Leptonica 1.83.1
Image processing and image analysis suite
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bmpio.c
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1/*====================================================================*
2 - Copyright (C) 2001 Leptonica. All rights reserved.
3 -
4 - Redistribution and use in source and binary forms, with or without
5 - modification, are permitted provided that the following conditions
6 - are met:
7 - 1. Redistributions of source code must retain the above copyright
8 - notice, this list of conditions and the following disclaimer.
9 - 2. Redistributions in binary form must reproduce the above
10 - copyright notice, this list of conditions and the following
11 - disclaimer in the documentation and/or other materials
12 - provided with the distribution.
13 -
14 - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 - ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ANY
18 - CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 - EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 - PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 - PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 - OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
23 - NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
24 - SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *====================================================================*/
26
41
42#ifdef HAVE_CONFIG_H
43#include <config_auto.h>
44#endif /* HAVE_CONFIG_H */
45
46#include <string.h>
47#include "allheaders.h"
48#include "pix_internal.h"
49#include "bmp.h"
50
51/* --------------------------------------------*/
52#if USE_BMPIO /* defined in environ.h */
53/* --------------------------------------------*/
54
55 /* Here we're setting the pixel value 0 to white (255) and the
56 * value 1 to black (0). This is the convention for grayscale, but
57 * the opposite of the convention for 1 bpp, where 0 is white
58 * and 1 is black. Both colormap entries are opaque (alpha = 255) */
59RGBA_QUAD bwmap[2] = { {255,255,255,255}, {0,0,0,255} };
60
61 /* Image dimension limits */
62static const l_int32 L_MAX_ALLOWED_WIDTH = 1000000;
63static const l_int32 L_MAX_ALLOWED_HEIGHT = 1000000;
64static const l_int64 L_MAX_ALLOWED_PIXELS = 400000000LL;
65static const l_int32 L_MAX_ALLOWED_RES = 10000000; /* pixels/meter */
66
67#ifndef NO_CONSOLE_IO
68#define DEBUG 0
69#endif /* ~NO_CONSOLE_IO */
70
71/*--------------------------------------------------------------*
72 * Read bmp *
73 *--------------------------------------------------------------*/
87PIX *
89{
90l_uint8 *data;
91size_t size;
92PIX *pix;
93
94 if (!fp)
95 return (PIX *)ERROR_PTR("fp not defined", __func__, NULL);
96
97 /* Read data from file and decode into Y,U,V arrays */
98 rewind(fp);
99 if ((data = l_binaryReadStream(fp, &size)) == NULL)
100 return (PIX *)ERROR_PTR("data not read", __func__, NULL);
101
102 pix = pixReadMemBmp(data, size);
103 LEPT_FREE(data);
104 return pix;
105}
106
107
131PIX *
132pixReadMemBmp(const l_uint8 *cdata,
133 size_t size)
134{
135l_uint8 pel[4];
136l_uint8 *cmapBuf, *fdata, *data;
137l_int16 bftype, depth, d;
138l_int32 offset, ihbytes, width, height, height_neg, xres, yres;
139l_int32 compression, imagebytes, fdatabytes, cmapbytes, ncolors, maxcolors;
140l_int32 fdatabpl, extrabytes, pixWpl, pixBpl, i, j, k;
141l_uint32 *line, *pixdata, *pword;
142l_int64 npixels;
143BMP_FH *bmpfh;
144#if defined(__GNUC__)
145BMP_HEADER *bmph;
146#define bmpih (&bmph->bmpih)
147#else
148BMP_IH *bmpih;
149#endif
150PIX *pix, *pix1;
151PIXCMAP *cmap;
152
153 if (!cdata)
154 return (PIX *)ERROR_PTR("cdata not defined", __func__, NULL);
155 if (size < sizeof(BMP_FH) + sizeof(BMP_IH))
156 return (PIX *)ERROR_PTR("bmf size error", __func__, NULL);
157
158 /* Verify this is an uncompressed bmp */
159 bmpfh = (BMP_FH *)cdata;
160 bftype = bmpfh->bfType[0] + ((l_int32)bmpfh->bfType[1] << 8);
161 if (bftype != BMP_ID)
162 return (PIX *)ERROR_PTR("not bmf format", __func__, NULL);
163#if defined(__GNUC__)
164 bmph = (BMP_HEADER *)bmpfh;
165#else
166 bmpih = (BMP_IH *)(cdata + BMP_FHBYTES);
167#endif
168 compression = convertOnBigEnd32(bmpih->biCompression);
169 if (compression != 0)
170 return (PIX *)ERROR_PTR("cannot read compressed BMP files",
171 __func__, NULL);
172
173 /* Find the offset from the beginning of the file to the image data */
174 offset = bmpfh->bfOffBits[0];
175 offset += (l_int32)bmpfh->bfOffBits[1] << 8;
176 offset += (l_int32)bmpfh->bfOffBits[2] << 16;
177 offset += (l_uint32)bmpfh->bfOffBits[3] << 24;
178
179 /* Read the remaining useful data in the infoheader.
