wrlib/tiff.c

   1 /* tiff.c - load TIFF image from file
   2  *
   3  * Raster graphics library
   4  *
   5  * Copyright (c) 1997-2003 Alfredo K. Kojima
   6  *
   7  *  This library is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU Library General Public
   9  *  License as published by the Free Software Foundation; either
  10  *  version 2 of the License, or (at your option) any later version.
  11  *
  12  *  This library is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  *  Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU Library General Public
  18  *  License along with this library; if not, write to the Free
  19  *  Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  20  *  MA 02110-1301, USA.
  21  */
  22
  23 #include <config.h>
  24
  25 #ifdef USE_TIFF
  26
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30
  31 #include <tiff.h>
  32 #include <tiffio.h>
  33
  34 #include "wraster.h"
  35 #include "imgformat.h"
  36
  37 RImage *RLoadTIFF(const char *file, int index)
  38 {
  39         RImage *image = NULL;
  40         TIFF *tif;
  41         int i;
  42         unsigned char *r, *g, *b, *a;
  43         uint16 alpha, amode;
  44         uint32 width, height;
  45         uint32 *data, *ptr;
  46         uint16 extrasamples;
  47         uint16 *sampleinfo;
  48         int ch;
  49
  50         tif = TIFFOpen(file, "r");
  51         if (!tif)
  52                 return NULL;
  53
  54         /* seek index */
  55         i = index;
  56         while (i > 0) {
  57                 if (!TIFFReadDirectory(tif)) {
  58                         RErrorCode = RERR_BADINDEX;
  59                         TIFFClose(tif);
  60                         return NULL;
  61                 }
  62                 i--;
  63         }
  64
  65         /* get info */
  66         TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &width);
  67         TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &height);
  68
  69         TIFFGetFieldDefaulted(tif, TIFFTAG_EXTRASAMPLES, &extrasamples, &sampleinfo);
  70
  71         alpha = (extrasamples == 1 &&
  72                  ((sampleinfo[0] == EXTRASAMPLE_ASSOCALPHA) || (sampleinfo[0] == EXTRASAMPLE_UNASSALPHA)));
  73         amode = (extrasamples == 1 && sampleinfo[0] == EXTRASAMPLE_ASSOCALPHA);
  74
  75         if (width < 1 || height < 1) {
  76                 RErrorCode = RERR_BADIMAGEFILE;
  77                 TIFFClose(tif);
  78                 return NULL;
  79         }
  80
  81         /* read data */
  82         ptr = data = (uint32 *) _TIFFmalloc(width * height * sizeof(uint32));
  83
  84         if (!data) {
  85                 RErrorCode = RERR_NOMEMORY;
  86         } else {
  87                 if (!TIFFReadRGBAImage(tif, width, height, data, 0)) {
  88                         RErrorCode = RERR_BADIMAGEFILE;
  89                 } else {
  90
  91                         /* convert data */
  92                         image = RCreateImage(width, height, alpha);
  93
  94                         if (alpha)
  95                                 ch = 4;
  96                         else
  97                                 ch = 3;
  98
  99                         if (image) {
 100                                 int x, y;
 101
 102                                 r = image->data;
 103                                 g = image->data + 1;
 104                                 b = image->data + 2;
 105                                 a = image->data + 3;
 106
 107                                 /* data seems to be stored upside down */
 108                                 data += width * (height - 1);
 109                                 for (y = 0; y < height; y++) {
 110                                         for (x = 0; x < width; x++) {
 111
 112                                                 *(r) = (*data) & 0xff;
 113                                                 *(g) = (*data >> 8) & 0xff;
 114                                                 *(b) = (*data >> 16) & 0xff;
 115
 116                                                 if (alpha) {
 117                                                         *(a) = (*data >> 24) & 0xff;
 118
 119                                                         if (amode && (*a > 0)) {
 120                                                                 *r = (*r * 255) / *(a);
 121                                                                 *g = (*g * 255) / *(a);
 122                                                                 *b = (*b * 255) / *(a);
 123                                                         }
 124
 125                                                         a += 4;
 126                                                 }
 127
 128                                                 r += ch;
 129                                                 g += ch;
 130                                                 b += ch;
 131                                                 data++;
 132                                         }
 133                                         data -= 2 * width;
 134                                 }
 135                         }
 136                 }
 137                 _TIFFfree(ptr);
 138         }
 139
 140         TIFFClose(tif);
 141
 142         return image;
 143 }
 144
 145 #endif                          /* USE_TIFF */