1/* 2 * rdbmp.c 3 * 4 * Copyright (C) 1994-1996, Thomas G. Lane. 5 * Modified 2009-2010 by Guido Vollbeding. 6 * This file is part of the Independent JPEG Group's software. 7 * For conditions of distribution and use, see the accompanying README file. 8 * 9 * This file contains routines to read input images in Microsoft "BMP" 10 * format (MS Windows 3.x, OS/2 1.x, and OS/2 2.x flavors). 11 * Currently, only 8-bit and 24-bit images are supported, not 1-bit or 12 * 4-bit (feeding such low-depth images into JPEG would be silly anyway). 13 * Also, we don't support RLE-compressed files. 14 * 15 * These routines may need modification for non-Unix environments or 16 * specialized applications. As they stand, they assume input from 17 * an ordinary stdio stream. They further assume that reading begins 18 * at the start of the file; start_input may need work if the 19 * user interface has already read some data (e.g., to determine that 20 * the file is indeed BMP format). 21 * 22 * This code contributed by James Arthur Boucher. 23 */ 24 25#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */ 26 27#ifdef BMP_SUPPORTED 28 29 30/* Macros to deal with unsigned chars as efficiently as compiler allows */ 31 32#ifdef HAVE_UNSIGNED_CHAR 33typedef unsigned char U_CHAR; 34#define UCH(x) ((int) (x)) 35#else /* !HAVE_UNSIGNED_CHAR */ 36#ifdef CHAR_IS_UNSIGNED 37typedef char U_CHAR; 38#define UCH(x) ((int) (x)) 39#else 40typedef char U_CHAR; 41#define UCH(x) ((int) (x) & 0xFF) 42#endif 43#endif /* HAVE_UNSIGNED_CHAR */ 44 45 46#define ReadOK(file,buffer,len) (JFREAD(file,buffer,len) == ((size_t) (len))) 47 48 49/* Private version of data source object */ 50 51typedef struct _bmp_source_struct * bmp_source_ptr; 52 53typedef struct _bmp_source_struct { 54 struct cjpeg_source_struct pub; /* public fields */ 55 56 j_compress_ptr cinfo; /* back link saves passing separate parm */ 57 58 JSAMPARRAY colormap; /* BMP colormap (converted to my format) */ 59 60 jvirt_sarray_ptr whole_image; /* Needed to reverse row order */ 61 JDIMENSION source_row; /* Current source row number */ 62 JDIMENSION row_width; /* Physical width of scanlines in file */ 63 64 int bits_per_pixel; /* remembers 8- or 24-bit format */ 65} bmp_source_struct; 66 67 68LOCAL(int) 69read_byte (bmp_source_ptr sinfo) 70/* Read next byte from BMP file */ 71{ 72 register FILE *infile = sinfo->pub.input_file; 73 register int c; 74 75 if ((c = getc(infile)) == EOF) 76 ERREXIT(sinfo->cinfo, JERR_INPUT_EOF); 77 return c; 78} 79 80 81LOCAL(void) 82read_colormap (bmp_source_ptr sinfo, int cmaplen, int mapentrysize) 83/* Read the colormap from a BMP file */ 84{ 85 int i; 86 87 switch (mapentrysize) { 88 case 3: 89 /* BGR format (occurs in OS/2 files) */ 90 for (i = 0; i < cmaplen; i++) { 91 sinfo->colormap[2][i] = (JSAMPLE) read_byte(sinfo); 92 sinfo->colormap[1][i] = (JSAMPLE) read_byte(sinfo); 93 sinfo->colormap[0][i] = (JSAMPLE) read_byte(sinfo); 94 } 95 break; 96 case 4: 97 /* BGR0 format (occurs in MS Windows files) */ 98 for (i = 0; i < cmaplen; i++) { 99 sinfo->colormap[2][i] = (JSAMPLE) read_byte(sinfo); 100 sinfo->colormap[1][i] = (JSAMPLE) read_byte(sinfo); 101 sinfo->colormap[0][i] = (JSAMPLE) read_byte(sinfo); 102 (void) read_byte(sinfo); 103 } 104 break; 105 default: 106 ERREXIT(sinfo->cinfo, JERR_BMP_BADCMAP); 107 break; 108 } 109} 110 111 112/* 113 * Read one row of pixels. 