Merge d032483ed471b76ec56d89e5a7e5951917fe5562 into b2fc82f3a8248e54707e1f21e29fa9b2a7831d73

Add libpng_native to VC++ projects.

.github/workflows/build.yml

@@ -17,7 +17,7 @@ jobs:
     - name: Update Build Environment
       run: sudo apt-get update --fix-missing -y
     - name: Install Prerequisites
-      run: sudo apt-get install -y cppcheck zlib1g-dev
+      run: sudo apt-get install -y cppcheck zlib1g-dev libpng-dev
     - name: Configure PDFio
       run: ./configure --enable-debug --enable-sanitizer --enable-maintainer
     - name: Build PDFio

.github/workflows/codeql.yml

@@ -32,7 +32,7 @@ jobs:
         run: sudo apt-get update --fix-missing -y
 
       - name: Install Prerequisites
-        run: sudo apt-get install -y zlib1g-dev
+        run: sudo apt-get install -y zlib1g-dev libpng-dev
 
       - name: Initialize CodeQL
         uses: github/codeql-action/init@v2

.github/workflows/coverity.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Update Build Environment
         run: sudo apt-get update --fix-missing -y
       - name: Install Prerequisites
-        run: sudo apt-get install -y zlib1g-dev
+        run: sudo apt-get install -y zlib1g-dev libpng-dev
       - name: Download Coverity Build Tool
         run: |
           wget -q https://scan.coverity.com/download/linux64 --post-data token="$TOKEN&project=$GITHUB_REPOSITORY" -O cov-analysis-linux64.tar.gz

CHANGES.md

@@ -1,9 +1,10 @@
 Changes in PDFio
 ================
 
-v1.?.? - YYYY-MM-DD
+v1.5.0 - YYYY-MM-DD
 -------------------
 
+- Added support for using libpng to embed PNG images in PDF output (Issue #90)
 - Updated the pdf2txt example to support font encodings.
 
 

configure

@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.71 for pdfio 1.4.1.
+# Generated by GNU Autoconf 2.71 for pdfio 1.5.0.
 #
 # Report bugs to <https://github.com/michaelrsweet/pdfio/issues>.
 #
@@ -610,8 +610,8 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='pdfio'
 PACKAGE_TARNAME='pdfio'
-PACKAGE_VERSION='1.4.1'
-PACKAGE_STRING='pdfio 1.4.1'
+PACKAGE_VERSION='1.5.0'
+PACKAGE_STRING='pdfio 1.5.0'
 PACKAGE_BUGREPORT='https://github.com/michaelrsweet/pdfio/issues'
 PACKAGE_URL='https://www.msweet.org/pdfio'
 
@@ -653,6 +653,7 @@ WARNINGS
 CSFLAGS
 LIBPDFIO_STATIC
 LIBPDFIO
+PKGCONFIG_LIBPNG
 PKGCONFIG_REQUIRES
 PKGCONFIG_LIBS_PRIVATE
 PKGCONFIG_LIBS
@@ -729,6 +730,7 @@ SHELL'
 ac_subst_files=''
 ac_user_opts='
 enable_option_checking
+enable_libpng
 enable_static
 enable_shared
 enable_debug
@@ -1293,7 +1295,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures pdfio 1.4.1 to adapt to many kinds of systems.
+\`configure' configures pdfio 1.5.0 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1359,7 +1361,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of pdfio 1.4.1:";;
+     short | recursive ) echo "Configuration of pdfio 1.5.0:";;
    esac
   cat <<\_ACEOF
 
@@ -1367,6 +1369,8 @@ Optional Features:
   --disable-option-checking  ignore unrecognized --enable/--with options
   --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
   --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
+  --enable-libpng         use libpng for pdfioFileCreateImageObjFromFile,
+                          default=auto
   --disable-static        do not install static library
   --enable-shared         install shared library
   --enable-debug          turn on debugging, default=no
@@ -1456,7 +1460,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-pdfio configure 1.4.1
+pdfio configure 1.5.0
 generated by GNU Autoconf 2.71
 
 Copyright (C) 2021 Free Software Foundation, Inc.
@@ -1612,7 +1616,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by pdfio $as_me 1.4.1, which was
+It was created by pdfio $as_me 1.5.0, which was
 generated by GNU Autoconf 2.71.  Invocation command line was
 
   $ $0$ac_configure_args_raw
@@ -2368,9 +2372,9 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
-PDFIO_VERSION="1.4.1"
-PDFIO_VERSION_MAJOR="`echo 1.4.1 | awk -F. '{print $1}'`"
-PDFIO_VERSION_MINOR="`echo 1.4.1 | awk -F. '{printf("%d\n",$2);}'`"
+PDFIO_VERSION="1.5.0"
+PDFIO_VERSION_MAJOR="`echo 1.5.0 | awk -F. '{print $1}'`"
+PDFIO_VERSION_MINOR="`echo 1.5.0 | awk -F. '{printf("%d\n",$2);}'`"
 
 
 
@@ -4099,6 +4103,55 @@ fi
 fi
 
 
+# Check whether --enable-libpng was given.
+if test ${enable_libpng+y}
+then :
+  enableval=$enable_libpng;
+fi
+
+
+PKGCONFIG_LIBPNG=""
+
+
+if test "x$PKGCONFIG" != x -a x$enable_libpng != xno
+then :
+
+    { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for libpng-1.6.x" >&5
+printf %s "checking for libpng-1.6.x... " >&6; }
+    if $PKGCONFIG --exists libpng16
+then :
+
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+printf "%s\n" "yes" >&6; };
+
+printf "%s\n" "#define HAVE_LIBPNG 1" >>confdefs.h
+
+	CPPFLAGS="$($PKGCONFIG --cflags libpng16) -DHAVE_LIBPNG=1 $CPPFLAGS"
+	LIBS="$($PKGCONFIG --libs libpng16) -lz $LIBS"
+	PKGCONFIG_LIBPNG="libpng >= 1.6,"
+	PKGCONFIG_LIBS_PRIVATE="$($PKGCONFIG --libs libpng16) $PKGCONFIG_LIBS_PRIVATE"
+
+else $as_nop
+
+	{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: no" >&5
+printf "%s\n" "no" >&6; };
+	if test x$enable_libpng = xyes
+then :
+
+	    as_fn_error $? "libpng-dev 1.6 or later required for --enable-libpng." "$LINENO" 5
+
+fi
+
+fi
+
+elif test x$enable_libpng = xyes
+then :
+
+    as_fn_error $? "libpng-dev 1.6 or later required for --enable-libpng." "$LINENO" 5
+
+fi
+
+
 # Check whether --enable-static was given.
 if test ${enable_static+y}
 then :
@@ -4935,7 +4988,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by pdfio $as_me 1.4.1, which was
+This file was extended by pdfio $as_me 1.5.0, which was
 generated by GNU Autoconf 2.71.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -4991,7 +5044,7 @@ ac_cs_config_escaped=`printf "%s\n" "$ac_cs_config" | sed "s/^ //; s/'/'\\\\\\\\
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config='$ac_cs_config_escaped'
 ac_cs_version="\\
-pdfio config.status 1.4.1
+pdfio config.status 1.5.0
 configured by $0, generated by GNU Autoconf 2.71,
   with options \\"\$ac_cs_config\\"
 

configure.ac

@@ -1,7 +1,7 @@
 dnl
 dnl Configuration script for PDFio
 dnl
-dnl Copyright © 2023-2024 by Michael R Sweet
+dnl Copyright © 2023-2025 by Michael R Sweet
 dnl
 dnl Licensed under Apache License v2.0.  See the file "LICENSE" for more
 dnl information.
@@ -21,7 +21,7 @@ AC_PREREQ([2.70])
 
 
 dnl Package name and version...
-AC_INIT([pdfio], [1.4.1], [https://github.com/michaelrsweet/pdfio/issues], [pdfio], [https://www.msweet.org/pdfio])
+AC_INIT([pdfio], [1.5.0], [https://github.com/michaelrsweet/pdfio/issues], [pdfio], [https://www.msweet.org/pdfio])
 
 PDFIO_VERSION="AC_PACKAGE_VERSION"
 PDFIO_VERSION_MAJOR="`echo AC_PACKAGE_VERSION | awk -F. '{print $1}'`"
@@ -121,6 +121,32 @@ AS_IF([$PKGCONFIG --exists zlib], [
 ])
 
