1 /*
2 * wrbmp.c
3 *
4 * Copyright (C) 1994-1996, Thomas G. Lane.
5 * Modified 2017-2019 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)
put_pixel_rows(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo,JDIMENSION rows_supplied)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 register JSAMPROW inptr, outptr;
78 register JDIMENSION col;
79 int pad;
80
81 /* Access next row in virtual array */
82 outptr = * (*cinfo->mem->access_virt_sarray) ((j_common_ptr) cinfo,
83 dest->whole_image, dest->cur_output_row, (JDIMENSION) 1, TRUE);
84 dest->cur_output_row++;
85
86 /* Transfer data. Note destination values must be in BGR order
87 * (even though Microsoft's own documents say the opposite).
88 */
89 inptr = dest->pub.buffer[0];
90 for (col = cinfo->output_width; col > 0; col--) {
91 outptr[2] = *inptr++; /* can omit GETJSAMPLE() safely */
92 outptr[1] = *inptr++;
93 outptr[0] = *inptr++;
94 outptr += 3;
95 }
96
97 /* Zero out the pad bytes. */
98 pad = dest->pad_bytes;
99 while (--pad >= 0)
100 *outptr++ = 0;
101 }
102
103 METHODDEF(void)
put_gray_rows(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo,JDIMENSION rows_supplied)104 put_gray_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
105 JDIMENSION rows_supplied)
106 /* This version is for grayscale OR quantized color output */
107 {
108 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo;
109 register JSAMPROW inptr, outptr;
110 register JDIMENSION col;
111 int pad;
112
113 /* Access next row in virtual array */
114 outptr = * (*cinfo->mem->access_virt_sarray) ((j_common_ptr) cinfo,
115 dest->whole_image, dest->cur_output_row, (JDIMENSION) 1, TRUE);
116 dest->cur_output_row++;
117
118 /* Transfer data. */
119 inptr = dest->pub.buffer[0];
120 for (col = cinfo->output_width; col > 0; col--) {
121 *outptr++ = *inptr++; /* can omit GETJSAMPLE() safely */
122 }
123
124 /* Zero out the pad bytes. */
125 pad = dest->pad_bytes;
126 while (--pad >= 0)
127 *outptr++ = 0;
128 }
129
130
131 /*
132 * Startup: normally writes the file header.
133 * In this module we may as well postpone everything until finish_output.
134 */
135
136 METHODDEF(void)
start_output_bmp(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo)137 start_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
138 {
139 /* no work here */
140 }
141
142
143 /*
144 * Finish up at the end of the file.
145 *
146 * Here is where we really output the BMP file.
147 *
148 * First, routines to write the Windows and OS/2 variants of the file header.
149 */
150
151 LOCAL(void)
write_bmp_header(j_decompress_ptr cinfo,bmp_dest_ptr dest)152 write_bmp_header (j_decompress_ptr cinfo, bmp_dest_ptr dest)
153 /* Write a Windows-style BMP file header, including colormap if needed */
154 {
155 char bmpfileheader[14];
156 char bmpinfoheader[40];
157 #define PUT_2B(array, offset, value) \
158 (array[offset] = (char) ((value) & 0xFF), \
159 array[offset+1] = (char) (((value) >> 8) & 0xFF))
160 #define PUT_4B(array, offset, value) \
161 (array[offset] = (char) ((value) & 0xFF), \
162 array[offset+1] = (char) (((value) >> 8) & 0xFF), \
163 array[offset+2] = (char) (((value) >> 16) & 0xFF), \
164 array[offset+3] = (char) (((value) >> 24) & 0xFF))