180 * Note that the first 4 bytes give the infoheader size. */
181 ihbytes = convertOnBigEnd32(*(l_uint32 *)(bmpih));
182 width = convertOnBigEnd32(bmpih->biWidth);
183 height = convertOnBigEnd32(bmpih->biHeight);
184 depth = convertOnBigEnd16(bmpih->biBitCount);
185 imagebytes = convertOnBigEnd32(bmpih->biSizeImage);
186 xres = convertOnBigEnd32(bmpih->biXPelsPerMeter);
187 yres = convertOnBigEnd32(bmpih->biYPelsPerMeter);
188
189 /* Some sanity checking. We impose limits on the image
190 * dimensions, resolution and number of pixels. We make sure the
191 * file is the correct size to hold the amount of uncompressed data
192 * that is specified in the header. The number of colormap
193 * entries is checked: it can be either 0 (no cmap) or some
194 * number between 2 and 256.
195 * Note that the imagebytes for uncompressed images is either
196 * 0 or the size of the file data. (The fact that it can
197 * be 0 is perhaps some legacy glitch). */
198 if (width < 1)
199 return (PIX *)ERROR_PTR("width < 1", __func__, NULL);
200 if (width > L_MAX_ALLOWED_WIDTH)
201 return (PIX *)ERROR_PTR("width too large", __func__, NULL);
202 if (height == 0 || height < -L_MAX_ALLOWED_HEIGHT ||
203 height > L_MAX_ALLOWED_HEIGHT)
204 return (PIX *)ERROR_PTR("invalid height", __func__, NULL);
205 if (xres < 0 || xres > L_MAX_ALLOWED_RES ||
206 yres < 0 || yres > L_MAX_ALLOWED_RES)
207 return (PIX *)ERROR_PTR("invalid resolution", __func__, NULL);
208 height_neg = 0;
209 if (height < 0) {
210 height_neg = 1;
211 height = -height;
212 }
213 if (ihbytes != 40 && ihbytes != 108 && ihbytes != 124) {
214 L_ERROR("invalid ihbytes = %d; not in {40, 108, 124}\n",
215 __func__, ihbytes);
216 return NULL;
217 }
218 npixels = 1LL * width * height;
219 if (npixels > L_MAX_ALLOWED_PIXELS)
220 return (PIX *)ERROR_PTR("npixels too large", __func__, NULL);
221 if (depth == 32)
222 return (PIX *)ERROR_PTR("32 bpp rgba input data is not supported",
223 __func__, NULL);
224 if (depth != 1 && depth != 2 && depth != 4 && depth != 8 &&
225 depth != 16 && depth != 24) {
226 L_ERROR("invalid depth = %d; not in {1, 2, 4, 8, 16, 24}\n",
227 __func__, depth);
228 return NULL;
229 }
230 fdatabpl = 4 * ((1LL * width * depth + 31)/32);
231 fdatabytes = fdatabpl * height;
232 if (imagebytes != 0 && imagebytes != fdatabytes) {
233 L_ERROR("invalid imagebytes = %d; not equal to fdatabytes = %d\n",
234 __func__, imagebytes, fdatabytes);
235 return NULL;
236 }
237
238 /* In the original spec, BITMAPINFOHEADER is 40 bytes.