 
+dnl libpng...
+AC_ARG_ENABLE([libpng], AS_HELP_STRING([--enable-libpng], [use libpng for pdfioFileCreateImageObjFromFile, default=auto]))
+
+PKGCONFIG_LIBPNG=""
+AC_SUBST([PKGCONFIG_LIBPNG])
+
+AS_IF([test "x$PKGCONFIG" != x -a x$enable_libpng != xno], [
+    AC_MSG_CHECKING([for libpng-1.6.x])
+    AS_IF([$PKGCONFIG --exists libpng16], [
+	AC_MSG_RESULT([yes]);
+	AC_DEFINE([HAVE_LIBPNG], 1, [Have PNG library?])
+	CPPFLAGS="$($PKGCONFIG --cflags libpng16) -DHAVE_LIBPNG=1 $CPPFLAGS"
+	LIBS="$($PKGCONFIG --libs libpng16) -lz $LIBS"
+	PKGCONFIG_LIBPNG="libpng >= 1.6,"
+	PKGCONFIG_LIBS_PRIVATE="$($PKGCONFIG --libs libpng16) $PKGCONFIG_LIBS_PRIVATE"
+    ], [
+	AC_MSG_RESULT([no]);
+	AS_IF([test x$enable_libpng = xyes], [
+	    AC_MSG_ERROR([libpng-dev 1.6 or later required for --enable-libpng.])
+	])
+    ])
+], [test x$enable_libpng = xyes], [
+    AC_MSG_ERROR([libpng-dev 1.6 or later required for --enable-libpng.])
+])
+
+
 dnl Library target...
 AC_ARG_ENABLE([static], AS_HELP_STRING([--disable-static], [do not install static library]))
 AC_ARG_ENABLE([shared], AS_HELP_STRING([--enable-shared], [install shared library]))

examples/Makefile

@@ -14,8 +14,8 @@
 # Common options
 CFLAGS		=	-g $(CPPFLAGS)
 #CFLAGS		=	-g -fsanitize=address $(CPPFLAGS)
-CPPFLAGS	=	-I.. -I/usr/local/include
-LIBS		=	-L.. -L/usr/local/lib -lpdfio -lz -lm
+CPPFLAGS	=	-I.. $(shell PKG_CONFIG_PATH="..:$(PKG_CONFIG_PATH)" pkg-config pdfio --cflags)
+LIBS		=	-L.. $(shell PKG_CONFIG_PATH="..:$(PKG_CONFIG_PATH)" pkg-config pdfio --libs)
 
 
 # Targets

examples/image2pdf.c

@@ -1,7 +1,7 @@
 //
 // Image example for PDFio.
 //
-// Copyright © 2023-2024 by Michael R Sweet.
+// Copyright © 2023-2025 by Michael R Sweet.
 //
 // Licensed under Apache License v2.0.  See the file "LICENSE" for more
 // information.
@@ -22,8 +22,8 @@
 
 bool					// O - True on success, false on failure
 create_pdf_image_file(
-    const char *pdfname,		// I - PDF filename
     const char *imagename,		// I - Image filename
+    const char *pdfname,		// I - PDF filename
     const char *caption)		// I - Caption filename
 {
   pdfio_file_t   *pdf;			// PDF file
@@ -36,6 +36,15 @@ create_pdf_image_file(
   double         tx, ty;		// Position on page
 
 
+  // Default the caption...
+  if (!caption)
+  {
+    if ((caption = strrchr(imagename, '/')) != NULL)
+      caption ++;
+    else
+      caption = imagename;
+  }
+
   // Create the PDF file...
   pdf = pdfioFileCreate(pdfname, /*version*/NULL, /*media_box*/NULL,
                         /*crop_box*/NULL, /*error_cb*/NULL,

examples/pdfioinfo.c

@@ -25,11 +25,18 @@ main(int  argc,				// I - Number of command-line arguments
 {
   const char	*filename;		// PDF filename
   pdfio_file_t	*pdf;			// PDF file
-  const char	*author;		// Author name
-  time_t	creation_date;		// Creation date
-  struct tm	*creation_tm;		// Creation date/time information
-  char		creation_text[256];	// Creation date/time as a string
+  const char	*author,		// Author name
+  		*creator,		// Creator name
+  		*producer;		// Producer name
+  time_t	creation_date,		// Creation date
+		mod_date;		// Modification date
+  struct tm	*creation_tm,		// Creation date/time information
+		*mod_tm;		// Mod. date/time information
+  char		creation_text[256],	// Creation date/time as a string
+		mod_text[256];		// Mod. date/time human fmt string
   const char	*title;			// Title
+  size_t	num_pages;		// PDF number of pages
+  bool		has_acroform;		// AcroForm or not
 
 
   // Get the filename from the command-line...
@@ -48,9 +55,12 @@ main(int  argc,				// I - Number of command-line arguments
   if (pdf == NULL)
     return (1);
 
-  // Get the title and author...
+  // Get the title, author...
   author = pdfioFileGetAuthor(pdf);
   title  = pdfioFileGetTitle(pdf);
+  creator = pdfioFileGetCreator(pdf);
+  producer = pdfioFileGetProducer(pdf);
+  num_pages = pdfioFileGetNumPages(pdf);
 
   // Get the creation date and convert to a string...
   if ((creation_date = pdfioFileGetCreationDate(pdf)) > 0)
@@ -63,12 +73,82 @@ main(int  argc,				// I - Number of command-line arguments
     snprintf(creation_text, sizeof(creation_text), "-- not set --");
   }
 
+  // Get the modification date and convert to a string...
+  if ((mod_date = pdfioFileGetModDate(pdf)) > 0)
+  {
+    mod_tm   = localtime(&mod_date);
+    strftime(mod_text, sizeof(mod_text), "%c", mod_tm);
+  }
+  else
+  {
+    snprintf(mod_text, sizeof(mod_text), "-- not set --");
+  }
+
+  // Detect simply if AcroFrom is a dict in catalog
+  {
+    pdfio_dict_t	*dict;			// some Object dictionary
+   
+    dict = pdfioFileGetCatalog(pdf);
+    has_acroform = (dict != NULL && pdfioDictGetObj(dict, "AcroForm") != NULL)?
+                   true : false;
+  }
+
   // Print file information to stdout...
   printf("%s:\n", filename);
   printf("         Title: %s\n", title ? title : "-- not set --");
   printf("        Author: %s\n", author ? author : "-- not set --");
+  printf("       Creator: %s\n", creator ? creator : "-- not set --");
+  printf("      Producer: %s\n", producer ? producer : "-- not set --");
   printf("    Created On: %s\n", creation_text);
-  printf("  Number Pages: %u\n", (unsigned)pdfioFileGetNumPages(pdf));
+  printf("   Modified On: %s\n", mod_text);
+  printf("       Version: %s\n", pdfioFileGetVersion(pdf));
+  printf("      AcroForm: %s\n", has_acroform ? "Yes" : "No");
+  printf("  Number Pages: %u\n", (unsigned)num_pages);
+  printf("    MediaBoxes:");
+  // There can be a different MediaBox per page
+  // Loop and report MediaBox and number of consecutive pages of this size
+  {
+    pdfio_obj_t		*obj;			// Object
+    pdfio_dict_t	*dict;			// Object dictionary
+    pdfio_rect_t 	prev,			// MediaBox previous
+     			now;			// MediaBox now
+    size_t 		n,			// Page index
+          		nprev;			// Number previous prev size
+
+    // MediaBox should be set at least on the root
+    for (n = nprev = 0; n < num_pages; n++)
+    {
+      obj = pdfioFileGetPage(pdf, n);
+      while (obj != NULL)
+      {
+        dict = pdfioObjGetDict(obj);
+        if (pdfioDictGetRect(dict, "MediaBox", &now))
+        {
+          if ( 
+                nprev == 0
+                || (
+                     now.x1 != prev.x1 || now.y1 != prev.y1
+                     || now.x2 != prev.x2 || now.y2 != prev.y2
+                   )
+             )
+          {
+            if (nprev) printf("(%zd) ", nprev);
+            prev = now;
+            printf("[%.7g %.7g %.7g %.7g]", now.x1, now.y1, now.x2, now.y2);
+            nprev = 1;
+          }
+          else
+            ++nprev;
+	  obj = NULL;
+        }
+        else
+	  obj = pdfioDictGetObj(dict, "Parent");
+      }
+    }
+    printf("(%zd)", nprev);
+  }
+  printf("\n");
+
 
   // Close the PDF file...
   pdfioFileClose(pdf);

packages.config

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
+  <package id="libpng_native" version="1.6.30" targetFramework="native" />
+  <package id="libpng_native.redist" version="1.6.30" targetFramework="native" />
   <package id="zlib_native" version="1.2.11" targetFramework="native" />
   <package id="zlib_native.redist" version="1.2.11" targetFramework="native" />
 </packages>

pdfio-content.c

@@ -1,7 +1,7 @@
 //
 // Content helper functions for PDFio.
 //
-// Copyright © 2021-2024 by Michael R Sweet.
+// Copyright © 2021-2025 by Michael R Sweet.
 //
 // Licensed under Apache License v2.0.  See the file "LICENSE" for more
 // information.
@@ -11,6 +11,9 @@
 #include "pdfio-content.h"
 #include "pdfio-base-font-widths.h"
 #include "ttf.h"
+#ifdef HAVE_LIBPNG
+#  include <png.h>
+#endif // HAVE_LIBPNG
 #include <math.h>
 #ifndef M_PI
 #  define M_PI	3.14159265358979323846264338327950288
@@ -29,12 +32,50 @@
 #define _PDFIO_PNG_CHUNK_gAMA	0x67414d41	// Gamma correction
 #define _PDFIO_PNG_CHUNK_tRNS	0x74524e53	// Transparency information
 
