1 /* 2 * wrbmp.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 write output images in Microsoft "BMP" 9 * format (MS Windows 3.x and OS/2 1.x flavors). 10 * Either 8-bit colormapped or 24-bit full-color format can be written. 11 * No compression is supported. 12 * 13 * These routines may need modification for non-Unix environments or 14 * specialized applications. As they stand, they assume output to 15 * an ordinary stdio stream. 16 * 17 * This code contributed by James Arthur Boucher. 18 */ 19 20 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */ 21 22 #ifdef BMP_SUPPORTED 23 24 25 /* 26 * To support 12-bit JPEG data, we'd have to scale output down to 8 bits. 27 * This is not yet implemented. 28 */ 29 30 #if BITS_IN_JSAMPLE != 8 31 Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */ 32 #endif 33 34 /* 35 * Since BMP stores scanlines bottom-to-top, we have to invert the image 36 * from JPEG's top-to-bottom order. To do this, we save the outgoing data 37 * in a virtual array during put_pixel_row calls, then actually emit the 38 * BMP file during finish_output. The virtual array contains one JSAMPLE per 39 * pixel if the output is grayscale or colormapped, three if it is full color. 40 */ 41 42 /* Private version of data destination object */ 43 44 typedef struct { 45 struct djpeg_dest_struct pub; /* public fields */ 46 47 boolean is_os2; /* saves the OS2 format request flag */ 48 49 jvirt_sarray_ptr whole_image; /* needed to reverse row order */ 50 JDIMENSION data_width; /* JSAMPLEs per row */ 51 JDIMENSION row_width; /* physical width of one row in the BMP file */ 52 int pad_bytes; /* number of padding bytes needed per row */ 53 JDIMENSION cur_output_row; /* next row# to write to virtual array */ 54 } bmp_dest_struct; 55 56 typedef bmp_dest_struct * bmp_dest_ptr; 57 58 59 /* Forward declarations */ 60 LOCAL(void) write_colormap 61 JPP((j_decompress_ptr cinfo, bmp_dest_ptr dest, 62 int map_colors, int map_entry_size)); 63 64 65 /* 66 * Write some pixel data. 67 * In this module rows_supplied will always be 1. 68 */ 69 70 METHODDEF(void) 71 put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, 72 JDIMENSION rows_supplied) 73 /* This version is for writing 24-bit pixels */ 74 { 75 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo; 76 JSAMPARRAY image_ptr; 77 register JSAMPROW inptr, outptr; 78 register JDIMENSION col; 79 int pad; 80 81 /* Access next row in virtual array */ 82 image_ptr = (*cinfo->mem->access_virt_sarray) 83 ((j_common_ptr) cinfo, dest->whole_image, 84 dest->cur_output_row, (JDIMENSION) 1, TRUE); 85 dest->cur_output_row++; 86 87 /* Transfer data. Note destination values must be in BGR order 88 * (even though Microsoft's own documents say the opposite). 89 */ 90 inptr = dest->pub.buffer[0]; 91 outptr = image_ptr[0]; 92 for (col = cinfo->output_width; col > 0; col--) { 93 outptr[2] = *inptr++; /* can omit GETJSAMPLE() safely */ 94 outptr[1] = *inptr++; 95 outptr[0] = *inptr++; 96 outptr += 3; 97 } 98 99 /* Zero out the pad bytes. */ 100 pad = dest->pad_bytes; 101 while (--pad >= 0) 102 *outptr++ = 0; 103 } 104 105 METHODDEF(void) 106 put_gray_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, 107 JDIMENSION rows_supplied) 108 /* This version is for grayscale OR quantized color output */ 109 { 110 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo; 111 JSAMPARRAY image_ptr; 112 register JSAMPROW inptr, outptr; 113 register JDIMENSION col; 114 int pad; 115 116 /* Access next row in virtual array */ 117 image_ptr = (*cinfo->mem->access_virt_sarray) 118 ((j_common_ptr) cinfo, dest->whole_image, 119 dest->cur_output_row, (JDIMENSION) 1, TRUE); 120 dest->cur_output_row++; 121 122 /* Transfer data. */ 123 inptr = dest->pub.buffer[0]; 124 outptr = image_ptr[0]; 125 for (col = cinfo->output_width; col > 0; col--) { 126 *outptr++ = *inptr++; /* can omit GETJSAMPLE() safely */ 127 } 128 129 /* Zero out the pad bytes. */ 130 pad = dest->pad_bytes; 131 while (--pad >= 0) 132 *outptr++ = 0; 133 } 134 135 136 /* 137 * Startup: normally writes the file header. 