d07c171f |
1 | /* |
2 | // source code for the BMGImage functions |
3 | // |
4 | // Copyright (C) 2001 Michael S. Heiman |
5 | // |
6 | // You may use the software for any purpose you see fit. You may modify |
7 | // it, incorporate it in a commercial application, use it for school, |
8 | // even turn it in as homework. You must keep the Copyright in the |
9 | // header and source files. This software is not in the "Public Domain". |
10 | // You may use this software at your own risk. I have made a reasonable |
11 | // effort to verify that this software works in the manner I expect it to; |
12 | // however,... |
13 | // |
14 | // THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS" AND |
15 | // WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, INCLUDING |
16 | // WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A |
17 | // PARTICULAR PURPOSE. IN NO EVENT SHALL MICHAEL S. HEIMAN BE LIABLE TO |
18 | // YOU OR ANYONE ELSE FOR ANY DIRECT, SPECIAL, INCIDENTAL, INDIRECT OR |
19 | // CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING |
20 | // WITHOUT LIMITATION, LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, |
21 | // OR THE CLAIMS OF THIRD PARTIES, WHETHER OR NOT MICHAEL S. HEIMAN HAS |
22 | // BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON |
23 | // ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE |
24 | // POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE. |
25 | */ |
26 | |
27 | #include <memory.h> |
28 | #include <setjmp.h> |
29 | #include <stdlib.h> |
30 | |
31 | #include "BMGUtils.h" |
32 | |
33 | /* initializes a BMGImage to default values */ |
34 | void InitBMGImage( struct BMGImageStruct *img ) |
35 | { |
36 | img->width = img->height = 0; |
37 | img->bits_per_pixel = 0; |
38 | img->palette_size = 0; |
39 | img->bytes_per_palette_entry = 0; |
40 | img->bits = NULL; |
41 | img->palette = NULL; |
42 | img->opt_for_bmp = 0; |
43 | img->scan_width = 0; |
44 | img->transparency_index = -1; |
45 | } |
46 | |
47 | /* frees memory allocated to a BMGImage */ |
48 | void FreeBMGImage( struct BMGImageStruct *img ) |
49 | { |
50 | if ( img->bits != NULL ) |
51 | { |
52 | free( img->bits ); |
53 | img->bits = NULL; |
54 | } |
55 | if ( img->palette != NULL ) |
56 | { |
57 | free( img->palette ); |
58 | img->palette = NULL; |
59 | } |
60 | img->bits_per_pixel = 0; |
61 | img->palette_size = 0; |
62 | img->bytes_per_palette_entry = 0; |
63 | img->width = img->height = 0; |
64 | img->opt_for_bmp = 0; |
65 | img->scan_width = 0; |
66 | img->transparency_index = -1; |
67 | } |
68 | |
69 | /* allocates memory for the bits & palette. Assigned values to scan_line |
70 | & bits_per_palette_entry as well. Assumes opt_for_bmp has been set before |
71 | this function is called. Assumes that all images with bits_per_pixel <= 8 |
72 | require a palette. |
73 | */ |
74 | BMGError AllocateBMGImage( struct BMGImageStruct *img ) |
75 | { |
76 | unsigned int mempal; |
77 | |
78 | SetLastBMGError( BMG_OK ); |
79 | |
80 | /* make sure that all REQUIRED parameters are valid */ |
81 | if ( img->width * img->height <= 0 ) |
82 | { |
83 | SetLastBMGError(errInvalidSize); |
84 | return errInvalidSize; |
85 | } |
86 | |
87 | switch( img->bits_per_pixel ) |
88 | { |
89 | case 1: |
90 | case 4: |
91 | case 8: |
92 | case 16: |
93 | case 24: |
94 | case 32: |
95 | break; |
96 | default: |
97 | SetLastBMGError( errInvalidPixelFormat ); |
98 | return errInvalidPixelFormat; |
99 | } |
100 | |
101 | /* delete old memory */ |
102 | if ( img->bits != NULL ) |
103 | { |
104 | free( img->bits ); |
105 | img->bits = NULL; |
106 | } |
107 | if ( img->palette != NULL ) |
108 | { |
109 | free( img->palette ); |
110 | img->palette = NULL; |
111 | } |
112 | |
113 | /* allocate memory for the palette */ |
114 | if ( img->bits_per_pixel <= 8 ) |
115 | { |
116 | if ( img->opt_for_bmp > 0 ) |
117 | img->bytes_per_palette_entry = 4U; |
118 | else |
119 | { |
120 | /* we only support 3-byte and 4-byte palettes */ |
121 | if ( img->bytes_per_palette_entry <= 3U ) |
122 | img->bytes_per_palette_entry = 3U; |
123 | else |
124 | img->bytes_per_palette_entry = 4U; |
125 | } |
126 | /* |
127 | use bits_per_pixel to determine palette_size if none was |
128 | specified |
129 | */ |
130 | if ( img->palette_size == 0 ) |
131 | img->palette_size = (unsigned short)(1 << img->bits_per_pixel); |
132 | |
133 | mempal = img->bytes_per_palette_entry * img->palette_size; |