+#define _PDFIO_PNG_COMPRESSION_FLATE 0	// Flate compression
+
+#define _PDFIO_PNG_FILTER_ADAPTIVE 0	// Adaptive filtering
+
+#define _PDFIO_PNG_INTERLACE_NONE 0	// No interlacing
+#define _PDFIO_PNG_INTERLACE_ADAM 1	// "Adam7" interlacing
+
 #define _PDFIO_PNG_TYPE_GRAY	0	// Grayscale
 #define _PDFIO_PNG_TYPE_RGB	2	// RGB
 #define _PDFIO_PNG_TYPE_INDEXED	3	// Indexed
 #define _PDFIO_PNG_TYPE_GRAYA	4	// Grayscale + alpha
 #define _PDFIO_PNG_TYPE_RGBA	6	// RGB + alpha
 
+
+//
+// Local types...
+//
+
+typedef pdfio_obj_t *(*_pdfio_image_func_t)(pdfio_dict_t *dict, int fd);
+
+
+//
+// Local functions...
+//
+
+static pdfio_obj_t	*copy_jpeg(pdfio_dict_t *dict, int fd);
+static pdfio_obj_t	*copy_png(pdfio_dict_t *dict, int fd);
+static bool		create_cp1252(pdfio_file_t *pdf);
+static pdfio_obj_t	*create_image(pdfio_dict_t *dict, const unsigned char *data, size_t width, size_t height, size_t depth, size_t num_colors, bool alpha);
+#ifdef HAVE_LIBPNG
+static void		png_error_func(png_structp pp, png_const_charp message);
+static void		png_read_func(png_structp png_ptr, png_bytep data, size_t length);
+#endif // HAVE_LIBPNG
+static void		ttf_error_cb(pdfio_file_t *pdf, const char *message);
+#ifndef HAVE_LIBPNG
+static unsigned		update_png_crc(unsigned crc, const unsigned char *buffer, size_t length);
+#endif // !HAVE_LIBPNG
+static bool		write_string(pdfio_stream_t *st, bool unicode, const char *s, bool *newline);
+
+
+//
+// Local globals...
+//
+
 static int	_pdfio_cp1252[] =	// CP1252-specific character mapping
 {
   0x20AC,
@@ -71,30 +112,7 @@ static int	_pdfio_cp1252[] =	// CP1252-specific character mapping
   0x0178
 };
 
-
-//
-// Local types...
-//
-
-typedef pdfio_obj_t *(*_pdfio_image_func_t)(pdfio_dict_t *dict, int fd);
-
-
-//
-// Local functions...
-//
-
-static pdfio_obj_t	*copy_jpeg(pdfio_dict_t *dict, int fd);
-static pdfio_obj_t	*copy_png(pdfio_dict_t *dict, int fd);
-static bool		create_cp1252(pdfio_file_t *pdf);
-static void		ttf_error_cb(pdfio_file_t *pdf, const char *message);
-static unsigned		update_png_crc(unsigned crc, const unsigned char *buffer, size_t length);
-static bool		write_string(pdfio_stream_t *st, bool unicode, const char *s, bool *newline);
-
-
-//
-// Local globals...
-//
-
+#ifndef HAVE_LIBPNG
 static unsigned png_crc_table[256] =	// CRC-32 table for PNG files
 {
   0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
@@ -141,6 +159,7 @@ static unsigned png_crc_table[256] =	// CRC-32 table for PNG files
   0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
   0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
 };
+#endif // !HAVE_LIBPNG
 
 
 //
@@ -1976,18 +1995,7 @@ pdfioFileCreateImageObjFromData(
     bool                alpha,		// I - `true` if data contains an alpha channel
     bool                interpolate)	// I - Interpolate image data?
 {
-  pdfio_dict_t		*dict,		// Image dictionary
-			*decode;	// DecodeParms dictionary
-  pdfio_obj_t		*obj,		// Image object
-			*mask_obj = NULL;
-					// Mask image object, if any
-  pdfio_stream_t	*st;		// Image stream
-  size_t		x, y,		// X and Y position in image
-			bpp,		// Bytes per pixel
-			linelen;	// Line length
-  const unsigned char	*dataptr;	// Pointer into image data
-  unsigned char		*line = NULL,	// Current line
-			*lineptr;	// Pointer into line
+  pdfio_dict_t		*dict;		// Image dictionary
   static const char	*defcolors[] =	// Default ColorSpace values
   {
     NULL,
@@ -2002,74 +2010,9 @@ pdfioFileCreateImageObjFromData(
   if (!pdf || !data || !width || !height || num_colors < 1 || num_colors == 2 || num_colors > 4)
     return (NULL);
 
-  // Allocate memory for one line of data...
-  bpp     = alpha ? num_colors + 1 : num_colors;
-  linelen = num_colors * width;
-
-  if ((line = malloc(linelen)) == NULL)
-    return (NULL);
-
-  // Generate a mask image, as needed...
-  if (alpha)
-  {
-    // Create the image mask dictionary...
+  // Create the image dictionary...
   if ((dict = pdfioDictCreate(pdf)) == NULL)
-    {
-      free(line);
     return (NULL);
-    }
-
-    pdfioDictSetName(dict, "Type", "XObject");
-    pdfioDictSetName(dict, "Subtype", "Image");
-    pdfioDictSetNumber(dict, "Width", width);
-    pdfioDictSetNumber(dict, "Height", height);
-    pdfioDictSetNumber(dict, "BitsPerComponent", 8);
-    pdfioDictSetName(dict, "ColorSpace", "DeviceGray");
-    pdfioDictSetName(dict, "Filter", "FlateDecode");
-
-    if ((decode = pdfioDictCreate(pdf)) == NULL)
-    {
-      free(line);
-      return (NULL);
-    }
-
-    pdfioDictSetNumber(decode, "BitsPerComponent", 8);
-    pdfioDictSetNumber(decode, "Colors", 1);
-    pdfioDictSetNumber(decode, "Columns", width);
-    pdfioDictSetNumber(decode, "Predictor", _PDFIO_PREDICTOR_PNG_AUTO);
-    pdfioDictSetDict(dict, "DecodeParms", decode);
-
-    // Create the mask object and write the mask image...
-    if ((mask_obj = pdfioFileCreateObj(pdf, dict)) == NULL)
-    {
-      free(line);
-      return (NULL);
-    }
-
-    if ((st = pdfioObjCreateStream(mask_obj, PDFIO_FILTER_FLATE)) == NULL)
-    {
-      free(line);
-      pdfioObjClose(mask_obj);
-      return (NULL);
-    }
-
-    for (y = height, dataptr = data + num_colors; y > 0; y --)
-    {
-      for (x = width, lineptr = line; x > 0; x --, dataptr += bpp)
-        *lineptr++ = *dataptr;
-
-      pdfioStreamWrite(st, line, width);
-    }
-
-    pdfioStreamClose(st);
-  }
-
-  // Now create the image...
-  if ((dict = pdfioDictCreate(pdf)) == NULL)
-  {
-    free(line);
-    return (NULL);
-  }
 
   pdfioDictSetName(dict, "Type", "XObject");
   pdfioDictSetName(dict, "Subtype", "Image");
@@ -2077,83 +2020,14 @@ pdfioFileCreateImageObjFromData(
   pdfioDictSetNumber(dict, "Width", width);
   pdfioDictSetNumber(dict, "Height", height);
   pdfioDictSetNumber(dict, "BitsPerComponent", 8);
-  pdfioDictSetName(dict, "Filter", "FlateDecode");
 
   if (color_data)
     pdfioDictSetArray(dict, "ColorSpace", color_data);
   else
     pdfioDictSetName(dict, "ColorSpace", defcolors[num_colors]);
 
