summaryrefslogtreecommitdiff
path: root/jpeg/wrrle.c
blob: a4e73372de66f86d0e8b4046f716b25cb1d5ad74 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
/*
 * wrrle.c
 *
 * Copyright (C) 1991-1996, Thomas G. Lane.
 * This file is part of the Independent JPEG Group's software.
 * For conditions of distribution and use, see the accompanying README file.
 *
 * This file contains routines to write output images in RLE format.
 * The Utah Raster Toolkit library is required (version 3.1 or later).
 *
 * These routines may need modification for non-Unix environments or
 * specialized applications.  As they stand, they assume output to
 * an ordinary stdio stream.
 *
 * Based on code contributed by Mike Lijewski,
 * with updates from Robert Hutchinson.
 */

#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */

#ifdef RLE_SUPPORTED

/* rle.h is provided by the Utah Raster Toolkit. */

#include <rle.h>

/*
 * We assume that JSAMPLE has the same representation as rle_pixel,
 * to wit, "unsigned char".  Hence we can't cope with 12- or 16-bit samples.
 */

#if BITS_IN_JSAMPLE != 8
  Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
#endif


/*
 * Since RLE stores scanlines bottom-to-top, we have to invert the image
 * from JPEG's top-to-bottom order.  To do this, we save the outgoing data
 * in a virtual array during put_pixel_row calls, then actually emit the
 * RLE file during finish_output.
 */


/*
 * For now, if we emit an RLE color map then it is always 256 entries long,
 * though not all of the entries need be used.
 */

#define CMAPBITS	8
#define CMAPLENGTH	(1<<(CMAPBITS))

typedef struct {
  struct djpeg_dest_struct pub; /* public fields */

  jvirt_sarray_ptr image;	/* virtual array to store the output image */
  rle_map *colormap;	 	/* RLE-style color map, or NULL if none */
  rle_pixel **rle_row;		/* To pass rows to rle_putrow() */

} rle_dest_struct;

typedef rle_dest_struct * rle_dest_ptr;

/* Forward declarations */
METHODDEF(void) rle_put_pixel_rows
    JPP((j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
	 JDIMENSION rows_supplied));


/*
 * Write the file header.
 *
 * In this module it's easier to wait till finish_output to write anything.
 */

METHODDEF(void)
start_output_rle (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
{
  rle_dest_ptr dest = (rle_dest_ptr) dinfo;
  size_t cmapsize;
  int i, ci;
#ifdef PROGRESS_REPORT
  cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
#endif

  /*
   * Make sure the image can be stored in RLE format.
   *
   * - RLE stores image dimensions as *signed* 16 bit integers.  JPEG
   *   uses unsigned, so we have to check the width.
   *
   * - Colorspace is expected to be grayscale or RGB.
   *
   * - The number of channels (components) is expected to be 1 (grayscale/
   *   pseudocolor) or 3 (truecolor/directcolor).
   *   (could be 2 or 4 if using an alpha channel, but we aren't)
   */

  if (cinfo->output_width > 32767 || cinfo->output_height > 32767)
    ERREXIT2(cinfo, JERR_RLE_DIMENSIONS, cinfo->output_width, 
	     cinfo->output_height);

  if (cinfo->out_color_space != JCS_GRAYSCALE &&
      cinfo->out_color_space != JCS_RGB)
    ERREXIT(cinfo, JERR_RLE_COLORSPACE);

  if (cinfo->output_components != 1 && cinfo->output_components != 3)
    ERREXIT1(cinfo, JERR_RLE_TOOMANYCHANNELS, cinfo->num_components);

  /* Convert colormap, if any, to RLE format. */

  dest->colormap = NULL;

  if (cinfo->quantize_colors) {
    /* Allocate storage for RLE-style cmap, zero any extra entries */
    cmapsize = cinfo->out_color_components * CMAPLENGTH * SIZEOF(rle_map);
    dest->colormap = (rle_map *) (*cinfo->mem->alloc_small)
      ((j_common_ptr) cinfo, JPOOL_IMAGE, cmapsize);
    MEMZERO(dest->colormap, cmapsize);

    /* Save away data in RLE format --- note 8-bit left shift! */
    /* Shifting would need adjustment for JSAMPLEs wider than 8 bits. */
    for (ci = 0; ci < cinfo->out_color_components; ci++) {
      for (i = 0; i < cinfo->actual_number_of_colors; i++) {
        dest->colormap[ci * CMAPLENGTH + i] =
          GETJSAMPLE(cinfo->colormap[ci][i]) << 8;
      }
    }
  }

  /* Set the output buffer to the first row */
  dest->pub.buffer = (*cinfo->mem->access_virt_sarray)
    ((j_common_ptr) cinfo, dest->image, (JDIMENSION) 0, (JDIMENSION) 1, TRUE);
  dest->pub.buffer_height = 1;

  dest->pub.put_pixel_rows = rle_put_pixel_rows;

#ifdef PROGRESS_REPORT
  if (progress != NULL) {
    progress->total_extra_passes++;  /* count file writing as separate pass */
  }
#endif
}


/*
 * Write some pixel data.
 *
 * This routine just saves the data away in a virtual array.
 */