138 * In this module we may as well postpone everything until finish_output. 139 */ 140 141 METHODDEF(void) 142 start_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) 143 { 144 /* no work here */ 145 } 146 147 148 /* 149 * Finish up at the end of the file. 150 * 151 * Here is where we really output the BMP file. 152 * 153 * First, routines to write the Windows and OS/2 variants of the file header. 154 */ 155 156 LOCAL(void) 157 write_bmp_header (j_decompress_ptr cinfo, bmp_dest_ptr dest) 158 /* Write a Windows-style BMP file header, including colormap if needed */ 159 { 160 char bmpfileheader[14]; 161 char bmpinfoheader[40]; 162 #define PUT_2B(array,offset,value) \ 163 (array[offset] = (char) ((value) & 0xFF), \ 164 array[offset+1] = (char) (((value) >> 8) & 0xFF)) 165 #define PUT_4B(array,offset,value) \ 166 (array[offset] = (char) ((value) & 0xFF), \ 167 array[offset+1] = (char) (((value) >> 8) & 0xFF), \ 168 array[offset+2] = (char) (((value) >> 16) & 0xFF), \ 169 array[offset+3] = (char) (((value) >> 24) & 0xFF)) 170 INT32 headersize, bfSize; 171 int bits_per_pixel, cmap_entries; 172 173 /* Compute colormap size and total file size */ 174 if (cinfo->out_color_space == JCS_RGB) { 175 if (cinfo->quantize_colors) { 176 /* Colormapped RGB */ 177 bits_per_pixel = 8; 178 cmap_entries = 256; 179 } else { 180 /* Unquantized, full color RGB */ 181 bits_per_pixel = 24; 182 cmap_entries = 0; 183 } 184 } else { 185 /* Grayscale output. We need to fake a 256-entry colormap. */ 186 bits_per_pixel = 8; 187 cmap_entries = 256; 188 } 189 /* File size */ 190 headersize = 14 + 40 + cmap_entries * 4; /* Header and colormap */ 191 bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height; 192 193 /* Set unused fields of header to 0 */ 194 MEMZERO(bmpfileheader, SIZEOF(bmpfileheader)); 195 MEMZERO(bmpinfoheader, SIZEOF(bmpinfoheader)); 196 197 /* Fill the file header */ 198 bmpfileheader[0] = 0x42; /* first 2 bytes are ASCII 'B', 'M' */ 199 bmpfileheader[1] = 0x4D; 200 PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */ 201 /* we leave bfReserved1 & bfReserved2 = 0 */ 202 PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */ 203 204 /* Fill the info header (Microsoft calls this a BITMAPINFOHEADER) */ 205 PUT_2B(bmpinfoheader, 0, 40); /* biSize */ 206 PUT_4B(bmpinfoheader, 4, cinfo->output_width); /* biWidth */ 207 PUT_4B(bmpinfoheader, 8, cinfo->output_height); /* biHeight */ 208 PUT_2B(bmpinfoheader, 12, 1); /* biPlanes - must be 1 */ 209 PUT_2B(bmpinfoheader, 14, bits_per_pixel); /* biBitCount */ 210 /* we leave biCompression = 0, for none */ 211 /* we leave biSizeImage = 0; this is correct for uncompressed data */ 212 if (cinfo->density_unit == 2) { /* if have density in dots/cm, then */ 213 PUT_4B(bmpinfoheader, 24, (INT32) (cinfo->X_density*100)); /* XPels/M */ 214 PUT_4B(bmpinfoheader, 28, (INT32) (cinfo->Y_density*100)); /* XPels/M */ 215 } 216 PUT_2B(bmpinfoheader, 32, cmap_entries); /* biClrUsed */ 217 /* we leave biClrImportant = 0 */ 218 219 if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14) 220 ERREXIT(cinfo, JERR_FILE_WRITE); 