-  if (mask_obj)
-    pdfioDictSetObj(dict, "SMask", mask_obj);
-
-  if ((decode = pdfioDictCreate(pdf)) == NULL)
-  {
-    free(line);
-    return (NULL);
-  }
-
-  pdfioDictSetNumber(decode, "BitsPerComponent", 8);
-  pdfioDictSetNumber(decode, "Colors", num_colors);
-  pdfioDictSetNumber(decode, "Columns", width);
-  pdfioDictSetNumber(decode, "Predictor", _PDFIO_PREDICTOR_PNG_AUTO);
-  pdfioDictSetDict(dict, "DecodeParms", decode);
-
-  if ((obj = pdfioFileCreateObj(pdf, dict)) == NULL)
-  {
-    free(line);
-    return (NULL);
-  }
-
-  if ((st = pdfioObjCreateStream(obj, PDFIO_FILTER_FLATE)) == NULL)
-  {
-    free(line);
-    pdfioObjClose(obj);
-    return (NULL);
-  }
-
-  for (y = height, dataptr = data; y > 0; y --)
-  {
-    if (alpha)
-    {
-      switch (num_colors)
-      {
-	case 1 :
-	    for (x = width, lineptr = line; x > 0; x --, dataptr += bpp)
-	      *lineptr++ = *dataptr;
-	    break;
-	case 3 :
-	    for (x = width, lineptr = line; x > 0; x --, dataptr += bpp)
-	    {
-	      *lineptr++ = dataptr[0];
-	      *lineptr++ = dataptr[1];
-	      *lineptr++ = dataptr[2];
-	    }
-	    break;
-	case 4 :
-	    for (x = width, lineptr = line; x > 0; x --, dataptr += bpp)
-	    {
-	      *lineptr++ = dataptr[0];
-	      *lineptr++ = dataptr[1];
-	      *lineptr++ = dataptr[2];
-	      *lineptr++ = dataptr[3];
-	    }
-	    break;
-      }
-
-      pdfioStreamWrite(st, line, linelen);
-    }
-    else
-    {
-      pdfioStreamWrite(st, dataptr, linelen);
-      dataptr += linelen;
-    }
-  }
-
-  free(line);
-  pdfioStreamClose(st);
-
-  return (obj);
+  // Create the image object(s)...
+  return (create_image(dict, data, width, height, 8, num_colors, alpha));
 }
 
 
@@ -2183,6 +2057,8 @@ pdfioFileCreateImageObjFromFile(
   _pdfio_image_func_t copy_func = NULL;	// Image copy function
 
 
+  PDFIO_DEBUG("pdfioFileCreateImageObjFromFile(pdf=%p, filename=\"%s\", interpolate=%s)\n", (void *)pdf, filename, interpolate ? "true" : "false");
+
   // Range check input...
   if (!pdf || !filename)
     return (NULL);
@@ -2204,6 +2080,8 @@ pdfioFileCreateImageObjFromFile(
 
   lseek(fd, 0, SEEK_SET);
 
+  PDFIO_DEBUG("pdfioFileCreateImageObjFromFile: buffer=<%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X>\n", buffer[0], buffer[1], buffer[2], buffer[3], buffer[4], buffer[5], buffer[6], buffer[7], buffer[8], buffer[9], buffer[10], buffer[11], buffer[12], buffer[13], buffer[14], buffer[15], buffer[16], buffer[17], buffer[18], buffer[19], buffer[20], buffer[21], buffer[22], buffer[23], buffer[24], buffer[25], buffer[26], buffer[27], buffer[28], buffer[29], buffer[30], buffer[31]);
+
   if (!memcmp(buffer, "\211PNG\015\012\032\012\000\000\000\015IHDR", 16))
   {
     // PNG image...
@@ -2606,8 +2484,198 @@ copy_png(pdfio_dict_t *dict,		// I - Dictionary
          int          fd)		// I - File descriptor
 {
   pdfio_obj_t	*obj = NULL;		// Object
-  pdfio_stream_t *st = NULL;		// Stream for PNG data
+  double	gamma = 2.2,		// Gamma value
+		wx = 0.0, wy = 0.0,	// White point chromacity
+		rx = 0.0, ry = 0.0,	// Red chromacity
+		gx = 0.0, gy = 0.0,	// Green chromacity
+		bx = 0.0, by = 0.0;	// Blue chromacity
+#ifdef HAVE_LIBPNG
+  png_structp	pp = NULL;		// PNG read pointer
+  png_infop	info = NULL;		// PNG info pointers
+  png_bytep	*rows = NULL;		// PNG row pointers
+  unsigned char	*pixels = NULL;		// PNG image data
+  unsigned	i,			// Looping var
+		color_type,		// PNG color mode
+		width,			// Width in columns
+		height,			// Height in lines
+		depth,			// Bit depth
+		num_colors = 0,		// Number of colors
+		linesize;		// Bytes per line
+  bool		alpha;			// Alpha transparency?
+  png_color	*palette;		// Color palette information
+  int		num_palette;		// Number of colors
+  int		num_trans;		// Number of transparent colors
+  png_color_16	*trans;			// Transparent colors
+
+
+  PDFIO_DEBUG("copy_png(dict=%p, fd=%d)\n", (void *)dict, fd);
+
+  // Allocate memory for PNG reader structures...
+  if ((pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, (png_voidp)dict->pdf, png_error_func, png_error_func)) == NULL)
+  {
+    _pdfioFileError(dict->pdf, "Unable to allocate memory for PNG file: %s", strerror(errno));
+    goto finish_png;
+  }
+
+  if ((info = png_create_info_struct(pp)) == NULL)
+  {
+    _pdfioFileError(dict->pdf, "Unable to allocate memory for PNG file: %s", strerror(errno));
+    goto finish_png;
+  }
+
+  PDFIO_DEBUG("copy_png: pp=%p, info=%p\n", (void *)pp, (void *)info);
+
+  if (setjmp(png_jmpbuf(pp)))
+  {
+    // If we get here, PNG loading failed and any errors/warnings were logged
+    // via the corresponding callback functions...
+    fputs("copy_png: setjmp error handler called.\n", stderr);
+    goto finish_png;
+  }
+
+  // Set max image size to 16384x16384...
+  png_set_user_limits(pp, 16384, 16384);
+
+  // Read from the file descriptor...
+  png_set_read_fn(pp, &fd, png_read_func);
+
+  // Don't throw errors with "invalid" sRGB profiles produced by Adobe apps.
+#  if defined(PNG_SKIP_sRGB_CHECK_PROFILE) && defined(PNG_SET_OPTION_SUPPORTED)
+  png_set_option(pp, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
+#  endif // PNG_SKIP_sRGB_CHECK_PROFILE && PNG_SET_OPTION_SUPPORTED
+
+  // Get the image dimensions and depth...
+  png_read_info(pp, info);
+
+  width      = png_get_image_width(pp, info);
+  height     = png_get_image_height(pp, info);
+  depth      = png_get_bit_depth(pp, info);
+  color_type = png_get_color_type(pp, info);
+
+  if (color_type & PNG_COLOR_MASK_PALETTE)
+    num_colors = 1;
+  else if (color_type & PNG_COLOR_MASK_COLOR)
+    num_colors = 3;
+  else
+    num_colors = 1;
+
+  PDFIO_DEBUG("copy_png: width=%u, height=%u, depth=%u, color_type=%u, num_colors=%d\n", width, height, depth, color_type, num_colors);
+
+  // Set decoding options...
+  alpha    = (color_type & PNG_COLOR_MASK_ALPHA) != 0;
+  linesize = (width * num_colors * depth + 7) / 8;
+  if (alpha)
+    linesize += width;
+
+  PDFIO_DEBUG("copy_png: alpha=%s, linesize=%u\n", alpha ? "true" : "false", (unsigned)linesize);
+
+  // Allocate memory for the image...
+  if ((pixels = (unsigned char *)calloc(height, linesize)) == NULL)
+  {
+    _pdfioFileError(dict->pdf, "Unable to allocate memory for PNG image: %s", strerror(errno));
+    goto finish_png;
+  }
+
+  if ((rows = (png_bytep *)calloc((size_t)height, sizeof(png_bytep))) == NULL)
+  {
+    _pdfioFileError(dict->pdf, "Unable to allocate memory for PNG image: %s", strerror(errno));
+    goto finish_png;
+  }
+
+  for (i = 0; i < height; i ++)
+    rows[i] = pixels + i * linesize;
+
+  // Read the image...
+  for (i = png_set_interlace_handling(pp); i > 0; i --)
+    png_read_rows(pp, rows, NULL, (png_uint_32)height);
+
+  // Add image dictionary information...
+  pdfioDictSetNumber(dict, "Width", width);
+  pdfioDictSetNumber(dict, "Height", height);
+  pdfioDictSetNumber(dict, "BitsPerComponent", depth);
+
+  // Grab any color space/palette information...
+  if (png_get_PLTE(pp, info, &palette, &num_palette))
+  {
+    pdfioDictSetArray(dict, "ColorSpace", pdfioArrayCreateColorFromPalette(dict->pdf, num_palette, (unsigned char *)palette));
+  }
+  else if (png_get_cHRM(pp, info, &wx, &wy, &rx, &ry, &gx, &gy, &bx, &by) && png_get_gAMA(pp, info, &gamma))
+  {
+    pdfioDictSetArray(dict, "ColorSpace", pdfioArrayCreateColorFromPrimaries(dict->pdf, num_colors, gamma, wx, wy, rx, ry, gx, gy, bx, by));
+  }
+  else
+  {
+    // Default to sRGB...
+    pdfioDictSetArray(dict, "ColorSpace", pdfioArrayCreateColorFromStandard(dict->pdf, num_colors, PDFIO_CS_SRGB));
+  }
+
+  if (png_get_tRNS(pp, info, /*trans_alpha*/NULL, &num_trans, &trans))
+  {
+    int			m;		// Looping var
+    pdfio_array_t	*mask;		// Mask array
+
+    mask = pdfioArrayCreate(dict->pdf);
+
+    if (color_type & PNG_COLOR_MASK_PALETTE)
+    {
+      // List color indices that are transparent...
+      for (m = 0; m < num_trans; m ++)
+      {
+	pdfioArrayAppendNumber(mask, trans[m].index);
+	pdfioArrayAppendNumber(mask, trans[m].index);
+      }
+    }
+    else if (num_colors == 1)
+    {
+      // List grayscale values that are transparent...
+      for (m = 0; m < num_trans; m ++)
+      {
+	pdfioArrayAppendNumber(mask, trans[m].gray >> (16 - depth));
+	pdfioArrayAppendNumber(mask, trans[m].gray >> (16 - depth));
+      }
+    }
+    else
+    {
+      // List RGB color values that are transparent...
+      for (m = 0; m < num_trans; m ++)
+      {
+	pdfioArrayAppendNumber(mask, trans[m].red >> (16 - depth));
+	pdfioArrayAppendNumber(mask, trans[m].green >> (16 - depth));
+	pdfioArrayAppendNumber(mask, trans[m].blue >> (16 - depth));
+	pdfioArrayAppendNumber(mask, trans[m].red >> (16 - depth));
+	pdfioArrayAppendNumber(mask, trans[m].green >> (16 - depth));
+	pdfioArrayAppendNumber(mask, trans[m].blue >> (16 - depth));
+      }
+    }
+
+    pdfioDictSetArray(dict, "Mask", mask);
+  }
+
+  // Create the image object...
+  obj = create_image(dict, pixels, width, height, depth, num_colors, alpha);
+
+  finish_png:
+
+  if (pp && info)
+  {
+    png_read_end(pp, info);
+    png_destroy_read_struct(&pp, &info, NULL);
+
+    pp   = NULL;
+    info = NULL;
+  }
+
+  free(pixels);
+  pixels = NULL;
+
+  free(rows);
+  rows = NULL;
+
+  return (obj);
+
+#else
   pdfio_dict_t	*decode = NULL;		// Parameters for PNG decode
+  pdfio_stream_t *st = NULL;		// Stream for PNG data
   ssize_t	bytes;			// Bytes read
   unsigned char	buffer[16384];		// Read buffer
   unsigned	i,			// Looping var
@@ -2616,14 +2684,11 @@ copy_png(pdfio_dict_t *dict,		// I - Dictionary
 		crc,			// CRC-32
 		temp,			// Temporary value
 		width = 0,		// Width
-		height = 0;		// Height
+		height = 0,		// Height
+		num_colors = 0;		// Number of colors
   unsigned char	bit_depth = 0,		// Bit depth
-		color_type = 0;		// Color type
-  double	gamma = 2.2,		// Gamma value
-		wx = 0.0, wy = 0.0,	// White point chromacity
-		rx = 0.0, ry = 0.0,	// Red chromacity
-		gx = 0.0, gy = 0.0,	// Green chromacity
-		bx = 0.0, by = 0.0;	// Blue chromacity
+		color_type = 0,		// Color type
+		interlace = 0;		// Interlace type
   pdfio_array_t	*mask = NULL;		// Color masking array
 