134 | img->palette = (unsigned char *)calloc( mempal, sizeof(unsigned char) ); |
135 | if ( img->palette == NULL ) |
136 | { |
137 | SetLastBMGError(errMemoryAllocation); |
138 | return errMemoryAllocation; |
139 | } |
140 | } |
141 | else |
142 | { |
143 | img->bytes_per_palette_entry = 0; |
144 | img->palette_size = 0; |
145 | } |
146 | |
147 | /* |
148 | set the scan width. Bitmaps optimized for windows have scan widths that |
149 | are evenly divisible by 4. |
150 | */ |
151 | img->scan_width = ( img->bits_per_pixel * img->width + 7 ) / 8; |
152 | if ( img->opt_for_bmp && img->scan_width % 4 ) |
153 | img->scan_width += 4 - img->scan_width % 4; |
154 | |
155 | /* allocate memory for the bits */ |
156 | mempal = img->scan_width * img->height; |
157 | if ( mempal > 0 ) |
158 | { |
159 | img->bits = (unsigned char *)calloc( mempal, sizeof( unsigned char) ); |
160 | if ( img->bits == NULL ) |
161 | { |
162 | if ( img->palette != NULL ) |
163 | { |
164 | free( img->palette ); |
165 | img->palette = NULL; |
166 | } |
167 | SetLastBMGError(errMemoryAllocation); |
168 | return errMemoryAllocation; |
169 | } |
170 | } |
171 | else |
172 | { |
173 | SetLastBMGError(errInvalidSize); |
174 | return errInvalidSize; |
175 | } |
176 | |
177 | return BMG_OK; |
178 | } |
179 | |
180 | /******************************************************************************* |
181 | A utility function for compressing paletted images. Will automatically |
182 | convert 8-bit paletted images to 1-bit or 4-bit paletted images based |
183 | upon palette_size. Assumes that indices in img->bits are valid. That is, |
184 | 0 <= img->bits[i] <= 1 for all i if 1-bit compression is desired, and |
185 | 0 <= img->bits[i] <= 15 for all i if 4-bit compression is desired Returns |
186 | BMG_OK if successful, or an error code otherwise. |
187 | *******************************************************************************/ |
188 | BMGError CompressBMGImage( struct BMGImageStruct *img ) |
189 | { |
190 | unsigned char new_bits_per_pixel; |
191 | unsigned int new_scan_width; |
192 | unsigned char *new_bits = NULL; |
193 | unsigned int new_bit_size; |
194 | unsigned char *new_row, *old_row, *p, *q; |
195 | unsigned char *end; |
196 | unsigned short scale; |
197 | |
198 | SetLastBMGError( BMG_OK ); |
199 | |
200 | /* if we cannot compress it then do no harm and return "true" */ |
201 | if ( img->palette == NULL || |
202 | img->palette_size > 16 || |
203 | img->bits_per_pixel != 8 ) |
204 | { |
205 | return BMG_OK; |
206 | } |
207 | |
208 | /* calculate new dimensions */ |
209 | new_bits_per_pixel = img->palette_size <= 2 ? 1U : 4U; |
210 | new_scan_width = ( new_bits_per_pixel * img->width + 7 ) / 8; |
211 | if ( img->opt_for_bmp > 0 && new_scan_width % 4 ) |
212 | new_scan_width += 4 - new_scan_width % 4; |
213 | new_bit_size = new_scan_width * img->height; |
214 | |
215 | /* allocate & test memory */ |
216 | new_bits = (unsigned char *)calloc( new_bit_size, sizeof(unsigned char) ); |
217 | if ( new_bits == NULL ) |
218 | { |
219 | SetLastBMGError( errMemoryAllocation ); |
220 | return errMemoryAllocation; |
221 | } |
222 | |
223 | old_row = img->bits; |
224 | for ( new_row = new_bits; new_row < new_bits + new_bit_size; |
225 | new_row += new_scan_width, old_row += img->scan_width ) |
226 | { |
227 | scale = 8 / new_bits_per_pixel; |
228 | end = new_row + img->width / scale; |
229 | p = old_row; |
230 | if ( new_bits_per_pixel == 1 ) |
231 | { |
232 | for ( q = new_row; q < end; q++, p += scale ) |
233 | { |
234 | *q = (unsigned char)( (p[0] << 7) | (p[1] << 6) | |
235 | (p[2] << 5) | (p[3] << 4) | |
236 | (p[4] << 3) | (p[5] << 2) | |
237 | (p[6] << 1) | p[7] ); |
238 | } |
239 | scale = img->width % scale; |
240 | if ( scale-- > 0 ) |
241 | { |
242 | *q = (unsigned char)(p[0] << 7); |
243 | if ( scale-- ) |
244 | { |
245 | *q |= (unsigned char)(p[1] << 6); |
246 | if ( scale-- ) |
247 | { |
248 | *q |= (unsigned char)(p[2] << 5); |
249 | if ( scale-- ) |
250 | { |
251 | *q |= (unsigned char)(p[3] << 4); |
252 | if ( scale-- ) |
253 | { |
254 | *q |= (unsigned char)(p[4] << 3); |
255 | if ( scale-- ) |
256 | { |
257 | *q |= (unsigned char)(p[5] << 2); |
258 | if ( scale-- ) |
259 | *q |= (unsigned char)(p[6] << 1); |
260 | } |
261 | } |
262 | } |
263 | } |
264 | } |
265 | } |
266 | } |
267 | else /* new_bits_per_pixel == 4 */ |
268 | { |
269 | for ( q = new_row; q < end; q++, p += scale ) |
270 | { |
271 | *q = (unsigned char)( (p[0] << 4) | (p[1] & 0x0F) ); |