239 * There have been a number of revisions, to capture more information.
240 * For example, the fifth version, BITMAPV5HEADER, adds 84 bytes
241 * of ICC color profiles. We use the size of the infoheader
242 * to accommodate these newer formats. Knowing the size of the
243 * infoheader gives more opportunity to sanity check input params. */
244 cmapbytes = offset - BMP_FHBYTES - ihbytes;
245 ncolors = cmapbytes / sizeof(RGBA_QUAD);
246 if (ncolors < 0 || ncolors == 1)
247 return (PIX *)ERROR_PTR("invalid: cmap size < 0 or 1", __func__, NULL);
248 if (ncolors > 0 && depth > 8)
249 return (PIX *)ERROR_PTR("can't have cmap for d > 8", __func__, NULL);
250 maxcolors = (depth <= 8) ? 1 << depth : 0;
251 if (ncolors > maxcolors) {
252 L_ERROR("cmap too large for depth %d: ncolors = %d > maxcolors = %d\n",
253 __func__, depth, ncolors, maxcolors);
254 return NULL;
255 }
256 if (size != 1LL * offset + 1LL * fdatabytes)
257 return (PIX *)ERROR_PTR("size incommensurate with image data",
258 __func__,NULL);
259
260 /* Handle the colormap */
261 cmapBuf = NULL;
262 if (ncolors > 0) {
263 if ((cmapBuf = (l_uint8 *)LEPT_CALLOC(ncolors, sizeof(RGBA_QUAD)))
264 == NULL)
265 return (PIX *)ERROR_PTR("cmapBuf alloc fail", __func__, NULL );
266
267 /* Read the colormap entry data from bmp. The RGBA_QUAD colormap
268 * entries are used for both bmp and leptonica colormaps. */
269 memcpy(cmapBuf, cdata + BMP_FHBYTES + ihbytes,
270 ncolors * sizeof(RGBA_QUAD));
271 }
272
273 /* Make a 32 bpp pix if depth is 24 bpp */
274 d = (depth == 24) ? 32 : depth;
275 if ((pix = pixCreate(width, height, d)) == NULL) {
276 LEPT_FREE(cmapBuf);
277 return (PIX *)ERROR_PTR( "pix not made", __func__, NULL);
278 }
279 pixSetXRes(pix, (l_int32)((l_float32)xres / 39.37 + 0.5)); /* to ppi */
280 pixSetYRes(pix, (l_int32)((l_float32)yres / 39.37 + 0.5)); /* to ppi */
281 pixSetInputFormat(pix, IFF_BMP);
282 pixWpl = pixGetWpl(pix);
283 pixBpl = 4 * pixWpl;
284
285 /* Convert the bmp colormap to a pixcmap */
286 cmap = NULL;
287 if (ncolors > 0) { /* import the colormap to the pix cmap */
288 cmap = pixcmapCreate(L_MIN(d, 8));
289 LEPT_FREE(cmap->array); /* remove generated cmap array */
290 cmap->array = (void *)cmapBuf; /* and replace */
291 cmap->n = L_MIN(ncolors, 256);
292 for (i = 0; i < cmap->n; i++) /* set all colors opaque */
293 pixcmapSetAlpha (cmap, i, 255);
294 }
295 if (pixSetColormap(pix, cmap)) {
296 pixDestroy(&pix);
297 return (PIX *)ERROR_PTR("invalid colormap", __func__, NULL);
298 }
299
300 /* Acquire the image data. Image origin for bmp is at lower right. */
301 fdata = (l_uint8 *)cdata + offset; /* start of the bmp image data */
302 pixdata = pixGetData(pix);
303 if (depth != 24) { /* typ. 1 or 8 bpp */
304 data = (l_uint8 *)pixdata + pixBpl * (height - 1);
305 for (i = 0; i < height; i++) {
306 memcpy(data, fdata, fdatabpl);
307 fdata += fdatabpl;
308 data -= pixBpl;
309 }
310 } else { /* 24 bpp file; 32 bpp pix
311 * Note: for bmp files, pel[0] is blue, pel[1] is green,
312 * and pel[2] is red. This is opposite to the storage
313 * in the pix, which puts the red pixel in the 0 byte,
314 * the green in the 1 byte and the blue in the 2 byte.
