Remove damned ancient DOS line endings from Irrlicht. Hopefully I did not go overboard.

1 files changed, 1655 insertions, 1655 deletions

diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwrite.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwrite.c
index dc12a20..6d3fd4c 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwrite.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwrite.c
@@ -1,1655 +1,1655 @@
-

-/* pngwrite.c - general routines to write a PNG file

- *

- * Last changed in libpng 1.5.7 [December 15, 2011]

- * Copyright (c) 1998-2011 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.)

- *

- * This code is released under the libpng license.

- * For conditions of distribution and use, see the disclaimer

- * and license in png.h

- */

-

-#include "pngpriv.h"

-

-#ifdef PNG_WRITE_SUPPORTED

-

-/* Writes all the PNG information.  This is the suggested way to use the

- * library.  If you have a new chunk to add, make a function to write it,

- * and put it in the correct location here.  If you want the chunk written

- * after the image data, put it in png_write_end().  I strongly encourage

- * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing

- * the chunk, as that will keep the code from breaking if you want to just

- * write a plain PNG file.  If you have long comments, I suggest writing

- * them in png_write_end(), and compressing them.

- */

-void PNGAPI

-png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)

-{

-   png_debug(1, "in png_write_info_before_PLTE");

-

-   if (png_ptr == NULL || info_ptr == NULL)

-      return;

-

-   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))

-   {

-   /* Write PNG signature */

-   png_write_sig(png_ptr);

-

-#ifdef PNG_MNG_FEATURES_SUPPORTED

-   if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \

-       (png_ptr->mng_features_permitted))

-   {

-      png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");

-      png_ptr->mng_features_permitted = 0;

-   }

-#endif

-

-   /* Write IHDR information. */

-   png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,

-       info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,

-       info_ptr->filter_type,

-#ifdef PNG_WRITE_INTERLACING_SUPPORTED

-       info_ptr->interlace_type);

-#else

-       0);

-#endif

-   /* The rest of these check to see if the valid field has the appropriate

-    * flag set, and if it does, writes the chunk.

-    */

-#ifdef PNG_WRITE_gAMA_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_gAMA)

-      png_write_gAMA_fixed(png_ptr, info_ptr->gamma);

-#endif

-#ifdef PNG_WRITE_sRGB_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_sRGB)

-      png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);

-#endif

-

-#ifdef PNG_WRITE_iCCP_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_iCCP)

-      png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,

-          (png_charp)info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);

-#endif

-#ifdef PNG_WRITE_sBIT_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_sBIT)

-      png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);

-#endif

-#ifdef PNG_WRITE_cHRM_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_cHRM)

-      png_write_cHRM_fixed(png_ptr,

-          info_ptr->x_white, info_ptr->y_white,

-          info_ptr->x_red, info_ptr->y_red,

-          info_ptr->x_green, info_ptr->y_green,

-          info_ptr->x_blue, info_ptr->y_blue);

-#endif

-

-#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED

-   if (info_ptr->unknown_chunks_num)

-   {

-      png_unknown_chunk *up;

-

-      png_debug(5, "writing extra chunks");

-

-      for (up = info_ptr->unknown_chunks;

-           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;

-           up++)

-      {

-         int keep = png_handle_as_unknown(png_ptr, up->name);

-

-         if (keep != PNG_HANDLE_CHUNK_NEVER &&

-             up->location &&

-             !(up->location & PNG_HAVE_PLTE) &&

-             !(up->location & PNG_HAVE_IDAT) &&

-             !(up->location & PNG_AFTER_IDAT) &&

-             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||

-             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))

-         {

-            if (up->size == 0)

-               png_warning(png_ptr, "Writing zero-length unknown chunk");

-

-            png_write_chunk(png_ptr, up->name, up->data, up->size);

-         }

-      }

-   }

-#endif

-      png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;

-   }

-}

-

-void PNGAPI

-png_write_info(png_structp png_ptr, png_infop info_ptr)

-{

-#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)

-   int i;

-#endif

-

-   png_debug(1, "in png_write_info");

-

-   if (png_ptr == NULL || info_ptr == NULL)

-      return;

-

-   png_write_info_before_PLTE(png_ptr, info_ptr);

-

-   if (info_ptr->valid & PNG_INFO_PLTE)

-      png_write_PLTE(png_ptr, info_ptr->palette,

-          (png_uint_32)info_ptr->num_palette);

-

-   else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)

-      png_error(png_ptr, "Valid palette required for paletted images");

-

-#ifdef PNG_WRITE_tRNS_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_tRNS)

-   {

-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED

-      /* Invert the alpha channel (in tRNS) */

-      if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&

-          info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)

-      {

-         int j;

-         for (j = 0; j<(int)info_ptr->num_trans; j++)

-            info_ptr->trans_alpha[j] =

-               (png_byte)(255 - info_ptr->trans_alpha[j]);

-      }

-#endif

-      png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color),

-          info_ptr->num_trans, info_ptr->color_type);

-   }

-#endif

-#ifdef PNG_WRITE_bKGD_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_bKGD)

-      png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);

-#endif

-

-#ifdef PNG_WRITE_hIST_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_hIST)

-      png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);

-#endif

-

-#ifdef PNG_WRITE_oFFs_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_oFFs)

-      png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,

-          info_ptr->offset_unit_type);

-#endif

-

-#ifdef PNG_WRITE_pCAL_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_pCAL)

-      png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,

-          info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,

-          info_ptr->pcal_units, info_ptr->pcal_params);

-#endif

-

-#ifdef PNG_WRITE_sCAL_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_sCAL)

-      png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,

-          info_ptr->scal_s_width, info_ptr->scal_s_height);

-#endif /* sCAL */

-

-#ifdef PNG_WRITE_pHYs_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_pHYs)

-      png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,

-          info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);

-#endif /* pHYs */

-

-#ifdef PNG_WRITE_tIME_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_tIME)

-   {

-      png_write_tIME(png_ptr, &(info_ptr->mod_time));

-      png_ptr->mode |= PNG_WROTE_tIME;

-   }

-#endif /* tIME */

-

-#ifdef PNG_WRITE_sPLT_SUPPORTED

-   if (info_ptr->valid & PNG_INFO_sPLT)

-      for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)

-         png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);

-#endif /* sPLT */

-

-#ifdef PNG_WRITE_TEXT_SUPPORTED

-   /* Check to see if we need to write text chunks */

-   for (i = 0; i < info_ptr->num_text; i++)

-   {

-      png_debug2(2, "Writing header text chunk %d, type %d", i,

-          info_ptr->text[i].compression);

-      /* An internationalized chunk? */

-      if (info_ptr->text[i].compression > 0)

-      {

-#ifdef PNG_WRITE_iTXt_SUPPORTED

-         /* Write international chunk */

-         png_write_iTXt(png_ptr,

-             info_ptr->text[i].compression,

-             info_ptr->text[i].key,

-             info_ptr->text[i].lang,

-             info_ptr->text[i].lang_key,

-             info_ptr->text[i].text);

-#else

-          png_warning(png_ptr, "Unable to write international text");

-#endif

-          /* Mark this chunk as written */

-          info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

-      }

-

-      /* If we want a compressed text chunk */

-      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)

-      {

-#ifdef PNG_WRITE_zTXt_SUPPORTED

-         /* Write compressed chunk */

-         png_write_zTXt(png_ptr, info_ptr->text[i].key,

-             info_ptr->text[i].text, 0,

-             info_ptr->text[i].compression);

-#else

-         png_warning(png_ptr, "Unable to write compressed text");

-#endif

-         /* Mark this chunk as written */

-         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;

-      }

-

-      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)

-      {

-#ifdef PNG_WRITE_tEXt_SUPPORTED

-         /* Write uncompressed chunk */

-         png_write_tEXt(png_ptr, info_ptr->text[i].key,

-             info_ptr->text[i].text,

-             0);

-         /* Mark this chunk as written */

-         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

-#else

-         /* Can't get here */

-         png_warning(png_ptr, "Unable to write uncompressed text");

-#endif

-      }

-   }

-#endif /* tEXt */

-

-#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED

-   if (info_ptr->unknown_chunks_num)

-   {

-      png_unknown_chunk *up;

-

-      png_debug(5, "writing extra chunks");

-

-      for (up = info_ptr->unknown_chunks;

-           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;

-           up++)

-      {

-         int keep = png_handle_as_unknown(png_ptr, up->name);

-         if (keep != PNG_HANDLE_CHUNK_NEVER &&

-             up->location &&

-             (up->location & PNG_HAVE_PLTE) &&

-             !(up->location & PNG_HAVE_IDAT) &&

-             !(up->location & PNG_AFTER_IDAT) &&

-             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||

-             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))

-         {

-            png_write_chunk(png_ptr, up->name, up->data, up->size);

-         }

-      }

-   }

-#endif

-}

-

-/* Writes the end of the PNG file.  If you don't want to write comments or

- * time information, you can pass NULL for info.  If you already wrote these

- * in png_write_info(), do not write them again here.  If you have long

- * comments, I suggest writing them here, and compressing them.

- */

-void PNGAPI

-png_write_end(png_structp png_ptr, png_infop info_ptr)

-{

-   png_debug(1, "in png_write_end");

-

-   if (png_ptr == NULL)

-      return;

-

-   if (!(png_ptr->mode & PNG_HAVE_IDAT))

-      png_error(png_ptr, "No IDATs written into file");

-

-   /* See if user wants us to write information chunks */

-   if (info_ptr != NULL)

-   {

-#ifdef PNG_WRITE_TEXT_SUPPORTED

-      int i; /* local index variable */

-#endif

-#ifdef PNG_WRITE_tIME_SUPPORTED

-      /* Check to see if user has supplied a time chunk */

-      if ((info_ptr->valid & PNG_INFO_tIME) &&

-          !(png_ptr->mode & PNG_WROTE_tIME))

-         png_write_tIME(png_ptr, &(info_ptr->mod_time));

-

-#endif

-#ifdef PNG_WRITE_TEXT_SUPPORTED

-      /* Loop through comment chunks */

-      for (i = 0; i < info_ptr->num_text; i++)

-      {

-         png_debug2(2, "Writing trailer text chunk %d, type %d", i,

-            info_ptr->text[i].compression);

-         /* An internationalized chunk? */

-         if (info_ptr->text[i].compression > 0)

-         {

-#ifdef PNG_WRITE_iTXt_SUPPORTED

-            /* Write international chunk */

-            png_write_iTXt(png_ptr,

-                info_ptr->text[i].compression,

-                info_ptr->text[i].key,

-                info_ptr->text[i].lang,

-                info_ptr->text[i].lang_key,

-                info_ptr->text[i].text);

-#else

-            png_warning(png_ptr, "Unable to write international text");

-#endif

-            /* Mark this chunk as written */

-            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

-         }

-

-         else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)

-         {

-#ifdef PNG_WRITE_zTXt_SUPPORTED

-            /* Write compressed chunk */

-            png_write_zTXt(png_ptr, info_ptr->text[i].key,

-                info_ptr->text[i].text, 0,

-                info_ptr->text[i].compression);

-#else

-            png_warning(png_ptr, "Unable to write compressed text");

-#endif

-            /* Mark this chunk as written */

-            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;

-         }

-

-         else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)

-         {

-#ifdef PNG_WRITE_tEXt_SUPPORTED

-            /* Write uncompressed chunk */

-            png_write_tEXt(png_ptr, info_ptr->text[i].key,

-                info_ptr->text[i].text, 0);

-#else

-            png_warning(png_ptr, "Unable to write uncompressed text");

-#endif

-

-            /* Mark this chunk as written */

-            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;

-         }

-      }

-#endif

-#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED

-   if (info_ptr->unknown_chunks_num)

-   {

-      png_unknown_chunk *up;

-

-      png_debug(5, "writing extra chunks");

-

-      for (up = info_ptr->unknown_chunks;

-           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;

-           up++)

-      {

-         int keep = png_handle_as_unknown(png_ptr, up->name);

-         if (keep != PNG_HANDLE_CHUNK_NEVER &&

-             up->location &&

-             (up->location & PNG_AFTER_IDAT) &&

-             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||

-             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))

-         {

-            png_write_chunk(png_ptr, up->name, up->data, up->size);

-         }

-      }

-   }

-#endif

-   }

-

-   png_ptr->mode |= PNG_AFTER_IDAT;

-

-   /* Write end of PNG file */

-   png_write_IEND(png_ptr);

-   /* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03,

-    * and restored again in libpng-1.2.30, may cause some applications that

-    * do not set png_ptr->output_flush_fn to crash.  If your application

-    * experiences a problem, please try building libpng with

-    * PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to

-    * png-mng-implement at lists.sf.net .