272 | } |
273 | if ( img->width % scale ) |
274 | *q = (unsigned char)(p[0] << 4); |
275 | } |
276 | } |
277 | |
278 | /* replace old values with new values */ |
279 | free( img->bits ); |
280 | img->bits = new_bits; |
281 | img->scan_width = new_scan_width; |
282 | img->bits_per_pixel = new_bits_per_pixel; |
283 | |
284 | return BMG_OK; |
285 | } |
286 | |
287 | /* this function simply frees memory that was allocated by any function |
288 | in the BMGLib. This was required because acces violations occurred |
289 | when I tried to delete memory created by CreateRGBAArray in the demo |
290 | applications */ |
291 | void FreeBMGMemory( unsigned char *mem ) |
292 | { |
293 | if ( mem != NULL ) |
294 | free( mem ); |
295 | } |
296 | |
297 | /* converts a BGR to a gray scale |
298 | // color[0] = blue, color[1] = green, color[2] = red */ |
299 | static unsigned char CreateGrayScale( unsigned char *color ) |
300 | { |
301 | return (unsigned char)( 0.299f * color[2] + 0.587f * color[1] |
302 | + 0.114f * color[0] + 0.5f ); |
303 | } |
304 | |
305 | /* |
306 | // converts a color image to a gray scale image. If img is a 16 or |
307 | // 24-BPP image then it is converted to a 256 color grayscale bitmap. |
308 | // If img is a 1, 4, or 8 BPP image, then it will have the same number |
309 | // of grayscales as it has palette entries. If it is a 32-BPP bitmap then |
310 | // it will remain a 32-BPP bitmap to preserve the alpha channel. |
311 | // |
312 | // This function returns BMG_OK if successfull, or an error state |
313 | // otherwise. |
314 | */ |
315 | BMGError ConvertToGrayScale( struct BMGImageStruct *img ) |
316 | { |
317 | unsigned char *p, *q, *r, *end, gray; |
318 | |
319 | SetLastBMGError( BMG_OK ); |
320 | |
321 | /* if this is a paletted image then we simply need to convert the |
322 | // palette entries */ |
323 | switch ( img->bits_per_pixel ) |
324 | { |
325 | default: |
326 | end = img->palette + img->palette_size * img->bytes_per_palette_entry; |
327 | for ( p = img->palette; p < end; p += img->bytes_per_palette_entry ) |
328 | { |
329 | gray = CreateGrayScale( p ); |
330 | memset( (void *)p, gray, 3 ); |
331 | } |
332 | break; |
333 | /* 16 BPP image are converted to 24 BPP images */ |
334 | case 16: |
335 | { |
336 | BMGError tmp = Convert16to24( img ); |
337 | if ( tmp != BMG_OK ) |
338 | { |
339 | SetLastBMGError( tmp ); |
340 | return tmp; |
341 | } |
342 | } |
343 | case 24: |
344 | { |
345 | unsigned char *new_bits; |
346 | unsigned char *s, *s_end; |
347 | unsigned short i; |
348 | |
349 | /* calculate the new scan width */ |
350 | unsigned int new_scan_width = img->width; |
351 | if ( new_scan_width % 4 && img->opt_for_bmp ) |
352 | new_scan_width += 4 - new_scan_width % 4; |
353 | |
354 | /* allocate memory for the new pixel values */ |
355 | new_bits = (unsigned char *)calloc( new_scan_width * img->height, |
356 | sizeof(unsigned char) ); |
357 | if ( new_bits == NULL ) |
358 | { |
359 | SetLastBMGError( errMemoryAllocation ); |
360 | return errMemoryAllocation; |
361 | } |
362 | |
363 | /* allocate memory for a 256 gray scale palette */ |
364 | img->bytes_per_palette_entry = img->opt_for_bmp == 1 ? 4 : 3; |
365 | img->palette_size = 256; |
366 | img->palette = |
367 | (unsigned char *)calloc(img->bytes_per_palette_entry * |
368 | img->palette_size, |
369 | sizeof(unsigned char) ); |
370 | if ( img->palette == NULL ) |
371 | { |
372 | free( new_bits ); |
373 | img->bytes_per_palette_entry = 0; |
374 | img->palette_size = 0; |
375 | SetLastBMGError( errMemoryAllocation ); |
376 | return errMemoryAllocation; |
377 | } |
378 | |
379 | /* assign values to the gray scale palette */ |
380 | for ( i = 0; i < 256; i++ ) |
381 | { |
382 | p = img->palette + i * img->bytes_per_palette_entry; |
383 | memset( (void *)p, i, 3 ); |
384 | if ( img->bytes_per_palette_entry == 4 ) |
385 | p[3] = 0; |
386 | } |
387 | |
388 | /* cycle through the pixels and convert them to gray scale values */ |
389 | q = new_bits; |
390 | end = img->bits + img->scan_width * img->height; |
391 | |
392 | for ( p = img->bits; p < end; p += img->scan_width, q += new_scan_width ) |
393 | { |
394 | s_end = p + 3 * img->width; |
395 | r = q; |
396 | for ( s = p; s < s_end; s += 3, r++ ) |
397 | *r = CreateGrayScale( s ); |
398 | } |
399 | |
400 | free( img->bits ); |
401 | img->bits = new_bits; |
402 | img->scan_width = new_scan_width; |
403 | img->bits_per_pixel = 8; |
404 | |