165 INT32 headersize, bfSize;
166 int bits_per_pixel, cmap_entries;
167
168 /* Compute colormap size and total file size */
169 if (cinfo->out_color_space == JCS_RGB) {
170 if (cinfo->quantize_colors) {
171 /* Colormapped RGB */
172 bits_per_pixel = 8;
173 cmap_entries = 256;
174 } else {
175 /* Unquantized, full color RGB */
176 bits_per_pixel = 24;
177 cmap_entries = 0;
178 }
179 } else {
180 /* Grayscale output. We need to fake a 256-entry colormap. */
181 bits_per_pixel = 8;
182 cmap_entries = 256;
183 }
184 /* File size */
185 headersize = 14 + 40 + cmap_entries * 4; /* Header and colormap */
186 bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height;
187
188 /* Set unused fields of header to 0 */
189 MEMZERO(bmpfileheader, SIZEOF(bmpfileheader));
190 MEMZERO(bmpinfoheader, SIZEOF(bmpinfoheader));
191
192 /* Fill the file header */
193 bmpfileheader[0] = 0x42; /* first 2 bytes are ASCII 'B', 'M' */
194 bmpfileheader[1] = 0x4D;
195 PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */
196 /* we leave bfReserved1 & bfReserved2 = 0 */
197 PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */
198
199 /* Fill the info header (Microsoft calls this a BITMAPINFOHEADER) */
200 PUT_2B(bmpinfoheader, 0, 40); /* biSize */
201 PUT_4B(bmpinfoheader, 4, cinfo->output_width); /* biWidth */
202 PUT_4B(bmpinfoheader, 8, cinfo->output_height); /* biHeight */
203 PUT_2B(bmpinfoheader, 12, 1); /* biPlanes - must be 1 */
204 PUT_2B(bmpinfoheader, 14, bits_per_pixel); /* biBitCount */
205 /* we leave biCompression = 0, for none */
206 /* we leave biSizeImage = 0; this is correct for uncompressed data */
207 if (cinfo->density_unit == 2) { /* if have density in dots/cm, then */
208 PUT_4B(bmpinfoheader, 24, (INT32) (cinfo->X_density*100)); /* XPels/M */
209 PUT_4B(bmpinfoheader, 28, (INT32) (cinfo->Y_density*100)); /* XPels/M */
210 }
211 PUT_2B(bmpinfoheader, 32, cmap_entries); /* biClrUsed */
212 /* we leave biClrImportant = 0 */
213
214 if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14)
215 ERREXIT(cinfo, JERR_FILE_WRITE);
216 if (JFWRITE(dest->pub.output_file, bmpinfoheader, 40) != (size_t) 40)
217 ERREXIT(cinfo, JERR_FILE_WRITE);
218
219 if (cmap_entries > 0)
220 write_colormap(cinfo, dest, cmap_entries, 4);
221 }
222
223
224 LOCAL(void)
write_os2_header(j_decompress_ptr cinfo,bmp_dest_ptr dest)225 write_os2_header (j_decompress_ptr cinfo, bmp_dest_ptr dest)
226 /* Write an OS2-style BMP file header, including colormap if needed */
227 {
228 char bmpfileheader[14];
229 char bmpcoreheader[12];
230 INT32 headersize, bfSize;
231 int bits_per_pixel, cmap_entries;
232
233 /* Compute colormap size and total file size */
234 if (cinfo->out_color_space == JCS_RGB) {
235 if (cinfo->quantize_colors) {
236 /* Colormapped RGB */
237 bits_per_pixel = 8;
238 cmap_entries = 256;
239 } else {
240 /* Unquantized, full color RGB */
241 bits_per_pixel = 24;
242 cmap_entries = 0;
243 }
244 } else {
245 /* Grayscale output. We need to fake a 256-entry colormap. */
246 bits_per_pixel = 8;
247 cmap_entries = 256;
248 }
249 /* File size */
250 headersize = 14 + 12 + cmap_entries * 3; /* Header and colormap */