-    */

-#ifdef PNG_WRITE_FLUSH_SUPPORTED

-#  ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED

-   png_flush(png_ptr);

-#  endif

-#endif

-}

-

-#ifdef PNG_CONVERT_tIME_SUPPORTED

-/* "tm" structure is not supported on WindowsCE */

-void PNGAPI

-png_convert_from_struct_tm(png_timep ptime, PNG_CONST struct tm FAR * ttime)

-{

-   png_debug(1, "in png_convert_from_struct_tm");

-

-   ptime->year = (png_uint_16)(1900 + ttime->tm_year);

-   ptime->month = (png_byte)(ttime->tm_mon + 1);

-   ptime->day = (png_byte)ttime->tm_mday;

-   ptime->hour = (png_byte)ttime->tm_hour;

-   ptime->minute = (png_byte)ttime->tm_min;

-   ptime->second = (png_byte)ttime->tm_sec;

-}

-

-void PNGAPI

-png_convert_from_time_t(png_timep ptime, time_t ttime)

-{

-   struct tm *tbuf;

-

-   png_debug(1, "in png_convert_from_time_t");

-

-   tbuf = gmtime(&ttime);

-   png_convert_from_struct_tm(ptime, tbuf);

-}

-#endif

-

-/* Initialize png_ptr structure, and allocate any memory needed */

-PNG_FUNCTION(png_structp,PNGAPI

-png_create_write_struct,(png_const_charp user_png_ver, png_voidp error_ptr,

-    png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED)

-{

-#ifdef PNG_USER_MEM_SUPPORTED

-   return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,

-       warn_fn, NULL, NULL, NULL));

-}

-

-/* Alternate initialize png_ptr structure, and allocate any memory needed */

-static void png_reset_filter_heuristics(png_structp png_ptr); /* forward decl */

-

-PNG_FUNCTION(png_structp,PNGAPI

-png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,

-    png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,

-    png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED)

-{

-#endif /* PNG_USER_MEM_SUPPORTED */

-   volatile int png_cleanup_needed = 0;

-#ifdef PNG_SETJMP_SUPPORTED

-   volatile

-#endif

-   png_structp png_ptr;

-#ifdef PNG_SETJMP_SUPPORTED

-#ifdef USE_FAR_KEYWORD

-   jmp_buf tmp_jmpbuf;

-#endif

-#endif

-

-   png_debug(1, "in png_create_write_struct");

-

-#ifdef PNG_USER_MEM_SUPPORTED

-   png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,

-       (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);

-#else

-   png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);

-#endif /* PNG_USER_MEM_SUPPORTED */

-   if (png_ptr == NULL)

-      return (NULL);

-

-   /* Added at libpng-1.2.6 */

-#ifdef PNG_SET_USER_LIMITS_SUPPORTED

-   png_ptr->user_width_max = PNG_USER_WIDTH_MAX;

-   png_ptr->user_height_max = PNG_USER_HEIGHT_MAX;

-#endif

-

-#ifdef PNG_SETJMP_SUPPORTED

-/* Applications that neglect to set up their own setjmp() and then

- * encounter a png_error() will longjmp here.  Since the jmpbuf is

- * then meaningless we abort instead of returning.

- */

-#ifdef USE_FAR_KEYWORD

-   if (setjmp(tmp_jmpbuf))

-#else

-   if (setjmp(png_jmpbuf(png_ptr))) /* sets longjmp to match setjmp */

-#endif

-#ifdef USE_FAR_KEYWORD

-   png_memcpy(png_jmpbuf(png_ptr), tmp_jmpbuf, png_sizeof(jmp_buf));

-#endif

-      PNG_ABORT();

-#endif

-

-#ifdef PNG_USER_MEM_SUPPORTED

-   png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);

-#endif /* PNG_USER_MEM_SUPPORTED */

-   png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);

-

-   if (!png_user_version_check(png_ptr, user_png_ver))

-      png_cleanup_needed = 1;

-

-   /* Initialize zbuf - compression buffer */

-   png_ptr->zbuf_size = PNG_ZBUF_SIZE;

-

-   if (!png_cleanup_needed)

-   {

-      png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr,

-          png_ptr->zbuf_size);

-      if (png_ptr->zbuf == NULL)

-         png_cleanup_needed = 1;

-   }

-

-   if (png_cleanup_needed)

-   {

-       /* Clean up PNG structure and deallocate any memory. */

-       png_free(png_ptr, png_ptr->zbuf);

-       png_ptr->zbuf = NULL;

-#ifdef PNG_USER_MEM_SUPPORTED

-       png_destroy_struct_2((png_voidp)png_ptr,

-           (png_free_ptr)free_fn, (png_voidp)mem_ptr);

-#else

-       png_destroy_struct((png_voidp)png_ptr);

-#endif

-       return (NULL);

-   }

-

-   png_set_write_fn(png_ptr, NULL, NULL, NULL);

-

-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED

-   png_reset_filter_heuristics(png_ptr);

-#endif

-

-   return (png_ptr);

-}

-

-

-/* Write a few rows of image data.  If the image is interlaced,

- * either you will have to write the 7 sub images, or, if you

- * have called png_set_interlace_handling(), you will have to

- * "write" the image seven times.

- */

-void PNGAPI

-png_write_rows(png_structp png_ptr, png_bytepp row,

-    png_uint_32 num_rows)

-{

-   png_uint_32 i; /* row counter */

-   png_bytepp rp; /* row pointer */

-

-   png_debug(1, "in png_write_rows");

-

-   if (png_ptr == NULL)

-      return;

-

-   /* Loop through the rows */

-   for (i = 0, rp = row; i < num_rows; i++, rp++)

-   {

-      png_write_row(png_ptr, *rp);

-   }

-}

-

-/* Write the image.  You only need to call this function once, even

- * if you are writing an interlaced image.

- */

-void PNGAPI

-png_write_image(png_structp png_ptr, png_bytepp image)

-{

-   png_uint_32 i; /* row index */

-   int pass, num_pass; /* pass variables */

-   png_bytepp rp; /* points to current row */

-

-   if (png_ptr == NULL)

-      return;

-

-   png_debug(1, "in png_write_image");

-

-#ifdef PNG_WRITE_INTERLACING_SUPPORTED

-   /* Initialize interlace handling.  If image is not interlaced,

-    * this will set pass to 1

-    */

-   num_pass = png_set_interlace_handling(png_ptr);

-#else

-   num_pass = 1;

-#endif

-   /* Loop through passes */

-   for (pass = 0; pass < num_pass; pass++)

-   {

-      /* Loop through image */

-      for (i = 0, rp = image; i < png_ptr->height; i++, rp++)

-      {

-         png_write_row(png_ptr, *rp);

-      }

-   }

-}

-

-/* Called by user to write a row of image data */

-void PNGAPI

-png_write_row(png_structp png_ptr, png_const_bytep row)

-{

-   /* 1.5.6: moved from png_struct to be a local structure: */

-   png_row_info row_info;

-

-   if (png_ptr == NULL)

-      return;

-

-   png_debug2(1, "in png_write_row (row %u, pass %d)",

-      png_ptr->row_number, png_ptr->pass);

-

-   /* Initialize transformations and other stuff if first time */

-   if (png_ptr->row_number == 0 && png_ptr->pass == 0)

-   {

-      /* Make sure we wrote the header info */

-      if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))

-         png_error(png_ptr,

-             "png_write_info was never called before png_write_row");

-

-      /* Check for transforms that have been set but were defined out */

-#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)

-      if (png_ptr->transformations & PNG_INVERT_MONO)

-         png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined");

-#endif

-

-#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)

-      if (png_ptr->transformations & PNG_FILLER)

-         png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined");

-#endif

-#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \

-    defined(PNG_READ_PACKSWAP_SUPPORTED)

-      if (png_ptr->transformations & PNG_PACKSWAP)

-         png_warning(png_ptr,

-             "PNG_WRITE_PACKSWAP_SUPPORTED is not defined");

-#endif

-

-#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)

-      if (png_ptr->transformations & PNG_PACK)

-         png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined");

-#endif

-

-#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)

-      if (png_ptr->transformations & PNG_SHIFT)

-         png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined");

-#endif

-

-#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)

-      if (png_ptr->transformations & PNG_BGR)

-         png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined");

-#endif

-

-#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)

-      if (png_ptr->transformations & PNG_SWAP_BYTES)

-         png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined");

-#endif

-

-      png_write_start_row(png_ptr);

-   }

-

-#ifdef PNG_WRITE_INTERLACING_SUPPORTED

-   /* If interlaced and not interested in row, return */

-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))

-   {

-      switch (png_ptr->pass)

-      {

-         case 0:

-            if (png_ptr->row_number & 0x07)

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         case 1:

-            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         case 2:

-            if ((png_ptr->row_number & 0x07) != 4)

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         case 3:

-            if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         case 4:

-            if ((png_ptr->row_number & 0x03) != 2)

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         case 5:

-            if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         case 6:

-            if (!(png_ptr->row_number & 0x01))

-            {

-               png_write_finish_row(png_ptr);

-               return;

-            }

-            break;

-

-         default: /* error: ignore it */

-            break;

-      }

-   }

-#endif

-

-   /* Set up row info for transformations */

-   row_info.color_type = png_ptr->color_type;

-   row_info.width = png_ptr->usr_width;

-   row_info.channels = png_ptr->usr_channels;

-   row_info.bit_depth = png_ptr->usr_bit_depth;

-   row_info.pixel_depth = (png_byte)(row_info.bit_depth * row_info.channels);

-   row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width);

-

-   png_debug1(3, "row_info->color_type = %d", row_info.color_type);

-   png_debug1(3, "row_info->width = %u", row_info.width);

-   png_debug1(3, "row_info->channels = %d", row_info.channels);

-   png_debug1(3, "row_info->bit_depth = %d", row_info.bit_depth);

-   png_debug1(3, "row_info->pixel_depth = %d", row_info.pixel_depth);

-   png_debug1(3, "row_info->rowbytes = %lu", (unsigned long)row_info.rowbytes);

-

-   /* Copy user's row into buffer, leaving room for filter byte. */

-   png_memcpy(png_ptr->row_buf + 1, row, row_info.rowbytes);

-

-#ifdef PNG_WRITE_INTERLACING_SUPPORTED

-   /* Handle interlacing */

-   if (png_ptr->interlaced && png_ptr->pass < 6 &&

-       (png_ptr->transformations & PNG_INTERLACE))

-   {

-      png_do_write_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass);

-      /* This should always get caught above, but still ... */

-      if (!(row_info.width))

-      {

-         png_write_finish_row(png_ptr);

-         return;

-      }

-   }

-#endif

-

-#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED

-   /* Handle other transformations */

-   if (png_ptr->transformations)

-      png_do_write_transformations(png_ptr, &row_info);

-#endif

-

-   /* At this point the row_info pixel depth must match the 'transformed' depth,

-    * which is also the output depth.