405 | break; |
406 | } |
407 | case 32: |
408 | end = img->bits + img->scan_width * img->height; |
409 | for ( p = img->bits; p < end; p += img->scan_width ) |
410 | { |
411 | r = p + img->scan_width; |
412 | for ( q = p; q < r; q += 4 ) |
413 | { |
414 | gray = CreateGrayScale( q ); |
415 | memset( (void *)q, gray, 3 ); |
416 | } |
417 | } |
418 | break; |
419 | } |
420 | |
421 | return BMG_OK; |
422 | } |
423 | |
424 | /* |
425 | // converts a color image to a pseudo-gray scale image. This is a implementation |
426 | // is based upon the code published by Rich Franzen |
427 | // <http://rocq.home.att.net/pseudoGrey.html>. I have "simplified" the 2 functions |
428 | // he published into a single function. This implementation creates 1786 gray |
429 | // scales from a 24-bit image. 16-BPP images are converted to 24-BPP images. 24 |
430 | // and 32-BPP images will keep the same bitdepth. Paletted images and 16-BPP images |
431 | // are not supported. |
432 | // |
433 | // This function returns BMK_OK if successfull, |
434 | // errInvalidPixelFormat otherwise |
435 | */ |
436 | BMGError ConvertToPseudoGrayScale( struct BMGImageStruct *img ) |
437 | { |
438 | unsigned char *p, *p_end; |
439 | unsigned char *q, *q_end; |
440 | unsigned char gray; |
441 | unsigned int bytes_per_pixel; |
442 | |
443 | SetLastBMGError( errMemoryAllocation ); |
444 | |
445 | if ( img->bits_per_pixel <= 16 ) |
446 | { |
447 | SetLastBMGError( errInvalidPixelFormat ); |
448 | return errInvalidPixelFormat; |
449 | } |
450 | |
451 | bytes_per_pixel = img->bits_per_pixel / 8; |
452 | p_end = img->bits + img->scan_width * img->height; |
453 | |
454 | for ( p = img->bits; p < p_end; p += img->scan_width ) |
455 | { |
456 | q_end = p + bytes_per_pixel * img->width; |
457 | for ( q = p; q < q_end; q += bytes_per_pixel ) |
458 | { |
459 | /* Rich's code has 1 function that converts an RGB triplet to a float |
460 | // bounded by 0 and 1. He has a second function that converts a |
461 | // float to a pseudo gray value. Pseudo gray values are RGB triplets |
462 | // whose red, green and blue values differ by no more than 1. I have |
463 | // combined these two functions into a single function that simply |
464 | // looks for pseudo gray RGB triplets. If an RGB triplet meets this |
465 | // criteria, I leave it unchanged; otherwise, I use the common intensity |
466 | // conversion to create a grayscale value */ |
467 | unsigned char cmin, cmax; |
468 | |
469 | cmin = q[0]; |
470 | if ( q[1] < cmin ) |
471 | cmin = q[1]; |
472 | if ( q[2] < cmin ) |
473 | cmin = q[2]; |
474 | |
475 | cmax = q[0]; |
476 | if ( q[1] > cmax ) |
477 | cmax = q[1]; |
478 | if ( q[2] > cmax ) |
479 | cmax = q[2]; |
480 | |
481 | if ( cmax - cmin > 2 ) |
482 | { |
483 | gray = CreateGrayScale( q ); |
484 | memset( (void *)q, gray, 3 ); |
485 | } |
486 | } |
487 | } |
488 | |
489 | return BMG_OK; |
490 | } |
491 | |
492 | #ifdef _WIN32 |
493 | /******************************************************************************* |
494 | // extracts the dimensional information, pixel array, and color table from an |
495 | // HBITMAP. |
496 | // hBitmap can be a handle to a DIB or a DDB. This function assumes that DDBs |
497 | // will not have a palette. If you create a DDB on a 256-color graphics card, |
498 | // then the DDB will have a palette and this function will fail. |
499 | // |
500 | // returns BMK_OK if successfull, and error state otherwise. |
501 | ********************************************************************************/ |
502 | BMGError GetDataFromBitmap( HBITMAP hBitmap, |
503 | struct BMGImageStruct *img, |
504 | int remove_alpha ) |
505 | { |
506 | unsigned int DIBScanWidth; |
507 | DIBSECTION DS; |
508 | HWND hWnd = GetForegroundWindow(); |
509 | HDC hDC = NULL; |
510 | HDC hMemDC = NULL; |
511 | unsigned char red, green, blue; |
512 | int FreelpBits = 0; |
513 | unsigned int numBytes; |
514 | size_t soDIBSECTION = sizeof(DIBSECTION); |
515 | size_t soBITMAP = sizeof(BITMAP); |
516 | |
517 | unsigned char *p, *q, *lpBits, alpha; |
518 | |
519 | jmp_buf err_jmp; |
520 | int error; |
521 | BMGError bmgerr; |
522 | |
523 | /* error handler */ |
524 | error = setjmp( err_jmp ); |
525 | if ( error != 0 ) |
526 | { |
527 | if ( hMemDC != NULL ) |
528 | DeleteDC( hMemDC ); |
529 | if ( hDC != NULL ) |
530 | ReleaseDC( hWnd, hDC ); |
531 | if ( FreelpBits ) |
532 | free( lpBits ); |
533 | FreeBMGImage( img ); |
