source: trunk/libjpeg/rdbmp.c @ 15

Last change on this file since 15 was 15, checked in by Eugene Romanenko, 15 years ago

needed libs update

File size: 13.9 KB
Line 
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
32typedef unsigned char U_CHAR;
33#define UCH(x)  ((int) (x))
34#else /* !HAVE_UNSIGNED_CHAR */
35#ifdef CHAR_IS_UNSIGNED
36typedef char U_CHAR;
37#define UCH(x)  ((int) (x))
38#else
39typedef 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
50typedef struct _bmp_source_struct * bmp_source_ptr;
51
52typedef 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
67LOCAL(int)
68read_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
80LOCAL(void)
81read_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
118METHODDEF(JDIMENSION)
119get_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
149METHODDEF(JDIMENSION)
150get_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
186METHODDEF(JDIMENSION)
187preload_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
240METHODDEF(void)
241start_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
411METHODDEF(void)
412finish_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
422GLOBAL(cjpeg_source_ptr)
423jinit_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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