-    */

-   if (row_info.pixel_depth != png_ptr->pixel_depth ||

-      row_info.pixel_depth != png_ptr->transformed_pixel_depth)

-      png_error(png_ptr, "internal write transform logic error");

-

-#ifdef PNG_MNG_FEATURES_SUPPORTED

-   /* Write filter_method 64 (intrapixel differencing) only if

-    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and

-    * 2. Libpng did not write a PNG signature (this filter_method is only

-    *    used in PNG datastreams that are embedded in MNG datastreams) and

-    * 3. The application called png_permit_mng_features with a mask that

-    *    included PNG_FLAG_MNG_FILTER_64 and

-    * 4. The filter_method is 64 and

-    * 5. The color_type is RGB or RGBA

-    */

-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&

-       (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))

-   {

-      /* Intrapixel differencing */

-      png_do_write_intrapixel(&row_info, png_ptr->row_buf + 1);

-   }

-#endif

-

-   /* Find a filter if necessary, filter the row and write it out. */

-   png_write_find_filter(png_ptr, &row_info);

-

-   if (png_ptr->write_row_fn != NULL)

-      (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);

-}

-

-#ifdef PNG_WRITE_FLUSH_SUPPORTED

-/* Set the automatic flush interval or 0 to turn flushing off */

-void PNGAPI

-png_set_flush(png_structp png_ptr, int nrows)

-{

-   png_debug(1, "in png_set_flush");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);

-}

-

-/* Flush the current output buffers now */

-void PNGAPI

-png_write_flush(png_structp png_ptr)

-{

-   int wrote_IDAT;

-

-   png_debug(1, "in png_write_flush");

-

-   if (png_ptr == NULL)

-      return;

-

-   /* We have already written out all of the data */

-   if (png_ptr->row_number >= png_ptr->num_rows)

-      return;

-

-   do

-   {

-      int ret;

-

-      /* Compress the data */

-      ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);

-      wrote_IDAT = 0;

-

-      /* Check for compression errors */

-      if (ret != Z_OK)

-      {

-         if (png_ptr->zstream.msg != NULL)

-            png_error(png_ptr, png_ptr->zstream.msg);

-

-         else

-            png_error(png_ptr, "zlib error");

-      }

-

-      if (!(png_ptr->zstream.avail_out))

-      {

-         /* Write the IDAT and reset the zlib output buffer */

-         png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);

-         wrote_IDAT = 1;

-      }

-   } while (wrote_IDAT == 1);

-

-   /* If there is any data left to be output, write it into a new IDAT */

-   if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)

-   {

-      /* Write the IDAT and reset the zlib output buffer */

-      png_write_IDAT(png_ptr, png_ptr->zbuf,

-          png_ptr->zbuf_size - png_ptr->zstream.avail_out);

-   }

-   png_ptr->flush_rows = 0;

-   png_flush(png_ptr);

-}

-#endif /* PNG_WRITE_FLUSH_SUPPORTED */

-

-/* Free all memory used by the write */

-void PNGAPI

-png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)

-{

-   png_structp png_ptr = NULL;

-   png_infop info_ptr = NULL;

-#ifdef PNG_USER_MEM_SUPPORTED

-   png_free_ptr free_fn = NULL;

-   png_voidp mem_ptr = NULL;

-#endif

-

-   png_debug(1, "in png_destroy_write_struct");

-

-   if (png_ptr_ptr != NULL)

-      png_ptr = *png_ptr_ptr;

-

-#ifdef PNG_USER_MEM_SUPPORTED

-   if (png_ptr != NULL)

-   {

-      free_fn = png_ptr->free_fn;

-      mem_ptr = png_ptr->mem_ptr;

-   }

-#endif

-

-   if (info_ptr_ptr != NULL)

-      info_ptr = *info_ptr_ptr;

-

-   if (info_ptr != NULL)

-   {

-      if (png_ptr != NULL)

-      {

-         png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);

-

-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED

-         if (png_ptr->num_chunk_list)

-         {

-            png_free(png_ptr, png_ptr->chunk_list);

-            png_ptr->num_chunk_list = 0;

-         }

-#endif

-      }

-

-#ifdef PNG_USER_MEM_SUPPORTED

-      png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,

-          (png_voidp)mem_ptr);

-#else

-      png_destroy_struct((png_voidp)info_ptr);

-#endif

-      *info_ptr_ptr = NULL;

-   }

-

-   if (png_ptr != NULL)

-   {

-      png_write_destroy(png_ptr);

-#ifdef PNG_USER_MEM_SUPPORTED

-      png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,

-          (png_voidp)mem_ptr);

-#else

-      png_destroy_struct((png_voidp)png_ptr);

-#endif

-      *png_ptr_ptr = NULL;

-   }

-}

-

-

-/* Free any memory used in png_ptr struct (old method) */

-void /* PRIVATE */

-png_write_destroy(png_structp png_ptr)

-{

-#ifdef PNG_SETJMP_SUPPORTED

-   jmp_buf tmp_jmp; /* Save jump buffer */

-#endif

-   png_error_ptr error_fn;

-#ifdef PNG_WARNINGS_SUPPORTED

-   png_error_ptr warning_fn;

-#endif

-   png_voidp error_ptr;

-#ifdef PNG_USER_MEM_SUPPORTED

-   png_free_ptr free_fn;

-#endif

-

-   png_debug(1, "in png_write_destroy");

-

-   /* Free any memory zlib uses */

-   if (png_ptr->zlib_state != PNG_ZLIB_UNINITIALIZED)

-      deflateEnd(&png_ptr->zstream);

-

-   /* Free our memory.  png_free checks NULL for us. */

-   png_free(png_ptr, png_ptr->zbuf);

-   png_free(png_ptr, png_ptr->row_buf);

-#ifdef PNG_WRITE_FILTER_SUPPORTED

-   png_free(png_ptr, png_ptr->prev_row);

-   png_free(png_ptr, png_ptr->sub_row);

-   png_free(png_ptr, png_ptr->up_row);

-   png_free(png_ptr, png_ptr->avg_row);

-   png_free(png_ptr, png_ptr->paeth_row);

-#endif

-

-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED

-   /* Use this to save a little code space, it doesn't free the filter_costs */

-   png_reset_filter_heuristics(png_ptr);

-   png_free(png_ptr, png_ptr->filter_costs);

-   png_free(png_ptr, png_ptr->inv_filter_costs);

-#endif

-

-#ifdef PNG_SETJMP_SUPPORTED

-   /* Reset structure */

-   png_memcpy(tmp_jmp, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));

-#endif

-

-   error_fn = png_ptr->error_fn;

-#ifdef PNG_WARNINGS_SUPPORTED

-   warning_fn = png_ptr->warning_fn;

-#endif

-   error_ptr = png_ptr->error_ptr;

-#ifdef PNG_USER_MEM_SUPPORTED

-   free_fn = png_ptr->free_fn;

-#endif

-

-   png_memset(png_ptr, 0, png_sizeof(png_struct));

-

-   png_ptr->error_fn = error_fn;

-#ifdef PNG_WARNINGS_SUPPORTED

-   png_ptr->warning_fn = warning_fn;

-#endif

-   png_ptr->error_ptr = error_ptr;

-#ifdef PNG_USER_MEM_SUPPORTED

-   png_ptr->free_fn = free_fn;

-#endif

-

-#ifdef PNG_SETJMP_SUPPORTED

-   png_memcpy(png_ptr->longjmp_buffer, tmp_jmp, png_sizeof(jmp_buf));

-#endif

-}

-

-/* Allow the application to select one or more row filters to use. */

-void PNGAPI

-png_set_filter(png_structp png_ptr, int method, int filters)

-{

-   png_debug(1, "in png_set_filter");

-

-   if (png_ptr == NULL)

-      return;

-

-#ifdef PNG_MNG_FEATURES_SUPPORTED

-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&

-       (method == PNG_INTRAPIXEL_DIFFERENCING))

-      method = PNG_FILTER_TYPE_BASE;

-

-#endif

-   if (method == PNG_FILTER_TYPE_BASE)

-   {

-      switch (filters & (PNG_ALL_FILTERS | 0x07))

-      {

-#ifdef PNG_WRITE_FILTER_SUPPORTED

-         case 5:

-         case 6:

-         case 7: png_warning(png_ptr, "Unknown row filter for method 0");

-#endif /* PNG_WRITE_FILTER_SUPPORTED */

-         case PNG_FILTER_VALUE_NONE:

-            png_ptr->do_filter = PNG_FILTER_NONE; break;

-

-#ifdef PNG_WRITE_FILTER_SUPPORTED

-         case PNG_FILTER_VALUE_SUB:

-            png_ptr->do_filter = PNG_FILTER_SUB; break;

-

-         case PNG_FILTER_VALUE_UP:

-            png_ptr->do_filter = PNG_FILTER_UP; break;

-

-         case PNG_FILTER_VALUE_AVG:

-            png_ptr->do_filter = PNG_FILTER_AVG; break;

-

-         case PNG_FILTER_VALUE_PAETH:

-            png_ptr->do_filter = PNG_FILTER_PAETH; break;

-

-         default:

-            png_ptr->do_filter = (png_byte)filters; break;

-#else

-         default:

-            png_warning(png_ptr, "Unknown row filter for method 0");

-#endif /* PNG_WRITE_FILTER_SUPPORTED */

-      }

-

-      /* If we have allocated the row_buf, this means we have already started

-       * with the image and we should have allocated all of the filter buffers

-       * that have been selected.  If prev_row isn't already allocated, then

-       * it is too late to start using the filters that need it, since we

-       * will be missing the data in the previous row.  If an application

-       * wants to start and stop using particular filters during compression,

-       * it should start out with all of the filters, and then add and

-       * remove them after the start of compression.

-       */

-      if (png_ptr->row_buf != NULL)

-      {

-#ifdef PNG_WRITE_FILTER_SUPPORTED

-         if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)

-         {

-            png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,

-                (png_ptr->rowbytes + 1));

-            png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;

-         }

-

-         if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)

-         {

-            if (png_ptr->prev_row == NULL)

-            {

-               png_warning(png_ptr, "Can't add Up filter after starting");

-               png_ptr->do_filter = (png_byte)(png_ptr->do_filter &

-                   ~PNG_FILTER_UP);

-            }

-

-            else

-            {

-               png_ptr->up_row = (png_bytep)png_malloc(png_ptr,

-                   (png_ptr->rowbytes + 1));

-               png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;

-            }

-         }

-

-         if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)

-         {

-            if (png_ptr->prev_row == NULL)

-            {

-               png_warning(png_ptr, "Can't add Average filter after starting");

-               png_ptr->do_filter = (png_byte)(png_ptr->do_filter &

-                   ~PNG_FILTER_AVG);

-            }

-

-            else

-            {

-               png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,

-                   (png_ptr->rowbytes + 1));

-               png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;

-            }

-         }

-

-         if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&

-             png_ptr->paeth_row == NULL)

-         {

-            if (png_ptr->prev_row == NULL)

-            {

-               png_warning(png_ptr, "Can't add Paeth filter after starting");

-               png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);

-            }

-

-            else

-            {

-               png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,

-                   (png_ptr->rowbytes + 1));

-               png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;

-            }

-         }

-

-         if (png_ptr->do_filter == PNG_NO_FILTERS)

-#endif /* PNG_WRITE_FILTER_SUPPORTED */

-            png_ptr->do_filter = PNG_FILTER_NONE;

-      }

-   }

-   else

-      png_error(png_ptr, "Unknown custom filter method");

-}

-

-/* This allows us to influence the way in which libpng chooses the "best"

- * filter for the current scanline.  While the "minimum-sum-of-absolute-

- * differences metric is relatively fast and effective, there is some

- * question as to whether it can be improved upon by trying to keep the

- * filtered data going to zlib more consistent, hopefully resulting in

- * better compression.

- */

-#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED      /* GRR 970116 */

-/* Convenience reset API. */

-static void

-png_reset_filter_heuristics(png_structp png_ptr)

-{

-   /* Clear out any old values in the 'weights' - this must be done because if

-    * the app calls set_filter_heuristics multiple times with different

-    * 'num_weights' values we would otherwise potentially have wrong sized

-    * arrays.

-    */

-   png_ptr->num_prev_filters = 0;

-   png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;

-   if (png_ptr->prev_filters != NULL)

-   {

-      png_bytep old = png_ptr->prev_filters;

-      png_ptr->prev_filters = NULL;

-      png_free(png_ptr, old);

-   }

-   if (png_ptr->filter_weights != NULL)

-   {

-      png_uint_16p old = png_ptr->filter_weights;

-      png_ptr->filter_weights = NULL;

-      png_free(png_ptr, old);

-   }

-

-   if (png_ptr->inv_filter_weights != NULL)

-   {

-      png_uint_16p old = png_ptr->inv_filter_weights;

-      png_ptr->inv_filter_weights = NULL;

-      png_free(png_ptr, old);

-   }

-

-   /* Leave the filter_costs - this array is fixed size. */

-}

-

-static int

-png_init_filter_heuristics(png_structp png_ptr, int heuristic_method,

-   int num_weights)

-{

-   if (png_ptr == NULL)

-      return 0;

-

-   /* Clear out the arrays */

-   png_reset_filter_heuristics(png_ptr);

-

-   /* Check arguments; the 'reset' function makes the correct settings for the

-    * unweighted case, but we must handle the weight case by initializing the

-    * arrays for the caller.