534 | SetLastBMGError( (BMGError)error ); |
535 | return (BMGError)error; |
536 | } |
537 | |
538 | SetLastBMGError( BMG_OK ); |
539 | /* check for valid bitmap*/ |
540 | if ( !hBitmap ) |
541 | longjmp( err_jmp, (int)errInvalidBitmapHandle ); |
542 | |
543 | /* Extract DIBSECTION info from the HBITMAP. numBytes will equal |
544 | // soDIBSECTION (84) if hBitmap is a handle to a DIBSECTION (DIB). |
545 | // numBytes will equal soBITMAP (24) if hBitmap is a handle to a |
546 | // BITMAP (DDB). */ |
547 | numBytes = GetObject( hBitmap, sizeof(DIBSECTION), &DS ); |
548 | if ( numBytes == 0 ) |
549 | longjmp( err_jmp, (int)errWindowsAPI ); |
550 | |
551 | img->opt_for_bmp = 1; |
552 | if ( numBytes == soDIBSECTION ) |
553 | { |
554 | img->width = DS.dsBmih.biWidth; |
555 | img->height = DS.dsBmih.biHeight; |
556 | img->bits_per_pixel = (unsigned char)DS.dsBmih.biBitCount; |
557 | if ( img->bits_per_pixel <= 8 && DS.dsBmih.biClrUsed > 0 ) |
558 | img->palette_size = (unsigned short)DS.dsBmih.biClrUsed; |
559 | lpBits = (unsigned char *)DS.dsBm.bmBits; |
560 | } |
561 | /* this may be a DDB which must be handled differently */ |
562 | else if ( numBytes == soBITMAP ) |
563 | { |
564 | BITMAP bm; |
565 | BITMAPINFO bmi; |
566 | |
567 | if ( GetObject( hBitmap, sizeof(BITMAP), &bm ) == 0 ) |
568 | longjmp( err_jmp, (int)errWindowsAPI ); |
569 | |
570 | /* DDB with a palette */ |
571 | if ( bm.bmBitsPixel <= 8 ) |
572 | longjmp( err_jmp, (int)errInvalidPixelFormat ); |
573 | |
574 | img->width = bm.bmWidth; |
575 | img->height = bm.bmHeight; |
576 | img->bits_per_pixel = (unsigned char)bm.bmBitsPixel; |
577 | bmi = InternalCreateBMI( bm.bmWidth, bm.bmHeight, bm.bmBitsPixel, |
578 | BI_RGB ); |
579 | |
580 | lpBits = (unsigned char *)calloc( bm.bmHeight * bm.bmWidthBytes, |
581 | sizeof(unsigned char) ); |
582 | if ( lpBits == 0 ) |
583 | longjmp( err_jmp, (int)errMemoryAllocation ); |
584 | FreelpBits = 1; |
585 | hDC = GetDC( hWnd ); |
586 | if ( GetDIBits(hDC, hBitmap, 0, bm.bmHeight, (void *)lpBits, &bmi, |
587 | DIB_RGB_COLORS ) == 0 ) |
588 | longjmp( err_jmp, (int)errWindowsAPI ); |
589 | ReleaseDC( hWnd, hDC ); |
590 | hDC = NULL; |
591 | } |
592 | else /* I have no idea what this is */ |
593 | longjmp( err_jmp, (int)errInvalidBitmapHandle ); |
594 | |
595 | /* allocate memory */ |
596 | bmgerr = AllocateBMGImage( img ); |
597 | if ( bmgerr != BMG_OK ) |
598 | longjmp( err_jmp, (int)bmgerr ); |
599 | |
600 | /* dimensions */ |
601 | DIBScanWidth = ( img->width * img->bits_per_pixel + 7 )/8; |
602 | if ( DIBScanWidth % 4 ) |
603 | DIBScanWidth += 4 - DIBScanWidth % 4; |
604 | |
605 | p = img->bits; |
606 | for ( q = lpBits; q < lpBits + DIBScanWidth * img->height; |
607 | p += img->scan_width, q += DIBScanWidth ) |
608 | { |
609 | memcpy( (void *)p, (void *)q, DIBScanWidth ); |
610 | } |
611 | |
612 | /* "un-blend" the image if requested. NOTE: unblending only works with |
613 | // bland backgrounds */ |
614 | if ( remove_alpha > 0 && |
615 | img->bits_per_pixel == 32 && |
616 | numBytes == soDIBSECTION ) |
617 | { |
618 | unsigned char *color = GetBackgroundColor(); |
619 | red = color[2]; |
620 | green = color[1]; |
621 | blue = color[0]; |
622 | |
623 | for ( p = img->bits; p < img->bits + img->scan_width * img->height; |
624 | p += 4 ) |
625 | { |
626 | alpha = p[3]; |
627 | p[2] = InverseAlphaComp( p[2], alpha, blue); |
628 | p[1] = InverseAlphaComp( p[1], alpha, green); |
629 | p[0] = InverseAlphaComp( p[0], alpha, red); |
630 | } |
631 | } |
632 | |
633 | /* 32-bit DDBs must have the alpha channel set to 0xFF before they are |
634 | // saved to a file. This may not be true for all devices that generate |
635 | // 32-bit DDBs. I have only created 32-bit DDBs using an Intense3D Wildcat |
636 | // 4110 card. The alpha channel was always 0. */ |
637 | if (img->bits_per_pixel == 32 && numBytes == soBITMAP ) |
638 | { |
639 | for ( p = img->bits + 3; p < img->bits + img->scan_width * img->height; |
640 | p += 4 ) |
641 | { |
642 | *p = 0xFF; |
643 | } |
644 | } |
645 | |
646 | /* create palette if necessary */ |
647 | if ( img->bits_per_pixel <= 8 ) |
648 | { |
649 | hDC = GetDC( hWnd ); |
650 | hMemDC = CreateCompatibleDC( hDC ); |
651 | SelectObject( hMemDC, hBitmap ); |
652 | if ( !GetDIBColorTable( hMemDC, 0, img->palette_size, |
653 | (RGBQUAD *)img->palette ) ) |
654 | { |
655 | longjmp( err_jmp, (int)errWindowsAPI ); |
656 | } |
657 | DeleteDC( hMemDC ); |
658 | ReleaseDC( hWnd, hDC ); |
