diff --git a/GRRLIB/lib/png/LICENSE b/GRRLIB/lib/png/LICENSE
index 82dbe11..b7ad4b9 100644
--- a/GRRLIB/lib/png/LICENSE
+++ b/GRRLIB/lib/png/LICENSE
@@ -10,8 +10,8 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000, through 1.6.20, December 3, 2015, are
-Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
+libpng versions 1.0.7, July 1, 2000 through 1.6.23, June 9, 2016 are
+Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, 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:
@@ -32,6 +32,10 @@ and with the following additions to the disclaimer:
    risk of satisfactory quality, performance, accuracy, and effort is with
    the user.
 
+Some files in the "contrib" directory and some configure-generated
+files that are distributed with libpng have other copyright owners and
+are released under other open source licenses.
+
 libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
 Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
 libpng-0.96, and are distributed according to the same disclaimer and
@@ -55,6 +59,9 @@ Contributing Authors:
    Greg Roelofs
    Tom Tanner
 
+Some files in the "scripts" directory have other copyright owners
+but are released under this license.
+
 libpng versions 0.5, May 1995, through 0.88, January 1996, are
 Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
 
@@ -95,18 +102,29 @@ appreciated.
 
 END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
 
-A "png_get_copyright" function is available, for convenient use in "about"
-boxes and the like:
+TRADEMARK:
 
-   printf("%s", png_get_copyright(NULL));
+The name "libpng" has not been registered by the Copyright owner
+as a trademark in any jurisdiction.  However, because libpng has
+been distributed and maintained world-wide, continually since 1995,
+the Copyright owner claims "common-law trademark protection" in any
+jurisdiction where common-law trademark is recognized.
 
-Also, the PNG logo (in PNG format, of course) is supplied in the
-files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
+OSI CERTIFICATION:
 
 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.
 
+EXPORT CONTROL:
+
+The Copyright owner believes that the Export Control Classification
+Number (ECCN) for libpng is EAR99, which means not subject to export
+controls or International Traffic in Arms Regulations (ITAR) because
+it is open source, publicly available software, that does not contain
+any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
+734.7(b).
+
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-December 3, 2015
+June 9, 2016
diff --git a/GRRLIB/lib/png/png.c b/GRRLIB/lib/png/png.c
index c183e3f..1720ca0 100644
--- a/GRRLIB/lib/png/png.c
+++ b/GRRLIB/lib/png/png.c
@@ -2,7 +2,7 @@
 /* png.c - location for general purpose libpng functions
  *
  * Last changed in libpng 1.6.19 [November 12, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
@@ -14,7 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_20 Your_png_h_is_not_version_1_6_20;
+typedef png_libpng_version_1_6_23 Your_png_h_is_not_version_1_6_23;
 
 /* Tells libpng that we have already handled the first "num_bytes" bytes
  * of the PNG file signature.  If the PNG data is embedded into another
@@ -775,14 +775,15 @@ png_get_copyright(png_const_structrp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.20 - December 3, 2015" PNG_STRING_NEWLINE \
-      "Copyright (c) 1998-2015 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
+      "libpng version 1.6.23 - June 9, 2016" PNG_STRING_NEWLINE \
+      "Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson" \
+      PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
       "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
       PNG_STRING_NEWLINE;
 #  else
-   return "libpng version 1.6.20 - December 3, 2015\
-      Copyright (c) 1998-2015 Glenn Randers-Pehrson\
+   return "libpng version 1.6.23 - June 9, 2016\
+      Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
 #  endif
diff --git a/GRRLIB/lib/png/png.h b/GRRLIB/lib/png/png.h
index 4d03dfc..1efb0b0 100644
--- a/GRRLIB/lib/png/png.h
+++ b/GRRLIB/lib/png/png.h
@@ -1,9 +1,9 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.20, December 3, 2015
+ * libpng version 1.6.23, June 9, 2016
  *
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.6.20, December 3, 2015:
+ *   libpng versions 0.97, January 1998, through 1.6.23, June 9, 2016:
  *     Glenn Randers-Pehrson.
  *   See also "Contributing Authors", below.
  */
@@ -25,8 +25,12 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.0.7, July 1, 2000, through 1.6.20, December 3, 2015, are
- * Copyright (c) 2000-2002, 2004, 2006-2015 Glenn Randers-Pehrson, are
+ * Some files in the "contrib" directory and some configure-generated
+ * files that are distributed with libpng have other copyright owners and
+ * are released under other open source licenses.
+ *
+ * libpng versions 1.0.7, July 1, 2000 through 1.6.23, June 9, 2016 are
+ * Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
  * derived from libpng-1.0.6, 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:
@@ -47,6 +51,10 @@
  *    risk of satisfactory quality, performance, accuracy, and effort is with
  *    the user.
  *
+ * Some files in the "contrib" directory have other copyright owners and
+ * are released under other open source licenses.
+ *
+ *
  * libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
  * Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
  * libpng-0.96, and are distributed according to the same disclaimer and
@@ -57,6 +65,9 @@
  *    Glenn Randers-Pehrson
  *    Willem van Schaik
  *
+ * Some files in the "scripts" directory have different copyright owners
+ * but are also released under this license.
+ *
  * libpng versions 0.89, June 1996, through 0.96, May 1997, are
  * Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
  * and are distributed according to the same disclaimer and license as
@@ -70,6 +81,9 @@
  *    Greg Roelofs
  *    Tom Tanner
  *
+ * Some files in the "scripts" directory have other copyright owners
+ * but are released under this license.
+ *
  * libpng versions 0.5, May 1995, through 0.88, January 1996, are
  * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
  *
@@ -109,6 +123,29 @@
  * appreciated.
  *
  * END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
+ *
+ * TRADEMARK:
+ *
+ * The name "libpng" has not been registered by the Copyright owner
+ * as a trademark in any jurisdiction.  However, because libpng has
+ * been distributed and maintained world-wide, continually since 1995,
+ * the Copyright owner claims "common-law trademark protection" in any
+ * jurisdiction where common-law trademark is recognized.
+ *
+ * OSI CERTIFICATION:
+ *
+ * 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.
+ *
+ * EXPORT CONTROL:
+ *
+ * The Copyright owner believes that the Export Control Classification
+ * Number (ECCN) for libpng is EAR99, which means not subject to export
+ * controls or International Traffic in Arms Regulations (ITAR) because
+ * it is open source, publicly available software, that does not contain
+ * any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
+ * 734.7(b).
  */
 