251 bfSize = headersize + (INT32) dest->row_width * (INT32) cinfo->output_height;
252
253 /* Set unused fields of header to 0 */
254 MEMZERO(bmpfileheader, SIZEOF(bmpfileheader));
255 MEMZERO(bmpcoreheader, SIZEOF(bmpcoreheader));
256
257 /* Fill the file header */
258 bmpfileheader[0] = 0x42; /* first 2 bytes are ASCII 'B', 'M' */
259 bmpfileheader[1] = 0x4D;
260 PUT_4B(bmpfileheader, 2, bfSize); /* bfSize */
261 /* we leave bfReserved1 & bfReserved2 = 0 */
262 PUT_4B(bmpfileheader, 10, headersize); /* bfOffBits */
263
264 /* Fill the info header (Microsoft calls this a BITMAPCOREHEADER) */
265 PUT_2B(bmpcoreheader, 0, 12); /* bcSize */
266 PUT_2B(bmpcoreheader, 4, cinfo->output_width); /* bcWidth */
267 PUT_2B(bmpcoreheader, 6, cinfo->output_height); /* bcHeight */
268 PUT_2B(bmpcoreheader, 8, 1); /* bcPlanes - must be 1 */
269 PUT_2B(bmpcoreheader, 10, bits_per_pixel); /* bcBitCount */
270
271 if (JFWRITE(dest->pub.output_file, bmpfileheader, 14) != (size_t) 14)
272 ERREXIT(cinfo, JERR_FILE_WRITE);
273 if (JFWRITE(dest->pub.output_file, bmpcoreheader, 12) != (size_t) 12)
274 ERREXIT(cinfo, JERR_FILE_WRITE);
275
276 if (cmap_entries > 0)
277 write_colormap(cinfo, dest, cmap_entries, 3);
278 }
279
280
281 /*
282 * Write the colormap.
283 * Windows uses BGR0 map entries; OS/2 uses BGR entries.
284 */
285
286 LOCAL(void)
write_colormap(j_decompress_ptr cinfo,bmp_dest_ptr dest,int map_colors,int map_entry_size)287 write_colormap (j_decompress_ptr cinfo, bmp_dest_ptr dest,
288 int map_colors, int map_entry_size)
289 {
290 JSAMPARRAY colormap = cinfo->colormap;
291 int num_colors = cinfo->actual_number_of_colors;
292 FILE * outfile = dest->pub.output_file;
293 int i;
294
295 if (colormap != NULL) {
296 if (cinfo->out_color_components == 3) {
297 /* Normal case with RGB colormap */
298 for (i = 0; i < num_colors; i++) {
299 putc(GETJSAMPLE(colormap[2][i]), outfile);
300 putc(GETJSAMPLE(colormap[1][i]), outfile);
301 putc(GETJSAMPLE(colormap[0][i]), outfile);
302 if (map_entry_size == 4)
303 putc(0, outfile);
304 }
305 } else {
306 /* Grayscale colormap (only happens with grayscale quantization) */
307 for (i = 0; i < num_colors; i++) {
308 putc(GETJSAMPLE(colormap[0][i]), outfile);
309 putc(GETJSAMPLE(colormap[0][i]), outfile);
310 putc(GETJSAMPLE(colormap[0][i]), outfile);
311 if (map_entry_size == 4)
312 putc(0, outfile);
313 }
314 }
315 } else {
316 /* If no colormap, must be grayscale data. Generate a linear "map". */
317 for (i = 0; i < 256; i++) {
318 putc(i, outfile);
319 putc(i, outfile);
320 putc(i, outfile);
321 if (map_entry_size == 4)
322 putc(0, outfile);
323 }
324 }
325 /* Pad colormap to ensure specified number of colormap entries */
326 if (i > map_colors)
327 ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, i);
328 for (; i < map_colors; i++) {
329 putc(CENTERJSAMPLE, outfile);
330 putc(CENTERJSAMPLE, outfile);
331 putc(CENTERJSAMPLE, outfile);
332 if (map_entry_size == 4)
333 putc(0, outfile);
334 }
335 }
336
337
338 METHODDEF(void)
finish_output_bmp(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo)339 finish_output_bmp (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
340 {
341 bmp_dest_ptr dest = (bmp_dest_ptr) dinfo;
342 register FILE * outfile = dest->pub.output_file;
