bitblt_g4.c

Fri, 21 Feb 2003 12:29:16 +0000

author
eric
date
Fri, 21 Feb 2003 12:29:16 +0000
changeset 70
16e2cf55dbd9
parent 67
7add7411c1c2
child 73
6e306105c128
permissions
-rw-r--r--

updated HDRS

     1 /*
     2  * t2p: Create a PDF file from the contents of one or more TIFF
     3  *      bilevel image files.  The images in the resulting PDF file
     4  *      will be compressed using ITU-T T.6 (G4) fax encoding.
     5  *
     6  * PDF routines
     7  * $Id: bitblt_g4.c,v 1.6 2003/02/21 02:49:11 eric Exp $
     8  * Copyright 2001, 2002, 2003 Eric Smith <eric@brouhaha.com>
     9  *
    10  * This program is free software; you can redistribute it and/or modify
    11  * it under the terms of the GNU General Public License version 2 as
    12  * published by the Free Software Foundation.  Note that permission is
    13  * not granted to redistribute this program under the terms of any
    14  * other version of the General Public License.
    15  *
    16  * This program is distributed in the hope that it will be useful,
    17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    19  * GNU General Public License for more details.
    20  *
    21  * You should have received a copy of the GNU General Public License
    22  * along with this program; if not, write to the Free Software
    23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA
    24  */
    27 #include <stdbool.h>
    28 #include <stdint.h>
    29 #include <stdio.h>
    30 #include <stdlib.h>
    31 #include <string.h>
    34 #include "bitblt.h"
    35 #include "pdf.h"
    36 #include "pdf_util.h"
    37 #include "pdf_prim.h"
    38 #include "pdf_private.h"
    41 #define SWAP(type,a,b) do { type temp; temp = a; a = b; b = temp; } while (0)
    44 struct pdf_g4_image
    45 {
    46   double width, height;
    47   double x, y;
    48   double r, g, b;  /* fill color, only for ImageMask */
    49   unsigned long Columns;
    50   unsigned long Rows;
    51   bool ImageMask;
    52   bool BlackIs1;
    53   Bitmap *bitmap;
    54   char XObject_name [4];
    55 };
    58 char pdf_new_XObject (pdf_page_handle pdf_page, struct pdf_obj *ind_ref)
    59 {
    60   char XObject_name [4] = "Im ";
    62   XObject_name [2] = ++pdf_page->last_XObject_name;
    64   if (! pdf_page->XObject_dict)
    65     {
    66       pdf_page->XObject_dict = pdf_new_obj (PT_DICTIONARY);
    67       pdf_set_dict_entry (pdf_page->resources, "XObject", pdf_page->XObject_dict);
    68     }
    70   pdf_set_dict_entry (pdf_page->XObject_dict, & XObject_name [0], ind_ref);
    72   return (pdf_page->last_XObject_name);
    73 }
    76 void pdf_write_g4_content_callback (pdf_file_handle pdf_file,
    77 				    struct pdf_obj *stream,
    78 				    void *app_data)
    79 {
    80   struct pdf_g4_image *image = app_data;
    82   /* transformation matrix is: width 0 0 height x y cm */
    83   pdf_stream_printf (pdf_file, stream, "q %g 0 0 %g %g %g cm ",
    84 		     image->width, image->height,
    85 		     image->x, image->y);
    86   if (image->ImageMask)
    87     pdf_stream_printf (pdf_file, stream, "%g %g %g rg ",
    88 		       image->r, image->g, image->b);
    90   pdf_stream_printf (pdf_file, stream, "/%s Do Q\r\n",
    91 		     image->XObject_name);
    92 }
    95 void pdf_write_g4_fax_image_callback (pdf_file_handle pdf_file,
    96 				      struct pdf_obj *stream,
    97 				      void *app_data)
    98 {
    99   struct pdf_g4_image *image = app_data;
   101   uint32_t row;
   103   /* reference (previous) row */
   104   uint32_t *ref_runs = pdf_calloc (image->Columns, sizeof (uint32_t));
   105   uint32_t ref_run_count;
   107   /* row being converted */
   108   uint32_t *row_runs = pdf_calloc (image->Columns, sizeof (uint32_t));
   109   uint32_t row_run_count;
   111   /* initialize reference row - all white */
   112   ref_runs [0] = image->Columns;
   113   ref_run_count = 0;
   115   for (row = image->bitmap->rect.min.y;
   116        row < image->bitmap->rect.max.y;
   117        row++)
   118     {