315 * Note also that all words are endian flipped after
316 * assignment on L_LITTLE_ENDIAN platforms.
317 *
318 * We can then make these assignments for little endians:
319 * SET_DATA_BYTE(pword, 1, pel[0]); blue
320 * SET_DATA_BYTE(pword, 2, pel[1]); green
321 * SET_DATA_BYTE(pword, 3, pel[2]); red
322 * This looks like:
323 * 3 (R) 2 (G) 1 (B) 0
324 * |-----------|------------|-----------|-----------|
325 * and after byte flipping:
326 * 3 2 (B) 1 (G) 0 (R)
327 * |-----------|------------|-----------|-----------|
328 *
329 * For big endians we set:
330 * SET_DATA_BYTE(pword, 2, pel[0]); blue
331 * SET_DATA_BYTE(pword, 1, pel[1]); green
332 * SET_DATA_BYTE(pword, 0, pel[2]); red
333 * This looks like:
334 * 0 (R) 1 (G) 2 (B) 3
335 * |-----------|------------|-----------|-----------|
336 * so in both cases we get the correct assignment in the PIX.
337 *
338 * Can we do a platform-independent assignment?
339 * Yes, set the bytes without using macros:
340 * *((l_uint8 *)pword) = pel[2]; red
341 * *((l_uint8 *)pword + 1) = pel[1]; green
342 * *((l_uint8 *)pword + 2) = pel[0]; blue
343 * For little endians, before flipping, this looks again like:
344 * 3 (R) 2 (G) 1 (B) 0
345 * |-----------|------------|-----------|-----------|
346 */
347 extrabytes = fdatabpl - 3 * width;
348 line = pixdata + pixWpl * (height - 1);
349 for (i = 0; i < height; i++) {
350 for (j = 0; j < width; j++) {
351 pword = line + j;
352 memcpy(&pel, fdata, 3);
353 fdata += 3;
354 *((l_uint8 *)pword + COLOR_RED) = pel[2];
355 *((l_uint8 *)pword + COLOR_GREEN) = pel[1];
356 *((l_uint8 *)pword + COLOR_BLUE) = pel[0];
357 /* should not use alpha byte, but for buggy readers,
358 * set it to opaque */
359 *((l_uint8 *)pword + L_ALPHA_CHANNEL) = 255;
360 }
361 if (extrabytes) {
362 for (k = 0; k < extrabytes; k++) {
363 memcpy(&pel, fdata, 1);
364 fdata++;
365 }
366 }
367 line -= pixWpl;
368 }
369 }
370
371 pixEndianByteSwap(pix);
372 if (height_neg)
373 pixFlipTB(pix, pix);
374
375 /* ----------------------------------------------
376 * We do not use 1 bpp pix with colormaps in leptonica.
377 * The colormap must be removed in such a way that the pixel
378 * values are not changed. If the values are only black and
379 * white, return a 1 bpp image; if gray, return an 8 bpp pix;
380 * otherwise, return a 32 bpp rgb pix.
