+<http://www.w3.org/TR/2003/REC-PNG-20031110/
+The W3C and ISO documents have identical technical content.
+
+The PNG-1.2 specification is available at
+<http://www.libpng.org/pub/png/documents/>
 
 The PNG-1.0 specification is available
-as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/> and as a
+as RFC 2083 <http://www.libpng.org/pub/png/documents/> and as a
 W3C Recommendation <http://www.w3.org/TR/REC.png.html>. Some
 additional chunks are described in the special-purpose public chunks
-documents at <ftp://ftp.uu.net/graphics/png/documents/>.
+documents at <http://www.libpng.org/pub/png/documents/>.
 
 Other information
 about PNG, and the latest version of libpng, can be found at the PNG home
-page, <http://www.libpng.org/pub/png/>
-and at <ftp://ftp.uu.net/graphics/png/>.
+page, <http://www.libpng.org/pub/png/>.
 
 Most users will not have to modify the library significantly; advanced
 users may want to modify it more.  All attempts were made to make it as
@@ -855,7 +867,6 @@ same instance of a structure.  Note: thread safety may be defeated
 by use of some of the MMX assembler code in pnggccrd.c, which is only
 compiled when the user defines PNG_THREAD_UNSAFE_OK.
 
-
 .SH II. Structures
 
 There are two main structures that are important to libpng, png_struct
@@ -1073,28 +1084,28 @@ To inform libpng about your function, use
 
     png_set_read_status_fn(png_ptr, read_row_callback);
 
-%-%.SS Width and height limits
-%-%
-%-%The PNG specification allows the width and height of an image to be as
-%-%large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns.
-%-%Since very few applications really need to process such large images,
-%-%we have imposed an arbitrary 1-million limit on rows and columns.
-%-%Larger images will be rejected immediately with a png_error() call. If
-%-%you wish to override this limit, you can use
-%-%
-%-%   png_set_user_limits(png_ptr, width_max, height_max);
-%-%
-%-%to set your own limits, or use width_max = height_max = 0x7fffffffL
-%-%to allow all valid dimensions (libpng may reject some very large images
-%-%anyway because of potential buffer overflow conditions).
-%-%
-%-%You should put this statement after you create the PNG structure and
-%-%before calling png_read_info(), png_read_png(), or png_process_data().
-%-%If you need to retrieve the limits that are being applied, use
-%-%
-%-%   width_max = png_get_user_width_max(png_ptr);
-%-%   height_max = png_get_user_height_max(png_ptr);
-%-%
+.SS Width and height limits
+
+The PNG specification allows the width and height of an image to be as
+large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns.
+Since very few applications really need to process such large images,
+we have imposed an arbitrary 1-million limit on rows and columns.
+Larger images will be rejected immediately with a png_error() call. If
+you wish to override this limit, you can use
+
+   png_set_user_limits(png_ptr, width_max, height_max);
+
+to set your own limits, or use width_max = height_max = 0x7fffffffL
+to allow all valid dimensions (libpng may reject some very large images
+anyway because of potential buffer overflow conditions).
+
+You should put this statement after you create the PNG structure and
+before calling png_read_info(), png_read_png(), or png_process_data().
+If you need to retrieve the limits that are being applied, use
+
+   width_max = png_get_user_width_max(png_ptr);
+   height_max = png_get_user_height_max(png_ptr);
+
 .SS Unknown-chunk handling
 
 Now you get to set the way the library processes unknown chunks in the
@@ -1170,6 +1181,9 @@ then png_read_image(), and finally png_read_end().
 (The final parameter of this call is not yet used.  Someday it might point
 to transformation parameters required by some future input transform.)
 