   119       row_run_count = get_row_run_lengths (image->bitmap,
   120 					   row,
   121 					   image->bitmap->rect.min.x,
   122 					   image->bitmap->rect.max.x - 1,
   123 					   image->Columns,  /* max_runs */
   124 					   row_runs);
   125       pdf_assert (row_run_count > 0);
   127       /* $$$ G4 encode the runs here */
   129       /* pdf_stream_write_data (pdf_file, stream, image->data, image->len); */
   131       SWAP (uint32_t *, row_runs, ref_runs);
   132       ref_run_count = row_run_count;
   133     }
   136   /* $$$ generate and write EOFB code */
   137   pdf_stream_write_bits (pdf_file, stream, 24, 0x001001);
   139   pdf_stream_flush_bits (pdf_file, stream);
   141   free (ref_runs);
   142   free (row_runs);
   143 }
   146 void pdf_write_g4_fax_image (pdf_page_handle pdf_page,
   147 			     double x,
   148 			     double y,
   149 			     double width,
   150 			     double height,
   151 			     Bitmap *bitmap,
   152 			     bool ImageMask,
   153 			     double r, /* RGB fill color, only for ImageMask */
   154 			     double g,
   155 			     double b,
   156 			     bool BlackIs1)          /* boolean, typ. false */
   157 {
   158   struct pdf_g4_image *image;
   160   struct pdf_obj *stream;
   161   struct pdf_obj *stream_dict;
   162   struct pdf_obj *decode_parms;
   164   struct pdf_obj *content_stream;
   166   image = pdf_calloc (1, sizeof (struct pdf_g4_image));
   168   image->width = width;
   169   image->height = height;
   170   image->x = x;
   171   image->y = y;
   172   image->r = r;
   173   image->g = g;
   174   image->b = b;
   176   image->bitmap = bitmap;
   177   image->Columns = bitmap->rect.max.x - bitmap->rect.min.x;
   178   image->Rows = bitmap->rect.max.y - bitmap->rect.min.y;
   179   image->ImageMask = ImageMask;
   180   image->BlackIs1 = BlackIs1;
   182   stream_dict = pdf_new_obj (PT_DICTIONARY);
   184   stream = pdf_new_ind_ref (pdf_page->pdf_file,
   185 			    pdf_new_stream (pdf_page->pdf_file,
   186 					    stream_dict,
   187 					    & pdf_write_g4_fax_image_callback,
   188 					    image));
   190   strcpy (& image->XObject_name [0], "Im ");
   191   image->XObject_name [2] = pdf_new_XObject (pdf_page, stream);
   193   pdf_set_dict_entry (stream_dict, "Type",    pdf_new_name ("XObject"));
   194   pdf_set_dict_entry (stream_dict, "Subtype", pdf_new_name ("Image"));
   195   pdf_set_dict_entry (stream_dict, "Name",    pdf_new_name (& image->XObject_name [0]));
   196   pdf_set_dict_entry (stream_dict, "Width",   pdf_new_integer (image->Columns));
   197   pdf_set_dict_entry (stream_dict, "Height",  pdf_new_integer (image->Rows));
   198   pdf_set_dict_entry (stream_dict, "BitsPerComponent", pdf_new_integer (1));
   199   if (ImageMask)
   200     pdf_set_dict_entry (stream_dict, "ImageMask", pdf_new_bool (ImageMask));
   201   else
   202     pdf_set_dict_entry (stream_dict, "ColorSpace", pdf_new_name ("DeviceGray"));
   204   decode_parms = pdf_new_obj (PT_DICTIONARY);
   206   pdf_set_dict_entry (decode_parms,
   207 		      "K",
   208 		      pdf_new_integer (-1));
   210   pdf_set_dict_entry (decode_parms,
   211 		      "Columns",
   212 		      pdf_new_integer (image->Columns));
   214   pdf_set_dict_entry (decode_parms,
   215 		      "Rows",
   216 		      pdf_new_integer (image->Rows));
   218   if (BlackIs1)
   219     pdf_set_dict_entry (decode_parms,
   220 			"BlackIs1",
   221 			pdf_new_bool (BlackIs1));
   223   pdf_stream_add_filter (stream, "CCITTFaxDecode", decode_parms);
   225   /* the following will write the stream, using our callback function to
   226      get the actual data */
   227   pdf_write_ind_obj (pdf_page->pdf_file, stream);
   229   content_stream = pdf_new_ind_ref (pdf_page->pdf_file,
   230 				    pdf_new_stream (pdf_page->pdf_file,
   231 						    pdf_new_obj (PT_DICTIONARY),
   232 						    & pdf_write_g4_content_callback,
   233 						    image));
   235   pdf_set_dict_entry (pdf_page->page_dict, "Contents", content_stream);
   237   pdf_write_ind_obj (pdf_page->pdf_file, content_stream);
   238 }