1/*
2 * rdrle.c
3 *
4 * Copyright (C) 1991-1996, Thomas G. Lane.
5 * This file is part of the Independent JPEG Group's software.
6 * For conditions of distribution and use, see the accompanying README file.
7 *
8 * This file contains routines to read input images in Utah RLE format.
9 * The Utah Raster Toolkit library is required (version 3.1 or later).
10 *
11 * These routines may need modification for non-Unix environments or
12 * specialized applications.  As they stand, they assume input from
13 * an ordinary stdio stream.  They further assume that reading begins
14 * at the start of the file; start_input may need work if the
15 * user interface has already read some data (e.g., to determine that
16 * the file is indeed RLE format).
17 *
18 * Based on code contributed by Mike Lijewski,
19 * with updates from Robert Hutchinson.
20 */
21
22#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */
23
24#ifdef RLE_SUPPORTED
25
26/* rle.h is provided by the Utah Raster Toolkit. */
27
28#include <rle.h>
29
30/*
31 * We assume that JSAMPLE has the same representation as rle_pixel,
32 * to wit, "unsigned char".  Hence we can't cope with 12- or 16-bit samples.
33 */
34
35#if BITS_IN_JSAMPLE != 8
36  Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
37#endif
38
39/*
40 * We support the following types of RLE files:
41 *
42 *   GRAYSCALE   - 8 bits, no colormap
43 *   MAPPEDGRAY  - 8 bits, 1 channel colomap
44 *   PSEUDOCOLOR - 8 bits, 3 channel colormap
45 *   TRUECOLOR   - 24 bits, 3 channel colormap
46 *   DIRECTCOLOR - 24 bits, no colormap
47 *
48 * For now, we ignore any alpha channel in the image.
49 */
50
51typedef enum
52  { GRAYSCALE, MAPPEDGRAY, PSEUDOCOLOR, TRUECOLOR, DIRECTCOLOR } rle_kind;
53
54
55/*
56 * Since RLE stores scanlines bottom-to-top, we have to invert the image
57 * to conform to JPEG's top-to-bottom order.  To do this, we read the
58 * incoming image into a virtual array on the first get_pixel_rows call,
59 * then fetch the required row from the virtual array on subsequent calls.
60 */
61
62typedef struct _rle_source_struct * rle_source_ptr;
63
64typedef struct _rle_source_struct {
65  struct cjpeg_source_struct pub; /* public fields */
66
67  rle_kind visual;              /* actual type of input file */
68  jvirt_sarray_ptr image;       /* virtual array to hold the image */
69  JDIMENSION row;		/* current row # in the virtual array */
70  rle_hdr header;               /* Input file information */
71  rle_pixel** rle_row;          /* holds a row returned by rle_getrow() */
72
73} rle_source_struct;
74
75
76/*
77 * Read the file header; return image size and component count.
78 */
79
80METHODDEF(void)
81start_input_rle (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
82{
83  rle_source_ptr source = (rle_source_ptr) sinfo;
84  JDIMENSION width, height;
85#ifdef PROGRESS_REPORT
86  cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
87#endif
88
89  /* Use RLE library routine to get the header info */
90  source->header = *rle_hdr_init(NULL);
91  source->header.rle_file = source->pub.input_file;
92  switch (rle_get_setup(&(source->header))) {
93  case RLE_SUCCESS:
94    /* A-OK */
95    break;
96  case RLE_NOT_RLE:
97    ERREXIT(cinfo, JERR_RLE_NOT);
98    break;
99  case RLE_NO_SPACE:
100    ERREXIT(cinfo, JERR_RLE_MEM);
101    break;
102  case RLE_EMPTY:
103    ERREXIT(cinfo, JERR_RLE_EMPTY);
104    break;
105  case RLE_EOF:
106    ERREXIT(cinfo, JERR_RLE_EOF);
107    break;
108  default:
109    ERREXIT(cinfo, JERR_RLE_BADERROR);
110    break;
111  }
112
113  /* Figure out what we have, set private vars and return values accordingly */
114
115  width  = source->header.xmax - source->header.xmin + 1;
116  height = source->header.ymax - source->header.ymin + 1;
117  source->header.xmin = 0;		/* realign horizontally */
118  source->header.xmax = width-1;
119
120  cinfo->image_width      = width;
121  cinfo->image_height     = height;
122  cinfo->data_precision   = 8;  /* we can only handle 8 bit data */
123
124  if (source->header.ncolors == 1 && source->header.ncmap == 0) {