 
@@ -2730,15 +2795,52 @@ copy_png(pdfio_dict_t *dict,		// I - Dictionary
 	  crc    = update_png_crc(crc, buffer, length);
 	  width  = (unsigned)((buffer[0] << 24) | (buffer[1] << 16) | (buffer[2] << 8) | buffer[3]);
 	  height = (unsigned)((buffer[4] << 24) | (buffer[5] << 16) | (buffer[6] << 8) | buffer[7]);
+
+	  if (width == 0 || height == 0)
+	  {
+	    _pdfioFileError(dict->pdf, "Unsupported PNG dimensions %ux%u.", (unsigned)width, (unsigned)height);
+	    return (NULL);
+	  }
+
 	  bit_depth = buffer[8];
 	  color_type = buffer[9];
 
-	  if (width == 0 || height == 0 || (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 && bit_depth != 8 && bit_depth != 16) || (color_type != _PDFIO_PNG_TYPE_GRAY && color_type != _PDFIO_PNG_TYPE_RGB && color_type != _PDFIO_PNG_TYPE_INDEXED) || buffer[10] || buffer[11] || buffer[12])
+	  if (color_type != _PDFIO_PNG_TYPE_GRAY && color_type != _PDFIO_PNG_TYPE_RGB && color_type != _PDFIO_PNG_TYPE_INDEXED)
 	  {
-	    _pdfioFileError(dict->pdf, "Unsupported PNG image.");
+	    _pdfioFileError(dict->pdf, "Unsupported PNG color type %u.", color_type);
 	    return (NULL);
 	  }
 
+	  if ((color_type == _PDFIO_PNG_TYPE_GRAY && bit_depth != 1 && bit_depth != 2 && bit_depth != 4 && bit_depth != 8 && bit_depth != 16) ||
+	      (color_type == _PDFIO_PNG_TYPE_RGB && bit_depth != 8 && bit_depth != 16) ||
+	      (color_type == _PDFIO_PNG_TYPE_INDEXED && bit_depth != 1 && bit_depth != 2 && bit_depth != 4 && bit_depth != 8))
+	  {
+	    _pdfioFileError(dict->pdf, "Unsupported PNG bit depth %u for color type %u.", bit_depth, color_type);
+	    return (NULL);
+	  }
+
+	  if (buffer[10] != _PDFIO_PNG_COMPRESSION_FLATE)
+	  {
+	    _pdfioFileError(dict->pdf, "Unsupported PNG compression %u.", buffer[10]);
+	    return (NULL);
+	  }
+
+	  if (buffer[11] != _PDFIO_PNG_FILTER_ADAPTIVE)
+	  {
+	    _pdfioFileError(dict->pdf, "Unsupported PNG filtering %u.", buffer[11]);
+	    return (NULL);
+	  }
+
+          interlace = buffer[12];
+
+	  if (interlace != _PDFIO_PNG_INTERLACE_NONE)
+	  {
+	    _pdfioFileError(dict->pdf, "Unsupported PNG interlacing %u.", interlace);
+	    return (NULL);
+	  }
+
+          num_colors = color_type == _PDFIO_PNG_TYPE_RGB ? 3 : 1;
+
 	  pdfioDictSetNumber(dict, "Width", width);
 	  pdfioDictSetNumber(dict, "Height", height);
 	  pdfioDictSetNumber(dict, "BitsPerComponent", bit_depth);
@@ -2748,7 +2850,7 @@ copy_png(pdfio_dict_t *dict,		// I - Dictionary
 	    return (NULL);
 
 	  pdfioDictSetNumber(decode, "BitsPerComponent", bit_depth);
-	  pdfioDictSetNumber(decode, "Colors", color_type == _PDFIO_PNG_TYPE_RGB ? 3 : 1);
+	  pdfioDictSetNumber(decode, "Colors", num_colors);
 	  pdfioDictSetNumber(decode, "Columns", width);
 	  pdfioDictSetNumber(decode, "Predictor", _PDFIO_PREDICTOR_PNG_AUTO);
 	  pdfioDictSetDict(dict, "DecodeParms", decode);
@@ -2948,6 +3050,7 @@ copy_png(pdfio_dict_t *dict,		// I - Dictionary
   }
 