381 * ---------------------------------------------- */
382 if (depth == 1 && cmap) {
383 L_INFO("removing opaque cmap from 1 bpp\n", __func__);
384 pix1 = pixRemoveColormap(pix, REMOVE_CMAP_BASED_ON_SRC);
385 pixDestroy(&pix);
386 pix = pix1; /* rename */
387 }
388
389 return pix;
390}
391
392
393/*--------------------------------------------------------------*
394 * Write bmp *
395 *--------------------------------------------------------------*/
403l_ok
405 PIX *pix)
406{
407l_uint8 *data;
408size_t size, nbytes;
409
410 if (!fp)
411 return ERROR_INT("stream not defined", __func__, 1);
412 if (!pix)
413 return ERROR_INT("pix not defined", __func__, 1);
414
415 pixWriteMemBmp(&data, &size, pix);
416 rewind(fp);
417 nbytes = fwrite(data, 1, size, fp);
418 free(data);
419 if (nbytes != size)
420 return ERROR_INT("Write error", __func__, 1);
421 return 0;
422}
423
424
446l_ok
447pixWriteMemBmp(l_uint8 **pfdata,
448 size_t *pfsize,
449 PIX *pixs)
450{
451l_uint8 pel[4];
452l_uint8 *cta = NULL; /* address of the bmp color table array */
453l_uint8 *fdata, *data, *fmdata;
454l_int32 cmaplen; /* number of bytes in the bmp colormap */
455l_int32 ncolors, val, stepsize, w, h, d, fdepth, xres, yres, valid;
456l_int32 pixWpl, pixBpl, extrabytes, fBpl, fWpl, i, j, k;
457l_int32 heapcm; /* extra copy of cta on the heap ? 1 : 0 */
458l_uint32 offbytes, fimagebytes;
459l_uint32 *line, *pword;
460size_t fsize;
461BMP_FH *bmpfh;
462#if defined(__GNUC__)
463BMP_HEADER *bmph;
464#define bmpih (&bmph->bmpih)
465#else
466BMP_IH *bmpih;
467#endif
468PIX *pix;
469PIXCMAP *cmap;
470RGBA_QUAD *pquad;
471
472 if (pfdata) *pfdata = NULL;
473 if (pfsize) *pfsize = 0;
474 if (!pfdata)
475 return ERROR_INT("&fdata not defined", __func__, 1 );
476 if (!pfsize)
477 return ERROR_INT("&fsize not defined", __func__, 1 );
478 if (!pixs)
479 return ERROR_INT("pixs not defined", __func__, 1);
480
481 /* Verify validity of colormap */
482 if ((cmap = pixGetColormap(pixs)) != NULL) {
483 pixcmapIsValid(cmap, pixs, &valid);
484 if (!valid)
485 return ERROR_INT("colormap is not valid", __func__, 1);
486 }
487
488 pixGetDimensions(pixs, &w, &h, &d);
489 if (d == 2) {
490 L_WARNING("2 bpp files can't be read; converting to 8 bpp\n", __func__);
491 pix = pixConvert2To8(pixs, 0, 85, 170, 255, 1);
492 d = 8;
493 } else {
494 pix = pixCopy(NULL, pixs);
495 }
496 if (pixGetSpp(pixs) == 4)
497 L_WARNING("transparency component for rgba pix is ignored; "
498 "assumed opaque\n", __func__);
499 fdepth = (d == 32) ? 24 : d;
500
501 /* Resolution is given in pixels/meter */
502 xres = (l_int32)(39.37 * (l_float32)pixGetXRes(pix) + 0.5);
503 yres = (l_int32)(39.37 * (l_float32)pixGetYRes(pix) + 0.5);
504
505 pixWpl = pixGetWpl(pix);
506 pixBpl = 4 * pixWpl;
507 fWpl = (w * fdepth + 31) / 32;
508 fBpl = 4 * fWpl;
509 fimagebytes = h * fBpl;
510 if (fimagebytes > 4LL * L_MAX_ALLOWED_PIXELS) {
511 pixDestroy(&pix);
512 return ERROR_INT("image data is too large", __func__, 1);
513 }
514
515 /* If not rgb or 16 bpp, the bmp data is required to have a colormap */
516 heapcm = 0;
517 if (d == 32 || d == 16) { /* 24 bpp rgb or 16 bpp: no colormap */
518 ncolors = 0;
519 cmaplen = 0;
520 } else if ((cmap = pixGetColormap(pix))) { /* existing colormap */
521 ncolors = pixcmapGetCount(cmap);
522 cmaplen = ncolors * sizeof(RGBA_QUAD);