-    */

-   if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)

-   {

-      int i;

-

-      if (num_weights > 0)

-      {

-         png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,

-             (png_uint_32)(png_sizeof(png_byte) * num_weights));

-

-         /* To make sure that the weighting starts out fairly */

-         for (i = 0; i < num_weights; i++)

-         {

-            png_ptr->prev_filters[i] = 255;

-         }

-

-         png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,

-             (png_uint_32)(png_sizeof(png_uint_16) * num_weights));

-

-         png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,

-             (png_uint_32)(png_sizeof(png_uint_16) * num_weights));

-

-         for (i = 0; i < num_weights; i++)

-         {

-            png_ptr->inv_filter_weights[i] =

-            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;

-         }

-

-         /* Safe to set this now */

-         png_ptr->num_prev_filters = (png_byte)num_weights;

-      }

-

-      /* If, in the future, there are other filter methods, this would

-       * need to be based on png_ptr->filter.

-       */

-      if (png_ptr->filter_costs == NULL)

-      {

-         png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,

-             (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));

-

-         png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,

-             (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));

-      }

-

-      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)

-      {

-         png_ptr->inv_filter_costs[i] =

-         png_ptr->filter_costs[i] = PNG_COST_FACTOR;

-      }

-

-      /* All the arrays are inited, safe to set this: */

-      png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_WEIGHTED;

-

-      /* Return the 'ok' code. */

-      return 1;

-   }

-   else if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT ||

-      heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)

-   {

-      return 1;

-   }

-   else

-   {

-      png_warning(png_ptr, "Unknown filter heuristic method");

-      return 0;

-   }

-}

-

-/* Provide floating and fixed point APIs */

-#ifdef PNG_FLOATING_POINT_SUPPORTED

-void PNGAPI

-png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,

-    int num_weights, png_const_doublep filter_weights,

-    png_const_doublep filter_costs)

-{

-   png_debug(1, "in png_set_filter_heuristics");

-

-   /* The internal API allocates all the arrays and ensures that the elements of

-    * those arrays are set to the default value.

-    */

-   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))

-      return;

-

-   /* If using the weighted method copy in the weights. */

-   if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)

-   {

-      int i;

-      for (i = 0; i < num_weights; i++)

-      {

-         if (filter_weights[i] <= 0.0)

-         {

-            png_ptr->inv_filter_weights[i] =

-            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;

-         }

-

-         else

-         {

-            png_ptr->inv_filter_weights[i] =

-                (png_uint_16)(PNG_WEIGHT_FACTOR*filter_weights[i]+.5);

-

-            png_ptr->filter_weights[i] =

-                (png_uint_16)(PNG_WEIGHT_FACTOR/filter_weights[i]+.5);

-         }

-      }

-

-      /* Here is where we set the relative costs of the different filters.  We

-       * should take the desired compression level into account when setting

-       * the costs, so that Paeth, for instance, has a high relative cost at low

-       * compression levels, while it has a lower relative cost at higher

-       * compression settings.  The filter types are in order of increasing

-       * relative cost, so it would be possible to do this with an algorithm.

-       */

-      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) if (filter_costs[i] >= 1.0)

-      {

-         png_ptr->inv_filter_costs[i] =

-             (png_uint_16)(PNG_COST_FACTOR / filter_costs[i] + .5);

-

-         png_ptr->filter_costs[i] =

-             (png_uint_16)(PNG_COST_FACTOR * filter_costs[i] + .5);

-      }

-   }

-}

-#endif /* FLOATING_POINT */

-

-#ifdef PNG_FIXED_POINT_SUPPORTED

-void PNGAPI

-png_set_filter_heuristics_fixed(png_structp png_ptr, int heuristic_method,

-    int num_weights, png_const_fixed_point_p filter_weights,

-    png_const_fixed_point_p filter_costs)

-{

-   png_debug(1, "in png_set_filter_heuristics_fixed");

-

-   /* The internal API allocates all the arrays and ensures that the elements of

-    * those arrays are set to the default value.

-    */

-   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))

-      return;

-

-   /* If using the weighted method copy in the weights. */

-   if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)

-   {

-      int i;

-      for (i = 0; i < num_weights; i++)

-      {

-         if (filter_weights[i] <= 0)

-         {

-            png_ptr->inv_filter_weights[i] =

-            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;

-         }

-

-         else

-         {

-            png_ptr->inv_filter_weights[i] = (png_uint_16)

-               ((PNG_WEIGHT_FACTOR*filter_weights[i]+PNG_FP_HALF)/PNG_FP_1);

-

-            png_ptr->filter_weights[i] = (png_uint_16)((PNG_WEIGHT_FACTOR*

-               PNG_FP_1+(filter_weights[i]/2))/filter_weights[i]);

-         }

-      }

-

-      /* Here is where we set the relative costs of the different filters.  We

-       * should take the desired compression level into account when setting

-       * the costs, so that Paeth, for instance, has a high relative cost at low

-       * compression levels, while it has a lower relative cost at higher

-       * compression settings.  The filter types are in order of increasing

-       * relative cost, so it would be possible to do this with an algorithm.

-       */

-      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)

-         if (filter_costs[i] >= PNG_FP_1)

-      {

-         png_uint_32 tmp;

-

-         /* Use a 32 bit unsigned temporary here because otherwise the

-          * intermediate value will be a 32 bit *signed* integer (ANSI rules)

-          * and this will get the wrong answer on division.

-          */

-         tmp = PNG_COST_FACTOR*PNG_FP_1 + (filter_costs[i]/2);

-         tmp /= filter_costs[i];

-

-         png_ptr->inv_filter_costs[i] = (png_uint_16)tmp;

-

-         tmp = PNG_COST_FACTOR * filter_costs[i] + PNG_FP_HALF;

-         tmp /= PNG_FP_1;

-

-         png_ptr->filter_costs[i] = (png_uint_16)tmp;

-      }

-   }

-}

-#endif /* FIXED_POINT */

-#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */

-

-void PNGAPI

-png_set_compression_level(png_structp png_ptr, int level)

-{

-   png_debug(1, "in png_set_compression_level");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;

-   png_ptr->zlib_level = level;

-}

-

-void PNGAPI

-png_set_compression_mem_level(png_structp png_ptr, int mem_level)

-{

-   png_debug(1, "in png_set_compression_mem_level");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;

-   png_ptr->zlib_mem_level = mem_level;

-}

-

-void PNGAPI

-png_set_compression_strategy(png_structp png_ptr, int strategy)

-{

-   png_debug(1, "in png_set_compression_strategy");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;

-   png_ptr->zlib_strategy = strategy;

-}

-

-/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a

- * smaller value of window_bits if it can do so safely.

- */

-void PNGAPI

-png_set_compression_window_bits(png_structp png_ptr, int window_bits)

-{

-   if (png_ptr == NULL)

-      return;

-

-   if (window_bits > 15)

-      png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");

-

-   else if (window_bits < 8)

-      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");

-

-#ifndef WBITS_8_OK

-   /* Avoid libpng bug with 256-byte windows */

-   if (window_bits == 8)

-      {

-        png_warning(png_ptr, "Compression window is being reset to 512");

-        window_bits = 9;

-      }

-

-#endif

-   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;

-   png_ptr->zlib_window_bits = window_bits;

-}

-

-void PNGAPI

-png_set_compression_method(png_structp png_ptr, int method)

-{

-   png_debug(1, "in png_set_compression_method");

-

-   if (png_ptr == NULL)

-      return;

-

-   if (method != 8)

-      png_warning(png_ptr, "Only compression method 8 is supported by PNG");

-

-   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;

-   png_ptr->zlib_method = method;

-}

-

-/* The following were added to libpng-1.5.4 */

-#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED

-void PNGAPI

-png_set_text_compression_level(png_structp png_ptr, int level)

-{

-   png_debug(1, "in png_set_text_compression_level");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_LEVEL;

-   png_ptr->zlib_text_level = level;

-}

-

-void PNGAPI

-png_set_text_compression_mem_level(png_structp png_ptr, int mem_level)

-{

-   png_debug(1, "in png_set_text_compression_mem_level");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL;

-   png_ptr->zlib_text_mem_level = mem_level;

-}

-

-void PNGAPI

-png_set_text_compression_strategy(png_structp png_ptr, int strategy)

-{

-   png_debug(1, "in png_set_text_compression_strategy");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_STRATEGY;

-   png_ptr->zlib_text_strategy = strategy;

-}

-

-/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a

- * smaller value of window_bits if it can do so safely.

- */

-void PNGAPI

-png_set_text_compression_window_bits(png_structp png_ptr, int window_bits)

-{

-   if (png_ptr == NULL)

-      return;

-

-   if (window_bits > 15)

-      png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");

-

-   else if (window_bits < 8)

-      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");

-

-#ifndef WBITS_8_OK

-   /* Avoid libpng bug with 256-byte windows */

-   if (window_bits == 8)

-      {

-        png_warning(png_ptr, "Text compression window is being reset to 512");

-        window_bits = 9;

-      }

-

-#endif

-   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS;

-   png_ptr->zlib_text_window_bits = window_bits;

-}

-

-void PNGAPI

-png_set_text_compression_method(png_structp png_ptr, int method)

-{

-   png_debug(1, "in png_set_text_compression_method");

-

-   if (png_ptr == NULL)

-      return;

-

-   if (method != 8)

-      png_warning(png_ptr, "Only compression method 8 is supported by PNG");

-

-   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_METHOD;

-   png_ptr->zlib_text_method = method;

-}

-#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */

-/* end of API added to libpng-1.5.4 */

-

-void PNGAPI

-png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)

-{

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->write_row_fn = write_row_fn;

-}

-

-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED

-void PNGAPI

-png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr

-    write_user_transform_fn)

-{

-   png_debug(1, "in png_set_write_user_transform_fn");

-

-   if (png_ptr == NULL)

-      return;

-

-   png_ptr->transformations |= PNG_USER_TRANSFORM;

-   png_ptr->write_user_transform_fn = write_user_transform_fn;

-}

-#endif

-

-

-#ifdef PNG_INFO_IMAGE_SUPPORTED

-void PNGAPI

-png_write_png(png_structp png_ptr, png_infop info_ptr,

-    int transforms, voidp params)

-{

-   if (png_ptr == NULL || info_ptr == NULL)

-      return;

-

-   /* Write the file header information. */

-   png_write_info(png_ptr, info_ptr);

-

-   /* ------ these transformations don't touch the info structure ------- */

-

-#ifdef PNG_WRITE_INVERT_SUPPORTED

-   /* Invert monochrome pixels */

-   if (transforms & PNG_TRANSFORM_INVERT_MONO)

-      png_set_invert_mono(png_ptr);

-#endif

-

-#ifdef PNG_WRITE_SHIFT_SUPPORTED

-   /* Shift the pixels up to a legal bit depth and fill in

-    * as appropriate to correctly scale the image.