114 * The image has been read into the whole_image array, but is otherwise 115 * unprocessed. We must read it out in top-to-bottom row order, and if 116 * it is an 8-bit image, we must expand colormapped pixels to 24bit format. 117 */ 118 119METHODDEF(JDIMENSION) 120get_8bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) 121/* This version is for reading 8-bit colormap indexes */ 122{ 123 bmp_source_ptr source = (bmp_source_ptr) sinfo; 124 register JSAMPARRAY colormap = source->colormap; 125 JSAMPARRAY image_ptr; 126 register int t; 127 register JSAMPROW inptr, outptr; 128 register JDIMENSION col; 129 130 /* Fetch next row from virtual array */ 131 source->source_row--; 132 image_ptr = (*cinfo->mem->access_virt_sarray) 133 ((j_common_ptr) cinfo, source->whole_image, 134 source->source_row, (JDIMENSION) 1, FALSE); 135 136 /* Expand the colormap indexes to real data */ 137 inptr = image_ptr[0]; 138 outptr = source->pub.buffer[0]; 139 for (col = cinfo->image_width; col > 0; col--) { 140 t = GETJSAMPLE(*inptr++); 141 *outptr++ = colormap[0][t]; /* can omit GETJSAMPLE() safely */ 142 *outptr++ = colormap[1][t]; 143 *outptr++ = colormap[2][t]; 144 } 145 146 return 1; 147} 148 149 150METHODDEF(JDIMENSION) 151get_24bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) 152/* This version is for reading 24-bit pixels */ 153{ 154 bmp_source_ptr source = (bmp_source_ptr) sinfo; 155 JSAMPARRAY image_ptr; 156 register JSAMPROW inptr, outptr; 157 register JDIMENSION col; 158 159 /* Fetch next row from virtual array */ 160 source->source_row--; 161 image_ptr = (*cinfo->mem->access_virt_sarray) 162 ((j_common_ptr) cinfo, source->whole_image, 163 source->source_row, (JDIMENSION) 1, FALSE); 164 165 /* Transfer data. Note source values are in BGR order 166 * (even though Microsoft's own documents say the opposite). 167 */ 168 inptr = image_ptr[0]; 169 outptr = source->pub.buffer[0]; 170 for (col = cinfo->image_width; col > 0; col--) { 171 outptr[2] = *inptr++; /* can omit GETJSAMPLE() safely */ 172 outptr[1] = *inptr++; 173 outptr[0] = *inptr++; 174 outptr += 3; 175 } 176 177 return 1; 178} 179 180 181METHODDEF(JDIMENSION) 182get_32bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) 183/* This version is for reading 32-bit pixels */ 184{ 185 bmp_source_ptr source = (bmp_source_ptr) sinfo; 186 JSAMPARRAY image_ptr; 187 register JSAMPROW inptr, outptr; 188 register JDIMENSION col; 189 190 /* Fetch next row from virtual array */ 191 source->source_row--; 192 image_ptr = (*cinfo->mem->access_virt_sarray) 193 ((j_common_ptr) cinfo, source->whole_image, 194 source->source_row, (JDIMENSION) 1, FALSE); 195 /* Transfer data. Note source values are in BGR order 196 * (even though Microsoft's own documents say the opposite). 