 /*
@@ -121,12 +158,6 @@
  * 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. OSI has not addressed
- * the additional disclaimers inserted at version 1.0.7.
- */
-
 /*
  * The contributing authors would like to thank all those who helped
  * with testing, bug fixes, and patience.  This wouldn't have been
@@ -182,11 +213,11 @@
  *    ...
  *    1.0.19                  10    10019  10.so.0.19[.0]
  *    ...
- *    1.2.53                  13    10253  12.so.0.53[.0]
+ *    1.2.56                  13    10256  12.so.0.56[.0]
  *    ...
- *    1.5.23                  15    10523  15.so.15.23[.0]
+ *    1.5.27                  15    10527  15.so.15.27[.0]
  *    ...
- *    1.6.20                  16    10620  16.so.16.20[.0]
+ *    1.6.23                  16    10623  16.so.16.23[.0]
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -214,13 +245,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    December 3, 2015
+ *    June 9, 2016
  *
  *    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 1.6.20 are Y2K compliant.  It is my belief that
+ *    upward through 1.6.23 are Y2K compliant.  It is my belief that
  *    earlier versions were also Y2K compliant.
  *
  *    Libpng only has two year fields.  One is a 2-byte unsigned integer
@@ -282,9 +313,9 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.20"
+#define PNG_LIBPNG_VER_STRING "1.6.23"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.6.20 - December 3, 2015\n"
+     " libpng version 1.6.23 - June 9, 2016\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
@@ -292,7 +323,7 @@
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
 #define PNG_LIBPNG_VER_MINOR   6
-#define PNG_LIBPNG_VER_RELEASE 20
+#define PNG_LIBPNG_VER_RELEASE 23
 
 /* This should match the numeric part of the final component of
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
@@ -323,7 +354,7 @@
  * version 1.0.0 was mis-numbered 100 instead of 10000).  From
  * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
  */
-#define PNG_LIBPNG_VER 10620 /* 1.6.20 */
+#define PNG_LIBPNG_VER 10623 /* 1.6.23 */
 
 /* Library configuration: these options cannot be changed after
  * the library has been built.
@@ -433,7 +464,7 @@ extern "C" {
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef char* png_libpng_version_1_6_20;
+typedef char* png_libpng_version_1_6_23;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -734,24 +765,22 @@ typedef png_unknown_chunk * * png_unknown_chunkpp;
  * data in the info_struct to be written into the output file.  The values
  * of the PNG_INFO_<chunk> defines should NOT be changed.
  */
-#define PNG_INFO_gAMA 0x0001
-#define PNG_INFO_sBIT 0x0002
-#define PNG_INFO_cHRM 0x0004
-#define PNG_INFO_PLTE 0x0008
-#define PNG_INFO_tRNS 0x0010
-#define PNG_INFO_bKGD 0x0020
-#define PNG_INFO_hIST 0x0040
-#define PNG_INFO_pHYs 0x0080
-#define PNG_INFO_oFFs 0x0100
-#define PNG_INFO_tIME 0x0200
-#define PNG_INFO_pCAL 0x0400
-#define PNG_INFO_sRGB 0x0800   /* GR-P, 0.96a */
-#define PNG_INFO_iCCP 0x1000   /* ESR, 1.0.6 */
-#define PNG_INFO_sPLT 0x2000   /* ESR, 1.0.6 */
-#define PNG_INFO_sCAL 0x4000   /* ESR, 1.0.6 */
-#if INT_MAX >= 0x8000 /* else this might break */
-#define PNG_INFO_IDAT 0x8000   /* ESR, 1.0.6 */
-#endif
+#define PNG_INFO_gAMA 0x0001U
+#define PNG_INFO_sBIT 0x0002U
+#define PNG_INFO_cHRM 0x0004U
+#define PNG_INFO_PLTE 0x0008U
+#define PNG_INFO_tRNS 0x0010U
+#define PNG_INFO_bKGD 0x0020U
+#define PNG_INFO_hIST 0x0040U
+#define PNG_INFO_pHYs 0x0080U
+#define PNG_INFO_oFFs 0x0100U
+#define PNG_INFO_tIME 0x0200U
+#define PNG_INFO_pCAL 0x0400U
+#define PNG_INFO_sRGB 0x0800U  /* GR-P, 0.96a */
+#define PNG_INFO_iCCP 0x1000U  /* ESR, 1.0.6 */
+#define PNG_INFO_sPLT 0x2000U  /* ESR, 1.0.6 */
+#define PNG_INFO_sCAL 0x4000U  /* ESR, 1.0.6 */
+#define PNG_INFO_IDAT 0x8000U  /* ESR, 1.0.6 */
 
 /* This is used for the transformation routines, as some of them
  * change these values for the row.  It also should enable using
@@ -1322,7 +1351,7 @@ PNG_EXPORT(229, void, png_set_scale_16, (png_structrp png_ptr));
 #endif
 
 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-#define PNG_READ_16_TO_8 SUPPORTED /* Name prior to 1.5.4 */
+#define PNG_READ_16_TO_8_SUPPORTED /* Name prior to 1.5.4 */
 /* Strip the second byte of information from a 16-bit depth file. */
 PNG_EXPORT(48, void, png_set_strip_16, (png_structrp png_ptr));
 #endif
@@ -1473,8 +1502,8 @@ PNG_EXPORT(67, void, png_set_filter, (png_structrp png_ptr, int method,
 #define PNG_FILTER_UP      0x20
 #define PNG_FILTER_AVG     0x40
 #define PNG_FILTER_PAETH   0x80
-#define PNG_ALL_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP | \
-                         PNG_FILTER_AVG | PNG_FILTER_PAETH)
+#define PNG_FAST_FILTERS (PNG_FILTER_NONE | PNG_FILTER_SUB | PNG_FILTER_UP)
+#define PNG_ALL_FILTERS (PNG_FAST_FILTERS | PNG_FILTER_AVG | PNG_FILTER_PAETH)
 
 /* Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
  * These defines should NOT be changed.
@@ -1751,21 +1780,21 @@ PNG_EXPORT(99, void, png_data_freer, (png_const_structrp png_ptr,
 #define PNG_SET_WILL_FREE_DATA 1
 #define PNG_USER_WILL_FREE_DATA 2
 /* Flags for png_ptr->free_me and info_ptr->free_me */
-#define PNG_FREE_HIST 0x0008
-#define PNG_FREE_ICCP 0x0010
-#define PNG_FREE_SPLT 0x0020
-#define PNG_FREE_ROWS 0x0040
-#define PNG_FREE_PCAL 0x0080
-#define PNG_FREE_SCAL 0x0100
+#define PNG_FREE_HIST 0x0008U
+#define PNG_FREE_ICCP 0x0010U
+#define PNG_FREE_SPLT 0x0020U
+#define PNG_FREE_ROWS 0x0040U
+#define PNG_FREE_PCAL 0x0080U
+#define PNG_FREE_SCAL 0x0100U
 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
-#  define PNG_FREE_UNKN 0x0200
+#  define PNG_FREE_UNKN 0x0200U
 #endif
-/*      PNG_FREE_LIST 0x0400    removed in 1.6.0 because it is ignored */
-#define PNG_FREE_PLTE 0x1000
-#define PNG_FREE_TRNS 0x2000
-#define PNG_FREE_TEXT 0x4000
-#define PNG_FREE_ALL  0x7fff
-#define PNG_FREE_MUL  0x4220 /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
+/*      PNG_FREE_LIST 0x0400U   removed in 1.6.0 because it is ignored */
+#define PNG_FREE_PLTE 0x1000U
+#define PNG_FREE_TRNS 0x2000U
+#define PNG_FREE_TEXT 0x4000U
+#define PNG_FREE_ALL  0x7fffU
+#define PNG_FREE_MUL  0x4220U /* PNG_FREE_SPLT|PNG_FREE_TEXT|PNG_FREE_UNKN */
 