-    */

-   if ((transforms & PNG_TRANSFORM_SHIFT)

-       && (info_ptr->valid & PNG_INFO_sBIT))

-      png_set_shift(png_ptr, &info_ptr->sig_bit);

-#endif

-

-#ifdef PNG_WRITE_PACK_SUPPORTED

-   /* Pack pixels into bytes */

-   if (transforms & PNG_TRANSFORM_PACKING)

-       png_set_packing(png_ptr);

-#endif

-

-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED

-   /* Swap location of alpha bytes from ARGB to RGBA */

-   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)

-      png_set_swap_alpha(png_ptr);

-#endif

-

-#ifdef PNG_WRITE_FILLER_SUPPORTED

-   /* Pack XRGB/RGBX/ARGB/RGBA into RGB (4 channels -> 3 channels) */

-   if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER)

-      png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);

-

-   else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)

-      png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);

-#endif

-

-#ifdef PNG_WRITE_BGR_SUPPORTED

-   /* Flip BGR pixels to RGB */

-   if (transforms & PNG_TRANSFORM_BGR)

-      png_set_bgr(png_ptr);

-#endif

-

-#ifdef PNG_WRITE_SWAP_SUPPORTED

-   /* Swap bytes of 16-bit files to most significant byte first */

-   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)

-      png_set_swap(png_ptr);

-#endif

-

-#ifdef PNG_WRITE_PACKSWAP_SUPPORTED

-   /* Swap bits of 1, 2, 4 bit packed pixel formats */

-   if (transforms & PNG_TRANSFORM_PACKSWAP)

-      png_set_packswap(png_ptr);

-#endif

-

-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED

-   /* Invert the alpha channel from opacity to transparency */

-   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)

-      png_set_invert_alpha(png_ptr);

-#endif

-

-   /* ----------------------- end of transformations ------------------- */

-

-   /* Write the bits */

-   if (info_ptr->valid & PNG_INFO_IDAT)

-       png_write_image(png_ptr, info_ptr->row_pointers);

-

-   /* It is REQUIRED to call this to finish writing the rest of the file */

-   png_write_end(png_ptr, info_ptr);

-

-   PNG_UNUSED(transforms)   /* Quiet compiler warnings */

-   PNG_UNUSED(params)