   return (NULL);
+#endif // HAVE_LIBPNG
 }
 
 
@@ -3227,6 +3330,210 @@ create_cp1252(pdfio_file_t *pdf)	// I - PDF file
 }
 
 
+//
+// 'create_image()' - Create an image object from some data.
+//
+
+static pdfio_obj_t *			// O - PDF object or `NULL` on error
+create_image(
+    pdfio_dict_t        *dict,		// I - Image dictionary
+    const unsigned char *data,		// I - Image data
+    size_t              width,		// I - Width in columns
+    size_t              height,		// I - Height in lines
+    size_t              depth,		// I - Bit depth
+    size_t              num_colors,	// I - Number of colors
+    bool                alpha)		// I - `true` if there is transparency
+{
+  pdfio_file_t		*pdf = dict->pdf;
+					// PDF file
+  pdfio_dict_t		*mask_dict,	// Mask image dictionary
+			*decode;	// DecodeParms dictionary
+  pdfio_obj_t		*obj,		// Image object
+			*mask_obj = NULL;
+					// Mask image object, if any
+  pdfio_stream_t	*st;		// Image stream
+  size_t		x, y,		// X and Y position in image
+			bpc = depth / 8,// Bytes per component
+			bpp = num_colors * bpc,
+					// Bytes per pixel (less alpha)
+			linelen;	// Line length
+  const unsigned char	*dataptr;	// Pointer into image data
+  unsigned char		*line = NULL,	// Current line
+			*lineptr;	// Pointer into line
+
+
+  // Allocate memory for one line of data...
+  linelen = (width * num_colors * depth + 7) / 8;
+
+  if ((line = malloc(linelen)) == NULL)
+    return (NULL);
+
+  // Use Flate compression...
+  pdfioDictSetName(dict, "Filter", "FlateDecode");
+
+  // Generate a mask image, as needed...
+  if (alpha)
+  {
+    // Create the image mask dictionary...
+    if ((mask_dict = pdfioDictCopy(pdf, dict)) == NULL)
+    {
+      free(line);
+      return (NULL);
+    }
+
+    // Transparency masks are always grayscale...
+    pdfioDictSetName(mask_dict, "ColorSpace", "DeviceGray");
+
+    // Set the automatic PNG predictor to optimize compression...
+    if ((decode = pdfioDictCreate(pdf)) == NULL)
+    {
+      free(line);
+      return (NULL);
+    }
+
+    pdfioDictSetNumber(decode, "BitsPerComponent", depth);
+    pdfioDictSetNumber(decode, "Colors", 1);
+    pdfioDictSetNumber(decode, "Columns", width);
+    pdfioDictSetNumber(decode, "Predictor", _PDFIO_PREDICTOR_PNG_AUTO);
+    pdfioDictSetDict(mask_dict, "DecodeParms", decode);
+
+    // Create the mask object and write the mask image...
+    if ((mask_obj = pdfioFileCreateObj(pdf, mask_dict)) == NULL)
+    {
+      free(line);
+      return (NULL);
+    }
+
+    if ((st = pdfioObjCreateStream(mask_obj, PDFIO_FILTER_FLATE)) == NULL)
+    {
+      free(line);
+      pdfioObjClose(mask_obj);
+      return (NULL);
+    }
+
+    for (y = height, dataptr = data + bpp; y > 0; y --)
+    {
+      if (bpc == 1)
+      {
+	for (x = width, lineptr = line; x > 0; x --, dataptr += bpp)
+	  *lineptr++ = *dataptr++;
+      }
+      else
+      {
+	for (x = width, lineptr = line; x > 0; x --, dataptr += bpp)
+	{
+	  *lineptr++ = *dataptr++;
+	  *lineptr++ = *dataptr++;
+	}
+      }
+
+      pdfioStreamWrite(st, line, width * bpc);
+    }
+
+    pdfioStreamClose(st);
+
+    // Use the transparency mask...
+    pdfioDictSetObj(dict, "SMask", mask_obj);
+  }
+
+  // Set the automatic PNG predictor to optimize compression...
+  if ((decode = pdfioDictCreate(pdf)) == NULL)
+  {
+    free(line);
+    return (NULL);
+  }
+
+  pdfioDictSetNumber(decode, "BitsPerComponent", depth);
+  pdfioDictSetNumber(decode, "Colors", num_colors);
+  pdfioDictSetNumber(decode, "Columns", width);
+  pdfioDictSetNumber(decode, "Predictor", _PDFIO_PREDICTOR_PNG_AUTO);
+  pdfioDictSetDict(dict, "DecodeParms", decode);
+
+  // Now create the image...
+  if ((obj = pdfioFileCreateObj(pdf, dict)) == NULL)
+  {
+    free(line);
+    return (NULL);
+  }
+
+  if ((st = pdfioObjCreateStream(obj, PDFIO_FILTER_FLATE)) == NULL)
+  {
+    free(line);
+    pdfioObjClose(obj);
+    return (NULL);
+  }
+
+  for (y = height, dataptr = data; y > 0; y --)
+  {
+    if (alpha)
+    {
+      if (bpp == 1)
+      {
+	for (x = width, lineptr = line; x > 0; x --, dataptr += bpc)
+	  *lineptr++ = *dataptr++;
+      }
+      else
+      {
+	for (x = width, lineptr = line; x > 0; x --, dataptr += bpp + bpc, lineptr += bpp)
+	  memcpy(lineptr, dataptr, bpp);
+      }
+
+      pdfioStreamWrite(st, line, linelen);
+    }
+    else
+    {
+      pdfioStreamWrite(st, dataptr, linelen);
+      dataptr += linelen;
+    }
+  }
+
+  free(line);
+  pdfioStreamClose(st);
+
+  return (obj);
+}
+
+
+#ifdef HAVE_LIBPNG
+//
+// 'png_error_func()' - PNG error message function.
+//
+
+static void
+png_error_func(
+    png_structp     pp,			// I - PNG pointer
+    png_const_charp message)		// I - Error message
+{
+  pdfio_file_t	*pdf = (pdfio_file_t *)png_get_error_ptr(pp);
+					// PDF file
+
+
+  _pdfioFileError(pdf, "Unable to create image object from PNG file: %s", message);
+}
+
+
+//
+// 'png_read_func()' - Read from a PNG file.
+//
+
+static void
+png_read_func(png_structp pp,		// I - PNG pointer
+              png_bytep   data,		// I - Read buffer
+              size_t      length)	// I - Number of bytes to read
+{
+  int		*fd = (int *)png_get_io_ptr(pp);
+					// Pointer to file descriptor
+  ssize_t	bytes;			// Bytes read
+
+
+  PDFIO_DEBUG("png_read_func(pp=%p, data=%p, length=%lu)\n", (void *)pp, (void *)data, (unsigned long)length);
+
+  if ((bytes = read(*fd, data, length)) < (ssize_t)length)
+    png_error(pp, "Unable to read from PNG file.");
+}
+#endif // HAVE_LIBPNG
+
+
 //
 // 'ttf_error_cb()' - Relay a message from the TTF functions.
 //
@@ -3239,6 +3546,7 @@ ttf_error_cb(pdfio_file_t *pdf,		// I - PDF file
 }
 
 
+#ifndef HAVE_LIBPNG
 //
 // 'update_png_crc()' - Update the CRC-32 value for a PNG chunk.
 //
@@ -3258,6 +3566,7 @@ update_png_crc(
 
   return (crc);
 }
+#endif // !HAVE_LIBPNG
 
 
 //

pdfio-file.c

@@ -801,6 +801,18 @@ pdfioFileGetKeywords(pdfio_file_t *pdf)	// I - PDF file
 }
 
 
+//
+// 'pdfioFileGetModDate()' - Get the most recent modification date for a PDF file.
+//
+
+time_t					// O - Modification date or `0` for none
+pdfioFileGetModDate(
+    pdfio_file_t *pdf)			// I - PDF file
+{
+  return (pdf && pdf->info_obj ? pdfioDictGetDate(pdfioObjGetDict(pdf->info_obj), "ModDate") : 0);
+}
+
+
 //
 // 'pdfioFileGetName()' - Get a PDF's filename.
 //

pdfio.h

@@ -201,6 +201,7 @@ extern time_t		pdfioFileGetCreationDate(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern const char	*pdfioFileGetCreator(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern pdfio_array_t	*pdfioFileGetID(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern const char	*pdfioFileGetKeywords(pdfio_file_t *pdf) _PDFIO_PUBLIC;
+extern time_t		pdfioFileGetModDate(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern const char	*pdfioFileGetName(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern size_t		pdfioFileGetNumObjs(pdfio_file_t *pdf) _PDFIO_PUBLIC;
 extern size_t		pdfioFileGetNumPages(pdfio_file_t *pdf) _PDFIO_PUBLIC;

pdfio.vcxproj

@@ -172,6 +172,8 @@
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
+    <Import Project="packages\libpng_native.redist.1.6.30\build\native\libpng_native.redist.targets" Condition="Exists('packages\libpng_native.redist.1.6.30\build\native\libpng_native.redist.targets')" />
+    <Import Project="packages\libpng_native.1.6.30\build\native\libpng_native.targets" Condition="Exists('packages\libpng_native.1.6.30\build\native\libpng_native.targets')" />
     <Import Project="packages\zlib_native.redist.1.2.11\build\native\zlib_native.redist.targets" Condition="Exists('packages\zlib_native.redist.1.2.11\build\native\zlib_native.redist.targets')" />
     <Import Project="packages\zlib_native.1.2.11\build\native\zlib_native.targets" Condition="Exists('packages\zlib_native.1.2.11\build\native\zlib_native.targets')" />
   </ImportGroup>

pdfio1.def

@@ -204,6 +204,7 @@ pdfioFileGetCreationDate
 pdfioFileGetCreator
 pdfioFileGetID
 pdfioFileGetKeywords
+pdfioFileGetModDate
 pdfioFileGetName
 pdfioFileGetNumObjs
 pdfioFileGetNumPages