+You must use png_transforms and not call any png_set_transform() functions
+when you use png_read_png().
+
 After you have called png_read_png(), you can retrieve the image data
 with
 
@@ -1534,14 +1548,14 @@ unless the library has been told to transform it into another format.
 For example, 4 bit/pixel paletted or grayscale data will be returned
 2 pixels/byte with the leftmost pixel in the high-order bits of the
 byte, unless png_set_packing() is called.  8-bit RGB data will be stored
-in RGB RGB RGB format unless png_set_filler() is called to insert filler
-bytes, either before or after each RGB triplet.  16-bit RGB data will
-be returned RRGGBB RRGGBB, with the most significant byte of the color
-value first, unless png_set_strip_16() is called to transform it to
-regular RGB RGB triplets, or png_set_filler() is called to insert
-filler bytes, either before or after each RRGGBB triplet.  Similarly,
-8-bit or 16-bit grayscale data can be modified with png_set_filler()
-or png_set_strip_16().
+in RGB RGB RGB format unless png_set_filler() or png_set_add_alpha()
+is called to insert filler bytes, either before or after each RGB triplet.
+16-bit RGB data will be returned RRGGBB RRGGBB, with the most significant
+byte of the color value first, unless png_set_strip_16() is called to
+transform it to regular RGB RGB triplets, or png_set_filler|add alpha()
+is called to insert filler bytes, either before or after each RRGGBB
+triplet.  Similarly, 8-bit or 16-bit grayscale data can be modified with
+png_set_filler(), png_set_add_alpha(), or png_set_strip_16().
 
 The following code transforms grayscale images of less than 8 to 8 bits,
 changes paletted images to RGB, and adds a full alpha channel if there is
@@ -1626,6 +1640,16 @@ does not affect images that already have full alpha channels.  To add an
 opaque alpha channel, use filler=0xff or 0xffff and PNG_FILLER_AFTER which
 will generate RGBA pixels.
 
+Note that png_set_filler() does not change the color type.  If you want
+to do that, you can add a true alpha channel with
+
+    if (color_type == PNG_COLOR_TYPE_RGB ||
+           color_type == PNG_COLOR_TYPE_GRAY)
+    png_set_add_alpha(png_ptr, filler, PNG_FILLER_AFTER);
+
+where "filler" contains the alpha value to assign to each pixel.
+This function became available in libpng-1.2.7.
+
 If you are reading an image with an alpha channel, and you need the
 data as ARGB instead of the normal PNG format RGBA:
 
@@ -2770,6 +2794,9 @@ then png_write_image(), and finally png_write_end().
 (The final parameter of this call is not yet used.  Someday it might point
 to transformation parameters required by some future output transform.)
 
+You must use png_transforms and not call any png_set_transform() functions
+when you use png_write_png().
+
 .SS The low-level write interface
 
 If you are going the low-level route instead, you are now ready to
@@ -3462,126 +3489,126 @@ When PNG_DEBUG = 1, the macros are defined, but only png_debug statements
 having level = 0 will be printed.  There aren't any such statements in
 this version of libpng, but if you insert some they will be printed.
 