-}

-#endif

-#endif /* PNG_WRITE_SUPPORTED */

+
+/* pngwrite.c - general routines to write a PNG file
+ *
+ * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Copyright (c) 1998-2011 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.)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include "pngpriv.h"
+
+#ifdef PNG_WRITE_SUPPORTED
+
+/* Writes all the PNG information.  This is the suggested way to use the
+ * library.  If you have a new chunk to add, make a function to write it,
+ * and put it in the correct location here.  If you want the chunk written
+ * after the image data, put it in png_write_end().  I strongly encourage
+ * you to supply a PNG_INFO_ flag, and check info_ptr->valid before writing
+ * the chunk, as that will keep the code from breaking if you want to just
+ * write a plain PNG file.  If you have long comments, I suggest writing
+ * them in png_write_end(), and compressing them.
+ */
+void PNGAPI
+png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_write_info_before_PLTE");
+
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+   {
+   /* Write PNG signature */
+   png_write_sig(png_ptr);
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+   if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \
+       (png_ptr->mng_features_permitted))
+   {
+      png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
+      png_ptr->mng_features_permitted = 0;
+   }
+#endif
+
+   /* Write IHDR information. */
+   png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
+       info_ptr->bit_depth, info_ptr->color_type, info_ptr->compression_type,
+       info_ptr->filter_type,
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+       info_ptr->interlace_type);
+#else
+       0);
+#endif
+   /* The rest of these check to see if the valid field has the appropriate
+    * flag set, and if it does, writes the chunk.
+    */
+#ifdef PNG_WRITE_gAMA_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_gAMA)
+      png_write_gAMA_fixed(png_ptr, info_ptr->gamma);
+#endif
+#ifdef PNG_WRITE_sRGB_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_sRGB)
+      png_write_sRGB(png_ptr, (int)info_ptr->srgb_intent);
+#endif
+
+#ifdef PNG_WRITE_iCCP_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_iCCP)
+      png_write_iCCP(png_ptr, info_ptr->iccp_name, PNG_COMPRESSION_TYPE_BASE,
+          (png_charp)info_ptr->iccp_profile, (int)info_ptr->iccp_proflen);
+#endif
+#ifdef PNG_WRITE_sBIT_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_sBIT)
+      png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
+#endif
+#ifdef PNG_WRITE_cHRM_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_cHRM)
+      png_write_cHRM_fixed(png_ptr,
+          info_ptr->x_white, info_ptr->y_white,
+          info_ptr->x_red, info_ptr->y_red,
+          info_ptr->x_green, info_ptr->y_green,
+          info_ptr->x_blue, info_ptr->y_blue);
+#endif
+
+#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+   if (info_ptr->unknown_chunks_num)
+   {
+      png_unknown_chunk *up;
+
+      png_debug(5, "writing extra chunks");
+
+      for (up = info_ptr->unknown_chunks;
+           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+           up++)
+      {
+         int keep = png_handle_as_unknown(png_ptr, up->name);
+
+         if (keep != PNG_HANDLE_CHUNK_NEVER &&
+             up->location &&
+             !(up->location & PNG_HAVE_PLTE) &&
+             !(up->location & PNG_HAVE_IDAT) &&
+             !(up->location & PNG_AFTER_IDAT) &&
+             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+         {
+            if (up->size == 0)
+               png_warning(png_ptr, "Writing zero-length unknown chunk");
+
+            png_write_chunk(png_ptr, up->name, up->data, up->size);
+         }
+      }
+   }
+#endif
+      png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
+   }
+}
+
+void PNGAPI
+png_write_info(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
+   int i;
+#endif
+
+   png_debug(1, "in png_write_info");
+
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_write_info_before_PLTE(png_ptr, info_ptr);
+
+   if (info_ptr->valid & PNG_INFO_PLTE)
+      png_write_PLTE(png_ptr, info_ptr->palette,
+          (png_uint_32)info_ptr->num_palette);
+
+   else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      png_error(png_ptr, "Valid palette required for paletted images");
+
+#ifdef PNG_WRITE_tRNS_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_tRNS)
+   {
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
+      /* Invert the alpha channel (in tRNS) */
+      if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
+          info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+         int j;
+         for (j = 0; j<(int)info_ptr->num_trans; j++)
+            info_ptr->trans_alpha[j] =
+               (png_byte)(255 - info_ptr->trans_alpha[j]);
+      }
+#endif
+      png_write_tRNS(png_ptr, info_ptr->trans_alpha, &(info_ptr->trans_color),
+          info_ptr->num_trans, info_ptr->color_type);
+   }
+#endif
+#ifdef PNG_WRITE_bKGD_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_bKGD)
+      png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
+#endif
+
+#ifdef PNG_WRITE_hIST_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_hIST)
+      png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
+#endif
+
+#ifdef PNG_WRITE_oFFs_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_oFFs)
+      png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
+          info_ptr->offset_unit_type);
+#endif
+
+#ifdef PNG_WRITE_pCAL_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_pCAL)
+      png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
+          info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
+          info_ptr->pcal_units, info_ptr->pcal_params);
+#endif
+
+#ifdef PNG_WRITE_sCAL_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_sCAL)
+      png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
+          info_ptr->scal_s_width, info_ptr->scal_s_height);
+#endif /* sCAL */
+
+#ifdef PNG_WRITE_pHYs_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_pHYs)
+      png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
+          info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
+#endif /* pHYs */
+
+#ifdef PNG_WRITE_tIME_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_tIME)
+   {
+      png_write_tIME(png_ptr, &(info_ptr->mod_time));
+      png_ptr->mode |= PNG_WROTE_tIME;
+   }
+#endif /* tIME */
+
+#ifdef PNG_WRITE_sPLT_SUPPORTED
+   if (info_ptr->valid & PNG_INFO_sPLT)
+      for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
+         png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
+#endif /* sPLT */
+
+#ifdef PNG_WRITE_TEXT_SUPPORTED
+   /* Check to see if we need to write text chunks */
+   for (i = 0; i < info_ptr->num_text; i++)
+   {
+      png_debug2(2, "Writing header text chunk %d, type %d", i,
+          info_ptr->text[i].compression);
+      /* An internationalized chunk? */
+      if (info_ptr->text[i].compression > 0)
+      {
+#ifdef PNG_WRITE_iTXt_SUPPORTED
+         /* Write international chunk */
+         png_write_iTXt(png_ptr,
+             info_ptr->text[i].compression,
+             info_ptr->text[i].key,
+             info_ptr->text[i].lang,
+             info_ptr->text[i].lang_key,
+             info_ptr->text[i].text);
+#else
+          png_warning(png_ptr, "Unable to write international text");
+#endif
+          /* Mark this chunk as written */
+          info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+      }
+
+      /* If we want a compressed text chunk */
+      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
+      {
+#ifdef PNG_WRITE_zTXt_SUPPORTED
+         /* Write compressed chunk */
+         png_write_zTXt(png_ptr, info_ptr->text[i].key,
+             info_ptr->text[i].text, 0,
+             info_ptr->text[i].compression);
+#else
+         png_warning(png_ptr, "Unable to write compressed text");
+#endif
+         /* Mark this chunk as written */
+         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
+      }
+
+      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+      {
+#ifdef PNG_WRITE_tEXt_SUPPORTED
+         /* Write uncompressed chunk */
+         png_write_tEXt(png_ptr, info_ptr->text[i].key,
+             info_ptr->text[i].text,
+             0);
+         /* Mark this chunk as written */
+         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+#else
+         /* Can't get here */
+         png_warning(png_ptr, "Unable to write uncompressed text");
+#endif
+      }
+   }
+#endif /* tEXt */
+
+#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+   if (info_ptr->unknown_chunks_num)
+   {
+      png_unknown_chunk *up;
+
+      png_debug(5, "writing extra chunks");
+
+      for (up = info_ptr->unknown_chunks;
+           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+           up++)
+      {
+         int keep = png_handle_as_unknown(png_ptr, up->name);
+         if (keep != PNG_HANDLE_CHUNK_NEVER &&
+             up->location &&
+             (up->location & PNG_HAVE_PLTE) &&
+             !(up->location & PNG_HAVE_IDAT) &&
+             !(up->location & PNG_AFTER_IDAT) &&
+             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+         {
+            png_write_chunk(png_ptr, up->name, up->data, up->size);
+         }
+      }
+   }
+#endif
+}
+
+/* Writes the end of the PNG file.  If you don't want to write comments or
+ * time information, you can pass NULL for info.  If you already wrote these
+ * in png_write_info(), do not write them again here.  If you have long
+ * comments, I suggest writing them here, and compressing them.
+ */
+void PNGAPI
+png_write_end(png_structp png_ptr, png_infop info_ptr)
+{
+   png_debug(1, "in png_write_end");
+
+   if (png_ptr == NULL)
+      return;
+
+   if (!(png_ptr->mode & PNG_HAVE_IDAT))
+      png_error(png_ptr, "No IDATs written into file");
+
+   /* See if user wants us to write information chunks */
+   if (info_ptr != NULL)
+   {
+#ifdef PNG_WRITE_TEXT_SUPPORTED
+      int i; /* local index variable */
+#endif
+#ifdef PNG_WRITE_tIME_SUPPORTED
+      /* Check to see if user has supplied a time chunk */
+      if ((info_ptr->valid & PNG_INFO_tIME) &&
+          !(png_ptr->mode & PNG_WROTE_tIME))
+         png_write_tIME(png_ptr, &(info_ptr->mod_time));
+
+#endif
+#ifdef PNG_WRITE_TEXT_SUPPORTED
+      /* Loop through comment chunks */
+      for (i = 0; i < info_ptr->num_text; i++)
+      {
+         png_debug2(2, "Writing trailer text chunk %d, type %d", i,
+            info_ptr->text[i].compression);
+         /* An internationalized chunk? */
+         if (info_ptr->text[i].compression > 0)
+         {
+#ifdef PNG_WRITE_iTXt_SUPPORTED
+            /* Write international chunk */
+            png_write_iTXt(png_ptr,
+                info_ptr->text[i].compression,
+                info_ptr->text[i].key,
+                info_ptr->text[i].lang,
+                info_ptr->text[i].lang_key,
+                info_ptr->text[i].text);
+#else
+            png_warning(png_ptr, "Unable to write international text");
+#endif
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+         }
+
+         else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
+         {
+#ifdef PNG_WRITE_zTXt_SUPPORTED
+            /* Write compressed chunk */
+            png_write_zTXt(png_ptr, info_ptr->text[i].key,
+                info_ptr->text[i].text, 0,
+                info_ptr->text[i].compression);
+#else
+            png_warning(png_ptr, "Unable to write compressed text");
+#endif
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
+         }
+
+         else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+         {
+#ifdef PNG_WRITE_tEXt_SUPPORTED
+            /* Write uncompressed chunk */
+            png_write_tEXt(png_ptr, info_ptr->text[i].key,
+                info_ptr->text[i].text, 0);
+#else
+            png_warning(png_ptr, "Unable to write uncompressed text");
+#endif
+
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+         }
+      }
+#endif
+#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+   if (info_ptr->unknown_chunks_num)
+   {
+      png_unknown_chunk *up;
+
+      png_debug(5, "writing extra chunks");
+
+      for (up = info_ptr->unknown_chunks;
+           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
+           up++)
+      {
+         int keep = png_handle_as_unknown(png_ptr, up->name);
+         if (keep != PNG_HANDLE_CHUNK_NEVER &&
+             up->location &&
+             (up->location & PNG_AFTER_IDAT) &&
+             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
+             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
+         {
+            png_write_chunk(png_ptr, up->name, up->data, up->size);
+         }
+      }
+   }
+#endif
+   }
+
+   png_ptr->mode |= PNG_AFTER_IDAT;
+
+   /* Write end of PNG file */
+   png_write_IEND(png_ptr);
+   /* This flush, added in libpng-1.0.8, removed from libpng-1.0.9beta03,
+    * and restored again in libpng-1.2.30, may cause some applications that
+    * do not set png_ptr->output_flush_fn to crash.  If your application
+    * experiences a problem, please try building libpng with
+    * PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED defined, and report the event to
+    * png-mng-implement at lists.sf.net .
+    */
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+#  ifdef PNG_WRITE_FLUSH_AFTER_IEND_SUPPORTED
+   png_flush(png_ptr);
+#  endif
+#endif
+}
+
+#ifdef PNG_CONVERT_tIME_SUPPORTED
+/* "tm" structure is not supported on WindowsCE */
+void PNGAPI
+png_convert_from_struct_tm(png_timep ptime, PNG_CONST struct tm FAR * ttime)
+{
+   png_debug(1, "in png_convert_from_struct_tm");
+
+   ptime->year = (png_uint_16)(1900 + ttime->tm_year);
+   ptime->month = (png_byte)(ttime->tm_mon + 1);
+   ptime->day = (png_byte)ttime->tm_mday;
+   ptime->hour = (png_byte)ttime->tm_hour;
+   ptime->minute = (png_byte)ttime->tm_min;
+   ptime->second = (png_byte)ttime->tm_sec;
+}
+
+void PNGAPI
+png_convert_from_time_t(png_timep ptime, time_t ttime)
+{
+   struct tm *tbuf;
+
+   png_debug(1, "in png_convert_from_time_t");
+
+   tbuf = gmtime(&ttime);
+   png_convert_from_struct_tm(ptime, tbuf);
+}
+#endif
+
+/* Initialize png_ptr structure, and allocate any memory needed */
+PNG_FUNCTION(png_structp,PNGAPI
+png_create_write_struct,(png_const_charp user_png_ver, png_voidp error_ptr,
+    png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED)
+{
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_write_struct_2(user_png_ver, error_ptr, error_fn,
+       warn_fn, NULL, NULL, NULL));
+}
+
+/* Alternate initialize png_ptr structure, and allocate any memory needed */
+static void png_reset_filter_heuristics(png_structp png_ptr); /* forward decl */
+
+PNG_FUNCTION(png_structp,PNGAPI
+png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
+    png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
+    png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   volatile int png_cleanup_needed = 0;
+#ifdef PNG_SETJMP_SUPPORTED
+   volatile
+#endif
+   png_structp png_ptr;
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+   jmp_buf tmp_jmpbuf;
+#endif
+#endif
+
+   png_debug(1, "in png_create_write_struct");
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
+       (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
+#else
+   png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+#endif /* PNG_USER_MEM_SUPPORTED */
+   if (png_ptr == NULL)
+      return (NULL);
+
+   /* Added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+   png_ptr->user_width_max = PNG_USER_WIDTH_MAX;
+   png_ptr->user_height_max = PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+/* Applications that neglect to set up their own setjmp() and then
+ * encounter a png_error() will longjmp here.  Since the jmpbuf is
+ * then meaningless we abort instead of returning.
+ */
+#ifdef USE_FAR_KEYWORD
+   if (setjmp(tmp_jmpbuf))
+#else
+   if (setjmp(png_jmpbuf(png_ptr))) /* sets longjmp to match setjmp */
+#endif
+#ifdef USE_FAR_KEYWORD
+   png_memcpy(png_jmpbuf(png_ptr), tmp_jmpbuf, png_sizeof(jmp_buf));
+#endif
+      PNG_ABORT();
+#endif
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
+
+   if (!png_user_version_check(png_ptr, user_png_ver))
+      png_cleanup_needed = 1;
+
+   /* Initialize zbuf - compression buffer */
+   png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+
+   if (!png_cleanup_needed)
+   {
+      png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr,
+          png_ptr->zbuf_size);