125    source->visual     = GRAYSCALE;
126    TRACEMS2(cinfo, 1, JTRC_RLE_GRAY, width, height);
127  } else if (source->header.ncolors == 1 && source->header.ncmap == 1) {
128    source->visual     = MAPPEDGRAY;
129    TRACEMS3(cinfo, 1, JTRC_RLE_MAPGRAY, width, height,
130             1 << source->header.cmaplen);
131  } else if (source->header.ncolors == 1 && source->header.ncmap == 3) {
132    source->visual     = PSEUDOCOLOR;
133    TRACEMS3(cinfo, 1, JTRC_RLE_MAPPED, width, height,
134	     1 << source->header.cmaplen);
135  } else if (source->header.ncolors == 3 && source->header.ncmap == 3) {
136    source->visual     = TRUECOLOR;
137    TRACEMS3(cinfo, 1, JTRC_RLE_FULLMAP, width, height,
138	     1 << source->header.cmaplen);
139  } else if (source->header.ncolors == 3 && source->header.ncmap == 0) {
140    source->visual     = DIRECTCOLOR;
141    TRACEMS2(cinfo, 1, JTRC_RLE, width, height);
142  } else
143    ERREXIT(cinfo, JERR_RLE_UNSUPPORTED);
144
145  if (source->visual == GRAYSCALE || source->visual == MAPPEDGRAY) {
146    cinfo->in_color_space   = JCS_GRAYSCALE;
147    cinfo->input_components = 1;
148  } else {
149    cinfo->in_color_space   = JCS_RGB;
150    cinfo->input_components = 3;
151  }
152
153  /*
154   * A place to hold each scanline while it's converted.
155   * (GRAYSCALE scanlines don't need converting)
156   */
157  if (source->visual != GRAYSCALE) {
158    source->rle_row = (rle_pixel**) (*cinfo->mem->alloc_sarray)
159      ((j_common_ptr) cinfo, JPOOL_IMAGE,
160       (JDIMENSION) width, (JDIMENSION) cinfo->input_components);
161  }
162
163  /* request a virtual array to hold the image */
164  source->image = (*cinfo->mem->request_virt_sarray)
165    ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
166     (JDIMENSION) (width * source->header.ncolors),
167     (JDIMENSION) height, (JDIMENSION) 1);
168
169#ifdef PROGRESS_REPORT
170  if (progress != NULL) {
171    /* count file input as separate pass */
172    progress->total_extra_passes++;
173  }
174#endif
175
176  source->pub.buffer_height = 1;
177}
178
179
180/*
181 * Read one row of pixels.
182 * Called only after load_image has read the image into the virtual array.
183 * Used for GRAYSCALE, MAPPEDGRAY, TRUECOLOR, and DIRECTCOLOR images.
184 */
185
186METHODDEF(JDIMENSION)
187get_rle_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
188{
189  rle_source_ptr source = (rle_source_ptr) sinfo;
190
191  source->row--;
192  source->pub.buffer = (*cinfo->mem->access_virt_sarray)
193    ((j_common_ptr) cinfo, source->image, source->row, (JDIMENSION) 1, FALSE);
194
195  return 1;
196}
197
198/*
199 * Read one row of pixels.
200 * Called only after load_image has read the image into the virtual array.
201 * Used for PSEUDOCOLOR images.
202 */
203
204METHODDEF(JDIMENSION)
205get_pseudocolor_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
206{
207  rle_source_ptr source = (rle_source_ptr) sinfo;
208  JSAMPROW src_row, dest_row;
209  JDIMENSION col;
210  rle_map *colormap;
211  int val;
212
213  colormap = source->header.cmap;
214  dest_row = source->pub.buffer[0];
215  source->row--;
216  src_row = * (*cinfo->mem->access_virt_sarray)
217    ((j_common_ptr) cinfo, source->image, source->row, (JDIMENSION) 1, FALSE);
218
219  for (col = cinfo->image_width; col > 0; col--) {
220    val = GETJSAMPLE(*src_row++);
221    *dest_row++ = (JSAMPLE) (colormap[val      ] >> 8);
222    *dest_row++ = (JSAMPLE) (colormap[val + 256] >> 8);
223    *dest_row++ = (JSAMPLE) (colormap[val + 512] >> 8);
224  }
225
226  return 1;
227}
228
229
230/*
231 * Load the image into a virtual array.  We have to do this because RLE
232 * files start at the lower left while the JPEG standard has them starting
233 * in the upper left.  This is called the first time we want to get a row
234 * of input.  What we do is load the RLE data into the array and then call
235 * the appropriate routine to read one row from the array.  Before returning,
236 * we set source->pub.get_pixel_rows so that subsequent calls go straight to
237 * the appropriate row-reading routine.