 #ifdef PNG_USER_MEM_SUPPORTED
 PNG_EXPORTA(100, png_voidp, png_malloc_default, (png_const_structrp png_ptr,
@@ -2889,12 +2918,19 @@ typedef struct
     * is the minimum 'row stride', the minimum count of components between each
     * row.  For a color-mapped image this is the minimum number of bytes in a
     * row.
+    *
+    * WARNING: this macro overflows for some images with more than one component
+    * and very large image widths.  libpng will refuse to process an image where
+    * this macro would overflow.
     */
 
 #define PNG_IMAGE_BUFFER_SIZE(image, row_stride)\
    (PNG_IMAGE_PIXEL_COMPONENT_SIZE((image).format)*(image).height*(row_stride))
    /* Return the size, in bytes, of an image buffer given a png_image and a row
     * stride - the number of components to leave space for in each row.
+    *
+    * WARNING: this macro overflows a 32-bit integer for some large PNG images,
+    * libpng will refuse to process an image where such an overflow would occur.
     */
 
 #define PNG_IMAGE_SIZE(image)\
@@ -3015,7 +3051,6 @@ PNG_EXPORT(238, void, png_image_free, (png_imagep image));
 #endif /* SIMPLIFIED_READ */
 
 #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
-#ifdef PNG_STDIO_SUPPORTED
 /* WRITE APIS
  * ----------
  * For write you must initialize a png_image structure to describe the image to
@@ -3032,6 +3067,7 @@ PNG_EXPORT(238, void, png_image_free, (png_imagep image));
  *    values do not correspond to the colors in sRGB.
  * colormap_entries: set to the number of entries in the color-map (0 to 256)
  */
+#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
 PNG_EXPORT(239, int, png_image_write_to_file, (png_imagep image,
    const char *file, int convert_to_8bit, const void *buffer,
    png_int_32 row_stride, const void *colormap));
@@ -3041,8 +3077,9 @@ PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
    int convert_to_8_bit, const void *buffer, png_int_32 row_stride,
    const void *colormap));
    /* Write the image to the given (FILE*). */
+#endif /* SIMPLIFIED_WRITE_STDIO */
 
-/* With both write APIs if image is in one of the linear formats with 16-bit
+/* With all write APIs if image is in one of the linear formats with 16-bit
  * data then setting convert_to_8_bit will cause the output to be an 8-bit PNG
  * gamma encoded according to the sRGB specification, otherwise a 16-bit linear
  * encoded PNG file is written.
@@ -3054,13 +3091,103 @@ PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
  *
  * With all APIs row_stride is handled as in the read APIs - it is the spacing
  * from one row to the next in component sized units (1 or 2 bytes) and if
- * negative indicates a bottom-up row layout in the buffer.  If row_stride is zero,
- * libpng will calculate it for you from the image width and number of channels.
+ * negative indicates a bottom-up row layout in the buffer.  If row_stride is
+ * zero, libpng will calculate it for you from the image width and number of
+ * channels.
  *
- * Note that the write API does not support interlacing, sub-8-bit pixels, indexed
- * PNG (color_type 3) or most ancillary chunks.
+ * Note that the write API does not support interlacing, sub-8-bit pixels or
+ * most ancillary chunks.  If you need to write text chunks (e.g. for copyright
+ * notices) you need to use one of the other APIs.
  */
-#endif /* STDIO */
+
+PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory,
+   png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8_bit,
+   const void *buffer, png_int_32 row_stride, const void *colormap));
+   /* Write the image to the given memory buffer.  The function both writes the
+    * whole PNG data stream to *memory and updates *memory_bytes with the count
+    * of bytes written.
+    *
+    * 'memory' may be NULL.  In this case *memory_bytes is not read however on
+    * success the number of bytes which would have been written will still be
+    * stored in *memory_bytes.  On failure *memory_bytes will contain 0.
+    *
+    * If 'memory' is not NULL it must point to memory[*memory_bytes] of
+    * writeable memory.
+    *
+    * If the function returns success memory[*memory_bytes] (if 'memory' is not
+    * NULL) contains the written PNG data.  *memory_bytes will always be less
+    * than or equal to the original value.
+    *
+    * If the function returns false and *memory_bytes was not changed an error
+    * occured during write.  If *memory_bytes was changed, or is not 0 if
+    * 'memory' was NULL, the write would have succeeded but for the memory
+    * buffer being too small.  *memory_bytes contains the required number of
+    * bytes and will be bigger that the original value.
+    */
+
+#define png_image_write_get_memory_size(image, size, convert_to_8_bit, buffer,\
+   row_stride, colormap)\
+   png_image_write_to_memory(&(image), 0, &(size), convert_to_8_bit, buffer,\
+         row_stride, colormap)
+   /* Return the amount of memory in 'size' required to compress this image.
+    * The png_image structure 'image' must be filled in as in the above
+    * function and must not be changed before the actual write call, the buffer
+    * and all other parameters must also be identical to that in the final
+    * write call.  The 'size' variable need not be initialized.
+    *
+    * NOTE: the macro returns true/false, if false is returned 'size' will be
+    * set to zero and the write failed and probably will fail if tried again.
+    */
+
+/* You can pre-allocate the buffer by making sure it is of sufficient size
+ * regardless of the amount of compression achieved.  The buffer size will
+ * always be bigger than the original image and it will never be filled.  The
+ * following macros are provided to assist in allocating the buffer.
+ */
+#define PNG_IMAGE_DATA_SIZE(image) (PNG_IMAGE_SIZE(image)+(image).height)
+   /* The number of uncompressed bytes in the PNG byte encoding of the image;
+    * uncompressing the PNG IDAT data will give this number of bytes.
+    *
+    * NOTE: while PNG_IMAGE_SIZE cannot overflow for an image in memory this
+    * macro can because of the extra bytes used in the PNG byte encoding.  You
+    * need to avoid this macro if your image size approaches 2^30 in width or
+    * height.  The same goes for the remainder of these macros; they all produce
+    * bigger numbers than the actual in-memory image size.
+    */
+#ifndef PNG_ZLIB_MAX_SIZE
+#  define PNG_ZLIB_MAX_SIZE(b) ((b)+(((b)+7U)>>3)+(((b)+63U)>>6)+11U)
+   /* An upper bound on the number of compressed bytes given 'b' uncompressed
+    * bytes.  This is based on deflateBounds() in zlib; different
+    * implementations of zlib compression may conceivably produce more data so
+    * if your zlib implementation is not zlib itself redefine this macro
+    * appropriately.
+    */
+#endif
+
+#define PNG_IMAGE_COMPRESSED_SIZE_MAX(image)\
+   PNG_ZLIB_MAX_SIZE((png_alloc_size_t)PNG_IMAGE_DATA_SIZE(image))
+   /* An upper bound on the size of the data in the PNG IDAT chunks. */
+
+#define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\
+   ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\
+    (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\
+     12U+3U*(image).colormap_entries/*PLTE data*/+\
+     (((image).format&PNG_FORMAT_FLAG_ALPHA)?\
+      12U/*tRNS*/+(image).colormap_entries:0U):0U)+\
+    12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size))
+   /* A helper for the following macro; if your compiler cannot handle the
+    * following macro use this one with the result of
+    * PNG_IMAGE_COMPRESSED_SIZE_MAX(image) as the second argument (most
+    * compilers should handle this just fine.)
+    */
+
+#define PNG_IMAGE_PNG_SIZE_MAX(image)\
+   PNG_IMAGE_PNG_SIZE_MAX_(image, PNG_IMAGE_COMPRESSED_SIZE_MAX(image))
+   /* An upper bound on the total length of the PNG data stream for 'image'.
+    * The result is of type png_alloc_size_t, on 32-bit systems this may
+    * overflow even though PNG_IMAGE_DATA_SIZE does not overflow; the write will
+    * run out of buffer space but return a corrected size which should work.
+    */
 #endif /* SIMPLIFIED_WRITE */
 /*******************************************************************************
  *  END OF SIMPLIFIED API
@@ -3118,7 +3245,7 @@ PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
  * one to use is one more than this.)
  */
 #ifdef PNG_EXPORT_LAST_ORDINAL
-  PNG_EXPORT_LAST_ORDINAL(244);
+  PNG_EXPORT_LAST_ORDINAL(245);
 #endif
 