221 if (JFWRITE(dest->pub.output_file, bmpinfoheader, 40) != (size_t) 40) 222 ERREXIT(cinfo, JERR_FILE_WRITE); 223 224 if (cmap_entries > 0) 225 write_colormap(cinfo, dest, cmap_entries, 4); 226 } 227 228 229 LOCAL(void) 230 write_os2_header (j_decompress_ptr cinfo, bmp_dest_ptr dest) 231 /* Write an OS2-style BMP file header, including colormap if needed */ 232 { 233 char bmpfileheader[14]; 234 char bmpcoreheader[12]; 235 INT32 headersize, bfSize; 236 int bits_per_pixel, cmap_entries; 237 238 /* Compute colormap size and total file size */ 239 if (cinfo->out_color_space == JCS_RGB) { 240 if (cinfo->quantize_colors) { 241 /* Colormapped RGB */ 242 bits_per_pixel = 8; 243 cmap_entries = 256; 244 } else { 245 /* Unquantized, full color RGB */ 246 bits_per_pixel = 24; 247 cmap_entries = 0; 248 } 249 } else { 250 /* Grayscale output. We need to fake a 256-entry colormap. */ 251 bits_per_pixel = 8; 252 cmap_entries = 256; 253 } 254 /* File size */ 255 headersize = 14 + 12 + cmap_entries * 3; /* Header and colormap */ 256 bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height; 257 258 /* Set unused fields of header to 0 */ 259 MEMZERO(bmpfileheader, SIZEOF(bmpfileheader)); 260 MEMZERO(bmpcoreheader, SIZEOF(bmpcoreheader)); 261 262 /* Fill the file header */ 263 bmpfileheader[0] = 0x42; /* first 2 bytes are ASCII 'B', 'M' */ 264 bmpfileheader[1] = 0x4D; 265 PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */ 266 /* we leave bfReserved1 & bfReserved2 = 0 */ 267 PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */ 268 269 /* Fill the info header (Microsoft calls this a BITMAPCOREHEADER) */ 270 PUT_2B(bmpcoreheader, 0, 12); /* bcSize */ 271 PUT_2B(bmpcoreheader, 4, cinfo->output_width); /* bcWidth */ 272 PUT_2B(bmpcoreheader, 6, cinfo->output_height); /* bcHeight */ 273 PUT_2B(bmpcoreheader, 8, 1); /* bcPlanes - must be 1 */ 274 PUT_2B(bmpcoreheader, 10, bits_per_pixel); /* bcBitCount */ 275 276 if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14) 277 ERREXIT(cinfo, JERR_FILE_WRITE); 278 if (JFWRITE(dest->pub.output_file, bmpcoreheader, 12) != (size_t) 12) 279 ERREXIT(cinfo, JERR_FILE_WRITE); 280 281 if (cmap_entries > 0) 282 write_colormap(cinfo, dest, cmap_entries, 3); 283 } 284 285 286 /* 287 * Write the colormap. 288 * Windows uses BGR0 map entries; OS/2 uses BGR entries. 289 */ 290 291 LOCAL(void) 292 write_colormap (j_decompress_ptr cinfo, bmp_dest_ptr dest, 293 int map_colors, int map_entry_size) 294 { 295 JSAMPARRAY colormap = cinfo->colormap; 296 int num_colors = cinfo->actual_number_of_colors; 297 FILE * outfile = dest->pub.output_file; 298 int i; 299 300 if (colormap != NULL) { 301 if (cinfo->out_color_components == 3) { 302 /* Normal case with RGB colormap */ 303 for (i = 0; i < num_colors; i++) { 304 putc(GETJSAMPLE(colormap[2][i]), outfile); 305 putc(GETJSAMPLE(colormap[1][i]), outfile); 306 putc(GETJSAMPLE(colormap[0][i]), outfile); 307 if (map_entry_size == 4) 308 putc(0, outfile); 309 } 310 } else { 311 /* Grayscale colormap (only happens with grayscale quantization) */ 312 for (i = 0; i < num_colors; i++) { 313 putc(GETJSAMPLE(colormap[0][i]), outfile); 314 putc(GETJSAMPLE(colormap[0][i]), outfile); 315 putc(GETJSAMPLE(colormap[0][i]), outfile); 316 if (map_entry_size == 4) 317 putc(0, outfile); 318 } 319 } 320 } else { 321 /* If no colormap, must be grayscale data. Generate a linear "map". */ 322 for (i = 0; i < 256; i++) { 323 putc(i, outfile); 324 putc(i, outfile); 325 putc(i, outfile); 326 if (map_entry_size == 4) 327 putc(0, outfile); 328 } 329 } 330 /* Pad colormap