-%-%.SH VI.  Runtime optimization
-%-%
-%-%A new feature in libpng 1.2.0 is the ability to dynamically switch between
-%-%standard and optimized versions of some routines.  Currently these are
-%-%limited to three computationally intensive tasks when reading PNG files:
-%-%decoding row filters, expanding interlacing, and combining interlaced or
-%-%transparent row data with previous row data.  Currently the optimized
-%-%versions are available only for x86 (Intel, AMD, etc.) platforms with
-%-%MMX support, though this may change in future versions.  (For example,
-%-%the non-MMX assembler optimizations for zlib might become similarly
-%-%runtime-selectable in future releases, in which case libpng could be
-%-%extended to support them.  Alternatively, the compile-time choice of
-%-%floating-point versus integer routines for gamma correction might become
-%-%runtime-selectable.)
-%-%
-%-%Because such optimizations tend to be very platform- and compiler-dependent,
-%-%both in how they are written and in how they perform, the new runtime code
-%-%in libpng has been written to allow programs to query, enable, and disable
-%-%either specific optimizations or all such optimizations.  For example, to
-%-%enable all possible optimizations (bearing in mind that some "optimizations"
-%-%may actually run more slowly in rare cases):
-%-%
-%-%    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-%-%       png_uint_32 mask, flags;
-%-%
-%-%       flags = png_get_asm_flags(png_ptr);
-%-%       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
-%-%       png_set_asm_flags(png_ptr, flags | mask);
-%-%    #endif
-%-%
-%-%To enable only optimizations relevant to reading PNGs, use PNG_SELECT_READ
-%-%by itself when calling png_get_asm_flagmask(); similarly for optimizing
-%-%only writing.  To disable all optimizations:
-%-%
-%-%    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-%-%       flags = png_get_asm_flags(png_ptr);
-%-%       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
-%-%       png_set_asm_flags(png_ptr, flags & ~mask);
-%-%    #endif
-%-%
-%-%To enable or disable only MMX-related features, use png_get_mmx_flagmask()
-%-%in place of png_get_asm_flagmask().  The mmx version takes one additional
-%-%parameter:
-%-%
-%-%    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-%-%       int selection = PNG_SELECT_READ | PNG_SELECT_WRITE;
-%-%       int compilerID;
-%-%
-%-%       mask = png_get_mmx_flagmask(selection, &compilerID);
-%-%    #endif
-%-%
-%-%On return, compilerID will indicate which version of the MMX assembler
-%-%optimizations was compiled.  Currently two flavors exist:  Microsoft
-%-%Visual C++ (compilerID == 1) and GNU C (a.k.a. gcc/gas, compilerID == 2).
-%-%On non-x86 platforms or on systems compiled without MMX optimizations, a
-%-%value of -1 is used.
-%-%
-%-%Note that both png_get_asm_flagmask() and png_get_mmx_flagmask() return
-%-%all valid, settable optimization bits for the version of the library that's
-%-%currently in use.  In the case of shared (dynamically linked) libraries,
-%-%this may include optimizations that did not exist at the time the code was
-%-%written and compiled.  It is also possible, of course, to enable only known,
-%-%specific optimizations; for example:
-%-%
-%-%    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-%-%       flags = PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-%-%             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
-%-%             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-%-%             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
-%-%             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-%-%             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
-%-%       png_set_asm_flags(png_ptr, flags);
-%-%    #endif
-%-%
-%-%This method would enable only the MMX read-optimizations available at the
-%-%time of libpng 1.2.0's release, regardless of whether a later version of
-%-%the DLL were actually being used.  (Also note that these functions did not
-%-%exist in versions older than 1.2.0, so any attempt to run a dynamically
-%-%linked app on such an older version would fail.)
-%-%
-%-%To determine whether the processor supports MMX instructions at all, use
-%-%the png_mmx_support() function:
-%-%
-%-%    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
-%-%       mmxsupport = png_mmx_support();
-%-%    #endif
-%-%
-%-%It returns -1 if MMX support is not compiled into libpng, 0 if MMX code
-%-%is compiled but MMX is not supported by the processor, or 1 if MMX support
-%-%is fully available.  Note that png_mmx_support(), png_get_mmx_flagmask(),
-%-%and png_get_asm_flagmask() all may be called without allocating and ini-
-%-%tializing any PNG structures (for example, as part of a usage screen or
-%-%"about" box).
-%-%
-%-%The following code can be used to prevent an application from using the
-%-%thread_unsafe features, even if libpng was built with PNG_THREAD_UNSAFE_OK
-%-%defined:
-%-%
-%-%#if defined(PNG_USE_PNGGCCRD) && defined(PNG_ASSEMBLER_CODE_SUPPORTED) \
-%-%  && defined(PNG_THREAD_UNSAFE_OK)
-%-%    /* Disable thread-unsafe features of pnggccrd */
-%-%    if (png_access_version() >= 10200)
-%-%    {
-%-%      png_uint_32 mmx_disable_mask = 0;
-%-%      png_uint_32 asm_flags;
-%-%
-%-%      mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
-%-%                          | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
-%-%                          | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
-%-%                          | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
-%-%      asm_flags = png_get_asm_flags(png_ptr);