343 register JSAMPROW data_ptr;
344 JDIMENSION row;
345 register JDIMENSION col;
346 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
347
348 /* Write the header and colormap */
349 if (dest->is_os2)
350 write_os2_header(cinfo, dest);
351 else
352 write_bmp_header(cinfo, dest);
353
354 /* Write the file body from our virtual array */
355 for (row = cinfo->output_height; row > 0; row--) {
356 if (progress != NULL) {
357 progress->pub.pass_counter = (long) (cinfo->output_height - row);
358 progress->pub.pass_limit = (long) cinfo->output_height;
359 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
360 }
361 data_ptr = * (*cinfo->mem->access_virt_sarray) ((j_common_ptr) cinfo,
362 dest->whole_image, row - 1, (JDIMENSION) 1, FALSE);
363 for (col = dest->row_width; col > 0; col--) {
364 putc(GETJSAMPLE(*data_ptr), outfile);
365 data_ptr++;
366 }
367 }
368 if (progress != NULL)
369 progress->completed_extra_passes++;
370
371 /* Make sure we wrote the output file OK */
372 JFFLUSH(outfile);
373 if (JFERROR(outfile))
374 ERREXIT(cinfo, JERR_FILE_WRITE);
375 }
376
377
378 /*
379 * The module selection routine for BMP format output.
380 */
381
382 GLOBAL(djpeg_dest_ptr)
jinit_write_bmp(j_decompress_ptr cinfo,boolean is_os2)383 jinit_write_bmp (j_decompress_ptr cinfo, boolean is_os2)
384 {
385 bmp_dest_ptr dest;
386 JDIMENSION row_width;
387
388 /* Create module interface object, fill in method pointers */
389 dest = (bmp_dest_ptr) (*cinfo->mem->alloc_small)
390 ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(bmp_dest_struct));
391 dest->pub.start_output = start_output_bmp;
392 dest->pub.finish_output = finish_output_bmp;
393 dest->is_os2 = is_os2;
394
395 switch (cinfo->out_color_space) {
396 case JCS_GRAYSCALE:
397 dest->pub.put_pixel_rows = put_gray_rows;
398 break;
399 case JCS_RGB:
400 if (cinfo->quantize_colors)
401 dest->pub.put_pixel_rows = put_gray_rows;
402 else
403 dest->pub.put_pixel_rows = put_pixel_rows;
404 break;
405 default:
406 ERREXIT(cinfo, JERR_BMP_COLORSPACE);
407 }
408
409 /* Calculate output image dimensions so we can allocate space */
410 jpeg_calc_output_dimensions(cinfo);
411
412 /* Determine width of rows in the BMP file (padded to 4-byte boundary). */
413 row_width = cinfo->output_width * cinfo->output_components;
414 dest->data_width = row_width;
415 while ((row_width & 3) != 0) row_width++;
416 dest->row_width = row_width;
417 dest->pad_bytes = (int) (row_width - dest->data_width);
418
419 /* Allocate space for inversion array, prepare for write pass */
420 dest->whole_image = (*cinfo->mem->request_virt_sarray)
421 ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
422 row_width, cinfo->output_height, (JDIMENSION) 1);
423 dest->cur_output_row = 0;
424 if (cinfo->progress != NULL) {
425 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
426 progress->total_extra_passes++; /* count file input as separate pass */
427 }
428
429 /* Create decompressor output buffer. */
430 dest->pub.buffer = (*cinfo->mem->alloc_sarray)
431 ((j_common_ptr) cinfo, JPOOL_IMAGE, row_width, (JDIMENSION) 1);
432 dest->pub.buffer_height = 1;
433
434 return &dest->pub;
435 }
436
437 #endif /* BMP_SUPPORTED */
438