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.
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).
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).
18
* Based on code contributed by Mike Lijewski,
19
* with updates from Robert Hutchinson.
22
#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
26
/* rle.h is provided by the Utah Raster Toolkit. */
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.
35
#if BITS_IN_JSAMPLE != 8
36
Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
40
* We support the following types of RLE files:
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
48
* For now, we ignore any alpha channel in the image.
52
{ GRAYSCALE, MAPPEDGRAY, PSEUDOCOLOR, TRUECOLOR, DIRECTCOLOR } rle_kind;
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.
62
typedef struct _rle_source_struct * rle_source_ptr;
64
typedef struct _rle_source_struct {
65
struct cjpeg_source_struct pub; /* public fields */
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() */
77
* Read the file header; return image size and component count.
81
start_input_rle (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
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;
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))) {
97
ERREXIT(cinfo, JERR_RLE_NOT);
100
ERREXIT(cinfo, JERR_RLE_MEM);
103
ERREXIT(cinfo, JERR_RLE_EMPTY);
106
ERREXIT(cinfo, JERR_RLE_EOF);
109
ERREXIT(cinfo, JERR_RLE_BADERROR);
113
/* Figure out what we have, set private vars and return values accordingly */
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;
120
cinfo->image_width = width;
121
cinfo->image_height = height;
122
cinfo->data_precision = 8; /* we can only handle 8 bit data */
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);
143
ERREXIT(cinfo, JERR_RLE_UNSUPPORTED);
145
if (source->visual == GRAYSCALE || source->visual == MAPPEDGRAY) {
146
cinfo->in_color_space = JCS_GRAYSCALE;
147
cinfo->input_components = 1;
149
cinfo->in_color_space = JCS_RGB;
150
cinfo->input_components = 3;
154
* A place to hold each scanline while it's converted.
155
* (GRAYSCALE scanlines don't need converting)
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);
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);
169
#ifdef PROGRESS_REPORT
170
if (progress != NULL) {
171
/* count file input as separate pass */
172
progress->total_extra_passes++;
176
source->pub.buffer_height = 1;
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.
186
METHODDEF(JDIMENSION)
187
get_rle_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
189
rle_source_ptr source = (rle_source_ptr) sinfo;
192
source->pub.buffer = (*cinfo->mem->access_virt_sarray)
193
((j_common_ptr) cinfo, source->image, source->row, (JDIMENSION) 1, FALSE);
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.
204
METHODDEF(JDIMENSION)
205
get_pseudocolor_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
207
rle_source_ptr source = (rle_source_ptr) sinfo;
208
JSAMPROW src_row, dest_row;
213
colormap = source->header.cmap;
214
dest_row = source->pub.buffer[0];
216
src_row = * (*cinfo->mem->access_virt_sarray)
217
((j_common_ptr) cinfo, source->image, source->row, (JDIMENSION) 1, FALSE);
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);
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.
240
METHODDEF(JDIMENSION)
241
load_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
243
rle_source_ptr source = (rle_source_ptr) sinfo;
245
JSAMPROW scanline, red_ptr, green_ptr, blue_ptr;
249
#ifdef PROGRESS_REPORT
250
cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
253
colormap = source->header.cmap;
254
rle_row = source->rle_row;
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.
260
RLE_CLR_BIT(source->header, RLE_ALPHA); /* don't read the alpha channel */
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);
270
switch (source->visual) {
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);
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);
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);
302
#ifdef PROGRESS_REPORT
303
if (progress != NULL) {
304
progress->pub.pass_counter++;
305
(*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
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);
317
red_ptr = rle_row[0];
318
green_ptr = rle_row[1];
319
blue_ptr = rle_row[2];
321
for (col = cinfo->image_width; col > 0; col--) {
322
*scanline++ = *red_ptr++;
323
*scanline++ = *green_ptr++;
324
*scanline++ = *blue_ptr++;
327
#ifdef PROGRESS_REPORT
328
if (progress != NULL) {
329
progress->pub.pass_counter++;
330
(*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
336
#ifdef PROGRESS_REPORT
337
if (progress != NULL)
338
progress->completed_extra_passes++;
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;
346
source->pub.get_pixel_rows = get_rle_row;
348
source->row = cinfo->image_height;
350
/* And fetch the topmost (bottommost) row */
351
return (*source->pub.get_pixel_rows) (cinfo, sinfo);
356
* Finish up at the end of the file.
360
finish_input_rle (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
367
* The module selection routine for RLE format input.
370
GLOBAL(cjpeg_source_ptr)
371
jinit_read_rle (j_compress_ptr cinfo)
373
rle_source_ptr source;
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;
384
return (cjpeg_source_ptr) source;
387
#endif /* RLE_SUPPORTED */
added
removed
jpg/rdrle.c
