rosapps/lib/libjpeg/rdbmp.c

   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 */