523 cta = (l_uint8 *)cmap->array;
524 } else { /* no existing colormap; d <= 8; make a binary or gray one */
525 if (d == 1) {
526 cmaplen = sizeof(bwmap);
527 ncolors = 2;
528 cta = (l_uint8 *)bwmap;
529 } else { /* d = 2,4,8; use a grayscale output colormap */
530 ncolors = 1 << fdepth;
531 cmaplen = ncolors * sizeof(RGBA_QUAD);
532 heapcm = 1;
533 cta = (l_uint8 *)LEPT_CALLOC(cmaplen, 1);
534 stepsize = 255 / (ncolors - 1);
535 for (i = 0, val = 0, pquad = (RGBA_QUAD *)cta;
536 i < ncolors;
537 i++, val += stepsize, pquad++) {
538 pquad->blue = pquad->green = pquad->red = val;
539 pquad->alpha = 255; /* opaque */
540 }
541 }
542 }
543
544#if DEBUG
545 {l_uint8 *pcmptr;
546 pcmptr = (l_uint8 *)pixGetColormap(pix)->array;
547 lept_stderr("Pix colormap[0] = %c%c%c%d\n",
548 pcmptr[0], pcmptr[1], pcmptr[2], pcmptr[3]);
549 lept_stderr("Pix colormap[1] = %c%c%c%d\n",
550 pcmptr[4], pcmptr[5], pcmptr[6], pcmptr[7]);
551 }
552#endif /* DEBUG */
553
554 offbytes = BMP_FHBYTES + BMP_IHBYTES + cmaplen;
555 fsize = offbytes + fimagebytes;
556 fdata = (l_uint8 *)LEPT_CALLOC(fsize, 1);
557 *pfdata = fdata;
558 *pfsize = fsize;
559
560 /* Write little-endian file header data */
561 bmpfh = (BMP_FH *)fdata;
562 bmpfh->bfType[0] = (l_uint8)(BMP_ID >> 0);
563 bmpfh->bfType[1] = (l_uint8)(BMP_ID >> 8);
564 bmpfh->bfSize[0] = (l_uint8)(fsize >> 0);
565 bmpfh->bfSize[1] = (l_uint8)(fsize >> 8);
566 bmpfh->bfSize[2] = (l_uint8)(fsize >> 16);
567 bmpfh->bfSize[3] = (l_uint8)(fsize >> 24);
568 bmpfh->bfOffBits[0] = (l_uint8)(offbytes >> 0);
569 bmpfh->bfOffBits[1] = (l_uint8)(offbytes >> 8);
570 bmpfh->bfOffBits[2] = (l_uint8)(offbytes >> 16);
571 bmpfh->bfOffBits[3] = (l_uint8)(offbytes >> 24);
572
573 /* Convert to little-endian and write the info header data */
574#if defined(__GNUC__)
575 bmph = (BMP_HEADER *)bmpfh;
576#else
577 bmpih = (BMP_IH *)(fdata + BMP_FHBYTES);
578#endif
579 bmpih->biSize = convertOnBigEnd32(BMP_IHBYTES);
580 bmpih->biWidth = convertOnBigEnd32(w);
581 bmpih->biHeight = convertOnBigEnd32(h);
582 bmpih->biPlanes = convertOnBigEnd16(1);
583 bmpih->biBitCount = convertOnBigEnd16(fdepth);
584 bmpih->biSizeImage = convertOnBigEnd32(fimagebytes);
585 bmpih->biXPelsPerMeter = convertOnBigEnd32(xres);
586 bmpih->biYPelsPerMeter = convertOnBigEnd32(yres);
587 bmpih->biClrUsed = convertOnBigEnd32(ncolors);
588 bmpih->biClrImportant = convertOnBigEnd32(ncolors);
589
590 /* Copy the colormap data and free the cta if necessary */
591 if (ncolors > 0) {
592 memcpy(fdata + BMP_FHBYTES + BMP_IHBYTES, cta, cmaplen);
593 if (heapcm) LEPT_FREE(cta);
594 }
595
596 /* When you write a binary image with a colormap
597 * that sets BLACK to 0, you must invert the data */
598 if (fdepth == 1 && cmap && ((l_uint8 *)(cmap->array))[0] == 0x0) {
599 pixInvert(pix, pix);
600 }
601
602 /* An endian byte swap is also required */
603 pixEndianByteSwap(pix);
604
605 /* Transfer the image data. Image origin for bmp is at lower right. */
606 fmdata = fdata + offbytes;
607 if (fdepth != 24) { /* typ 1 or 8 bpp */
608 data = (l_uint8 *)pixGetData(pix) + pixBpl * (h - 1);
609 for (i = 0; i < h; i++) {
610 memcpy(fmdata, data, fBpl);
611 data -= pixBpl;
612 fmdata += fBpl;
613 }
614 } else { /* 32 bpp pix; 24 bpp file
615 * See the comments in pixReadStreamBmp() to
616 * understand the logic behind the pixel ordering below.
