1 /* 2 * wrbmp.c 3 * 4 * Copyright (C) 1994-1996, Thomas G. Lane. 5 * Modified 2017 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 write output images in Microsoft "BMP" 10 * format (MS Windows 3.x and OS/2 1.x flavors). 11 * Either 8-bit colormapped or 24-bit full-color format can be written. 12 * No compression is supported. 13 * 14 * These routines may need modification for non-Unix environments or 15 * specialized applications. As they stand, they assume output to 16 * an ordinary stdio stream. 17 * 18 * This code contributed by James Arthur Boucher. 19 */ 20 21 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */ 22 23 #ifdef BMP_SUPPORTED 24 25 26 /* 27 * To support 12-bit JPEG data, we'd have to scale output down to 8 bits. 28 * This is not yet implemented. 29 */ 30 31 #if BITS_IN_JSAMPLE != 8 32 Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */ 33 #endif 34 35 /* 36 * Since BMP stores scanlines bottom-to-top, we have to invert the image 37 * from JPEG's top-to-bottom order. To do this, we save the outgoing data 38 * in a virtual array during put_pixel_row calls, then actually emit the 39 * BMP file during finish_output. The virtual array contains one JSAMPLE per 40 * pixel if the output is grayscale or colormapped, three if it is full color. 41 */ 42 43 /* Private version of data destination object */ 44 45 typedef struct { 46 struct djpeg_dest_struct pub; /* public fields */ 47 48 boolean is_os2; /* saves the OS2 format request flag */ 49 50 jvirt_sarray_ptr whole_image; /* needed to reverse row order */ 51 JDIMENSION data_width; /* JSAMPLEs per row */ 52 JDIMENSION row_width; /* physical width of one row in the BMP file */ 53 int pad_bytes; /* number of padding bytes needed per row */ 54 JDIMENSION cur_output_row; /* next row# to write to virtual array */ 55 } bmp_dest_struct; 56 57 typedef bmp_dest_struct * bmp_dest_ptr; 58 59 60 /* Forward declarations */ 61 LOCAL(void) write_colormap 62 JPP((j_decompress_ptr cinfo, bmp_dest_ptr dest, 63 int map_colors, int map_entry_size)); 64 65 66 /* 67 * Write some pixel data. 68 * In this module rows_supplied will always be 1. 69 */ 70 71 METHODDEF(void) 72 put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, 73 JDIMENSION rows_supplied) 74 /* This version is for writing 24-bit pixels */ 75 { 76 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo; 77 JSAMPARRAY image_ptr; 78 register JSAMPROW inptr, outptr; 79 register JDIMENSION col; 80 int pad; 81 82 /* Access next row in virtual array */ 83 image_ptr = (*cinfo->mem->access_virt_sarray) 84 ((j_common_ptr) cinfo, dest->whole_image, 85 dest->cur_output_row, (JDIMENSION) 1, TRUE); 86 dest->cur_output_row++; 87 88 /* Transfer data. Note destination values must be in BGR order 89 * (even though Microsoft's own documents say the opposite). 90 */ 91 inptr = dest->pub.buffer[0]; 92 outptr = image_ptr[0]; 93 for (col = cinfo->output_width; col > 0; col--) { 94 outptr[2] = *inptr++; /* can omit GETJSAMPLE() safely */ 95 outptr[1] = *inptr++; 96 outptr[0] = *inptr++; 97 outptr += 3; 98 } 99 100 /* Zero out the pad bytes. */ 101 pad = dest->pad_bytes; 102 while (--pad >= 0) 103 *outptr++ = 0; 104 } 105 106 METHODDEF(void) 107 put_gray_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, 108 JDIMENSION rows_supplied) 109 /* This version is for grayscale OR quantized color output */ 110 { 111 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo; 112 JSAMPARRAY image_ptr; 113 register JSAMPROW inptr, outptr; 114 register JDIMENSION col; 115 int pad; 116 117 /* Access next row in virtual array */ 118 image_ptr = (*cinfo->mem->access_virt_sarray) 119 ((j_common_ptr) cinfo, dest->whole_image, 120 dest->cur_output_row, (JDIMENSION) 1, TRUE); 121 dest->cur_output_row++; 122 123 /* Transfer data. */ 124 inptr = dest->pub.buffer[0]; 125 outptr = image_ptr[0]; 126 for (col = cinfo->output_width; col > 0; col--) { 127 *outptr++ = *inptr++; /* can omit GETJSAMPLE() safely */ 128 } 129 130 /* Zero out the pad bytes. */ 131 pad = dest->pad_bytes; 132 while (--pad >= 0) 133 *outptr++ = 0; 134 } 135 136 137 /* 138 * Startup: normally writes the file header. 