METHODDEF(void)
rle_put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
		    JDIMENSION rows_supplied)
{
  rle_dest_ptr dest = (rle_dest_ptr) dinfo;

  if (cinfo->output_scanline < cinfo->output_height) {
    dest->pub.buffer = (*cinfo->mem->access_virt_sarray)
      ((j_common_ptr) cinfo, dest->image,
       cinfo->output_scanline, (JDIMENSION) 1, TRUE);
  }
}

/*
 * Finish up at the end of the file.
 *
 * Here is where we really output the RLE file.
 */

METHODDEF(void)
finish_output_rle (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
{
  rle_dest_ptr dest = (rle_dest_ptr) dinfo;
  rle_hdr header;		/* Output file information */
  rle_pixel **rle_row, *red, *green, *blue;
  JSAMPROW output_row;
  char cmapcomment[80];
  int row, col;
  int ci;
#ifdef PROGRESS_REPORT
  cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
#endif

  /* Initialize the header info */
  header = *rle_hdr_init(NULL);
  header.rle_file = dest->pub.output_file;
  header.xmin     = 0;
  header.xmax     = cinfo->output_width  - 1;
  header.ymin     = 0;
  header.ymax     = cinfo->output_height - 1;
  header.alpha    = 0;
  header.ncolors  = cinfo->output_components;
  for (ci = 0; ci < cinfo->output_components; ci++) {
    RLE_SET_BIT(header, ci);
  }
  if (cinfo->quantize_colors) {
    header.ncmap   = cinfo->out_color_components;
    header.cmaplen = CMAPBITS;
    header.cmap    = dest->colormap;
    /* Add a comment to the output image with the true colormap length. */
    sprintf(cmapcomment, "color_map_length=%d", cinfo->actual_number_of_colors);
    rle_putcom(cmapcomment, &header);
  }

  /* Emit the RLE header and color map (if any) */
  rle_put_setup(&header);

  /* Now output the RLE data from our virtual array.
   * We assume here that (a) rle_pixel is represented the same as JSAMPLE,
   * and (b) we are not on a machine where FAR pointers differ from regular.
   */

#ifdef PROGRESS_REPORT
  if (progress != NULL) {
    progress->pub.pass_limit = cinfo->output_height;
    progress->pub.pass_counter = 0;
    (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
  }
#endif

  if (cinfo->output_components == 1) {
    for (row = cinfo->output_height-1; row >= 0; row--) {
      rle_row = (rle_pixel **) (*cinfo->mem->access_virt_sarray)
        ((j_common_ptr) cinfo, dest->image,
	 (JDIMENSION) row, (JDIMENSION) 1, FALSE);
      rle_putrow(rle_row, (int) cinfo->output_width, &header);
#ifdef PROGRESS_REPORT
      if (progress != NULL) {
        progress->pub.pass_counter++;
        (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
      }
#endif
    }
  } else {
    for (row = cinfo->output_height-1; row >= 0; row--) {
      rle_row = (rle_pixel **) dest->rle_row;
      output_row = * (*cinfo->mem->access_virt_sarray)
        ((j_common_ptr) cinfo, dest->image,
	 (JDIMENSION) row, (JDIMENSION) 1, FALSE);
      red = rle_row[0];
      green = rle_row[1];
      blue = rle_row[2];
      for (col = cinfo->output_width; col > 0; col--) {
        *red++ = GETJSAMPLE(*output_row++);
        *green++ = GETJSAMPLE(*output_row++);
        *blue++ = GETJSAMPLE(*output_row++);
      }
      rle_putrow(rle_row, (int) cinfo->output_width, &header);
#ifdef PROGRESS_REPORT
      if (progress != NULL) {
        progress->pub.pass_counter++;
        (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
      }
#endif
    }
  }

#ifdef PROGRESS_REPORT
  if (progress != NULL)
    progress->completed_extra_passes++;
#endif

  /* Emit file trailer */
  rle_puteof(&header);
  fflush(dest->pub.output_file);
  if (ferror(dest->pub.output_file))
    ERREXIT(cinfo, JERR_FILE_WRITE);
}


/*
 * The module selection routine for RLE format output.
 */

GLOBAL(djpeg_dest_ptr)
jinit_write_rle (j_decompress_ptr cinfo)
{
  rle_dest_ptr dest;

  /* Create module interface object, fill in method pointers */
  dest = (rle_dest_ptr)
      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                  SIZEOF(rle_dest_struct));
  dest->pub.start_output = start_output_rle;
  dest->pub.finish_output = finish_output_rle;

  /* Calculate output image dimensions so we can allocate space */
  jpeg_calc_output_dimensions(cinfo);

  /* Allocate a work array for output to the RLE library. */
  dest->rle_row = (*cinfo->mem->alloc_sarray)
    ((j_common_ptr) cinfo, JPOOL_IMAGE,
     cinfo->output_width, (JDIMENSION) cinfo->output_components);

  /* Allocate a virtual array to hold the image. */
  dest->image = (*cinfo->mem->request_virt_sarray)
    ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
     (JDIMENSION) (cinfo->output_width * cinfo->output_components),
     cinfo->output_height, (JDIMENSION) 1);

  return (djpeg_dest_ptr) dest;
}

#endif /* RLE_SUPPORTED */