 #ifdef __cplusplus
diff --git a/GRRLIB/lib/png/pngconf.h b/GRRLIB/lib/png/pngconf.h
index 92f2500..b0ccc8c 100644
--- a/GRRLIB/lib/png/pngconf.h
+++ b/GRRLIB/lib/png/pngconf.h
@@ -1,9 +1,9 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.6.20, December 3, 2015
+ * libpng version 1.6.23, June 9, 2016
  *
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
diff --git a/GRRLIB/lib/png/pngdebug.h b/GRRLIB/lib/png/pngdebug.h
index 6a01b10..15a7ed0 100644
--- a/GRRLIB/lib/png/pngdebug.h
+++ b/GRRLIB/lib/png/pngdebug.h
@@ -2,7 +2,7 @@
 /* pngdebug.h - Debugging macros for libpng, also used in pngtest.c
  *
  * Last changed in libpng 1.6.8 [December 19, 2013]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2013 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.)
  *
diff --git a/GRRLIB/lib/png/pngerror.c b/GRRLIB/lib/png/pngerror.c
index bdb959e..3fc8092 100644
--- a/GRRLIB/lib/png/pngerror.c
+++ b/GRRLIB/lib/png/pngerror.c
@@ -2,7 +2,7 @@
 /* pngerror.c - stub functions for i/o and memory allocation
  *
  * Last changed in libpng 1.6.15 [November 20, 2014]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2014 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.)
  *
@@ -44,7 +44,7 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
    if (png_ptr != NULL)
    {
       if ((png_ptr->flags &
-         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0
+         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0)
       {
          if (*error_message == PNG_LITERAL_SHARP)
          {
diff --git a/GRRLIB/lib/png/pngget.c b/GRRLIB/lib/png/pngget.c
index 743a6a9..14fc7be 100644
--- a/GRRLIB/lib/png/pngget.c
+++ b/GRRLIB/lib/png/pngget.c
@@ -2,7 +2,7 @@
 /* pngget.c - retrieval of values from info struct
  *
  * Last changed in libpng 1.6.17 [March 26, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
@@ -456,11 +456,11 @@ png_get_pHYs_dpi(png_const_structrp png_ptr, png_const_inforp info_ptr,
    return (retval);
 }
 #endif /* pHYs */
-#endif  /* INCH_CONVERSIONS */
+#endif /* INCH_CONVERSIONS */
 
 /* png_get_channels really belongs in here, too, but it's been around longer */
 
-#endif  /* EASY_ACCESS */
+#endif /* EASY_ACCESS */
 
 
 png_byte PNGAPI
@@ -1142,19 +1142,19 @@ png_get_compression_buffer_size(png_const_structrp png_ptr)
       return 0;
 
 #ifdef PNG_WRITE_SUPPORTED
-      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
+   if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
 #endif
    {
 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-         return png_ptr->IDAT_read_size;
+      return png_ptr->IDAT_read_size;
 #else
-         return PNG_IDAT_READ_SIZE;
+      return PNG_IDAT_READ_SIZE;
 #endif
    }
 
 #ifdef PNG_WRITE_SUPPORTED
-      else
-         return png_ptr->zbuffer_size;
+   else
+      return png_ptr->zbuffer_size;
 #endif
 }
 
diff --git a/GRRLIB/lib/png/pnginfo.h b/GRRLIB/lib/png/pnginfo.h
index 4bd264b..361ed8b 100644
--- a/GRRLIB/lib/png/pnginfo.h
+++ b/GRRLIB/lib/png/pnginfo.h
@@ -2,7 +2,7 @@
 /* pnginfo.h - header file for PNG reference library
  *
  * Last changed in libpng 1.6.1 [March 28, 2013]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2013 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.)
  *
diff --git a/GRRLIB/lib/png/pngmem.c b/GRRLIB/lib/png/pngmem.c
index 45ac557..7bcfd00 100644
--- a/GRRLIB/lib/png/pngmem.c
+++ b/GRRLIB/lib/png/pngmem.c
@@ -2,7 +2,7 @@
 /* pngmem.c - stub functions for memory allocation
  *
  * Last changed in libpng 1.6.15 [November 20, 2014]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2014 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.)
  *
diff --git a/GRRLIB/lib/png/pngpread.c b/GRRLIB/lib/png/pngpread.c
index 89ffc40..ca300e7 100644
--- a/GRRLIB/lib/png/pngpread.c
+++ b/GRRLIB/lib/png/pngpread.c
@@ -1,8 +1,8 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.23 [June 9, 2016]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -210,12 +210,14 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
           (png_ptr->mode & PNG_HAVE_PLTE) == 0)
          png_error(png_ptr, "Missing PLTE before IDAT");
 
-      png_ptr->mode |= PNG_HAVE_IDAT;
       png_ptr->process_mode = PNG_READ_IDAT_MODE;
 
-      if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
-         if (png_ptr->push_length == 0)
-            return;
+      if ((png_ptr->mode & PNG_HAVE_IDAT) != 0)
+         if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
+            if (png_ptr->push_length == 0)
+               return;
+
+      png_ptr->mode |= PNG_HAVE_IDAT;
 
       if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
          png_benign_error(png_ptr, "Too many IDATs found");
@@ -499,7 +501,10 @@ png_push_save_buffer(png_structrp png_ptr)
          png_error(png_ptr, "Insufficient memory for save_buffer");
       }
 
-      memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+      if (old_buffer)
+         memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+      else if (png_ptr->save_buffer_size)
+         png_error(png_ptr, "save_buffer error");
       png_free(png_ptr, old_buffer);
       png_ptr->save_buffer_max = new_max;
    }
diff --git a/GRRLIB/lib/png/pngpriv.h b/GRRLIB/lib/png/pngpriv.h
index e53fb0e..9338df3 100644
--- a/GRRLIB/lib/png/pngpriv.h
+++ b/GRRLIB/lib/png/pngpriv.h
@@ -1,8 +1,8 @@
 