pdfio_native.nuspec

@@ -3,7 +3,7 @@
     <metadata>
         <id>pdfio_native</id>
         <title>PDFio Library for VS2019+</title>
-        <version>1.4.1</version>
+        <version>1.5.0</version>
         <authors>Michael R Sweet</authors>
         <owners>michaelrsweet</owners>
         <projectUrl>https://github.com/michaelrsweet/pappl</projectUrl>
@@ -16,7 +16,7 @@
         <copyright>Copyright © 2019-2025 by Michael R Sweet</copyright>
         <tags>pdf file native</tags>
 	<dependencies>
-	    <dependency id="pdfio_native.redist" version="1.4.1" />
+	    <dependency id="pdfio_native.redist" version="1.5.0" />
 	    <dependency id="zlib_native.redist" version="1.2.11" />
 	</dependencies>
     </metadata>

pdfio_native.redist.nuspec

@@ -3,7 +3,7 @@
     <metadata>
         <id>pdfio_native.redist</id>
         <title>PDFio Library for VS2019+</title>
-        <version>1.4.1</version>
+        <version>1.5.0</version>
         <authors>Michael R Sweet</authors>
         <owners>michaelrsweet</owners>
         <projectUrl>https://github.com/michaelrsweet/pappl</projectUrl>

testfiles/pngsuite-LICENSE.txt

@@ -0,0 +1,9 @@
+PngSuite
+--------
+
+Permission to use, copy, modify and distribute these images for any
+purpose and without fee is hereby granted.
+
+
+(c) Willem van Schaik, 1996, 2011
+

testpdfio.c

@@ -47,7 +47,7 @@ static int	write_header_footer(pdfio_stream_t *st, const char *title, int number
 static pdfio_obj_t *write_image_object(pdfio_file_t *pdf, _pdfio_predictor_t predictor);
 static int	write_images_test(pdfio_file_t *pdf, int number, pdfio_obj_t *font);
 static int	write_jpeg_test(pdfio_file_t *pdf, const char *title, int number, pdfio_obj_t *font, pdfio_obj_t *image);
-static int	write_png_test(pdfio_file_t *pdf, int number, pdfio_obj_t *font);
+static int	write_png_tests(pdfio_file_t *pdf, int number, pdfio_obj_t *font);
 static int	write_text_test(pdfio_file_t *pdf, int first_page, pdfio_obj_t *font, const char *filename);
 static int	write_unit_file(pdfio_file_t *inpdf, const char *outname, pdfio_file_t *outpdf, size_t *num_pages, size_t *first_image);
 
@@ -2989,11 +2989,11 @@ write_jpeg_test(pdfio_file_t *pdf,	// I - PDF file
 
 
 //
-// 'write_png_test()' - Write a page of PNG test images.
+// 'write_png_tests()' - Write pages of PNG test images.
 //
 
 static int				// O - 0 on success, 1 on failure
-write_png_test(pdfio_file_t *pdf,		// I - PDF file
+write_png_tests(pdfio_file_t *pdf,	// I - PDF file
 	        int          number,	// I - Page number
 	        pdfio_obj_t  *font)	// I - Page number font
 {
@@ -3002,6 +3002,71 @@ write_png_test(pdfio_file_t *pdf,		// I - PDF file
   pdfio_obj_t		*color,		// pdfio-color.png
 			*gray,		// pdfio-gray.png
 			*indexed;	// pdfio-indexed.png
+#ifdef HAVE_LIBPNG
+  size_t		i;		// Looping var
+  char			imgname[32];	// Image name
+  pdfio_obj_t		*pngsuite[80];	// PngSuite test file objects
+  static const char * const pngsuite_files[80] =
+  {					// PngSuite test filenames
+    "testfiles/pngsuite/basi0g01.png", "testfiles/pngsuite/basi0g02.png",
+    "testfiles/pngsuite/basi0g04.png", "testfiles/pngsuite/basi0g08.png",
+    "testfiles/pngsuite/basi2c08.png", "testfiles/pngsuite/basi3p01.png",
+    "testfiles/pngsuite/basi3p02.png", "testfiles/pngsuite/basi3p04.png",
+    "testfiles/pngsuite/basi3p08.png", "testfiles/pngsuite/basi4a08.png",
+    "testfiles/pngsuite/basi6a08.png", "testfiles/pngsuite/basn0g01.png",
+    "testfiles/pngsuite/basn0g02.png", "testfiles/pngsuite/basn0g04.png",
+    "testfiles/pngsuite/basn0g08.png", "testfiles/pngsuite/basn2c08.png",
+    "testfiles/pngsuite/basn3p01.png", "testfiles/pngsuite/basn3p02.png",
+    "testfiles/pngsuite/basn3p04.png", "testfiles/pngsuite/basn3p08.png",
+    "testfiles/pngsuite/basn4a08.png", "testfiles/pngsuite/basn6a08.png",
+    "testfiles/pngsuite/exif2c08.png", "testfiles/pngsuite/g03n2c08.png",
+    "testfiles/pngsuite/g03n3p04.png", "testfiles/pngsuite/g04n2c08.png",
+    "testfiles/pngsuite/g04n3p04.png", "testfiles/pngsuite/g05n2c08.png",
+    "testfiles/pngsuite/g05n3p04.png", "testfiles/pngsuite/g07n2c08.png",
+    "testfiles/pngsuite/g07n3p04.png", "testfiles/pngsuite/g10n2c08.png",
+    "testfiles/pngsuite/g10n3p04.png", "testfiles/pngsuite/g25n2c08.png",
+    "testfiles/pngsuite/g25n3p04.png", "testfiles/pngsuite/s02i3p01.png",
+    "testfiles/pngsuite/s02n3p01.png", "testfiles/pngsuite/s03i3p01.png",
+    "testfiles/pngsuite/s03n3p01.png", "testfiles/pngsuite/s04i3p01.png",
+    "testfiles/pngsuite/s04n3p01.png", "testfiles/pngsuite/s05i3p02.png",
+    "testfiles/pngsuite/s05n3p02.png", "testfiles/pngsuite/s06i3p02.png",
+    "testfiles/pngsuite/s06n3p02.png", "testfiles/pngsuite/s07i3p02.png",
+    "testfiles/pngsuite/s07n3p02.png", "testfiles/pngsuite/s08i3p02.png",
+    "testfiles/pngsuite/s08n3p02.png", "testfiles/pngsuite/s09i3p02.png",
+    "testfiles/pngsuite/s09n3p02.png", "testfiles/pngsuite/s32i3p04.png",
+    "testfiles/pngsuite/s32n3p04.png", "testfiles/pngsuite/s33i3p04.png",
+    "testfiles/pngsuite/s33n3p04.png", "testfiles/pngsuite/s34i3p04.png",
+    "testfiles/pngsuite/s34n3p04.png", "testfiles/pngsuite/s35i3p04.png",
+    "testfiles/pngsuite/s35n3p04.png", "testfiles/pngsuite/s36i3p04.png",
+    "testfiles/pngsuite/s36n3p04.png", "testfiles/pngsuite/s37i3p04.png",
+    "testfiles/pngsuite/s37n3p04.png", "testfiles/pngsuite/s38i3p04.png",
+    "testfiles/pngsuite/s38n3p04.png", "testfiles/pngsuite/s39i3p04.png",
+    "testfiles/pngsuite/s39n3p04.png", "testfiles/pngsuite/s40i3p04.png",
+    "testfiles/pngsuite/s40n3p04.png", "testfiles/pngsuite/tbbn0g04.png",
+    "testfiles/pngsuite/tbbn3p08.png", "testfiles/pngsuite/tbgn3p08.png",
+    "testfiles/pngsuite/tbrn2c08.png", "testfiles/pngsuite/tbwn3p08.png",
+    "testfiles/pngsuite/tbyn3p08.png", "testfiles/pngsuite/tm3n3p02.png",
+    "testfiles/pngsuite/tp0n0g08.png", "testfiles/pngsuite/tp0n2c08.png",
+    "testfiles/pngsuite/tp0n3p08.png", "testfiles/pngsuite/tp1n3p08.png"
+  };
+  static const char * const pngsuite_labels[80] =
+  {					// PngSuite test labels
+    "basi0g01", "basi0g02", "basi0g04", "basi0g08", "basi2c08", "basi3p01",
+    "basi3p02", "basi3p04", "basi3p08", "basi4a08", "basi6a08", "basn0g01",
+    "basn0g02", "basn0g04", "basn0g08", "basn2c08", "basn3p01", "basn3p02",
+    "basn3p04", "basn3p08", "basn4a08", "basn6a08", "exif2c08", "g03n2c08",
+    "g03n3p04", "g04n2c08", "g04n3p04", "g05n2c08", "g05n3p04", "g07n2c08",
+    "g07n3p04", "g10n2c08", "g10n3p04", "g25n2c08", "g25n3p04", "s02i3p01",
+    "s02n3p01", "s03i3p01", "s03n3p01", "s04i3p01", "s04n3p01", "s05i3p02",
+    "s05n3p02", "s06i3p02", "s06n3p02", "s07i3p02", "s07n3p02", "s08i3p02",
+    "s08n3p02", "s09i3p02", "s09n3p02", "s32i3p04", "s32n3p04", "s33i3p04",
+    "s33n3p04", "s34i3p04", "s34n3p04", "s35i3p04", "s35n3p04", "s36i3p04",
+    "s36n3p04", "s37i3p04", "s37n3p04", "s38i3p04", "s38n3p04", "s39i3p04",
+    "s39n3p04", "s40i3p04", "s40n3p04", "tbbn0g04", "tbbn3p08", "tbgn3p08",
+    "tbrn2c08", "tbwn3p08", "tbyn3p08", "tm3n3p02", "tp0n0g08", "tp0n2c08",
+    "tp0n3p08", "tp1n3p08"
+  };
+#endif // HAVE_LIBPNG
 
