4c2cd26730a8af052bd674bb1aba7af0295a8d19
[reactos.git] / dll / 3rdparty / libjpeg / rdtarga.c
1 /*
2 * rdtarga.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 Targa format.
9 *
10 * These routines may need modification for non-Unix environments or
11 * specialized applications. As they stand, they assume input from
12 * an ordinary stdio stream. They further assume that reading begins
13 * at the start of the file; start_input may need work if the
14 * user interface has already read some data (e.g., to determine that
15 * the file is indeed Targa format).
16 *
17 * Based on code contributed by Lee Daniel Crocker.
18 */
19
20 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
21
22 #ifdef TARGA_SUPPORTED
23
24
25 /* Macros to deal with unsigned chars as efficiently as compiler allows */
26
27 #ifdef HAVE_UNSIGNED_CHAR
28 typedef unsigned char U_CHAR;
29 #define UCH(x) ((int) (x))
30 #else /* !HAVE_UNSIGNED_CHAR */
31 #ifdef CHAR_IS_UNSIGNED
32 typedef char U_CHAR;
33 #define UCH(x) ((int) (x))
34 #else
35 typedef char U_CHAR;
36 #define UCH(x) ((int) (x) & 0xFF)
37 #endif
38 #endif /* HAVE_UNSIGNED_CHAR */
39
40
41 #define ReadOK(file,buffer,len) (JFREAD(file,buffer,len) == ((size_t) (len)))
42
43
44 /* Private version of data source object */
45
46 typedef struct _tga_source_struct * tga_source_ptr;
47
48 typedef struct _tga_source_struct {
49 struct cjpeg_source_struct pub; /* public fields */
50
51 j_compress_ptr cinfo; /* back link saves passing separate parm */
52
53 JSAMPARRAY colormap; /* Targa colormap (converted to my format) */
54
55 jvirt_sarray_ptr whole_image; /* Needed if funny input row order */
56 JDIMENSION current_row; /* Current logical row number to read */
57
58 /* Pointer to routine to extract next Targa pixel from input file */
59 JMETHOD(void, read_pixel, (tga_source_ptr sinfo));
60
61 /* Result of read_pixel is delivered here: */
62 U_CHAR tga_pixel[4];
63
64 int pixel_size; /* Bytes per Targa pixel (1 to 4) */
65
66 /* State info for reading RLE-coded pixels; both counts must be init to 0 */
67 int block_count; /* # of pixels remaining in RLE block */
68 int dup_pixel_count; /* # of times to duplicate previous pixel */
69
70 /* This saves the correct pixel-row-expansion method for preload_image */
71 JMETHOD(JDIMENSION, get_pixel_rows, (j_compress_ptr cinfo,
72 cjpeg_source_ptr sinfo));
73 } tga_source_struct;
74
75
76 /* For expanding 5-bit pixel values to 8-bit with best rounding */
77
78 static const UINT8 c5to8bits[32] = {
79 0, 8, 16, 25, 33, 41, 49, 58,
80 66, 74, 82, 90, 99, 107, 115, 123,
81 132, 140, 148, 156, 165, 173, 181, 189,
82 197, 206, 214, 222, 230, 239, 247, 255
83 };
84
85
86
87 LOCAL(int)
88 read_byte (tga_source_ptr sinfo)
89 /* Read next byte from Targa file */
90 {
91 register FILE *infile = sinfo->pub.input_file;
92 register int c;
93
94 if ((c = getc(infile)) == EOF)
95 ERREXIT(sinfo->cinfo, JERR_INPUT_EOF);
96 return c;
97 }
98
99
100 LOCAL(void)
101 read_colormap (tga_source_ptr sinfo, int cmaplen, int mapentrysize)
102 /* Read the colormap from a Targa file */
103 {
104 int i;
105
106 /* Presently only handles 24-bit BGR format */
107 if (mapentrysize != 24)
108 ERREXIT(sinfo->cinfo, JERR_TGA_BADCMAP);
109
110 for (i = 0; i < cmaplen; i++) {
111 sinfo->colormap[2][i] = (JSAMPLE) read_byte(sinfo);
112 sinfo->colormap[1][i] = (JSAMPLE) read_byte(sinfo);
113 sinfo->colormap[0][i] = (JSAMPLE) read_byte(sinfo);
114 }
115 }
116
117
118 /*
119 * read_pixel methods: get a single pixel from Targa file into tga_pixel[]
120 */
121
122 METHODDEF(void)
123 read_non_rle_pixel (tga_source_ptr sinfo)
124 /* Read one Targa pixel from the input file; no RLE expansion */
125 {
126 register FILE *infile = sinfo->pub.input_file;
127 register int i;
128
129 for (i = 0; i < sinfo->pixel_size; i++) {