659 | } |
660 | |
661 | if ( FreelpBits ) |
662 | free( lpBits ); |
663 | |
664 | return BMG_OK; |
665 | } |
666 | |
667 | /******************************************************************************* |
668 | // this function creates a bitmap from raw data. Returns an HBITMAP if it |
669 | // succeeds, otherwise NULL */ |
670 | HBITMAP CreateBitmapFromData( struct BMGImageStruct img, |
671 | int alpha_blend ) |
672 | { |
673 | HBITMAP hBitmap = NULL; |
674 | HDC hMemDC = NULL; |
675 | HWND hWnd = GetForegroundWindow(); |
676 | HDC hDC = NULL; |
677 | RGBQUAD *pColor = NULL; |
678 | BITMAPINFO bmi; |
679 | unsigned char *rbits; |
680 | unsigned char *bits; |
681 | unsigned char *lpBits; |
682 | unsigned char alpha; |
683 | unsigned int DIBScanWidth; |
684 | int i; |
685 | |
686 | jmp_buf err_jmp; |
687 | int error; |
688 | |
689 | /* error handler */ |
690 | error = setjmp( err_jmp ); |
691 | if ( error != 0 ) |
692 | { |
693 | if ( hMemDC != NULL ) |
694 | DeleteDC( hMemDC ); |
695 | if ( hDC != NULL ) |
696 | ReleaseDC( hWnd, hDC ); |
697 | if ( pColor != NULL && img.bytes_per_palette_entry == 3U ) |
698 | free( pColor ); |
699 | SetLastBMGError( (BMGError)error ); |
700 | return 0; |
701 | } |
702 | |
703 | SetLastBMGError( BMG_OK ); |
704 | |
705 | /* create the DIB section that will hold this bitmap */ |
706 | bmi = InternalCreateBMI( (unsigned int)img.width, (unsigned int)img.height, |
707 | (unsigned short)img.bits_per_pixel, BI_RGB ); |
708 | bmi.bmiHeader.biClrUsed = bmi.bmiHeader.biClrImportant = |
709 | img.palette_size; |
710 | hDC = GetDC( hWnd ); |
711 | hBitmap = CreateDIBSection( hDC, &bmi, DIB_RGB_COLORS, |
712 | (void **)&lpBits, NULL, 0 ); |
713 | |
714 | if ( !hBitmap || !lpBits ) |
715 | longjmp( err_jmp, (int)errWindowsAPI ); |
716 | |
717 | /* create a palette if needed */ |
718 | if ( img.palette != NULL ) |
719 | { |
720 | /* copy pixel data to pColor */ |
721 | if ( img.bytes_per_palette_entry == 4U ) |
722 | pColor = (RGBQUAD *)img.palette; |
723 | else /* bytes_per_palette_entry === 3 */ |
724 | { |
725 | pColor = (RGBQUAD *)calloc(img.palette_size, sizeof(RGBQUAD) ); |
726 | if ( pColor == NULL ) |
727 | longjmp( err_jmp, (int)errMemoryAllocation ); |
728 | |
729 | bits = img.palette; |
730 | for ( i = 0; i < (int)bmi.bmiHeader.biClrUsed; i++, bits += 3 ) |
731 | { |
732 | pColor[i].rgbRed = bits[0]; |
733 | pColor[i].rgbGreen = bits[1]; |
734 | pColor[i].rgbBlue = bits[2]; |
735 | } |
736 | } |
737 | |
738 | if ( img.transparency_index > -1 ) |
739 | { |
740 | unsigned char *color = GetBackgroundColor(); |
741 | rbits = img.palette + img.bytes_per_palette_entry * |
742 | img.transparency_index; |
743 | rbits[0] = color[2]; |
744 | rbits[1] = color[1]; |
745 | rbits[2] = color[0]; |
746 | } |
747 | /* save color table in bitmap */ |
748 | hMemDC = CreateCompatibleDC( hDC ); |
749 | SelectObject( hMemDC, hBitmap ); |
750 | if ( !SetDIBColorTable( hMemDC, 0, img.palette_size, pColor ) ) |
751 | longjmp( err_jmp, (int)errWindowsAPI ); |
752 | |
753 | DeleteDC( hMemDC ); |
754 | hMemDC = NULL; |
755 | if ( img.bytes_per_palette_entry == 3U ) |
756 | free( pColor ); |
757 | pColor = NULL; |
758 | } |
759 | |
760 | /* calculate the scan line width */ |
761 | DIBScanWidth = img.scan_width; |
762 | if ( DIBScanWidth % 4 ) |
763 | DIBScanWidth += 4 - DIBScanWidth % 4; |
764 | |
765 | if ( img.opt_for_bmp == 0 ) |
766 | { |
767 | /* store bits into hBitmap */ |
768 | rbits = img.bits; |
769 | for ( bits = lpBits; |
770 | bits < lpBits + img.height * DIBScanWidth; |
771 | bits += DIBScanWidth, rbits += img.scan_width ) |
772 | { |
773 | memcpy( (void *)bits, (void *)rbits, img.scan_width ); |
774 | } |
775 | } |
776 | else |
777 | memcpy( (void *)lpBits, (void *)img.bits, img.scan_width * img.height ); |
778 | |
779 | /* blend the image with the window background if alpha pixels |
780 | // are present */ |
781 | if ( img.bits_per_pixel == 32 ) |
782 | { |
783 | /* blend with a bland background */ |
784 | if ( alpha_blend == 1 ) |
785 | { |
786 | unsigned char *color = GetBackgroundColor(); |
787 | unsigned char red = color[2]; |
788 | unsigned char green = color[1]; |
789 | unsigned char blue = color[0]; |
790 | |
791 | for ( rbits = lpBits; |
792 | rbits < lpBits + img.height*DIBScanWidth; |
793 | rbits += DIBScanWidth ) |
794 | { |
795 | for ( bits = rbits; bits < rbits + DIBScanWidth; bits += 4 ) |
796 | { |
797 | alpha = bits[3]; |