197 */ 198 inptr = image_ptr[0]; 199 outptr = source->pub.buffer[0]; 200 for (col = cinfo->image_width; col > 0; col--) { 201 outptr[2] = *inptr++; /* can omit GETJSAMPLE() safely */ 202 outptr[1] = *inptr++; 203 outptr[0] = *inptr++; 204 inptr++; /* skip the 4th byte (Alpha channel) */ 205 outptr += 3; 206 } 207 208 return 1; 209} 210 211 212/* 213 * This method loads the image into whole_image during the first call on 214 * get_pixel_rows. The get_pixel_rows pointer is then adjusted to call 215 * get_8bit_row, get_24bit_row, or get_32bit_row on subsequent calls. 216 */ 217 218METHODDEF(JDIMENSION) 219preload_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) 220{ 221 bmp_source_ptr source = (bmp_source_ptr) sinfo; 222 register FILE *infile = source->pub.input_file; 223 register int c; 224 register JSAMPROW out_ptr; 225 JSAMPARRAY image_ptr; 226 JDIMENSION row, col; 227 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; 228 229 /* Read the data into a virtual array in input-file row order. */ 230 for (row = 0; row < cinfo->image_height; row++) { 231 if (progress != NULL) { 232 progress->pub.pass_counter = (long) row; 233 progress->pub.pass_limit = (long) cinfo->image_height; 234 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); 235 } 236 image_ptr = (*cinfo->mem->access_virt_sarray) 237 ((j_common_ptr) cinfo, source->whole_image, 238 row, (JDIMENSION) 1, TRUE); 239 out_ptr = image_ptr[0]; 240 for (col = source->row_width; col > 0; col--) { 241 /* inline copy of read_byte() for speed */ 242 if ((c = getc(infile)) == EOF) 243 ERREXIT(cinfo, JERR_INPUT_EOF); 244 *out_ptr++ = (JSAMPLE) c; 245 } 246 } 247 if (progress != NULL) 248 progress->completed_extra_passes++; 249 250 /* Set up to read from the virtual array in top-to-bottom order */ 251 switch (source->bits_per_pixel) { 252 case 8: 253 source->pub.get_pixel_rows = get_8bit_row; 254 break; 255 case 24: 256 source->pub.get_pixel_rows = get_24bit_row; 257 break; 258 case 32: 259 source->pub.get_pixel_rows = get_32bit_row; 260 break; 261 default: 262 ERREXIT(cinfo, JERR_BMP_BADDEPTH); 263 } 264 source->source_row = cinfo->image_height; 265 266 /* And read the first row */ 267 return (*source->pub.get_pixel_rows) (cinfo, sinfo); 268} 269 270 271/* 272 * Read the file header; return image size and component count. 273 */ 274 275METHODDEF(void) 276start_input_bmp (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) 277{ 278 bmp_source_ptr source = (bmp_source_ptr) sinfo; 279 U_CHAR bmpfileheader[14]; 280 U_CHAR bmpinfoheader[64]; 281#define GET_2B(array,offset) ((unsigned int) UCH(array[offset]) + \ 282 (((unsigned int) UCH(array[offset+1])) << 8)) 283#define GET_4B(array,offset) ((INT32) UCH(array[offset]) + \ 284 (((INT32) UCH(array[offset+1])) << 8) + \ 285 (((INT32) UCH(array[offset+2])) << 16) + \ 286 (((INT32) UCH(array[offset+3])) << 24)) 287 INT32 bfOffBits; 288 INT32 headerSize; 289 INT32 biWidth; 290 INT32 biHeight; 291 unsigned int biPlanes; 292 INT32 biCompression; 293 INT32 biXPelsPerMeter,biYPelsPerMeter; 294 INT32 biClrUsed = 0; 295 int mapentrysize = 0; /* 0 indicates no colormap */ 296 INT32 bPad; 297 JDIMENSION row_width; 298 299 /* Read and verify the bitmap file header */ 300 if (! ReadOK(source->pub.input_file, bmpfileheader, 14)) 301 ERREXIT(cinfo, JERR_INPUT_EOF); 302 if (GET_2B(bmpfileheader,0) != 0x4D42) /* 'BM' */ 303 ERREXIT(cinfo, JERR_BMP_NOT); 304 bfOffBits = (INT32) GET_4B(bmpfileheader,10); 305 /* We ignore the remaining fileheader fields */ 306 307 /* The infoheader might be 12 bytes (OS/2 1.x), 40 bytes (Windows), 308 * or 64 bytes (OS/2 2.x). Check the first 4 bytes to find out which. 