+      if (png_ptr->zbuf == NULL)
+         png_cleanup_needed = 1;
+   }
+
+   if (png_cleanup_needed)
+   {
+       /* Clean up PNG structure and deallocate any memory. */
+       png_free(png_ptr, png_ptr->zbuf);
+       png_ptr->zbuf = NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+       png_destroy_struct_2((png_voidp)png_ptr,
+           (png_free_ptr)free_fn, (png_voidp)mem_ptr);
+#else
+       png_destroy_struct((png_voidp)png_ptr);
+#endif
+       return (NULL);
+   }
+
+   png_set_write_fn(png_ptr, NULL, NULL, NULL);
+
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+   png_reset_filter_heuristics(png_ptr);
+#endif
+
+   return (png_ptr);
+}
+
+
+/* Write a few rows of image data.  If the image is interlaced,
+ * either you will have to write the 7 sub images, or, if you
+ * have called png_set_interlace_handling(), you will have to
+ * "write" the image seven times.
+ */
+void PNGAPI
+png_write_rows(png_structp png_ptr, png_bytepp row,
+    png_uint_32 num_rows)
+{
+   png_uint_32 i; /* row counter */
+   png_bytepp rp; /* row pointer */
+
+   png_debug(1, "in png_write_rows");
+
+   if (png_ptr == NULL)
+      return;
+
+   /* Loop through the rows */
+   for (i = 0, rp = row; i < num_rows; i++, rp++)
+   {
+      png_write_row(png_ptr, *rp);
+   }
+}
+
+/* Write the image.  You only need to call this function once, even
+ * if you are writing an interlaced image.
+ */
+void PNGAPI
+png_write_image(png_structp png_ptr, png_bytepp image)
+{
+   png_uint_32 i; /* row index */
+   int pass, num_pass; /* pass variables */
+   png_bytepp rp; /* points to current row */
+
+   if (png_ptr == NULL)
+      return;
+
+   png_debug(1, "in png_write_image");
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+   /* Initialize interlace handling.  If image is not interlaced,
+    * this will set pass to 1
+    */
+   num_pass = png_set_interlace_handling(png_ptr);
+#else
+   num_pass = 1;
+#endif
+   /* Loop through passes */
+   for (pass = 0; pass < num_pass; pass++)
+   {
+      /* Loop through image */
+      for (i = 0, rp = image; i < png_ptr->height; i++, rp++)
+      {
+         png_write_row(png_ptr, *rp);
+      }
+   }
+}
+
+/* Called by user to write a row of image data */
+void PNGAPI
+png_write_row(png_structp png_ptr, png_const_bytep row)
+{
+   /* 1.5.6: moved from png_struct to be a local structure: */
+   png_row_info row_info;
+
+   if (png_ptr == NULL)
+      return;
+
+   png_debug2(1, "in png_write_row (row %u, pass %d)",
+      png_ptr->row_number, png_ptr->pass);
+
+   /* Initialize transformations and other stuff if first time */
+   if (png_ptr->row_number == 0 && png_ptr->pass == 0)
+   {
+      /* Make sure we wrote the header info */
+      if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+         png_error(png_ptr,
+             "png_write_info was never called before png_write_row");
+
+      /* Check for transforms that have been set but were defined out */
+#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
+      if (png_ptr->transformations & PNG_INVERT_MONO)
+         png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined");
+#endif
+
+#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
+      if (png_ptr->transformations & PNG_FILLER)
+         png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined");
+#endif
+#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
+    defined(PNG_READ_PACKSWAP_SUPPORTED)
+      if (png_ptr->transformations & PNG_PACKSWAP)
+         png_warning(png_ptr,
+             "PNG_WRITE_PACKSWAP_SUPPORTED is not defined");
+#endif
+
+#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
+      if (png_ptr->transformations & PNG_PACK)
+         png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined");
+#endif
+
+#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
+      if (png_ptr->transformations & PNG_SHIFT)
+         png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined");
+#endif
+
+#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
+      if (png_ptr->transformations & PNG_BGR)
+         png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined");
+#endif
+
+#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
+      if (png_ptr->transformations & PNG_SWAP_BYTES)
+         png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined");
+#endif
+
+      png_write_start_row(png_ptr);
+   }
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+   /* If interlaced and not interested in row, return */
+   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   {
+      switch (png_ptr->pass)
+      {
+         case 0:
+            if (png_ptr->row_number & 0x07)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         case 1:
+            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         case 2:
+            if ((png_ptr->row_number & 0x07) != 4)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         case 3:
+            if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         case 4:
+            if ((png_ptr->row_number & 0x03) != 2)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         case 5:
+            if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         case 6:
+            if (!(png_ptr->row_number & 0x01))
+            {
+               png_write_finish_row(png_ptr);
+               return;
+            }
+            break;
+
+         default: /* error: ignore it */
+            break;
+      }
+   }
+#endif
+
+   /* Set up row info for transformations */
+   row_info.color_type = png_ptr->color_type;
+   row_info.width = png_ptr->usr_width;
+   row_info.channels = png_ptr->usr_channels;
+   row_info.bit_depth = png_ptr->usr_bit_depth;
+   row_info.pixel_depth = (png_byte)(row_info.bit_depth * row_info.channels);
+   row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width);
+
+   png_debug1(3, "row_info->color_type = %d", row_info.color_type);
+   png_debug1(3, "row_info->width = %u", row_info.width);
+   png_debug1(3, "row_info->channels = %d", row_info.channels);
+   png_debug1(3, "row_info->bit_depth = %d", row_info.bit_depth);
+   png_debug1(3, "row_info->pixel_depth = %d", row_info.pixel_depth);
+   png_debug1(3, "row_info->rowbytes = %lu", (unsigned long)row_info.rowbytes);
+
+   /* Copy user's row into buffer, leaving room for filter byte. */
+   png_memcpy(png_ptr->row_buf + 1, row, row_info.rowbytes);
+
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+   /* Handle interlacing */
+   if (png_ptr->interlaced && png_ptr->pass < 6 &&
+       (png_ptr->transformations & PNG_INTERLACE))
+   {
+      png_do_write_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass);
+      /* This should always get caught above, but still ... */
+      if (!(row_info.width))
+      {
+         png_write_finish_row(png_ptr);
+         return;
+      }
+   }
+#endif
+
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+   /* Handle other transformations */
+   if (png_ptr->transformations)
+      png_do_write_transformations(png_ptr, &row_info);
+#endif
+
+   /* At this point the row_info pixel depth must match the 'transformed' depth,
+    * which is also the output depth.
+    */
+   if (row_info.pixel_depth != png_ptr->pixel_depth ||
+      row_info.pixel_depth != png_ptr->transformed_pixel_depth)
+      png_error(png_ptr, "internal write transform logic error");
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+   /* Write filter_method 64 (intrapixel differencing) only if
+    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
+    * 2. Libpng did not write a PNG signature (this filter_method is only
+    *    used in PNG datastreams that are embedded in MNG datastreams) and
+    * 3. The application called png_permit_mng_features with a mask that
+    *    included PNG_FLAG_MNG_FILTER_64 and
+    * 4. The filter_method is 64 and
+    * 5. The color_type is RGB or RGBA
+    */
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+       (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
+   {
+      /* Intrapixel differencing */
+      png_do_write_intrapixel(&row_info, png_ptr->row_buf + 1);
+   }
+#endif
+
+   /* Find a filter if necessary, filter the row and write it out. */
+   png_write_find_filter(png_ptr, &row_info);
+
+   if (png_ptr->write_row_fn != NULL)
+      (*(png_ptr->write_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
+}
+
+#ifdef PNG_WRITE_FLUSH_SUPPORTED
+/* Set the automatic flush interval or 0 to turn flushing off */
+void PNGAPI
+png_set_flush(png_structp png_ptr, int nrows)
+{
+   png_debug(1, "in png_set_flush");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flush_dist = (nrows < 0 ? 0 : nrows);
+}
+
+/* Flush the current output buffers now */
+void PNGAPI
+png_write_flush(png_structp png_ptr)
+{
+   int wrote_IDAT;
+
+   png_debug(1, "in png_write_flush");
+
+   if (png_ptr == NULL)
+      return;
+
+   /* We have already written out all of the data */
+   if (png_ptr->row_number >= png_ptr->num_rows)
+      return;
+
+   do
+   {
+      int ret;
+
+      /* Compress the data */
+      ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
+      wrote_IDAT = 0;
+
+      /* Check for compression errors */
+      if (ret != Z_OK)
+      {
+         if (png_ptr->zstream.msg != NULL)
+            png_error(png_ptr, png_ptr->zstream.msg);
+
+         else
+            png_error(png_ptr, "zlib error");
+      }
+
+      if (!(png_ptr->zstream.avail_out))
+      {
+         /* Write the IDAT and reset the zlib output buffer */
+         png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
+         wrote_IDAT = 1;
+      }
+   } while (wrote_IDAT == 1);
+
+   /* If there is any data left to be output, write it into a new IDAT */
+   if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
+   {
+      /* Write the IDAT and reset the zlib output buffer */
+      png_write_IDAT(png_ptr, png_ptr->zbuf,
+          png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+   }
+   png_ptr->flush_rows = 0;
+   png_flush(png_ptr);
+}
+#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+
+/* Free all memory used by the write */
+void PNGAPI
+png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
+{
+   png_structp png_ptr = NULL;
+   png_infop info_ptr = NULL;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_free_ptr free_fn = NULL;
+   png_voidp mem_ptr = NULL;
+#endif
+
+   png_debug(1, "in png_destroy_write_struct");
+
+   if (png_ptr_ptr != NULL)
+      png_ptr = *png_ptr_ptr;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if (png_ptr != NULL)
+   {
+      free_fn = png_ptr->free_fn;
+      mem_ptr = png_ptr->mem_ptr;
+   }
+#endif
+
+   if (info_ptr_ptr != NULL)
+      info_ptr = *info_ptr_ptr;
+
+   if (info_ptr != NULL)
+   {
+      if (png_ptr != NULL)
+      {
+         png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+         if (png_ptr->num_chunk_list)
+         {
+            png_free(png_ptr, png_ptr->chunk_list);
+            png_ptr->num_chunk_list = 0;
+         }
+#endif
+      }
+
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
+          (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)info_ptr);
+#endif
+      *info_ptr_ptr = NULL;
+   }
+
+   if (png_ptr != NULL)
+   {
+      png_write_destroy(png_ptr);
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
+          (png_voidp)mem_ptr);
+#else
+      png_destroy_struct((png_voidp)png_ptr);
+#endif
+      *png_ptr_ptr = NULL;
+   }
+}
+
+
+/* Free any memory used in png_ptr struct (old method) */
+void /* PRIVATE */
+png_write_destroy(png_structp png_ptr)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+   jmp_buf tmp_jmp; /* Save jump buffer */
+#endif
+   png_error_ptr error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
+   png_error_ptr warning_fn;
+#endif
+   png_voidp error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_free_ptr free_fn;
+#endif
+
+   png_debug(1, "in png_write_destroy");
+
+   /* Free any memory zlib uses */
+   if (png_ptr->zlib_state != PNG_ZLIB_UNINITIALIZED)
+      deflateEnd(&png_ptr->zstream);
+
+   /* Free our memory.  png_free checks NULL for us. */
+   png_free(png_ptr, png_ptr->zbuf);
+   png_free(png_ptr, png_ptr->row_buf);
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+   png_free(png_ptr, png_ptr->prev_row);
+   png_free(png_ptr, png_ptr->sub_row);
+   png_free(png_ptr, png_ptr->up_row);
+   png_free(png_ptr, png_ptr->avg_row);
+   png_free(png_ptr, png_ptr->paeth_row);
+#endif
+
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+   /* Use this to save a little code space, it doesn't free the filter_costs */
+   png_reset_filter_heuristics(png_ptr);
+   png_free(png_ptr, png_ptr->filter_costs);
+   png_free(png_ptr, png_ptr->inv_filter_costs);
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+   /* Reset structure */
+   png_memcpy(tmp_jmp, png_ptr->longjmp_buffer, png_sizeof(jmp_buf));
+#endif
+
+   error_fn = png_ptr->error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
+   warning_fn = png_ptr->warning_fn;
+#endif
+   error_ptr = png_ptr->error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   free_fn = png_ptr->free_fn;
+#endif
+
+   png_memset(png_ptr, 0, png_sizeof(png_struct));
+
+   png_ptr->error_fn = error_fn;
+#ifdef PNG_WARNINGS_SUPPORTED
+   png_ptr->warning_fn = warning_fn;
+#endif
+   png_ptr->error_ptr = error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_ptr->free_fn = free_fn;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+   png_memcpy(png_ptr->longjmp_buffer, tmp_jmp, png_sizeof(jmp_buf));
+#endif
+}
+
+/* Allow the application to select one or more row filters to use. */
+void PNGAPI
+png_set_filter(png_structp png_ptr, int method, int filters)
+{
+   png_debug(1, "in png_set_filter");
+
+   if (png_ptr == NULL)
+      return;
+
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+       (method == PNG_INTRAPIXEL_DIFFERENCING))
+      method = PNG_FILTER_TYPE_BASE;
+
+#endif
+   if (method == PNG_FILTER_TYPE_BASE)
+   {
+      switch (filters & (PNG_ALL_FILTERS | 0x07))
+      {
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+         case 5:
+         case 6:
+         case 7: png_warning(png_ptr, "Unknown row filter for method 0");
+#endif /* PNG_WRITE_FILTER_SUPPORTED */
+         case PNG_FILTER_VALUE_NONE:
+            png_ptr->do_filter = PNG_FILTER_NONE; break;
+
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+         case PNG_FILTER_VALUE_SUB:
+            png_ptr->do_filter = PNG_FILTER_SUB; break;
+
+         case PNG_FILTER_VALUE_UP:
+            png_ptr->do_filter = PNG_FILTER_UP; break;
+
+         case PNG_FILTER_VALUE_AVG:
+            png_ptr->do_filter = PNG_FILTER_AVG; break;
+
+         case PNG_FILTER_VALUE_PAETH:
+            png_ptr->do_filter = PNG_FILTER_PAETH; break;
+
+         default:
+            png_ptr->do_filter = (png_byte)filters; break;
+#else
+         default:
+            png_warning(png_ptr, "Unknown row filter for method 0");
+#endif /* PNG_WRITE_FILTER_SUPPORTED */
+      }
+
+      /* If we have allocated the row_buf, this means we have already started
+       * with the image and we should have allocated all of the filter buffers
+       * that have been selected.  If prev_row isn't already allocated, then
+       * it is too late to start using the filters that need it, since we
+       * will be missing the data in the previous row.  If an application
+       * wants to start and stop using particular filters during compression,
+       * it should start out with all of the filters, and then add and
+       * remove them after the start of compression.
+       */
+      if (png_ptr->row_buf != NULL)
+      {
+#ifdef PNG_WRITE_FILTER_SUPPORTED
+         if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
+         {
+            png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
+                (png_ptr->rowbytes + 1));
+            png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Up filter after starting");
+               png_ptr->do_filter = (png_byte)(png_ptr->do_filter &
+                   ~PNG_FILTER_UP);
+            }
+
+            else
+            {
+               png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
+                   (png_ptr->rowbytes + 1));
+               png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
+            }
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Average filter after starting");
+               png_ptr->do_filter = (png_byte)(png_ptr->do_filter &
+                   ~PNG_FILTER_AVG);
+            }
+
+            else
+            {
+               png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