-%-%      png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
-%-%    }
-%-%#endif
-%-%
-%-%For more extensive examples of runtime querying, enabling and disabling
-%-%of optimized features, see contrib/gregbook/readpng2.c in the libpng
-%-%source-code distribution.
-%-%
-.SH VI.  MNG support
+.SH VI.  Runtime optimization
+
+A new feature in libpng 1.2.0 is the ability to dynamically switch between
+standard and optimized versions of some routines.  Currently these are
+limited to three computationally intensive tasks when reading PNG files:
+decoding row filters, expanding interlacing, and combining interlaced or
+transparent row data with previous row data.  Currently the optimized
+versions are available only for x86 (Intel, AMD, etc.) platforms with
+MMX support, though this may change in future versions.  (For example,
+the non-MMX assembler optimizations for zlib might become similarly
+runtime-selectable in future releases, in which case libpng could be
+extended to support them.  Alternatively, the compile-time choice of
+floating-point versus integer routines for gamma correction might become
+runtime-selectable.)
+
+Because such optimizations tend to be very platform- and compiler-dependent,
+both in how they are written and in how they perform, the new runtime code
+in libpng has been written to allow programs to query, enable, and disable
+either specific optimizations or all such optimizations.  For example, to
+enable all possible optimizations (bearing in mind that some "optimizations"
+may actually run more slowly in rare cases):
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       png_uint_32 mask, flags;
+
+       flags = png_get_asm_flags(png_ptr);
+       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
+       png_set_asm_flags(png_ptr, flags | mask);
+    #endif
+
+To enable only optimizations relevant to reading PNGs, use PNG_SELECT_READ
+by itself when calling png_get_asm_flagmask(); similarly for optimizing
+only writing.  To disable all optimizations:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       flags = png_get_asm_flags(png_ptr);
+       mask = png_get_asm_flagmask(PNG_SELECT_READ | PNG_SELECT_WRITE);
+       png_set_asm_flags(png_ptr, flags & ~mask);
+    #endif
+
+To enable or disable only MMX-related features, use png_get_mmx_flagmask()
+in place of png_get_asm_flagmask().  The mmx version takes one additional
+parameter:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       int selection = PNG_SELECT_READ | PNG_SELECT_WRITE;
+       int compilerID;
+
+       mask = png_get_mmx_flagmask(selection, &compilerID);
+    #endif
+
+On return, compilerID will indicate which version of the MMX assembler
+optimizations was compiled.  Currently two flavors exist:  Microsoft
+Visual C++ (compilerID == 1) and GNU C (a.k.a. gcc/gas, compilerID == 2).
+On non-x86 platforms or on systems compiled without MMX optimizations, a
+value of -1 is used.
+
+Note that both png_get_asm_flagmask() and png_get_mmx_flagmask() return
+all valid, settable optimization bits for the version of the library that's
+currently in use.  In the case of shared (dynamically linked) libraries,
+this may include optimizations that did not exist at the time the code was
+written and compiled.  It is also possible, of course, to enable only known,
+specific optimizations; for example:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       flags = PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+             | PNG_ASM_FLAG_MMX_READ_INTERLACE    \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_UP    \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+             | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
+       png_set_asm_flags(png_ptr, flags);
+    #endif
+
+This method would enable only the MMX read-optimizations available at the
+time of libpng 1.2.0's release, regardless of whether a later version of
+the DLL were actually being used.  (Also note that these functions did not
+exist in versions older than 1.2.0, so any attempt to run a dynamically
+linked app on such an older version would fail.)
+
+To determine whether the processor supports MMX instructions at all, use
+the png_mmx_support() function:
+
+    #if defined(PNG_LIBPNG_VER) && (PNG_LIBPNG_VER >= 10200)
+       mmxsupport = png_mmx_support();
+    #endif
+
+It returns -1 if MMX support is not compiled into libpng, 0 if MMX code
+is compiled but MMX is not supported by the processor, or 1 if MMX support
+is fully available.  Note that png_mmx_support(), png_get_mmx_flagmask(),
+and png_get_asm_flagmask() all may be called without allocating and ini-
+tializing any PNG structures (for example, as part of a usage screen or
+"about" box).
+
+The following code can be used to prevent an application from using the
+thread_unsafe features, even if libpng was built with PNG_THREAD_UNSAFE_OK
+defined:
+
+#if defined(PNG_USE_PNGGCCRD) && defined(PNG_ASSEMBLER_CODE_SUPPORTED) \
+  && defined(PNG_THREAD_UNSAFE_OK)
+    /* Disable thread-unsafe features of pnggccrd */
+    if (png_access_version() >= 10200)
+    {
+      png_uint_32 mmx_disable_mask = 0;
+      png_uint_32 asm_flags;
+
+      mmx_disable_mask |= ( PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_SUB   \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_AVG   \
+                          | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH );
+      asm_flags = png_get_asm_flags(png_ptr);
+      png_set_asm_flags(png_ptr, asm_flags & ~mmx_disable_mask);
+    }
+#endif
+
+For more extensive examples of runtime querying, enabling and disabling
+of optimized features, see contrib/gregbook/readpng2.c in the libpng
+source-code distribution.
+
+.SH VII.  MNG support
 
