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