source/libs/poppler/poppler-src/goo/JpegWriter.cc

   1 //========================================================================
   2 //
   3 // JpegWriter.cc
   4 //
   5 // This file is licensed under the GPLv2 or later
   6 //
   7 // Copyright (C) 2009 Stefan Thomas <thomas@eload24.com>
   8 // Copyright (C) 2010, 2012 Adrian Johnson <ajohnson@redneon.com>
   9 // Copyright (C) 2010 Harry Roberts <harry.roberts@midnight-labs.org>
  10 // Copyright (C) 2011 Thomas Freitag <Thomas.Freitag@alfa.de>
  11 // Copyright (C) 2013 Peter Breitenlohner <peb@mppmu.mpg.de>
  12 //
  13 //========================================================================
  14
  15 #include "JpegWriter.h"
  16
  17 #ifdef ENABLE_LIBJPEG
  18
  19 extern "C" {
  20 #include <jpeglib.h>
  21 }
  22
  23 #include "poppler/Error.h"
  24
  25 struct JpegWriterPrivate {
  26   bool progressive;
  27   int quality;
  28   JpegWriter::Format format;
  29   struct jpeg_compress_struct cinfo;
  30   struct jpeg_error_mgr jerr;
  31 };
  32
  33 void outputMessage(j_common_ptr cinfo)
  34 {
  35   char buffer[JMSG_LENGTH_MAX];
  36
  37   // Create the message
  38   (*cinfo->err->format_message) (cinfo, buffer);
  39
  40   // Send it to poppler's error handler
  41   error(errInternal, -1, "{0:s}", buffer);
  42 }
  43
  44 JpegWriter::JpegWriter(int q, bool p, Format formatA)
  45 {
  46   priv = new JpegWriterPrivate;
  47   priv->progressive = p;
  48   priv->quality = q;
  49   priv->format = formatA;
  50 }
  51
  52 JpegWriter::JpegWriter(Format formatA)
  53 {
  54   priv = new JpegWriterPrivate;
  55   priv->progressive = false;
  56   priv->quality = -1;
  57   priv->format = formatA;
  58 }
  59
  60 JpegWriter::~JpegWriter()
  61 {
  62   // cleanup
  63   jpeg_destroy_compress(&priv->cinfo);
  64   delete priv;
  65 }
  66
  67 bool JpegWriter::init(FILE *f, int width, int height, int hDPI, int vDPI)
  68 {
  69   // Setup error handler
  70   priv->cinfo.err = jpeg_std_error(&priv->jerr);
  71   priv->jerr.output_message = &outputMessage;
  72
  73   // Initialize libjpeg
  74   jpeg_create_compress(&priv->cinfo);
  75
  76   // First set colorspace and call jpeg_set_defaults() since
  77   // jpeg_set_defaults() sets default values for all fields in
  78   // cinfo based on the colorspace.
  79   switch (priv->format) {
  80     case RGB:
  81       priv->cinfo.in_color_space = JCS_RGB;
  82       break;
  83     case GRAY:
  84       priv->cinfo.in_color_space = JCS_GRAYSCALE;
  85       break;
  86     case CMYK:
  87       priv->cinfo.in_color_space = JCS_CMYK;
  88       break;
  89     default:
  90       return false;
  91   }
  92   jpeg_set_defaults(&priv->cinfo);
  93
  94   // Set destination file
  95   jpeg_stdio_dest(&priv->cinfo, f);
  96
  97   // Set libjpeg configuration
  98   priv->cinfo.image_width = width;
  99   priv->cinfo.image_height = height;
 100   priv->cinfo.density_unit = 1; // dots per inch
 101   priv->cinfo.X_density = hDPI;
 102   priv->cinfo.Y_density = vDPI;
 103   switch (priv->format) {
 104     case GRAY:
 105       priv->cinfo.input_components = 1;
 106       break;
 107     case RGB:
 108       priv->cinfo.input_components = 3;
 109       break;
 110     case CMYK:
 111       priv->cinfo.input_components = 4;
 112       jpeg_set_colorspace(&priv->cinfo, JCS_YCCK);
 113       priv->cinfo.write_JFIF_header = TRUE;
 114       break;
 115     default:
 116       return false;
 117   }
 118
 119   // Set quality
 120   if (priv->quality >= 0 && priv->quality <= 100) {
 121     jpeg_set_quality(&priv->cinfo, priv->quality, TRUE);
 122   }
 123
 124   // Use progressive mode
 125   if (priv->progressive) {
 126     jpeg_simple_progression(&priv->cinfo);
 127   }
 128
 129   // Get ready for data
 130   jpeg_start_compress(&priv->cinfo, TRUE);
 131
 132   return true;
 133 }
 134
 135 bool JpegWriter::writePointers(unsigned char **rowPointers, int rowCount)
 136 {
 137   if (priv->format == CMYK) {
 138     for (int y = 0; y < rowCount; y++) {
 139       unsigned char *row = rowPointers[y];
 140       for (unsigned int x = 0; x < priv->cinfo.image_width; x++) {
 141         for (int n = 0; n < 4; n++) {
 142           *row = 0xff - *row;
 143           row++;
 144         }
 145       }
 146     }
 147   }
 148   // Write all rows to the file
 149   jpeg_write_scanlines(&priv->cinfo, rowPointers, rowCount);
 150
 151   return true;
 152 }
 153
 154 bool JpegWriter::writeRow(unsigned char **rowPointer)
 155 {
 156   if (priv->format == CMYK) {
 157     unsigned char *row = rowPointer[0];
 158     for (unsigned int x = 0; x < priv->cinfo.image_width; x++) {
 159       for (int n = 0; n < 4; n++) {
 160         *row = 0xff - *row;
 161         row++;
 162       }
 163     }
 164   }
 165   // Write the row to the file
 166   jpeg_write_scanlines(&priv->cinfo, rowPointer, 1);
 167
 168   return true;
 169 }
 170
 171 bool JpegWriter::close()
 172 {
 173   jpeg_finish_compress(&priv->cinfo);
 174
 175   return true;
 176 }
 177
 178 bool JpegWriter::supportCMYK()
 179 {
 180   return priv->format == CMYK;
 181 }
 182
 183
 184 #endif