617 * Note that we have again done an endian swap on
618 * little endian machines before arriving here, so that
619 * the bytes are ordered on both platforms as:
620 Red Green Blue --
621 |-----------|------------|-----------|-----------|
622 */
623 extrabytes = fBpl - 3 * w;
624 line = pixGetData(pix) + pixWpl * (h - 1);
625 for (i = 0; i < h; i++) {
626 for (j = 0; j < w; j++) {
627 pword = line + j;
628 pel[2] = *((l_uint8 *)pword + COLOR_RED);
629 pel[1] = *((l_uint8 *)pword + COLOR_GREEN);
630 pel[0] = *((l_uint8 *)pword + COLOR_BLUE);
631 memcpy(fmdata, &pel, 3);
632 fmdata += 3;
633 }
634 if (extrabytes) {
635 for (k = 0; k < extrabytes; k++) {
636 memcpy(fmdata, &pel, 1);
637 fmdata++;
638 }
639 }
640 line -= pixWpl;
641 }
642 }
643
644 pixDestroy(&pix);
645 return 0;
646}
647
648/* --------------------------------------------*/
649#endif /* USE_BMPIO */
#define BMP_IHBYTES
Definition bmp.h:108
#define BMP_FHBYTES
Definition bmp.h:83
l_ok pixWriteStreamBmp(FILE *fp, PIX *pix)
pixWriteStreamBmp()
Definition bmpio.c:404
PIX * pixReadStreamBmp(FILE *fp)
pixReadStreamBmp()
Definition bmpio.c:88
l_ok pixWriteMemBmp(l_uint8 **pfdata, size_t *pfsize, PIX *pixs)
pixWriteMemBmp()
Definition bmpio.c:447
PIX * pixReadMemBmp(const l_uint8 *cdata, size_t size)
pixReadMemBmp()
Definition bmpio.c:132
@ BMP_ID
Definition imageio.h:126
@ REMOVE_CMAP_BASED_ON_SRC
Definition pix.h:384
struct Pix PIX
Definition pix.h:228
struct PixColormap PIXCMAP
Definition pix.h:231
struct RGBA_Quad RGBA_QUAD
Definition pix.h:237
@ COLOR_BLUE
Definition pix.h:330
@ COLOR_RED
Definition pix.h:328
@ L_ALPHA_CHANNEL
Definition pix.h:331
@ COLOR_GREEN
Definition pix.h:329
l_uint8 bfOffBits[4]
Definition bmp.h:78
l_uint8 bfSize[4]
Definition bmp.h:70
l_uint8 bfType[2]
Definition bmp.h:69
l_int32 biSizeImage
Definition bmp.h:99
l_int32 biXPelsPerMeter
Definition bmp.h:100
l_int32 biClrImportant
Definition bmp.h:103
l_int32 biClrUsed
Definition bmp.h:102
l_int32 biSize
Definition bmp.h:93
l_int32 biYPelsPerMeter
Definition bmp.h:101
l_int16 biPlanes
Definition bmp.h:96
l_int32 biWidth
Definition bmp.h:94
l_int16 biBitCount
Definition bmp.h:97
l_int32 biHeight
Definition bmp.h:95
l_int32 biCompression
Definition bmp.h:98
l_uint8 alpha
l_uint8 green
l_uint8 blue
l_uint8 red