+                   (png_ptr->rowbytes + 1));
+               png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
+            }
+         }
+
+         if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
+             png_ptr->paeth_row == NULL)
+         {
+            if (png_ptr->prev_row == NULL)
+            {
+               png_warning(png_ptr, "Can't add Paeth filter after starting");
+               png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
+            }
+
+            else
+            {
+               png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
+                   (png_ptr->rowbytes + 1));
+               png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
+            }
+         }
+
+         if (png_ptr->do_filter == PNG_NO_FILTERS)
+#endif /* PNG_WRITE_FILTER_SUPPORTED */
+            png_ptr->do_filter = PNG_FILTER_NONE;
+      }
+   }
+   else
+      png_error(png_ptr, "Unknown custom filter method");
+}
+
+/* This allows us to influence the way in which libpng chooses the "best"
+ * filter for the current scanline.  While the "minimum-sum-of-absolute-
+ * differences metric is relatively fast and effective, there is some
+ * question as to whether it can be improved upon by trying to keep the
+ * filtered data going to zlib more consistent, hopefully resulting in
+ * better compression.
+ */
+#ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED      /* GRR 970116 */
+/* Convenience reset API. */
+static void
+png_reset_filter_heuristics(png_structp png_ptr)
+{
+   /* Clear out any old values in the 'weights' - this must be done because if
+    * the app calls set_filter_heuristics multiple times with different
+    * 'num_weights' values we would otherwise potentially have wrong sized
+    * arrays.
+    */
+   png_ptr->num_prev_filters = 0;
+   png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
+   if (png_ptr->prev_filters != NULL)
+   {
+      png_bytep old = png_ptr->prev_filters;
+      png_ptr->prev_filters = NULL;
+      png_free(png_ptr, old);
+   }
+   if (png_ptr->filter_weights != NULL)
+   {
+      png_uint_16p old = png_ptr->filter_weights;
+      png_ptr->filter_weights = NULL;
+      png_free(png_ptr, old);
+   }
+
+   if (png_ptr->inv_filter_weights != NULL)
+   {
+      png_uint_16p old = png_ptr->inv_filter_weights;
+      png_ptr->inv_filter_weights = NULL;
+      png_free(png_ptr, old);
+   }
+
+   /* Leave the filter_costs - this array is fixed size. */
+}
+
+static int
+png_init_filter_heuristics(png_structp png_ptr, int heuristic_method,
+   int num_weights)
+{
+   if (png_ptr == NULL)
+      return 0;
+
+   /* Clear out the arrays */
+   png_reset_filter_heuristics(png_ptr);
+
+   /* Check arguments; the 'reset' function makes the correct settings for the
+    * unweighted case, but we must handle the weight case by initializing the
+    * arrays for the caller.
+    */
+   if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+   {
+      int i;
+
+      if (num_weights > 0)
+      {
+         png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
+             (png_uint_32)(png_sizeof(png_byte) * num_weights));
+
+         /* To make sure that the weighting starts out fairly */
+         for (i = 0; i < num_weights; i++)
+         {
+            png_ptr->prev_filters[i] = 255;
+         }
+
+         png_ptr->filter_weights = (png_uint_16p)png_malloc(png_ptr,
+             (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
+
+         png_ptr->inv_filter_weights = (png_uint_16p)png_malloc(png_ptr,
+             (png_uint_32)(png_sizeof(png_uint_16) * num_weights));
+
+         for (i = 0; i < num_weights; i++)
+         {
+            png_ptr->inv_filter_weights[i] =
+            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+         }
+
+         /* Safe to set this now */
+         png_ptr->num_prev_filters = (png_byte)num_weights;
+      }
+
+      /* If, in the future, there are other filter methods, this would
+       * need to be based on png_ptr->filter.
+       */
+      if (png_ptr->filter_costs == NULL)
+      {
+         png_ptr->filter_costs = (png_uint_16p)png_malloc(png_ptr,
+             (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
+
+         png_ptr->inv_filter_costs = (png_uint_16p)png_malloc(png_ptr,
+             (png_uint_32)(png_sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));
+      }
+
+      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
+      {
+         png_ptr->inv_filter_costs[i] =
+         png_ptr->filter_costs[i] = PNG_COST_FACTOR;
+      }
+
+      /* All the arrays are inited, safe to set this: */
+      png_ptr->heuristic_method = PNG_FILTER_HEURISTIC_WEIGHTED;
+
+      /* Return the 'ok' code. */
+      return 1;
+   }
+   else if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT ||
+      heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
+   {
+      return 1;
+   }
+   else
+   {
+      png_warning(png_ptr, "Unknown filter heuristic method");
+      return 0;
+   }
+}
+
+/* Provide floating and fixed point APIs */
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
+    int num_weights, png_const_doublep filter_weights,
+    png_const_doublep filter_costs)
+{
+   png_debug(1, "in png_set_filter_heuristics");
+
+   /* The internal API allocates all the arrays and ensures that the elements of
+    * those arrays are set to the default value.
+    */
+   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
+      return;
+
+   /* If using the weighted method copy in the weights. */
+   if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+   {
+      int i;
+      for (i = 0; i < num_weights; i++)
+      {
+         if (filter_weights[i] <= 0.0)
+         {
+            png_ptr->inv_filter_weights[i] =
+            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+         }
+
+         else
+         {
+            png_ptr->inv_filter_weights[i] =
+                (png_uint_16)(PNG_WEIGHT_FACTOR*filter_weights[i]+.5);
+
+            png_ptr->filter_weights[i] =
+                (png_uint_16)(PNG_WEIGHT_FACTOR/filter_weights[i]+.5);
+         }
+      }
+
+      /* Here is where we set the relative costs of the different filters.  We
+       * should take the desired compression level into account when setting
+       * the costs, so that Paeth, for instance, has a high relative cost at low
+       * compression levels, while it has a lower relative cost at higher
+       * compression settings.  The filter types are in order of increasing
+       * relative cost, so it would be possible to do this with an algorithm.
+       */
+      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++) if (filter_costs[i] >= 1.0)
+      {
+         png_ptr->inv_filter_costs[i] =
+             (png_uint_16)(PNG_COST_FACTOR / filter_costs[i] + .5);
+
+         png_ptr->filter_costs[i] =
+             (png_uint_16)(PNG_COST_FACTOR * filter_costs[i] + .5);
+      }
+   }
+}
+#endif /* FLOATING_POINT */
+
+#ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_filter_heuristics_fixed(png_structp png_ptr, int heuristic_method,
+    int num_weights, png_const_fixed_point_p filter_weights,
+    png_const_fixed_point_p filter_costs)
+{
+   png_debug(1, "in png_set_filter_heuristics_fixed");
+
+   /* The internal API allocates all the arrays and ensures that the elements of
+    * those arrays are set to the default value.
+    */
+   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
+      return;
+
+   /* If using the weighted method copy in the weights. */
+   if (heuristic_method == PNG_FILTER_HEURISTIC_WEIGHTED)
+   {
+      int i;
+      for (i = 0; i < num_weights; i++)
+      {
+         if (filter_weights[i] <= 0)
+         {
+            png_ptr->inv_filter_weights[i] =
+            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
+         }
+
+         else
+         {
+            png_ptr->inv_filter_weights[i] = (png_uint_16)
+               ((PNG_WEIGHT_FACTOR*filter_weights[i]+PNG_FP_HALF)/PNG_FP_1);
+
+            png_ptr->filter_weights[i] = (png_uint_16)((PNG_WEIGHT_FACTOR*
+               PNG_FP_1+(filter_weights[i]/2))/filter_weights[i]);
+         }
+      }
+
+      /* Here is where we set the relative costs of the different filters.  We
+       * should take the desired compression level into account when setting
+       * the costs, so that Paeth, for instance, has a high relative cost at low
+       * compression levels, while it has a lower relative cost at higher
+       * compression settings.  The filter types are in order of increasing
+       * relative cost, so it would be possible to do this with an algorithm.
+       */
+      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
+         if (filter_costs[i] >= PNG_FP_1)
+      {
+         png_uint_32 tmp;
+
+         /* Use a 32 bit unsigned temporary here because otherwise the
+          * intermediate value will be a 32 bit *signed* integer (ANSI rules)
+          * and this will get the wrong answer on division.
+          */
+         tmp = PNG_COST_FACTOR*PNG_FP_1 + (filter_costs[i]/2);
+         tmp /= filter_costs[i];
+
+         png_ptr->inv_filter_costs[i] = (png_uint_16)tmp;
+
+         tmp = PNG_COST_FACTOR * filter_costs[i] + PNG_FP_HALF;
+         tmp /= PNG_FP_1;
+
+         png_ptr->filter_costs[i] = (png_uint_16)tmp;
+      }
+   }
+}
+#endif /* FIXED_POINT */
+#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+
+void PNGAPI
+png_set_compression_level(png_structp png_ptr, int level)
+{
+   png_debug(1, "in png_set_compression_level");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_LEVEL;
+   png_ptr->zlib_level = level;
+}
+
+void PNGAPI
+png_set_compression_mem_level(png_structp png_ptr, int mem_level)
+{
+   png_debug(1, "in png_set_compression_mem_level");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_MEM_LEVEL;
+   png_ptr->zlib_mem_level = mem_level;
+}
+
+void PNGAPI
+png_set_compression_strategy(png_structp png_ptr, int strategy)
+{
+   png_debug(1, "in png_set_compression_strategy");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_STRATEGY;
+   png_ptr->zlib_strategy = strategy;
+}
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+void PNGAPI
+png_set_compression_window_bits(png_structp png_ptr, int window_bits)
+{
+   if (png_ptr == NULL)
+      return;
+
+   if (window_bits > 15)
+      png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
+
+   else if (window_bits < 8)
+      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
+
+#ifndef WBITS_8_OK
+   /* Avoid libpng bug with 256-byte windows */
+   if (window_bits == 8)
+      {
+        png_warning(png_ptr, "Compression window is being reset to 512");
+        window_bits = 9;
+      }
+
+#endif
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
+   png_ptr->zlib_window_bits = window_bits;
+}
+
+void PNGAPI
+png_set_compression_method(png_structp png_ptr, int method)
+{
+   png_debug(1, "in png_set_compression_method");
+
+   if (png_ptr == NULL)
+      return;
+
+   if (method != 8)
+      png_warning(png_ptr, "Only compression method 8 is supported by PNG");
+
+   png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_METHOD;
+   png_ptr->zlib_method = method;
+}
+
+/* The following were added to libpng-1.5.4 */
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+void PNGAPI
+png_set_text_compression_level(png_structp png_ptr, int level)
+{
+   png_debug(1, "in png_set_text_compression_level");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_LEVEL;
+   png_ptr->zlib_text_level = level;
+}
+
+void PNGAPI
+png_set_text_compression_mem_level(png_structp png_ptr, int mem_level)
+{
+   png_debug(1, "in png_set_text_compression_mem_level");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL;
+   png_ptr->zlib_text_mem_level = mem_level;
+}
+
+void PNGAPI
+png_set_text_compression_strategy(png_structp png_ptr, int strategy)
+{
+   png_debug(1, "in png_set_text_compression_strategy");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_STRATEGY;
+   png_ptr->zlib_text_strategy = strategy;
+}
+
+/* If PNG_WRITE_OPTIMIZE_CMF_SUPPORTED is defined, libpng will use a
+ * smaller value of window_bits if it can do so safely.
+ */
+void PNGAPI
+png_set_text_compression_window_bits(png_structp png_ptr, int window_bits)
+{
+   if (png_ptr == NULL)
+      return;
+
+   if (window_bits > 15)
+      png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
+
+   else if (window_bits < 8)
+      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
+
+#ifndef WBITS_8_OK
+   /* Avoid libpng bug with 256-byte windows */
+   if (window_bits == 8)
+      {
+        png_warning(png_ptr, "Text compression window is being reset to 512");
+        window_bits = 9;
+      }
+
+#endif
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS;
+   png_ptr->zlib_text_window_bits = window_bits;
+}
+
+void PNGAPI
+png_set_text_compression_method(png_structp png_ptr, int method)
+{
+   png_debug(1, "in png_set_text_compression_method");
+
+   if (png_ptr == NULL)
+      return;
+
+   if (method != 8)
+      png_warning(png_ptr, "Only compression method 8 is supported by PNG");
+
+   png_ptr->flags |= PNG_FLAG_ZTXT_CUSTOM_METHOD;
+   png_ptr->zlib_text_method = method;
+}
+#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+/* end of API added to libpng-1.5.4 */
+
+void PNGAPI
+png_set_write_status_fn(png_structp png_ptr, png_write_status_ptr write_row_fn)
+{
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->write_row_fn = write_row_fn;
+}
+
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+void PNGAPI
+png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
+    write_user_transform_fn)
+{
+   png_debug(1, "in png_set_write_user_transform_fn");
+
+   if (png_ptr == NULL)
+      return;
+
+   png_ptr->transformations |= PNG_USER_TRANSFORM;
+   png_ptr->write_user_transform_fn = write_user_transform_fn;
+}
+#endif
+
+
+#ifdef PNG_INFO_IMAGE_SUPPORTED
+void PNGAPI
+png_write_png(png_structp png_ptr, png_infop info_ptr,
+    int transforms, voidp params)
+{
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   /* Write the file header information. */
+   png_write_info(png_ptr, info_ptr);
+
+   /* ------ these transformations don't touch the info structure ------- */
+
+#ifdef PNG_WRITE_INVERT_SUPPORTED
+   /* Invert monochrome pixels */
+   if (transforms & PNG_TRANSFORM_INVERT_MONO)
+      png_set_invert_mono(png_ptr);
+#endif
+
+#ifdef PNG_WRITE_SHIFT_SUPPORTED
+   /* Shift the pixels up to a legal bit depth and fill in
+    * as appropriate to correctly scale the image.
+    */
+   if ((transforms & PNG_TRANSFORM_SHIFT)
+       && (info_ptr->valid & PNG_INFO_sBIT))
+      png_set_shift(png_ptr, &info_ptr->sig_bit);
+#endif
+
+#ifdef PNG_WRITE_PACK_SUPPORTED
+   /* Pack pixels into bytes */
+   if (transforms & PNG_TRANSFORM_PACKING)
+       png_set_packing(png_ptr);
+#endif
+
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
+   /* Swap location of alpha bytes from ARGB to RGBA */
+   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+      png_set_swap_alpha(png_ptr);
+#endif
+
+#ifdef PNG_WRITE_FILLER_SUPPORTED
+   /* Pack XRGB/RGBX/ARGB/RGBA into RGB (4 channels -> 3 channels) */
+   if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER)
+      png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
+
+   else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)
+      png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+#endif
+
+#ifdef PNG_WRITE_BGR_SUPPORTED
+   /* Flip BGR pixels to RGB */
+   if (transforms & PNG_TRANSFORM_BGR)
+      png_set_bgr(png_ptr);
+#endif
+
+#ifdef PNG_WRITE_SWAP_SUPPORTED
+   /* Swap bytes of 16-bit files to most significant byte first */
+   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+      png_set_swap(png_ptr);
+#endif
+
+#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
+   /* Swap bits of 1, 2, 4 bit packed pixel formats */
+   if (transforms & PNG_TRANSFORM_PACKSWAP)
+      png_set_packswap(png_ptr);
+#endif
+
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
+   /* Invert the alpha channel from opacity to transparency */
+   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+      png_set_invert_alpha(png_ptr);
+#endif
+
+   /* ----------------------- end of transformations ------------------- */
+
+   /* Write the bits */
+   if (info_ptr->valid & PNG_INFO_IDAT)
+       png_write_image(png_ptr, info_ptr->row_pointers);
+
+   /* It is REQUIRED to call this to finish writing the rest of the file */
+   png_write_end(png_ptr, info_ptr);
+
+   PNG_UNUSED(transforms)   /* Quiet compiler warnings */
+   PNG_UNUSED(params)
+}
+#endif
+#endif /* PNG_WRITE_SUPPORTED */