workbench/libs/jpeg/wrbmp.c

   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 */