238 */
239
240METHODDEF(JDIMENSION)
241load_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
242{
243  rle_source_ptr source = (rle_source_ptr) sinfo;
244  JDIMENSION row, col;
245  JSAMPROW  scanline, red_ptr, green_ptr, blue_ptr;
246  rle_pixel **rle_row;
247  rle_map *colormap;
248  char channel;
249#ifdef PROGRESS_REPORT
250  cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
251#endif
252
253  colormap = source->header.cmap;
254  rle_row = source->rle_row;
255
256  /* Read the RLE data into our virtual array.
257   * We assume here that (a) rle_pixel is represented the same as JSAMPLE,
258   * and (b) we are not on a machine where FAR pointers differ from regular.
259   */
260  RLE_CLR_BIT(source->header, RLE_ALPHA); /* don't read the alpha channel */
261
262#ifdef PROGRESS_REPORT
263  if (progress != NULL) {
264    progress->pub.pass_limit = cinfo->image_height;
265    progress->pub.pass_counter = 0;
266    (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
267  }
268#endif
269
270  switch (source->visual) {
271
272  case GRAYSCALE:
273  case PSEUDOCOLOR:
274    for (row = 0; row < cinfo->image_height; row++) {
275      rle_row = (rle_pixel **) (*cinfo->mem->access_virt_sarray)
276         ((j_common_ptr) cinfo, source->image, row, (JDIMENSION) 1, TRUE);
277      rle_getrow(&source->header, rle_row);
278#ifdef PROGRESS_REPORT
279      if (progress != NULL) {
280        progress->pub.pass_counter++;
281        (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
282      }
283#endif
284    }
285    break;
286
287  case MAPPEDGRAY:
288  case TRUECOLOR:
289    for (row = 0; row < cinfo->image_height; row++) {
290      scanline = * (*cinfo->mem->access_virt_sarray)
291        ((j_common_ptr) cinfo, source->image, row, (JDIMENSION) 1, TRUE);
292      rle_row = source->rle_row;
293      rle_getrow(&source->header, rle_row);
294
295      for (col = 0; col < cinfo->image_width; col++) {
296        for (channel = 0; channel < source->header.ncolors; channel++) {
297          *scanline++ = (JSAMPLE)
298            (colormap[GETJSAMPLE(rle_row[channel][col]) + 256 * channel] >> 8);
299        }
300      }
301
302#ifdef PROGRESS_REPORT
303      if (progress != NULL) {
304        progress->pub.pass_counter++;
305        (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
306      }
307#endif
308    }
309    break;
310
311  case DIRECTCOLOR:
312    for (row = 0; row < cinfo->image_height; row++) {
313      scanline = * (*cinfo->mem->access_virt_sarray)
314        ((j_common_ptr) cinfo, source->image, row, (JDIMENSION) 1, TRUE);
315      rle_getrow(&source->header, rle_row);
316
317      red_ptr   = rle_row[0];
318      green_ptr = rle_row[1];
319      blue_ptr  = rle_row[2];
320
321      for (col = cinfo->image_width; col > 0; col--) {
322        *scanline++ = *red_ptr++;
323        *scanline++ = *green_ptr++;
324        *scanline++ = *blue_ptr++;
325      }
326
327#ifdef PROGRESS_REPORT
328      if (progress != NULL) {
329        progress->pub.pass_counter++;
330        (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
331      }
332#endif
333    }
334  }
335
336#ifdef PROGRESS_REPORT
337  if (progress != NULL)
338    progress->completed_extra_passes++;
339#endif
340
341  /* Set up to call proper row-extraction routine in future */
342  if (source->visual == PSEUDOCOLOR) {
343    source->pub.buffer = source->rle_row;
344    source->pub.get_pixel_rows = get_pseudocolor_row;
345  } else {
346    source->pub.get_pixel_rows = get_rle_row;
347  }
348  source->row = cinfo->image_height;
349
350  /* And fetch the topmost (bottommost) row */
351  return (*source->pub.get_pixel_rows) (cinfo, sinfo);
352}
353
354
355/*
356 * Finish up at the end of the file.
357 */
358
359METHODDEF(void)
360finish_input_rle (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
361{
362  /* no work */
363}
364
365
366/*
367 * The module selection routine for RLE format input.
368 */
369
370GLOBAL(cjpeg_source_ptr)
371jinit_read_rle (j_compress_ptr cinfo)
372{
373  rle_source_ptr source;
374
375  /* Create module interface object */
376  source = (rle_source_ptr)
377      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
378                                  SIZEOF(rle_source_struct));
379  /* Fill in method ptrs */
380  source->pub.start_input = start_input_rle;
381  source->pub.finish_input = finish_input_rle;
382  source->pub.get_pixel_rows = load_image;
383
384  return (cjpeg_source_ptr) source;
385}
386
387#endif /* RLE_SUPPORTED */
388