 
   // Import the PNG test images
@@ -3023,6 +3088,7 @@ write_png_test(pdfio_file_t *pdf,		// I - PDF file
   else
     return (1);
 
+  ////// PDFio PNG image test page...
   // Create the page dictionary, object, and stream...
   fputs("pdfioDictCreate: ", stdout);
   if ((dict = pdfioDictCreate(pdf)) != NULL)
@@ -3168,6 +3234,109 @@ write_png_test(pdfio_file_t *pdf,		// I - PDF file
   else
     return (1);
 
+#ifdef HAVE_LIBPNG
+  ////// PngSuite page
+  // Create the image objects...
+  for (i = 0; i < (sizeof(pngsuite_files) / sizeof(pngsuite_files[0])); i ++)
+  {
+    fprintf(stdout, "pdfioFileCreateImageObjFromFile(\"%s\"): ", pngsuite_files[i]);
+    if ((pngsuite[i] = pdfioFileCreateImageObjFromFile(pdf, pngsuite_files[i], false)) != NULL)
+      puts("PASS");
+    else
+      return (1);
+  }
+
+  // Create the page dictionary, object, and stream...
+  fputs("pdfioDictCreate: ", stdout);
+  if ((dict = pdfioDictCreate(pdf)) != NULL)
+    puts("PASS");
+  else
+    return (1);
+
+  for (i = 0; i < (sizeof(pngsuite_files) / sizeof(pngsuite_files[0])); i ++)
+  {
+    fprintf(stdout, "pdfioPageDictAddImage(\"%s\"): ", pngsuite_labels[i]);
+    snprintf(imgname, sizeof(imgname), "IM%u", (unsigned)(i + 1));
+    if (pdfioPageDictAddImage(dict, pdfioStringCreate(pdf, imgname), pngsuite[i]))
+      puts("PASS");
+    else
+      return (1);
+  }
+
+  fputs("pdfioPageDictAddFont(F1): ", stdout);
+  if (pdfioPageDictAddFont(dict, "F1", font))
+    puts("PASS");
+  else
+    return (1);
+
+  printf("pdfioFileCreatePage(%d): ", number + 1);
+
+  if ((st = pdfioFileCreatePage(pdf, dict)) != NULL)
+    puts("PASS");
+  else
+    return (1);
+
+  if (write_header_footer(st, "PngSuite Test Page", number + 1))
+    goto error;
+
+  // Show content...
+  fputs("pdfioContentSetTextFont(\"F1\", 9.0): ", stdout);
+  if (pdfioContentSetTextFont(st, "F1", 8.0))
+    puts("PASS");
+  else
+    goto error;
+
+  for (i = 0; i < (sizeof(pngsuite_files) / sizeof(pngsuite_files[0])); i ++)
+  {
+    double x = (i % 8) * 69.0 + 36;	// X position
+    double y = 671 - (i / 8) * 64.0;	// Y position
+
+    fputs("pdfioContentTextBegin(): ", stdout);
+    if (pdfioContentTextBegin(st))
+      puts("PASS");
+    else
+      goto error;
+
+    printf("pdfioContentTextMoveTo(%g, %g): ", x, y);
+    if (pdfioContentTextMoveTo(st, x, y))
+      puts("PASS");
+    else
+      goto error;
+
+    printf("pdfioContentTextShow(\"%s\"): ", pngsuite_labels[i]);
+    if (pdfioContentTextShow(st, false, pngsuite_labels[i]))
+      puts("PASS");
+    else
+      goto error;
+
+    fputs("pdfioContentTextEnd(): ", stdout);
+    if (pdfioContentTextEnd(st))
+      puts("PASS");
+    else
+      goto error;
+  }
+
+  for (i = 0; i < (sizeof(pngsuite_files) / sizeof(pngsuite_files[0])); i ++)
+  {
+    double x = (i % 8) * 69.0 + 36;	// X position
+    double y = 671 - (i / 8) * 64.0;	// Y position
+
+    snprintf(imgname, sizeof(imgname), "IM%u", (unsigned)(i + 1));
+    printf("pdfioContentDrawImage(\"%s\"): ", imgname);
+    if (pdfioContentDrawImage(st, imgname, x, y + 9, 32, 32))
+      puts("PASS");
+    else
+      goto error;
+  }
+
+  // Close the object and stream...
+  fputs("pdfioStreamClose: ", stdout);
+  if (pdfioStreamClose(st))
+    puts("PASS");
+  else
+    return (1);
+#endif // HAVE_LIBPNG
+
   return (0);
 
   error:
@@ -3367,6 +3536,7 @@ write_unit_file(
 			*gray_jpg,	// gray.jpg image
 			*helvetica,	// Helvetica font
 			*page;		// Page from test PDF file
+  int			pagenum = 1;	// Current page number
   pdfio_dict_t		*catalog;	// Catalog dictionary
 
 
@@ -3506,10 +3676,14 @@ write_unit_file(
   else
     return (1);
 
+  pagenum ++;
+
   // Write a page with a color image...
-  if (write_jpeg_test(outpdf, "Color JPEG Test", 2, helvetica, color_jpg))
+  if (write_jpeg_test(outpdf, "Color JPEG Test", pagenum, helvetica, color_jpg))
     return (1);
 
+  pagenum ++;
+
   // Copy the third page from the test PDF file...
   fputs("pdfioFileGetPage(2): ", stdout);
   if ((page = pdfioFileGetPage(inpdf, 2)) != NULL)
@@ -3523,39 +3697,60 @@ write_unit_file(
   else
     return (1);
 
+  pagenum ++;
+
   // Write a page with a grayscale image...
-  if (write_jpeg_test(outpdf, "Grayscale JPEG Test", 4, helvetica, gray_jpg))
+  if (write_jpeg_test(outpdf, "Grayscale JPEG Test", pagenum, helvetica, gray_jpg))
     return (1);
+  pagenum ++;
 
   // Write a page with PNG images...
-  if (write_png_test(outpdf, 5, helvetica))
+  if (write_png_tests(outpdf, pagenum, helvetica))
     return (1);
 
+#ifdef HAVE_LIBPNG
+  pagenum += 2;
+#else
+  pagenum ++;
+#endif // HAVE_LIBPNG
+
   // Write a page that tests multiple color spaces...
-  if (write_color_test(outpdf, 6, helvetica))
+  if (write_color_test(outpdf, pagenum, helvetica))
     return (1);
 
+  pagenum ++;
+
   // Write a page with test images...
   *first_image = pdfioFileGetNumObjs(outpdf) + 1;
-  if (write_images_test(outpdf, 7, helvetica))
+  if (write_images_test(outpdf, pagenum, helvetica))
     return (1);
 
+  pagenum ++;
+
   // Write a page width alpha (soft masks)...
-  if (write_alpha_test(outpdf, 8, helvetica))
+  if (write_alpha_test(outpdf, pagenum, helvetica))
     return (1);
 
+  pagenum ++;
+
   // Test TrueType fonts...
-  if (write_font_test(outpdf, 9, helvetica, "testfiles/OpenSans-Regular.ttf", false))
+  if (write_font_test(outpdf, pagenum, helvetica, "testfiles/OpenSans-Regular.ttf", false))
     return (1);
 
-  if (write_font_test(outpdf, 10, helvetica, "testfiles/OpenSans-Regular.ttf", true))
+  pagenum ++;
+
+  if (write_font_test(outpdf, pagenum, helvetica, "testfiles/OpenSans-Regular.ttf", true))
     return (1);
 
-  if (write_font_test(outpdf, 11, helvetica, "testfiles/NotoSansJP-Regular.otf", true))
+  pagenum ++;
+
+  if (write_font_test(outpdf, pagenum, helvetica, "testfiles/NotoSansJP-Regular.otf", true))
     return (1);
 
+  pagenum ++;
+
   // Print this text file...
-  if (write_text_test(outpdf, 12, helvetica, "README.md"))
+  if (write_text_test(outpdf, pagenum, helvetica, "README.md"))
     return (1);
 
   fputs("pdfioFileGetNumPages: ", stdout);