 /* pngpriv.h - private declarations for use inside libpng
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -1917,6 +1917,9 @@ PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #endif
 
+PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
+   png_const_charp key, png_bytep new_key), PNG_EMPTY);
+
 /* Maintainer: Put new private prototypes here ^ */
 
 #include "pngdebug.h"
diff --git a/GRRLIB/lib/png/pngread.c b/GRRLIB/lib/png/pngread.c
index 9cb4d2e..0ff6238 100644
--- a/GRRLIB/lib/png/pngread.c
+++ b/GRRLIB/lib/png/pngread.c
@@ -1,8 +1,8 @@
 
 /* pngread.c - read a PNG file
  *
- * Last changed in libpng 1.6.17 [March 26, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.23 [June 9, 2016]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -127,7 +127,10 @@ png_read_info(png_structrp png_ptr, png_inforp info_ptr)
       }
 
       else if ((png_ptr->mode & PNG_HAVE_IDAT) != 0)
+      {
+         png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
          png_ptr->mode |= PNG_AFTER_IDAT;
+      }
 
       /* This should be a binary subdivision search or a hash for
        * matching the chunk name rather than a linear search.
@@ -785,6 +788,9 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
       png_uint_32 length = png_read_chunk_header(png_ptr);
       png_uint_32 chunk_name = png_ptr->chunk_name;
 
+      if (chunk_name != png_IDAT)
+         png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
+
       if (chunk_name == png_IEND)
          png_handle_IEND(png_ptr, info_ptr, length);
 
@@ -799,9 +805,9 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
       {
          if (chunk_name == png_IDAT)
          {
-            if ((length > 0) ||
-                (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
-               png_benign_error(png_ptr, "Too many IDATs found");
+            if ((length > 0 && !(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+                || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
+               png_benign_error(png_ptr, ".Too many IDATs found");
          }
          png_handle_unknown(png_ptr, info_ptr, length, keep);
          if (chunk_name == png_PLTE)
@@ -812,10 +818,14 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
       else if (chunk_name == png_IDAT)
       {
          /* Zero length IDATs are legal after the last IDAT has been
-          * read, but not after other chunks have been read.
+          * read, but not after other chunks have been read.  1.6 does not
+          * always read all the deflate data; specifically it cannot be relied
+          * upon to read the Adler32 at the end.  If it doesn't ignore IDAT
+          * chunks which are longer than zero as well:
           */
-         if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
-            png_benign_error(png_ptr, "Too many IDATs found");
+         if ((length > 0 && !(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+             || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
+            png_benign_error(png_ptr, "..Too many IDATs found");
 
          png_crc_finish(png_ptr, length);
       }
@@ -3848,16 +3858,16 @@ png_image_read_direct(png_voidp argument)
             else
                filler = 255;
 
-#           ifdef PNG_FORMAT_AFIRST_SUPPORTED
-               if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
-               {
-                  where = PNG_FILLER_BEFORE;
-                  change &= ~PNG_FORMAT_FLAG_AFIRST;
-               }
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
+            if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
+            {
+               where = PNG_FILLER_BEFORE;
+               change &= ~PNG_FORMAT_FLAG_AFIRST;
+            }
 
-               else
-#           endif
-               where = PNG_FILLER_AFTER;
+            else
+#endif
+            where = PNG_FILLER_AFTER;
 
             png_set_add_alpha(png_ptr, filler, where);
          }
@@ -3965,12 +3975,12 @@ png_image_read_direct(png_voidp argument)
       if (info_ptr->bit_depth == 16)
          info_format |= PNG_FORMAT_FLAG_LINEAR;
 
-#     ifdef PNG_FORMAT_BGR_SUPPORTED
-         if ((png_ptr->transformations & PNG_BGR) != 0)
-            info_format |= PNG_FORMAT_FLAG_BGR;
-#     endif
+#ifdef PNG_FORMAT_BGR_SUPPORTED
+      if ((png_ptr->transformations & PNG_BGR) != 0)
+         info_format |= PNG_FORMAT_FLAG_BGR;
+#endif
 
-#     ifdef PNG_FORMAT_AFIRST_SUPPORTED
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
          if (do_local_background == 2)
          {
             if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
@@ -4071,58 +4081,84 @@ png_image_finish_read(png_imagep image, png_const_colorp background,
 {
    if (image != NULL && image->version == PNG_IMAGE_VERSION)
    {
-      png_uint_32 check;
+      /* Check for row_stride overflow.  This check is not performed on the
+       * original PNG format because it may not occur in the output PNG format
+       * and libpng deals with the issues of reading the original.
+       */
+      const unsigned int channels = PNG_IMAGE_PIXEL_CHANNELS(image->format);
 
-      if (row_stride == 0)
-         row_stride = PNG_IMAGE_ROW_STRIDE(*image);
-
-      if (row_stride < 0)
-         check = -row_stride;
-
-      else
-         check = row_stride;
-
-      if (image->opaque != NULL && buffer != NULL &&
-         check >= PNG_IMAGE_ROW_STRIDE(*image))
+      if (image->width <= 0x7FFFFFFFU/channels) /* no overflow */
       {
-         if ((image->format & PNG_FORMAT_FLAG_COLORMAP) == 0 ||
-            (image->colormap_entries > 0 && colormap != NULL))
+         png_uint_32 check;
+         const png_uint_32 png_row_stride = image->width * channels;
+
+         if (row_stride == 0)
+            row_stride = (png_int_32)/*SAFE*/png_row_stride;
+
+         if (row_stride < 0)
+            check = -row_stride;
+
+         else
+            check = row_stride;
+
+         if (image->opaque != NULL && buffer != NULL && check >= png_row_stride)
          {
-            int result;
-            png_image_read_control display;
-
-            memset(&display, 0, (sizeof display));
-            display.image = image;
-            display.buffer = buffer;
-            display.row_stride = row_stride;
-            display.colormap = colormap;
-            display.background = background;
-            display.local_row = NULL;
-
-            /* Choose the correct 'end' routine; for the color-map case all the
-             * setup has already been done.
+            /* Now check for overflow of the image buffer calculation; this
+             * limits the whole image size to 32 bits for API compatibility with
+             * the current, 32-bit, PNG_IMAGE_BUFFER_SIZE macro.
              */
-            if ((image->format & PNG_FORMAT_FLAG_COLORMAP) != 0)
-               result =
-                  png_safe_execute(image, png_image_read_colormap, &display) &&
-                  png_safe_execute(image, png_image_read_colormapped, &display);
+            if (image->height <= 0xFFFFFFFF/png_row_stride)
+            {
+               if ((image->format & PNG_FORMAT_FLAG_COLORMAP) == 0 ||
+                  (image->colormap_entries > 0 && colormap != NULL))
+               {
+                  int result;
+                  png_image_read_control display;
+
+                  memset(&display, 0, (sizeof display));
+                  display.image = image;
+                  display.buffer = buffer;
+                  display.row_stride = row_stride;
+                  display.colormap = colormap;
+                  display.background = background;
+                  display.local_row = NULL;
+
+                  /* Choose the correct 'end' routine; for the color-map case
+                   * all the setup has already been done.
+                   */
+                  if ((image->format & PNG_FORMAT_FLAG_COLORMAP) != 0)
+                     result = png_safe_execute(image,
+                                    png_image_read_colormap, &display) &&
+                              png_safe_execute(image,
+                                    png_image_read_colormapped, &display);
+
+                  else
+                     result =
+                        png_safe_execute(image,
+                              png_image_read_direct, &display);
+
+                  png_image_free(image);
+                  return result;
+               }
+
+               else
+                  return png_image_error(image,
+                     "png_image_finish_read[color-map]: no color-map");
+            }
 