798 | bits[2] = AlphaComp( bits[2], alpha, blue ); |
799 | bits[1] = AlphaComp( bits[1], alpha, green ); |
800 | bits[0] = AlphaComp( bits[0], alpha, red ); |
801 | } |
802 | } |
803 | } |
804 | /* blend with a background image */ |
805 | else if ( alpha_blend == 2 ) |
806 | { |
807 | unsigned char *bg_bits; |
808 | unsigned char *bg_bits_2; |
809 | unsigned int bg_bytes_per_pixel; |
810 | struct BMGImageStruct *bg = GetBackgroundImage(); |
811 | |
812 | /* make sure we can blend with a background image |
813 | // I assume that the background image is invalid if it does not |
814 | // have a valid width */ |
815 | if ( bg->width <= 0 || bg->height <= 0 ) |
816 | longjmp( err_jmp, (int)errUndefinedBGImage ); |
817 | |
818 | /* I cannot blend a foreground image with a background image that |
819 | // is smaller than it */ |
820 | if ( bg->width < img.width || bg->height < img.height ) |
821 | longjmp( err_jmp, (int)errBGImageTooSmall ); |
822 | |
823 | /* the background image was forced to be a 24 or 32-BPP image; |
824 | // therefore, we can safely divide by 8 to determined the |
825 | // bytes per pixel*/ |
826 | bg_bytes_per_pixel = bg->bits_per_pixel / 8; |
827 | |
828 | /* I will assume that the upper left corner of the input image |
829 | // must be aligned with the upper left corner of the background |
830 | // image. This allows me to have background images that are bigger |
831 | // than the input image. */ |
832 | bg_bits = bg->bits; |
833 | for ( rbits = lpBits; |
834 | rbits < lpBits + img.height*DIBScanWidth; |
835 | rbits += DIBScanWidth, bg_bits += bg->scan_width ) |
836 | { |
837 | bg_bits_2 = bg_bits; |
838 | for ( bits = rbits; bits < rbits + DIBScanWidth; |
839 | bits += 4, bg_bits_2 += bg_bytes_per_pixel ) |
840 | { |
841 | alpha = bits[3]; |
842 | bits[2] = AlphaComp( bits[2], alpha, bg_bits_2[2] ); |
843 | bits[1] = AlphaComp( bits[1], alpha, bg_bits_2[1] ); |
844 | bits[0] = AlphaComp( bits[0], alpha, bg_bits_2[0] ); |
845 | } |
846 | } |
847 | |
848 | } |
849 | } |
850 | |
851 | ReleaseDC( hWnd, hDC ); |
852 | |
853 | return hBitmap; |
854 | } |
855 | #endif // _WIN32 |
856 | /****************************************************************************** |
857 | // ConvertPaletteToRGB converts paletted and 16-BPP images that do not have |
858 | // transparent pixels to 24-BPP images. Paletted images with transparent pixels |
859 | // are converted to 32-BPP images. 24-BPP and 32-BPP images are simply copied |
860 | // to the output structure |
861 | // |
862 | // INPUTS: |
863 | // img_in |
864 | // OUTPUTS: |
865 | // img_out |
866 | // |
867 | // returns BMG_OK if no errors occur, an error code otherwise |
868 | ******************************************************************************/ |
869 | BMGError ConvertPaletteToRGB( struct BMGImageStruct img_in, |
870 | struct BMGImageStruct *img_out ) |
871 | { |
872 | jmp_buf err_jmp; |
873 | int error; |
874 | |
875 | /* error handler */ |
876 | error = setjmp( err_jmp ); |
877 | if ( error != 0 ) |
878 | { |
879 | FreeBMGImage( img_out ); |
880 | SetLastBMGError( (BMGError)error ); |
881 | return (BMGError)error; |
882 | } |
883 | |
884 | SetLastBMGError( BMG_OK ); |
885 | |
886 | if ( img_in.height == 0 || img_in.width == 0 ) |
887 | longjmp( err_jmp, (int)errInvalidSize ); |
888 | |
889 | InitBMGImage( img_out ); |
890 | |
891 | // copy 16, 24, and 32-BPP images into the output image |
892 | if ( img_in.bits_per_pixel > 8 ) |
893 | { |
894 | BMGError out; |
895 | img_out->bits_per_pixel = img_in.bits_per_pixel; |
896 | out = CopyBMGImage( img_in, img_out ); |
897 | if ( out != BMG_OK ) |
898 | longjmp( err_jmp, (int)out ); |
899 | |
900 | // 16-BPP are converted to 24-BPP images |
901 | if ( img_out->bits_per_pixel == 16 ) |
902 | { |
903 | out = Convert16to24( img_out ); |
904 | if ( out != BMG_OK ) |
905 | longjmp( err_jmp, (int)out ); |
906 | } |
907 | } |
908 | else // convert paletted images to 24-BPP BGR or 32-BPP BGRA images |
909 | { |
910 | BMGError out; |
911 | unsigned char *buf; |
912 | unsigned int scan_width; |
913 | int dealloc; |
914 | unsigned char *q0, *q1, *p0, *p1; |
915 | unsigned int bpp; |
916 | |
917 | // allocate memory for the 24-BPP output image |
918 | img_out->width = img_in.width; |
919 | img_out->height = img_in.height; |
920 | img_out->opt_for_bmp = img_in.opt_for_bmp; |
921 | img_out->bits_per_pixel = img_in.transparency_index > -1 ? 32 : 24; |
922 | |
923 | out = AllocateBMGImage( img_out ); |