 The MNG specification (available at http://www.libpng.org/pub/mng) allows
 certain extensions to PNG for PNG images that are embedded in MNG datastreams.
@@ -3606,7 +3633,7 @@ or any other MNG chunks; your application must provide its own support for
 them.  You may wish to consider using libmng (available at
 http://www.libmng.com) instead.
 
-.SH VII.  Changes to Libpng from version 0.88
+.SH VIII.  Changes to Libpng from version 0.88
 
 It should be noted that versions of libpng later than 0.96 are not
 distributed by the original libpng author, Guy Schalnat, nor by
@@ -3655,15 +3682,15 @@ application:
 
    png_uint_32 application_vn = PNG_LIBPNG_VER;
 
-.SH VII. Y2K Compliance in libpng
+.SH IX. Y2K Compliance in libpng
 
-August 15, 2004
+September 12, 2004
 
 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 1.2.6 are Y2K compliant.  It is my belief that earlier
+upward through 1.2.7 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
@@ -3806,6 +3833,11 @@ the first widely used release:
  1.2.6rc1-5          13    10206  12.so.0.1.2.6rc1-5
  1.0.16              10    10016  10.so.0.1.0.16
  1.2.6               13    10206  12.so.0.1.2.6
+ 1.2.7beta1-2        13    10207  12.so.0.1.2.7beta1-2
+ 1.0.17rc1           10    10017  12.so.0.1.0.17rc1
+ 1.2.7rc1            13    10207  12.so.0.1.2.7rc1
+ 1.0.17              10    10017  12.so.0.1.0.17
+ 1.2.7               13    10207  12.so.0.1.2.7
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -3822,7 +3854,7 @@ libpngpf(3), png(5)
 .LP
 .IR libpng :
 .IP
-ftp://ftp.uu.net/graphics/png
+http://libpng.sourceforge.net (follow the [DOWNLOAD] link)
 http://www.libpng.org/pub/png
 
 .LP
@@ -3832,8 +3864,6 @@ http://www.libpng.org/pub/png
 .I libpng
 or at
 .br
-ftp://ftp.uu.net/pub/archiving/zip/zlib
-.br
 ftp://ftp.info-zip.org/pub/infozip/zlib
 
 .LP
@@ -3863,13 +3893,14 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.2.6 - August 15, 2004:
+Libpng version 1.2.7 - September 12, 2004:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp@users.sourceforge.net).
 
 Supported by the PNG development group
 .br
-(png-implement@ccrc.wustl.edu).
+png-implement@ccrc.wustl.edu (subscription required; write to
+majordomo@ccrc.wustl.edu with "subscribe png-implement" in the message).
 
 .SH COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
 
@@ -3880,7 +3911,7 @@ included in the libpng distribution, the latter shall prevail.)
 If you modify libpng you may insert additional notices immediately following
 this sentence.
 
-libpng version 1.2.6, August 15, 2004, is
+libpng version 1.2.6, September 12, 2004, is
 Copyright (c) 2004 Glenn Randers-Pehrson, and is
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
@@ -3979,7 +4010,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp@users.sourceforge.net
-August 15, 2004
+September 12, 2004
 
 .\" end of man page