             else
-               result =
-                  png_safe_execute(image, png_image_read_direct, &display);
-
-            png_image_free(image);
-            return result;
+               return png_image_error(image,
+                  "png_image_finish_read: image too large");
          }
 
          else
             return png_image_error(image,
-               "png_image_finish_read[color-map]: no color-map");
+               "png_image_finish_read: invalid argument");
       }
 
       else
          return png_image_error(image,
-            "png_image_finish_read: invalid argument");
+            "png_image_finish_read: row_stride too large");
    }
 
    else if (image != NULL)
diff --git a/GRRLIB/lib/png/pngrio.c b/GRRLIB/lib/png/pngrio.c
index 38f7fd4..5101d54 100644
--- a/GRRLIB/lib/png/pngrio.c
+++ b/GRRLIB/lib/png/pngrio.c
@@ -2,7 +2,7 @@
 /* pngrio.c - functions for data input
  *
  * Last changed in libpng 1.6.17 [March 26, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
diff --git a/GRRLIB/lib/png/pngrtran.c b/GRRLIB/lib/png/pngrtran.c
index f129ef1..3138147 100644
--- a/GRRLIB/lib/png/pngrtran.c
+++ b/GRRLIB/lib/png/pngrtran.c
@@ -1,8 +1,8 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.6.19 [November 12, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -159,7 +159,7 @@ png_set_background(png_structrp png_ptr,
    png_set_background_fixed(png_ptr, background_color, background_gamma_code,
       need_expand, png_fixed(png_ptr, background_gamma, "png_set_background"));
 }
-#  endif  /* FLOATING_POINT */
+#  endif /* FLOATING_POINT */
 #endif /* READ_BACKGROUND */
 
 /* Scale 16-bit depth files to 8-bit depth.  If both of these are set then the
@@ -289,9 +289,12 @@ png_set_alpha_mode_fixed(png_structrp png_ptr, int mode,
     * is expected to be 1 or greater, but this range test allows for some
     * viewing correction values.  The intent is to weed out users of this API
     * who use the inverse of the gamma value accidentally!  Since some of these
-    * values are reasonable this may have to be changed.
+    * values are reasonable this may have to be changed:
+    *
+    * 1.6.x: changed from 0.07..3 to 0.01..100 (to accomodate the optimal 16-bit
+    * gamma of 36, and its reciprocal.)
     */
-   if (output_gamma < 70000 || output_gamma > 300000)
+   if (output_gamma < 1000 || output_gamma > 10000000)
       png_error(png_ptr, "output gamma out of expected range");
 
    /* The default file gamma is the inverse of the output gamma; the output
@@ -1912,7 +1915,7 @@ png_init_read_transformations(png_structrp png_ptr)
             png_ptr->palette[i].blue = (png_byte)component;
          }
    }
-#endif  /* READ_SHIFT */
+#endif /* READ_SHIFT */
 }
 
 /* Modify the info structure to reflect the transformations.  The
diff --git a/GRRLIB/lib/png/pngrutil.c b/GRRLIB/lib/png/pngrutil.c
index 6189251..c9747fc 100644
--- a/GRRLIB/lib/png/pngrutil.c
+++ b/GRRLIB/lib/png/pngrutil.c
@@ -1,8 +1,8 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.6.20 [December 3, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.20 [December 3, 2014]
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
diff --git a/GRRLIB/lib/png/pngset.c b/GRRLIB/lib/png/pngset.c
index 8fd7965..43456b7 100644
--- a/GRRLIB/lib/png/pngset.c
+++ b/GRRLIB/lib/png/pngset.c
@@ -1,8 +1,8 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.6.19 [November 12, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.23 [June 9, 2016]
+ * Copyright (c) 1998-2016 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.)
  *
@@ -952,12 +952,14 @@ png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
 
        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
 
-       /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
-       png_ptr->trans_alpha = info_ptr->trans_alpha = png_voidcast(png_bytep,
-         png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
-
        if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
+       {
+         /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
+          info_ptr->trans_alpha = png_voidcast(png_bytep,
+             png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
           memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
+       }
+       png_ptr->trans_alpha = info_ptr->trans_alpha;
    }
 
    if (trans_color != NULL)
@@ -1644,4 +1646,88 @@ png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
       png_ptr->num_palette_max = -1;
 }
 #endif
+
+#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_pCAL_SUPPORTED) || \
+    defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
+/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
+ * and if invalid, correct the keyword rather than discarding the entire
+ * chunk.  The PNG 1.0 specification requires keywords 1-79 characters in
+ * length, forbids leading or trailing whitespace, multiple internal spaces,
+ * and the non-break space (0x80) from ISO 8859-1.  Returns keyword length.
+ *
+ * The 'new_key' buffer must be 80 characters in size (for the keyword plus a
+ * trailing '\0').  If this routine returns 0 then there was no keyword, or a
+ * valid one could not be generated, and the caller must png_error.
+ */
+png_uint_32 /* PRIVATE */
+png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
+{
+   png_const_charp orig_key = key;
+   png_uint_32 key_len = 0;
+   int bad_character = 0;
+   int space = 1;
+
+   png_debug(1, "in png_check_keyword");
+
+   if (key == NULL)
+   {
+      *new_key = 0;
+      return 0;
+   }
+
+   while (*key && key_len < 79)
+   {
+      png_byte ch = (png_byte)*key++;
+
+      if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
+         *new_key++ = ch, ++key_len, space = 0;
+
+      else if (space == 0)
+      {
+         /* A space or an invalid character when one wasn't seen immediately
+          * before; output just a space.
+          */
+         *new_key++ = 32, ++key_len, space = 1;
+
+         /* If the character was not a space then it is invalid. */
+         if (ch != 32)
+            bad_character = ch;
+      }
+
+      else if (bad_character == 0)
+         bad_character = ch; /* just skip it, record the first error */
+   }
+
+   if (key_len > 0 && space != 0) /* trailing space */
+   {
+      --key_len, --new_key;
+      if (bad_character == 0)
+         bad_character = 32;
+   }
+
+   /* Terminate the keyword */
+   *new_key = 0;
+
+   if (key_len == 0)
+      return 0;
+
+#ifdef PNG_WARNINGS_SUPPORTED
+   /* Try to only output one warning per keyword: */
+   if (*key != 0) /* keyword too long */
+      png_warning(png_ptr, "keyword truncated");
+
+   else if (bad_character != 0)
+   {
+      PNG_WARNING_PARAMETERS(p)
+
+      png_warning_parameter(p, 1, orig_key);
+      png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);
+
+      png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
+   }
+#endif /* WARNINGS */
+
+   return key_len;
+}
+#endif /* TEXT || pCAL || iCCP || sPLT */
 #endif /* READ || WRITE */
diff --git a/GRRLIB/lib/png/pngstruct.h b/GRRLIB/lib/png/pngstruct.h
index d0bcc79..c1f35ed 100644
--- a/GRRLIB/lib/png/pngstruct.h
+++ b/GRRLIB/lib/png/pngstruct.h
@@ -2,7 +2,7 @@
 /* pngstruct.h - header file for PNG reference library
  *
  * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
diff --git a/GRRLIB/lib/png/pngtrans.c b/GRRLIB/lib/png/pngtrans.c
index 0c0d92d..7f8cc45 100644
--- a/GRRLIB/lib/png/pngtrans.c
+++ b/GRRLIB/lib/png/pngtrans.c
@@ -2,7 +2,7 @@
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
  * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
diff --git a/GRRLIB/lib/png/pngwio.c b/GRRLIB/lib/png/pngwio.c
index db76e6b..586c03b 100644
--- a/GRRLIB/lib/png/pngwio.c
+++ b/GRRLIB/lib/png/pngwio.c
@@ -2,7 +2,7 @@
 /* pngwio.c - functions for data output
  *
  * Last changed in libpng 1.6.15 [November 20, 2014]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2014 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.)
  *
diff --git a/GRRLIB/lib/png/pngwrite.c b/GRRLIB/lib/png/pngwrite.c
index 0d4ee9f..181a899 100644
--- a/GRRLIB/lib/png/pngwrite.c
+++ b/GRRLIB/lib/png/pngwrite.c
@@ -2,7 +2,7 @@
 /* pngwrite.c - general routines to write a PNG file
  *
  * Last changed in libpng 1.6.19 [November 12, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
@@ -12,9 +12,9 @@
  */
 