130 sinfo->tga_pixel[i] = (U_CHAR) getc(infile);
131 }
132 }
133
134
135 METHODDEF(void)
136 read_rle_pixel (tga_source_ptr sinfo)
137 /* Read one Targa pixel from the input file, expanding RLE data as needed */
138 {
139 register FILE *infile = sinfo->pub.input_file;
140 register int i;
141
142 /* Duplicate previously read pixel? */
143 if (sinfo->dup_pixel_count > 0) {
144 sinfo->dup_pixel_count--;
145 return;
146 }
147
148 /* Time to read RLE block header? */
149 if (--sinfo->block_count < 0) { /* decrement pixels remaining in block */
150 i = read_byte(sinfo);
151 if (i & 0x80) { /* Start of duplicate-pixel block? */
152 sinfo->dup_pixel_count = i & 0x7F; /* number of dups after this one */
153 sinfo->block_count = 0; /* then read new block header */
154 } else {
155 sinfo->block_count = i & 0x7F; /* number of pixels after this one */
156 }
157 }
158
159 /* Read next pixel */
160 for (i = 0; i < sinfo->pixel_size; i++) {
161 sinfo->tga_pixel[i] = (U_CHAR) getc(infile);
162 }
163 }
164
165
166 /*
167 * Read one row of pixels.
168 *
169 * We provide several different versions depending on input file format.
170 */
171
172
173 METHODDEF(JDIMENSION)
174 get_8bit_gray_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
175 /* This version is for reading 8-bit grayscale pixels */
176 {
177 tga_source_ptr source = (tga_source_ptr) sinfo;
178 register JSAMPROW ptr;
179 register JDIMENSION col;
180
181 ptr = source->pub.buffer[0];
182 for (col = cinfo->image_width; col > 0; col--) {
183 (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
184 *ptr++ = (JSAMPLE) UCH(source->tga_pixel[0]);
185 }
186 return 1;
187 }
188
189 METHODDEF(JDIMENSION)
190 get_8bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
191 /* This version is for reading 8-bit colormap indexes */
192 {
193 tga_source_ptr source = (tga_source_ptr) sinfo;
194 register int t;
195 register JSAMPROW ptr;
196 register JDIMENSION col;
197 register JSAMPARRAY colormap = source->colormap;
198
199 ptr = source->pub.buffer[0];
200 for (col = cinfo->image_width; col > 0; col--) {
201 (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
202 t = UCH(source->tga_pixel[0]);
203 *ptr++ = colormap[0][t];
204 *ptr++ = colormap[1][t];
205 *ptr++ = colormap[2][t];
206 }
207 return 1;
208 }
209
210 METHODDEF(JDIMENSION)
211 get_16bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
212 /* This version is for reading 16-bit pixels */
213 {
214 tga_source_ptr source = (tga_source_ptr) sinfo;
215 register int t;
216 register JSAMPROW ptr;
217 register JDIMENSION col;
218
219 ptr = source->pub.buffer[0];
220 for (col = cinfo->image_width; col > 0; col--) {
221 (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
222 t = UCH(source->tga_pixel[0]);
223 t += UCH(source->tga_pixel[1]) << 8;
224 /* We expand 5 bit data to 8 bit sample width.
225 * The format of the 16-bit (LSB first) input word is
226 * xRRRRRGGGGGBBBBB
227 */
228 ptr[2] = (JSAMPLE) c5to8bits[t & 0x1F];
229 t >>= 5;
230 ptr[1] = (JSAMPLE) c5to8bits[t & 0x1F];
231 t >>= 5;
232 ptr[0] = (JSAMPLE) c5to8bits[t & 0x1F];
233 ptr += 3;
234 }
235 return 1;
236 }
237
238 METHODDEF(JDIMENSION)
239 get_24bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
240 /* This version is for reading 24-bit pixels */
241 {
242 tga_source_ptr source = (tga_source_ptr) sinfo;
243 register JSAMPROW ptr;
244 register JDIMENSION col;
245
246 ptr = source->pub.buffer[0];
247 for (col = cinfo->image_width; col > 0; col--) {
248 (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
249 *ptr++ = (JSAMPLE) UCH(source->tga_pixel[2]); /* change BGR to RGB order */
250 *ptr++ = (JSAMPLE) UCH(source->tga_pixel[1]);
251 *ptr++ = (JSAMPLE) UCH(source->tga_pixel[0]);
252 }
253 return 1;
254 }
255
256 /*
257 * Targa also defines a 32-bit pixel format with order B,G,R,A.