924 | if ( out != BMG_OK ) |
925 | longjmp( err_jmp, (int)out ); |
926 | |
927 | // 1-BPP and 4-BPP images are packed, so we need to unpack them |
928 | if ( img_in.bits_per_pixel < 8 ) |
929 | { |
930 | dealloc = 1; |
931 | scan_width = img_in.width; |
932 | buf = (unsigned char *)malloc(scan_width * img_in.height); |
933 | if ( buf == NULL ) |
934 | longjmp( err_jmp, (int)errMemoryAllocation ); |
935 | |
936 | if ( img_in.bits_per_pixel == 1 ) |
937 | Convert1to8( img_in, buf ); |
938 | else |
939 | Convert4to8( img_in, buf ); |
940 | } |
941 | else // simply point to the bits array if we have a 8-BPP image |
942 | { |
943 | dealloc = 0; |
944 | buf = img_in.bits; |
945 | scan_width = img_in.scan_width; |
946 | } |
947 | |
948 | // convert palette indices to BGR pixels |
949 | bpp = img_out->bits_per_pixel / 8; |
950 | q0 = img_out->bits; |
951 | for ( p0 = buf; p0 < buf + scan_width * img_in.height; |
952 | p0 += scan_width, q0 += img_out->scan_width ) |
953 | { |
954 | q1 = q0; |
955 | for ( p1 = p0; p1 < p0 + img_in.width; p1++, q1 += bpp ) |
956 | { |
957 | memcpy( (void *)q1, |
958 | (void *)(img_in.palette + *p1 * img_in.bytes_per_palette_entry), 3 ); |
959 | if ( bpp == 4 ) |
960 | { |
961 | q1[3] = *p1 == img_in.transparency_index ? 0 : 0xFF; |
962 | } |
963 | } |
964 | } |
965 | |
966 | if ( dealloc == 1 ) |
967 | free( buf ); |
968 | } |
969 | |
970 | return BMG_OK; |
971 | } |
972 | |
973 | /****************************************************************************** |
974 | // CopyBMG copies the contents of img_in into img_out. |
975 | // |
976 | // CopyBMG returns BMG_OK if successful, otherwise, it returns an error code |
977 | ******************************************************************************/ |
978 | BMGError CopyBMGImage( struct BMGImageStruct img_in, |
979 | struct BMGImageStruct *img_out ) |
980 | { |
981 | BMGError out = BMG_OK; |
982 | SetLastBMGError( out ); |
983 | |
984 | FreeBMGImage( img_out ); |
985 | |
986 | img_out->height = img_in.height; |
987 | img_out->width = img_in.width; |
988 | img_out->bits_per_pixel = img_in.bits_per_pixel; |
989 | img_out->palette_size = img_in.palette_size; |
990 | img_out->opt_for_bmp = img_in.opt_for_bmp; |
991 | |
992 | if ( img_in.width > 0 && img_in.height > 0 ) |
993 | { |
994 | out = AllocateBMGImage( img_out ); |
995 | if ( out == BMG_OK ) |
996 | { |
997 | memcpy( (void *)img_out->bits, (void *)img_in.bits, |
998 | img_in.scan_width * img_in.height ); |
999 | if ( img_in.palette_size > 0 ) |
1000 | memcpy( (void *)img_out->palette, (void *)img_in.palette, |
1001 | img_in.palette_size * img_in.bytes_per_palette_entry ); |
1002 | } |
1003 | } |
1004 | |
1005 | return out; |
1006 | } |
1007 | |
1008 | /* sets the background color for alpha blending |
1009 | color points to an array of 4 unsigned chars |
1010 | color[0] = blue, color[1] = green, color[2] = red, color[3] = unused */ |
1011 | void SetBMGBackgroundColor( unsigned char *color ) |
1012 | { |
1013 | memcpy( (void *)GetBackgroundColor(), (void *)color, |
1014 | 4*sizeof(unsigned char) ); |
1015 | } |
1016 | |
1017 | #ifdef _WIN32 |
1018 | /* defines the background bitmap that is used for alpha blending & transparent |
1019 | pixels */ |
1020 | BMGError SetBMGBackgroundBitmap( HBITMAP hBitmap ) |
1021 | { |
1022 | BMGError out; |
1023 | struct BMGImageStruct tmp; |
1024 | InitBMGImage( &tmp ); |
1025 | |
1026 | /* first we extract the data from the HBITMAP */ |
1027 | out = GetDataFromBitmap( hBitmap, &tmp, 0 ); |
1028 | if ( out == BMG_OK ) |
1029 | { |
1030 | /* clean up the old background image */ |
1031 | FreeBMGImage( GetBackgroundImage() ); |
1032 | |
1033 | /* next, we convert paletted & 16-BPP images to 24 or 32-BPP images. |
1034 | // this will simplify the alpha blending. */ |
1035 | out = ConvertPaletteToRGB( tmp, GetBackgroundImage() ); |
1036 | } |
1037 | |
1038 | return out; |
1039 | } |
1040 | #endif // _WIN32 |
1041 | |
1042 | /* defines the background image that is used for alpha blending & transparent |
1043 | pixels */ |
1044 | BMGError SetBMGBackgroundImage( struct BMGImageStruct img ) |
1045 | { |
1046 | /* clean up the old background image */ |
1047 | FreeBMGImage( GetBackgroundImage() ); |
1048 | |
1049 | /* convert paletted and 16-BPP images to 24-BPP or 32-BPP images. This |
1050 | // will simplify the alpha blending logic*/ |
1051 | return ConvertPaletteToRGB( img, GetBackgroundImage() ); |
1052 | } |
1053 | |