 #include "pngpriv.h"
-#if defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) && defined(PNG_STDIO_SUPPORTED)
+#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
 #  include <errno.h>
-#endif
+#endif /* SIMPLIFIED_WRITE_STDIO */
 
 #ifdef PNG_WRITE_SUPPORTED
 
@@ -1452,7 +1452,6 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
 
 
 #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
-# ifdef PNG_STDIO_SUPPORTED /* currently required for png_image_write_* */
 /* Initialize the write structure - general purpose utility. */
 static int
 png_image_write_init(png_imagep image)
@@ -1504,6 +1503,10 @@ typedef struct
    png_const_voidp first_row;
    ptrdiff_t       row_bytes;
    png_voidp       local_row;
+   /* Byte count for memory writing */
+   png_bytep        memory;
+   png_alloc_size_t memory_bytes; /* not used for STDIO */
+   png_alloc_size_t output_bytes; /* running total */
 } png_image_write_control;
 
 /* Write png_uint_16 input to a 16-bit PNG; the png_ptr has already been set to
@@ -1931,9 +1934,43 @@ png_image_write_main(png_voidp argument)
       png_set_benign_errors(png_ptr, 0/*error*/);
 #   endif
 
-   /* Default the 'row_stride' parameter if required. */
-   if (display->row_stride == 0)
-      display->row_stride = PNG_IMAGE_ROW_STRIDE(*image);
+   /* Default the 'row_stride' parameter if required, also check the row stride
+    * and total image size to ensure that they are within the system limits.
+    */
+   {
+      const unsigned int channels = PNG_IMAGE_PIXEL_CHANNELS(image->format);
+
+      if (image->width <= 0x7FFFFFFFU/channels) /* no overflow */
+      {
+         png_uint_32 check;
+         const png_uint_32 png_row_stride = image->width * channels;
+
+         if (display->row_stride == 0)
+            display->row_stride = (png_int_32)/*SAFE*/png_row_stride;
+
+         if (display->row_stride < 0)
+            check = -display->row_stride;
+
+         else
+            check = display->row_stride;
+
+         if (check >= png_row_stride)
+         {
+            /* Now check for overflow of the image buffer calculation; this
+             * limits the whole image size to 32 bits for API compatibility with
+             * the current, 32-bit, PNG_IMAGE_BUFFER_SIZE macro.
+             */
+            if (image->height > 0xFFFFFFFF/png_row_stride)
+               png_error(image->opaque->png_ptr, "memory image too large");
+         }
+
+         else
+            png_error(image->opaque->png_ptr, "supplied row stride too small");
+      }
+
+      else
+         png_error(image->opaque->png_ptr, "image row stride too large");
+   }
 
    /* Set the required transforms then write the rows in the correct order. */
    if ((format & PNG_FORMAT_FLAG_COLORMAP) != 0)
@@ -2110,6 +2147,122 @@ png_image_write_main(png_voidp argument)
    return 1;
 }
 
+
+static void (PNGCBAPI
+image_memory_write)(png_structp png_ptr, png_bytep/*const*/ data,
+   png_size_t size)
+{
+   png_image_write_control *display = png_voidcast(png_image_write_control*,
+      png_ptr->io_ptr/*backdoor: png_get_io_ptr(png_ptr)*/);
+   const png_alloc_size_t ob = display->output_bytes;
+
+   /* Check for overflow; this should never happen: */
+   if (size <= ((png_alloc_size_t)-1) - ob)
+   {
+      /* I don't think libpng ever does this, but just in case: */
+      if (size > 0)
+      {
+         if (display->memory_bytes >= ob+size) /* writing */
+            memcpy(display->memory+ob, data, size);
+
+         /* Always update the size: */
+         display->output_bytes = ob+size;
+      }
+   }
+
+   else
+      png_error(png_ptr, "png_image_write_to_memory: PNG too big");
+}
+
+static void (PNGCBAPI
+image_memory_flush)(png_structp png_ptr)
+{
+   PNG_UNUSED(png_ptr)
+}
+
+static int
+png_image_write_memory(png_voidp argument)
+{
+   png_image_write_control *display = png_voidcast(png_image_write_control*,
+      argument);
+
+   /* The rest of the memory-specific init and write_main in an error protected
+    * environment.  This case needs to use callbacks for the write operations
+    * since libpng has no built in support for writing to memory.
+    */
+   png_set_write_fn(display->image->opaque->png_ptr, display/*io_ptr*/,
+         image_memory_write, image_memory_flush);
+
+   return png_image_write_main(display);
+}
+
+int PNGAPI
+png_image_write_to_memory(png_imagep image, void *memory,
+   png_alloc_size_t * PNG_RESTRICT memory_bytes, int convert_to_8bit,
+   const void *buffer, png_int_32 row_stride, const void *colormap)
+{
+   /* Write the image to the given buffer, or count the bytes if it is NULL */
+   if (image != NULL && image->version == PNG_IMAGE_VERSION)
+   {
+      if (memory_bytes != NULL && buffer != NULL)
+      {
+         /* This is to give the caller an easier error detection in the NULL
+          * case and guard against uninitialized variable problems:
+          */
+         if (memory == NULL)
+            *memory_bytes = 0;
+
+         if (png_image_write_init(image) != 0)
+         {
+            png_image_write_control display;
+            int result;
+
+            memset(&display, 0, (sizeof display));
+            display.image = image;
+            display.buffer = buffer;
+            display.row_stride = row_stride;
+            display.colormap = colormap;
+            display.convert_to_8bit = convert_to_8bit;
+            display.memory = png_voidcast(png_bytep, memory);
+            display.memory_bytes = *memory_bytes;
+            display.output_bytes = 0;
+
+            result = png_safe_execute(image, png_image_write_memory, &display);
+            png_image_free(image);
+
+            /* write_memory returns true even if we ran out of buffer. */
+            if (result)
+            {
+               /* On out-of-buffer this function returns '0' but still updates
+                * memory_bytes:
+                */
+               if (memory != NULL && display.output_bytes > *memory_bytes)
+                  result = 0;
+
+               *memory_bytes = display.output_bytes;
+            }
+
+            return result;
+         }
+
+         else
+            return 0;
+      }
+
+      else
+         return png_image_error(image,
+            "png_image_write_to_memory: invalid argument");
+   }
+
+   else if (image != NULL)
+      return png_image_error(image,
+         "png_image_write_to_memory: incorrect PNG_IMAGE_VERSION");
+
+   else
+      return 0;
+}
+
+#ifdef PNG_SIMPLIFIED_WRITE_STDIO_SUPPORTED
 int PNGAPI
 png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
    const void *buffer, png_int_32 row_stride, const void *colormap)
@@ -2117,7 +2270,7 @@ png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
    /* Write the image to the given (FILE*). */
    if (image != NULL && image->version == PNG_IMAGE_VERSION)
    {
-      if (file != NULL)
+      if (file != NULL && buffer != NULL)
       {
          if (png_image_write_init(image) != 0)
          {
@@ -2167,7 +2320,7 @@ png_image_write_to_file(png_imagep image, const char *file_name,
    /* Write the image to the named file. */
    if (image != NULL && image->version == PNG_IMAGE_VERSION)
    {
-      if (file_name != NULL)
+      if (file_name != NULL && buffer != NULL)
       {
          FILE *fp = fopen(file_name, "wb");
 