258 * We presently ignore the attribute byte, so the code for reading
259 * these pixels is identical to the 24-bit routine above.
260 * This works because the actual pixel length is only known to read_pixel.
261 */
262
263 #define get_32bit_row get_24bit_row
264
265
266 /*
267 * This method is for re-reading the input data in standard top-down
268 * row order. The entire image has already been read into whole_image
269 * with proper conversion of pixel format, but it's in a funny row order.
270 */
271
272 METHODDEF(JDIMENSION)
273 get_memory_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
274 {
275 tga_source_ptr source = (tga_source_ptr) sinfo;
276 JDIMENSION source_row;
277
278 /* Compute row of source that maps to current_row of normal order */
279 /* For now, assume image is bottom-up and not interlaced. */
280 /* NEEDS WORK to support interlaced images! */
281 source_row = cinfo->image_height - source->current_row - 1;
282
283 /* Fetch that row from virtual array */
284 source->pub.buffer = (*cinfo->mem->access_virt_sarray)
285 ((j_common_ptr) cinfo, source->whole_image,
286 source_row, (JDIMENSION) 1, FALSE);
287
288 source->current_row++;
289 return 1;
290 }
291
292
293 /*
294 * This method loads the image into whole_image during the first call on
295 * get_pixel_rows. The get_pixel_rows pointer is then adjusted to call
296 * get_memory_row on subsequent calls.
297 */
298
299 METHODDEF(JDIMENSION)
300 preload_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
301 {
302 tga_source_ptr source = (tga_source_ptr) sinfo;
303 JDIMENSION row;
304 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
305
306 /* Read the data into a virtual array in input-file row order. */
307 for (row = 0; row < cinfo->image_height; row++) {
308 if (progress != NULL) {
309 progress->pub.pass_counter = (long) row;
310 progress->pub.pass_limit = (long) cinfo->image_height;
311 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
312 }
313 source->pub.buffer = (*cinfo->mem->access_virt_sarray)
314 ((j_common_ptr) cinfo, source->whole_image, row, (JDIMENSION) 1, TRUE);
315 (*source->get_pixel_rows) (cinfo, sinfo);
316 }
317 if (progress != NULL)
318 progress->completed_extra_passes++;
319
320 /* Set up to read from the virtual array in unscrambled order */
321 source->pub.get_pixel_rows = get_memory_row;
322 source->current_row = 0;
323 /* And read the first row */
324 return get_memory_row(cinfo, sinfo);
325 }
326
327
328 /*
329 * Read the file header; return image size and component count.
330 */
331
332 METHODDEF(void)
333 start_input_tga (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
334 {
335 tga_source_ptr source = (tga_source_ptr) sinfo;
336 U_CHAR targaheader[18];
337 int idlen, cmaptype, subtype, flags, interlace_type, components;
338 unsigned int width, height, maplen;
339 boolean is_bottom_up;
340
341 #define GET_2B(offset) ((unsigned int) UCH(targaheader[offset]) + \
342 (((unsigned int) UCH(targaheader[offset+1])) << 8))
343
344 if (! ReadOK(source->pub.input_file, targaheader, 18))
345 ERREXIT(cinfo, JERR_INPUT_EOF);
346
347 /* Pretend "15-bit" pixels are 16-bit --- we ignore attribute bit anyway */
348 if (targaheader[16] == 15)
349 targaheader[16] = 16;
350
351 idlen = UCH(targaheader[0]);
352 cmaptype = UCH(targaheader[1]);
353 subtype = UCH(targaheader[2]);
354 maplen = GET_2B(5);
355 width = GET_2B(12);
356 height = GET_2B(14);
357 source->pixel_size = UCH(targaheader[16]) >> 3;
358 flags = UCH(targaheader[17]); /* Image Descriptor byte */
359
360 is_bottom_up = ((flags & 0x20) == 0); /* bit 5 set => top-down */
361 interlace_type = flags >> 6; /* bits 6/7 are interlace code */
362
363 if (cmaptype > 1 || /* cmaptype must be 0 or 1 */
364 source->pixel_size < 1 || source->pixel_size > 4 ||
365 (UCH(targaheader[16]) & 7) != 0 || /* bits/pixel must be multiple of 8 */
366 interlace_type != 0) /* currently don't allow interlaced image */
367 ERREXIT(cinfo, JERR_TGA_BADPARMS);
368
369 if (subtype > 8) {