309 */ 310 if (! ReadOK(source->pub.input_file, bmpinfoheader, 4)) 311 ERREXIT(cinfo, JERR_INPUT_EOF); 312 headerSize = (INT32) GET_4B(bmpinfoheader,0); 313 if (headerSize < 12 || headerSize > 64) 314 ERREXIT(cinfo, JERR_BMP_BADHEADER); 315 if (! ReadOK(source->pub.input_file, bmpinfoheader+4, headerSize-4)) 316 ERREXIT(cinfo, JERR_INPUT_EOF); 317 318 switch ((int) headerSize) { 319 case 12: 320 /* Decode OS/2 1.x header (Microsoft calls this a BITMAPCOREHEADER) */ 321 biWidth = (INT32) GET_2B(bmpinfoheader,4); 322 biHeight = (INT32) GET_2B(bmpinfoheader,6); 323 biPlanes = GET_2B(bmpinfoheader,8); 324 source->bits_per_pixel = (int) GET_2B(bmpinfoheader,10); 325 326 switch (source->bits_per_pixel) { 327 case 8: /* colormapped image */ 328 mapentrysize = 3; /* OS/2 uses RGBTRIPLE colormap */ 329 TRACEMS2(cinfo, 1, JTRC_BMP_OS2_MAPPED, (int) biWidth, (int) biHeight); 330 break; 331 case 24: /* RGB image */ 332 TRACEMS2(cinfo, 1, JTRC_BMP_OS2, (int) biWidth, (int) biHeight); 333 break; 334 default: 335 ERREXIT(cinfo, JERR_BMP_BADDEPTH); 336 break; 337 } 338 break; 339 case 40: 340 case 64: 341 /* Decode Windows 3.x header (Microsoft calls this a BITMAPINFOHEADER) */ 342 /* or OS/2 2.x header, which has additional fields that we ignore */ 343 biWidth = GET_4B(bmpinfoheader,4); 344 biHeight = GET_4B(bmpinfoheader,8); 345 biPlanes = GET_2B(bmpinfoheader,12); 346 source->bits_per_pixel = (int) GET_2B(bmpinfoheader,14); 347 biCompression = GET_4B(bmpinfoheader,16); 348 biXPelsPerMeter = GET_4B(bmpinfoheader,24); 349 biYPelsPerMeter = GET_4B(bmpinfoheader,28); 350 biClrUsed = GET_4B(bmpinfoheader,32); 351 /* biSizeImage, biClrImportant fields are ignored */ 352 353 switch (source->bits_per_pixel) { 354 case 8: /* colormapped image */ 355 mapentrysize = 4; /* Windows uses RGBQUAD colormap */ 356 TRACEMS2(cinfo, 1, JTRC_BMP_MAPPED, (int) biWidth, (int) biHeight); 357 break; 358 case 24: /* RGB image */ 359 TRACEMS2(cinfo, 1, JTRC_BMP, (int) biWidth, (int) biHeight); 360 break; 361 case 32: /* RGB image + Alpha channel */ 362 TRACEMS2(cinfo, 1, JTRC_BMP, (int) biWidth, (int) biHeight); 363 break; 364 default: 365 ERREXIT(cinfo, JERR_BMP_BADDEPTH); 366 break; 367 } 368 if (biCompression != 0) 369 ERREXIT(cinfo, JERR_BMP_COMPRESSED); 370 371 if (biXPelsPerMeter > 0 && biYPelsPerMeter > 0) { 372 /* Set JFIF density parameters from the BMP data */ 373 cinfo->X_density = (UINT16) (biXPelsPerMeter/100); /* 100 cm per meter */ 374 cinfo->Y_density = (UINT16) (biYPelsPerMeter/100); 375 cinfo->density_unit = 2; /* dots/cm */ 376 } 377 break; 378 default: 379 ERREXIT(cinfo, JERR_BMP_BADHEADER); 380 return; 381 } 382 383 if (biWidth <= 0 || biHeight <= 0) 384 