139 * In this module we may as well postpone everything until finish_output. 140 */ 141 142 METHODDEF(void) 143 start_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) 144 { 145 /* no work here */ 146 } 147 148 149 /* 150 * Finish up at the end of the file. 151 * 152 * Here is where we really output the BMP file. 153 * 154 * First, routines to write the Windows and OS/2 variants of the file header. 155 */ 156 157 LOCAL(void) 158 write_bmp_header (j_decompress_ptr cinfo, bmp_dest_ptr dest) 159 /* Write a Windows-style BMP file header, including colormap if needed */ 160 { 161 char bmpfileheader[14]; 162 char bmpinfoheader[40]; 163 #define PUT_2B(array,offset,value) \ 164 (array[offset] = (char) ((value) & 0xFF), \ 165 array[offset+1] = (char) (((value) >> 8) & 0xFF)) 166 #define PUT_4B(array,offset,value) \ 167 (array[offset] = (char) ((value) & 0xFF), \ 168 array[offset+1] = (char) (((value) >> 8) & 0xFF), \ 169 array[offset+2] = (char) (((value) >> 16) & 0xFF), \ 170 array[offset+3] = (char) (((value) >> 24) & 0xFF)) 171 INT32 headersize, bfSize; 172 int bits_per_pixel, cmap_entries; 173 174 /* Compute colormap size and total file size */ 175 if (cinfo->out_color_space == JCS_RGB) { 176 if (cinfo->quantize_colors) { 177 /* Colormapped RGB */ 178 bits_per_pixel = 8; 179 cmap_entries = 256; 180 } else { 181 /* Unquantized, full color RGB */ 182 bits_per_pixel = 24; 183 cmap_entries = 0; 184 } 185 } else { 186 /* Grayscale output. We need to fake a 256-entry colormap. */ 187 bits_per_pixel = 8; 188 cmap_entries = 256; 189 } 190 /* File size */ 191 headersize = 14 + 40 + cmap_entries * 4; /* Header and colormap */ 192 bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height; 193 194 /* Set unused fields of header to 0 */ 195 MEMZERO(bmpfileheader, SIZEOF(bmpfileheader)); 196 MEMZERO(bmpinfoheader, SIZEOF(bmpinfoheader)); 197 198 /* Fill the file header */ 199 bmpfileheader[0] = 0x42; /* first 2 bytes are ASCII 'B', 'M' */ 200 bmpfileheader[1] = 0x4D; 201 PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */ 202 /* we leave bfReserved1 & bfReserved2 = 0 */ 203 PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */ 204 205 /* Fill the info header (Microsoft calls this a BITMAPINFOHEADER) */ 206 PUT_2B(bmpinfoheader, 0, 40); /* biSize */ 207 PUT_4B(bmpinfoheader, 4, cinfo->output_width); /* biWidth */ 208 PUT_4B(bmpinfoheader, 8, cinfo->output_height); /* biHeight */ 209 PUT_2B(bmpinfoheader, 12, 1); /* biPlanes - must be 1 */ 210 PUT_2B(bmpinfoheader, 14, bits_per_pixel); /* biBitCount */ 211 /* we leave biCompression = 0, for none */ 212 /* we leave biSizeImage = 0; this is correct for uncompressed data */ 213 if (cinfo->density_unit == 2) { /* if have density in dots/cm, then */ 214 PUT_4B(bmpinfoheader, 24, (INT32) (cinfo->X_density*100)); /* XPels/M */ 215 PUT_4B(bmpinfoheader, 28, (INT32) (cinfo->Y_density*100)); /* XPels/M */ 216 } 217 PUT_2B(bmpinfoheader, 32, cmap_entries); /* biClrUsed */ 218 /* we leave biClrImportant = 0 */ 219 220 if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14) 221 ERREXIT(cinfo, JERR_FILE_WRITE); 222 if (JFWRITE(dest->pub.output_file, bmpinfoheader, 40) != (size_t) 40) 223 ERREXIT(cinfo, JERR_FILE_WRITE); 224 225 if (cmap_entries > 0) 226 write_colormap(cinfo, dest, cmap_entries, 4); 227 } 228 229 230 LOCAL(void) 231 write_os2_header (j_decompress_ptr cinfo, bmp_dest_ptr dest) 232 /* Write an OS2-style BMP file header, including colormap if needed */ 233 { 234 char bmpfileheader[14]; 235 char bmpcoreheader[12]; 236 INT32 headersize, bfSize; 237 int bits_per_pixel, cmap_entries; 238 239 /* Compute colormap size and total file size */ 240 if (cinfo->out_color_space == JCS_RGB) { 241 if (cinfo->quantize_colors) { 242 /* Colormapped RGB */ 243 bits_per_pixel = 8; 244 cmap_entries = 256; 245 } else { 246 /* Unquantized, full color RGB */ 247 bits_per_pixel = 24; 248 cmap_entries = 0; 249 } 250 } else { 251 /* Grayscale output. We need to fake a 256-entry colormap. */ 252 bits_per_pixel = 8; 253 cmap_entries = 256; 254 } 255 /* File size */ 256 headersize = 14 + 12 + cmap_entries * 3; /* Header and colormap */ 257 bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height; 258 259 /* Set unused fields of header to 0 */ 260 MEMZERO(bmpfileheader, SIZEOF(bmpfileheader)); 261 MEMZERO(bmpcoreheader, SIZEOF(bmpcoreheader)); 262 263 /* Fill the file header */ 264 bmpfileheader[0] = 0x42; /* first 2 bytes are ASCII 'B', 'M' */ 265 bmpfileheader[1] = 0x4D; 266 PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */ 267 /* we leave bfReserved1 & bfReserved2 = 0 */ 268 PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */ 269 270 /* Fill the info header (Microsoft calls this a BITMAPCOREHEADER) */ 271 PUT_2B(bmpcoreheader, 0, 12); /* bcSize */ 272 PUT_2B(bmpcoreheader, 4, cinfo->output_width); /* bcWidth */ 273 PUT_2B(bmpcoreheader, 6, cinfo->output_height); /* bcHeight */ 274 PUT_2B(bmpcoreheader, 8, 1); /* bcPlanes - must be 1 */ 275 PUT_2B(bmpcoreheader, 10, bits_per_pixel); /* bcBitCount */ 276 277 if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14) 278 ERREXIT(cinfo, JERR_FILE_WRITE); 279 if (JFWRITE(dest->pub.output_file, bmpcoreheader, 12) != (size_t) 12) 280 ERREXIT(cinfo, JERR_FILE_WRITE); 281 282 if (cmap_entries > 0) 283 write_colormap(cinfo, dest, cmap_entries, 3); 284 } 285 286 287 /* 288 * Write the colormap. 289 * Windows uses BGR0 map entries; OS/2 uses BGR entries. 290 */ 291 292 LOCAL(void) 293 write_colormap (j_decompress_ptr cinfo, bmp_dest_ptr dest, 294 int map_colors, int map_entry_size) 295 { 296 JSAMPARRAY colormap = cinfo->colormap; 297 int num_colors = cinfo->actual_number_of_colors; 298 FILE * outfile = dest->pub.output_file; 299 int i; 300 301 if (colormap != NULL) { 302 if (cinfo->out_color_components == 3) { 303 /* Normal case with RGB colormap */ 304 for (i = 0; i < num_colors; i++) { 305 putc(GETJSAMPLE(colormap[2][i]), outfile); 306 putc(GETJSAMPLE(colormap[1][i]), outfile); 307 putc(GETJSAMPLE(colormap[0][i]), outfile); 308 if (map_entry_size == 4) 309 putc(0, outfile); 310 } 311 } else { 312 /* Grayscale colormap (only happens with grayscale quantization) */ 313 for (i = 0; i < num_colors; i++) { 314 putc(GETJSAMPLE(colormap[0][i]), outfile); 315 putc(GETJSAMPLE(colormap[0][i]), outfile); 316 putc(GETJSAMPLE(colormap[0][i]), outfile); 317 if (map_entry_size == 4) 318 putc(0, outfile); 319 } 320 } 321 } else { 322 /* If no colormap, must be grayscale data. Generate a linear "map". */ 323 for (i = 0; i < 256; i++) { 324 putc(i, outfile); 325 putc(i, outfile); 326 putc(i, outfile); 327 if (map_entry_size == 4) 328 putc(0, outfile); 329 } 330 } 331 /* Pad colormap with zeros to ensure specified number of colormap entries */ 332 if (i > map_colors) 333 ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, i); 334 for (; i < map_colors; i++) { 335 putc(0, outfile); 336 putc(0, outfile); 337 putc(0, outfile); 338 if (map_entry_size == 4) 339 putc(0, outfile); 340 } 341 } 342 343 344 METHODDEF(void) 345 finish_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) 346 { 347 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo; 348 register FILE * outfile = dest->pub.output_file; 349 JSAMPARRAY image_ptr; 350 register JSAMPROW data_ptr; 351 JDIMENSION row; 352 register JDIMENSION col; 353 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; 354 355 /* Write the header and colormap */ 356 if (dest->is_os2) 357 write_os2_header(cinfo, dest); 358 else 359 write_bmp_header(cinfo, dest); 360 361 /* Write the file body from our virtual array */ 362 for (row = cinfo->output_height; row > 0; row--) { 363 if (progress != NULL) { 364 progress->pub.pass_counter = (long) (cinfo->output_height - row); 365 progress->pub.pass_limit = (long) cinfo->output_height; 366 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); 367 } 368 image_ptr = (*cinfo->mem->access_virt_sarray) 369 ((j_common_ptr) cinfo, dest->whole_image, row-1, (JDIMENSION) 1, FALSE); 370 data_ptr = image_ptr[0]; 371 for (col = dest->row_width; col > 0; col--) { 372 putc(GETJSAMPLE(*data_ptr), outfile); 373 data_ptr++; 374 } 375 } 376 if (progress != NULL) 377 progress->completed_extra_passes++; 378 379 /* Make sure we wrote the output file OK */ 380 JFFLUSH(outfile); 381 if (JFERROR(outfile)) 382 ERREXIT(cinfo, JERR_FILE_WRITE); 383 } 384 385 386 /* 387 * The module selection routine for BMP format output. 388 */ 389 390 GLOBAL(djpeg_dest_ptr) 391 jinit_write_bmp (j_decompress_ptr cinfo, boolean is_os2) 392 { 393 bmp_dest_ptr dest; 394 JDIMENSION row_width; 395 396 /* Create module interface object, fill in method pointers */ 397 dest = (bmp_dest_ptr) 398 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 399 SIZEOF(bmp_dest_struct)); 400 dest->pub.start_output = start_output_bmp; 401 dest->pub.finish_output = finish_output_bmp; 402 dest->is_os2 = is_os2; 403 404 if (cinfo->out_color_space == JCS_GRAYSCALE) { 405 dest->pub.put_pixel_rows = put_gray_rows; 406 } else if (cinfo->out_color_space == JCS_RGB) { 407 if (cinfo->quantize_colors) 408 dest->pub.put_pixel_rows = put_gray_rows; 409 else 410 dest->pub.put_pixel_rows = put_pixel_rows; 411 } else { 412 ERREXIT(cinfo, JERR_BMP_COLORSPACE); 413 } 414 415 /* Calculate output image dimensions so we can allocate space */ 416 jpeg_calc_output_dimensions(cinfo); 417 418 /* Determine width of rows in the BMP file (padded to 4-byte boundary). */ 419 row_width = cinfo->output_width * cinfo->output_components; 420 dest->data_width = row_width; 421 while ((row_width & 3) != 0) row_width++; 422 dest->row_width = row_width; 423 dest->pad_bytes = (int) (row_width - dest->data_width); 424 425 /* Allocate space for inversion array, prepare for write pass */ 426 dest->whole_image = (*cinfo->mem->request_virt_sarray) 427 ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, 428 row_width, cinfo->output_height, (JDIMENSION) 1); 429 dest->cur_output_row = 0; 430 if (cinfo->progress != NULL) { 431 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; 432 progress->total_extra_passes++; /* count file input as separate pass */ 433 } 434 435 /* Create decompressor output buffer. */ 436 dest->pub.buffer = (*cinfo->mem->alloc_sarray) 437 ((j_common_ptr) cinfo, JPOOL_IMAGE, row_width, (JDIMENSION) 1); 438 dest->pub.buffer_height = 1; 439 440 return &dest->pub; 441 } 442 443 #endif /* BMP_SUPPORTED */ 444