with zeros to ensure specified number of colormap entries */ 331 if (i > map_colors) 332 ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, i); 333 for (; i < map_colors; i++) { 334 putc(0, outfile); 335 putc(0, outfile); 336 putc(0, outfile); 337 if (map_entry_size == 4) 338 putc(0, outfile); 339 } 340 } 341 342 343 METHODDEF(void) 344 finish_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) 345 { 346 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo; 347 register FILE * outfile = dest->pub.output_file; 348 JSAMPARRAY image_ptr; 349 register JSAMPROW data_ptr; 350 JDIMENSION row; 351 register JDIMENSION col; 352 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; 353 354 /* Write the header and colormap */ 355 if (dest->is_os2) 356 write_os2_header(cinfo, dest); 357 else 358 write_bmp_header(cinfo, dest); 359 360 /* Write the file body from our virtual array */ 361 for (row = cinfo->output_height; row > 0; row--) { 362 if (progress != NULL) { 363 progress->pub.pass_counter = (long) (cinfo->output_height - row); 364 progress->pub.pass_limit = (long) cinfo->output_height; 365 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); 366 } 367 image_ptr = (*cinfo->mem->access_virt_sarray) 368 ((j_common_ptr) cinfo, dest->whole_image, row-1, (JDIMENSION) 1, FALSE); 369 data_ptr = image_ptr[0]; 370 for (col = dest->row_width; col > 0; col--) { 371 putc(GETJSAMPLE(*data_ptr), outfile); 372 data_ptr++; 373 } 374 } 375 if (progress != NULL) 376 progress->completed_extra_passes++; 377 378 /* Make sure we wrote the output file OK */ 379 fflush(outfile); 380 if (ferror(outfile)) 381 ERREXIT(cinfo, JERR_FILE_WRITE); 382 } 383 384 385 /* 386 * The module selection routine for BMP format output. 387 */ 388 389 GLOBAL(djpeg_dest_ptr) 390 jinit_write_bmp (j_decompress_ptr cinfo, boolean is_os2) 391 { 392 bmp_dest_ptr dest; 393 JDIMENSION row_width; 394 395 /* Create module interface object, fill in method pointers */ 396 dest = (bmp_dest_ptr) 397 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 398 SIZEOF(bmp_dest_struct)); 399 dest->pub.start_output = start_output_bmp; 400 dest->pub.finish_output = finish_output_bmp; 401 dest->is_os2 = is_os2; 402 403 if (cinfo->out_color_space == JCS_GRAYSCALE) { 404 dest->pub.put_pixel_rows = put_gray_rows; 405 } else if (cinfo->out_color_space == JCS_RGB) { 406 if (cinfo->quantize_colors) 407 dest->pub.put_pixel_rows = put_gray_rows; 408 else 409 dest->pub.put_pixel_rows = put_pixel_rows; 410 } else { 411 ERREXIT(cinfo, JERR_BMP_COLORSPACE); 412 } 413 414 /* Calculate output image dimensions so we can allocate space */ 415 jpeg_calc_output_dimensions(cinfo); 416 417 /* Determine width of rows in the BMP file (padded to 4-byte boundary). */ 418 row_width = cinfo->output_width * cinfo->output_components; 419 dest->data_width = row_width; 420 while ((row_width & 3) != 0) row_width++; 421 dest->row_width = row_width; 422 dest->pad_bytes = (int) (row_width - dest->data_width); 423 424 /* Allocate space for inversion array, prepare for write pass */ 425 dest->whole_image = (*cinfo->mem->request_virt_sarray) 426 ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, 427 row_width, cinfo->output_height, (JDIMENSION) 1); 428 dest->cur_output_row = 0; 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 /* Create decompressor output buffer. */ 435 dest->pub.buffer = (*cinfo->mem->alloc_sarray) 436 ((j_common_ptr) cinfo, JPOOL_IMAGE, row_width, (JDIMENSION) 1); 437 dest->pub.buffer_height = 1; 438 439 return (djpeg_dest_ptr) dest; 440 } 441 442 #endif /* BMP_SUPPORTED */ 443