ERREXIT(cinfo, JERR_BMP_EMPTY); 385 if (biPlanes != 1) 386 ERREXIT(cinfo, JERR_BMP_BADPLANES); 387 388 /* Compute distance to bitmap data --- will adjust for colormap below */ 389 bPad = bfOffBits - (headerSize + 14); 390 391 /* Read the colormap, if any */ 392 if (mapentrysize > 0) { 393 if (biClrUsed <= 0) 394 biClrUsed = 256; /* assume it's 256 */ 395 else if (biClrUsed > 256) 396 ERREXIT(cinfo, JERR_BMP_BADCMAP); 397 /* Allocate space to store the colormap */ 398 source->colormap = (*cinfo->mem->alloc_sarray) 399 ((j_common_ptr) cinfo, JPOOL_IMAGE, 400 (JDIMENSION) biClrUsed, (JDIMENSION) 3); 401 /* and read it from the file */ 402 read_colormap(source, (int) biClrUsed, mapentrysize); 403 /* account for size of colormap */ 404 bPad -= biClrUsed * mapentrysize; 405 } 406 407 /* Skip any remaining pad bytes */ 408 if (bPad < 0) /* incorrect bfOffBits value? */ 409 ERREXIT(cinfo, JERR_BMP_BADHEADER); 410 while (--bPad >= 0) { 411 (void) read_byte(source); 412 } 413 414 /* Compute row width in file, including padding to 4-byte boundary */ 415 if (source->bits_per_pixel == 24) 416 row_width = (JDIMENSION) (biWidth * 3); 417 else if (source->bits_per_pixel == 32) 418 row_width = (JDIMENSION) (biWidth * 4); 419 else 420 row_width = (JDIMENSION) biWidth; 421 while ((row_width & 3) != 0) row_width++; 422 source->row_width = row_width; 423 424 /* Allocate space for inversion array, prepare for preload pass */ 425 source->whole_image = (*cinfo->mem->request_virt_sarray) 426 ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, 427 row_width, (JDIMENSION) biHeight, (JDIMENSION) 1); 428 source->pub.get_pixel_rows = preload_image; 429 if (cinfo->progress != NULL) { 430 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; 431 progress->total_extra_passes++; /* count file input as separate pass */ 432 } 433 434 /* Allocate one-row buffer for returned data */ 435 source->pub.buffer = (*cinfo->mem->alloc_sarray) 436 ((j_common_ptr) cinfo, JPOOL_IMAGE, 437 (JDIMENSION) (biWidth * 3), (JDIMENSION) 1); 438 source->pub.buffer_height = 1; 439 440 cinfo->in_color_space = JCS_RGB; 441 cinfo->input_components = 3; 442 cinfo->data_precision = 8; 443 cinfo->image_width = (JDIMENSION) biWidth; 444 cinfo->image_height = (JDIMENSION) biHeight; 445} 446 447 448/* 449 * Finish up at the end of the file. 450 */ 451 452METHODDEF(void) 453finish_input_bmp (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) 454{ 455 /* no work */ 456} 457 458 459/* 460 * The module selection routine for BMP format input. 461 */ 462 463GLOBAL(cjpeg_source_ptr) 464jinit_read_bmp (j_compress_ptr cinfo) 465{ 466 bmp_source_ptr source; 467 468 /* Create module interface object */ 469 source = (bmp_source_ptr) 470 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 471 SIZEOF(bmp_source_struct)); 472 source->cinfo = cinfo; /* make back link for subroutines */ 473 /* Fill in method ptrs, except get_pixel_rows which start_input sets */ 474 source->pub.start_input = start_input_bmp; 475 source->pub.finish_input = finish_input_bmp; 476 477 return (cjpeg_source_ptr) source; 478} 479 480#endif /* BMP_SUPPORTED */ 481