370 /* It's an RLE-coded file */
371 source->read_pixel = read_rle_pixel;
372 source->block_count = source->dup_pixel_count = 0;
373 subtype -= 8;
374 } else {
375 /* Non-RLE file */
376 source->read_pixel = read_non_rle_pixel;
377 }
378
379 /* Now should have subtype 1, 2, or 3 */
380 components = 3; /* until proven different */
381 cinfo->in_color_space = JCS_RGB;
382
383 switch (subtype) {
384 case 1: /* Colormapped image */
385 if (source->pixel_size == 1 && cmaptype == 1)
386 source->get_pixel_rows = get_8bit_row;
387 else
388 ERREXIT(cinfo, JERR_TGA_BADPARMS);
389 TRACEMS2(cinfo, 1, JTRC_TGA_MAPPED, width, height);
390 break;
391 case 2: /* RGB image */
392 switch (source->pixel_size) {
393 case 2:
394 source->get_pixel_rows = get_16bit_row;
395 break;
396 case 3:
397 source->get_pixel_rows = get_24bit_row;
398 break;
399 case 4:
400 source->get_pixel_rows = get_32bit_row;
401 break;
402 default:
403 ERREXIT(cinfo, JERR_TGA_BADPARMS);
404 break;
405 }
406 TRACEMS2(cinfo, 1, JTRC_TGA, width, height);
407 break;
408 case 3: /* Grayscale image */
409 components = 1;
410 cinfo->in_color_space = JCS_GRAYSCALE;
411 if (source->pixel_size == 1)
412 source->get_pixel_rows = get_8bit_gray_row;
413 else
414 ERREXIT(cinfo, JERR_TGA_BADPARMS);
415 TRACEMS2(cinfo, 1, JTRC_TGA_GRAY, width, height);
416 break;
417 default:
418 ERREXIT(cinfo, JERR_TGA_BADPARMS);
419 break;
420 }
421
422 if (is_bottom_up) {
423 /* Create a virtual array to buffer the upside-down image. */
424 source->whole_image = (*cinfo->mem->request_virt_sarray)
425 ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
426 (JDIMENSION) width * components, (JDIMENSION) height, (JDIMENSION) 1);
427 if (cinfo->progress != NULL) {
428 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
429 progress->total_extra_passes++; /* count file input as separate pass */
430 }
431 /* source->pub.buffer will point to the virtual array. */
432 source->pub.buffer_height = 1; /* in case anyone looks at it */
433 source->pub.get_pixel_rows = preload_image;
434 } else {
435 /* Don't need a virtual array, but do need a one-row input buffer. */
436 source->whole_image = NULL;
437 source->pub.buffer = (*cinfo->mem->alloc_sarray)
438 ((j_common_ptr) cinfo, JPOOL_IMAGE,
439 (JDIMENSION) width * components, (JDIMENSION) 1);
440 source->pub.buffer_height = 1;
441 source->pub.get_pixel_rows = source->get_pixel_rows;
442 }
443
444 while (idlen--) /* Throw away ID field */
445 (void) read_byte(source);
446
447 if (maplen > 0) {
448 if (maplen > 256 || GET_2B(3) != 0)
449 ERREXIT(cinfo, JERR_TGA_BADCMAP);
450 /* Allocate space to store the colormap */
451 source->colormap = (*cinfo->mem->alloc_sarray)
452 ((j_common_ptr) cinfo, JPOOL_IMAGE, (JDIMENSION) maplen, (JDIMENSION) 3);
453 /* and read it from the file */
454 read_colormap(source, (int) maplen, UCH(targaheader[7]));
455 } else {
456 if (cmaptype) /* but you promised a cmap! */
457 ERREXIT(cinfo, JERR_TGA_BADPARMS);
458 source->colormap = NULL;
459 }
460
461 cinfo->input_components = components;
462 cinfo->data_precision = 8;
463 cinfo->image_width = width;
464 cinfo->image_height = height;
465 }
466
467
468 /*
469 * Finish up at the end of the file.
470 */
471
472 METHODDEF(void)
473 finish_input_tga (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
474 {
475 /* no work */
476 }
477
478
479 /*
480 * The module selection routine for Targa format input.
481 */
482
483 GLOBAL(cjpeg_source_ptr)
484 jinit_read_targa (j_compress_ptr cinfo)
485 {
486 tga_source_ptr source;
487
488 /* Create module interface object */
489 source = (tga_source_ptr)
490 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
491 SIZEOF(tga_source_struct));
492 source->cinfo = cinfo; /* make back link for subroutines */
493 /* Fill in method ptrs, except get_pixel_rows which start_input sets */
494 source->pub.start_input = start_input_tga;
495 source->pub.finish_input = finish_input_tga;
496
497 return (cjpeg_source_ptr) source;
498 }
499
500 #endif /* TARGA_SUPPORTED */