@@ -2225,6 +2378,6 @@ png_image_write_to_file(png_imagep image, const char *file_name,
    else
       return 0;
 }
-# endif /* STDIO */
+#endif /* SIMPLIFIED_WRITE_STDIO */
 #endif /* SIMPLIFIED_WRITE */
 #endif /* WRITE */
diff --git a/GRRLIB/lib/png/pngwtran.c b/GRRLIB/lib/png/pngwtran.c
index 5dc9491..038a2ef 100644
--- a/GRRLIB/lib/png/pngwtran.c
+++ b/GRRLIB/lib/png/pngwtran.c
@@ -2,7 +2,7 @@
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
  * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2015 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.)
  *
diff --git a/GRRLIB/lib/png/pngwutil.c b/GRRLIB/lib/png/pngwutil.c
index 0ee102b..b47f119 100644
--- a/GRRLIB/lib/png/pngwutil.c
+++ b/GRRLIB/lib/png/pngwutil.c
@@ -1,8 +1,8 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * Last changed in libpng 1.6.19 [November 12, 2015]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.22 [May 26, 2016]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -23,10 +23,10 @@
 void PNGAPI
 png_save_uint_32(png_bytep buf, png_uint_32 i)
 {
-   buf[0] = (png_byte)(i >> 24);
-   buf[1] = (png_byte)(i >> 16);
-   buf[2] = (png_byte)(i >> 8);
-   buf[3] = (png_byte)(i     );
+   buf[0] = (png_byte)((i >> 24) & 0xffU);
+   buf[1] = (png_byte)((i >> 16) & 0xffU);
+   buf[2] = (png_byte)((i >>  8) & 0xffU);
+   buf[3] = (png_byte)( i        & 0xffU);
 }
 
 /* Place a 16-bit number into a buffer in PNG byte order.
@@ -36,8 +36,8 @@ png_save_uint_32(png_bytep buf, png_uint_32 i)
 void PNGAPI
 png_save_uint_16(png_bytep buf, unsigned int i)
 {
-   buf[0] = (png_byte)(i >> 8);
-   buf[1] = (png_byte)(i     );
+   buf[0] = (png_byte)((i >> 8) & 0xffU);
+   buf[1] = (png_byte)( i       & 0xffU);
 }
 #endif
 
@@ -665,90 +665,6 @@ png_write_compressed_data_out(png_structrp png_ptr, compression_state *comp)
 }
 #endif /* WRITE_COMPRESSED_TEXT */
 
-#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
-    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
-/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
- * and if invalid, correct the keyword rather than discarding the entire
- * chunk.  The PNG 1.0 specification requires keywords 1-79 characters in
- * length, forbids leading or trailing whitespace, multiple internal spaces,
- * and the non-break space (0x80) from ISO 8859-1.  Returns keyword length.
- *
- * The 'new_key' buffer must be 80 characters in size (for the keyword plus a
- * trailing '\0').  If this routine returns 0 then there was no keyword, or a
- * valid one could not be generated, and the caller must png_error.
- */
-static png_uint_32
-png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
-{
-   png_const_charp orig_key = key;
-   png_uint_32 key_len = 0;
-   int bad_character = 0;
-   int space = 1;
-
-   png_debug(1, "in png_check_keyword");
-
-   if (key == NULL)
-   {
-      *new_key = 0;
-      return 0;
-   }
-
-   while (*key && key_len < 79)
-   {
-      png_byte ch = (png_byte)*key++;
-
-      if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
-         *new_key++ = ch, ++key_len, space = 0;
-
-      else if (space == 0)
-      {
-         /* A space or an invalid character when one wasn't seen immediately
-          * before; output just a space.
-          */
-         *new_key++ = 32, ++key_len, space = 1;
-
-         /* If the character was not a space then it is invalid. */
-         if (ch != 32)
-            bad_character = ch;
-      }
-
-      else if (bad_character == 0)
-         bad_character = ch; /* just skip it, record the first error */
-   }
-
-   if (key_len > 0 && space != 0) /* trailing space */
-   {
-      --key_len, --new_key;
-      if (bad_character == 0)
-         bad_character = 32;
-   }
-
-   /* Terminate the keyword */
-   *new_key = 0;
-
-   if (key_len == 0)
-      return 0;
-
-#ifdef PNG_WARNINGS_SUPPORTED
-   /* Try to only output one warning per keyword: */
-   if (*key != 0) /* keyword too long */
-      png_warning(png_ptr, "keyword truncated");
-
-   else if (bad_character != 0)
-   {
-      PNG_WARNING_PARAMETERS(p)
-
-      png_warning_parameter(p, 1, orig_key);
-      png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);
-
-      png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
-   }
-#endif /* WARNINGS */
-
-   return key_len;
-}
-#endif /* WRITE_TEXT || WRITE_pCAL || WRITE_iCCP || WRITE_sPLT */
-
 /* Write the IHDR chunk, and update the png_struct with the necessary
  * information.  Note that the rest of this code depends upon this
  * information being correct.