diff options
Diffstat (limited to 'libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwtran.c')
-rw-r--r-- | libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwtran.c | 633 |
1 files changed, 0 insertions, 633 deletions
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwtran.c b/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwtran.c deleted file mode 100644 index 96608ef..0000000 --- a/libraries/irrlicht-1.8/source/Irrlicht/libpng/pngwtran.c +++ /dev/null | |||
@@ -1,633 +0,0 @@ | |||
1 | |||
2 | /* pngwtran.c - transforms the data in a row for PNG writers | ||
3 | * | ||
4 | * Last changed in libpng 1.5.6 [November 3, 2011] | ||
5 | * Copyright (c) 1998-2011 Glenn Randers-Pehrson | ||
6 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) | ||
7 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) | ||
8 | * | ||
9 | * This code is released under the libpng license. | ||
10 | * For conditions of distribution and use, see the disclaimer | ||
11 | * and license in png.h | ||
12 | */ | ||
13 | |||
14 | #include "pngpriv.h" | ||
15 | |||
16 | #ifdef PNG_WRITE_SUPPORTED | ||
17 | |||
18 | #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED | ||
19 | /* Transform the data according to the user's wishes. The order of | ||
20 | * transformations is significant. | ||
21 | */ | ||
22 | void /* PRIVATE */ | ||
23 | png_do_write_transformations(png_structp png_ptr, png_row_infop row_info) | ||
24 | { | ||
25 | png_debug(1, "in png_do_write_transformations"); | ||
26 | |||
27 | if (png_ptr == NULL) | ||
28 | return; | ||
29 | |||
30 | #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED | ||
31 | if (png_ptr->transformations & PNG_USER_TRANSFORM) | ||
32 | if (png_ptr->write_user_transform_fn != NULL) | ||
33 | (*(png_ptr->write_user_transform_fn)) /* User write transform | ||
34 | function */ | ||
35 | (png_ptr, /* png_ptr */ | ||
36 | row_info, /* row_info: */ | ||
37 | /* png_uint_32 width; width of row */ | ||
38 | /* png_size_t rowbytes; number of bytes in row */ | ||
39 | /* png_byte color_type; color type of pixels */ | ||
40 | /* png_byte bit_depth; bit depth of samples */ | ||
41 | /* png_byte channels; number of channels (1-4) */ | ||
42 | /* png_byte pixel_depth; bits per pixel (depth*channels) */ | ||
43 | png_ptr->row_buf + 1); /* start of pixel data for row */ | ||
44 | #endif | ||
45 | |||
46 | #ifdef PNG_WRITE_FILLER_SUPPORTED | ||
47 | if (png_ptr->transformations & PNG_FILLER) | ||
48 | png_do_strip_channel(row_info, png_ptr->row_buf + 1, | ||
49 | !(png_ptr->flags & PNG_FLAG_FILLER_AFTER)); | ||
50 | #endif | ||
51 | |||
52 | #ifdef PNG_WRITE_PACKSWAP_SUPPORTED | ||
53 | if (png_ptr->transformations & PNG_PACKSWAP) | ||
54 | png_do_packswap(row_info, png_ptr->row_buf + 1); | ||
55 | #endif | ||
56 | |||
57 | #ifdef PNG_WRITE_PACK_SUPPORTED | ||
58 | if (png_ptr->transformations & PNG_PACK) | ||
59 | png_do_pack(row_info, png_ptr->row_buf + 1, | ||
60 | (png_uint_32)png_ptr->bit_depth); | ||
61 | #endif | ||
62 | |||
63 | #ifdef PNG_WRITE_SWAP_SUPPORTED | ||
64 | if (png_ptr->transformations & PNG_SWAP_BYTES) | ||
65 | png_do_swap(row_info, png_ptr->row_buf + 1); | ||
66 | #endif | ||
67 | |||
68 | #ifdef PNG_WRITE_SHIFT_SUPPORTED | ||
69 | if (png_ptr->transformations & PNG_SHIFT) | ||
70 | png_do_shift(row_info, png_ptr->row_buf + 1, | ||
71 | &(png_ptr->shift)); | ||
72 | #endif | ||
73 | |||
74 | #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED | ||
75 | if (png_ptr->transformations & PNG_SWAP_ALPHA) | ||
76 | png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1); | ||
77 | #endif | ||
78 | |||
79 | #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED | ||
80 | if (png_ptr->transformations & PNG_INVERT_ALPHA) | ||
81 | png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1); | ||
82 | #endif | ||
83 | |||
84 | #ifdef PNG_WRITE_BGR_SUPPORTED | ||
85 | if (png_ptr->transformations & PNG_BGR) | ||
86 | png_do_bgr(row_info, png_ptr->row_buf + 1); | ||
87 | #endif | ||
88 | |||
89 | #ifdef PNG_WRITE_INVERT_SUPPORTED | ||
90 | if (png_ptr->transformations & PNG_INVERT_MONO) | ||
91 | png_do_invert(row_info, png_ptr->row_buf + 1); | ||
92 | #endif | ||
93 | } | ||
94 | |||
95 | #ifdef PNG_WRITE_PACK_SUPPORTED | ||
96 | /* Pack pixels into bytes. Pass the true bit depth in bit_depth. The | ||
97 | * row_info bit depth should be 8 (one pixel per byte). The channels | ||
98 | * should be 1 (this only happens on grayscale and paletted images). | ||
99 | */ | ||
100 | void /* PRIVATE */ | ||
101 | png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth) | ||
102 | { | ||
103 | png_debug(1, "in png_do_pack"); | ||
104 | |||
105 | if (row_info->bit_depth == 8 && | ||
106 | row_info->channels == 1) | ||
107 | { | ||
108 | switch ((int)bit_depth) | ||
109 | { | ||
110 | case 1: | ||
111 | { | ||
112 | png_bytep sp, dp; | ||
113 | int mask, v; | ||
114 | png_uint_32 i; | ||
115 | png_uint_32 row_width = row_info->width; | ||
116 | |||
117 | sp = row; | ||
118 | dp = row; | ||
119 | mask = 0x80; | ||
120 | v = 0; | ||
121 | |||
122 | for (i = 0; i < row_width; i++) | ||
123 | { | ||
124 | if (*sp != 0) | ||
125 | v |= mask; | ||
126 | |||
127 | sp++; | ||
128 | |||
129 | if (mask > 1) | ||
130 | mask >>= 1; | ||
131 | |||
132 | else | ||
133 | { | ||
134 | mask = 0x80; | ||
135 | *dp = (png_byte)v; | ||
136 | dp++; | ||
137 | v = 0; | ||
138 | } | ||
139 | } | ||
140 | |||
141 | if (mask != 0x80) | ||
142 | *dp = (png_byte)v; | ||
143 | |||
144 | break; | ||
145 | } | ||
146 | |||
147 | case 2: | ||
148 | { | ||
149 | png_bytep sp, dp; | ||
150 | int shift, v; | ||
151 | png_uint_32 i; | ||
152 | png_uint_32 row_width = row_info->width; | ||
153 | |||
154 | sp = row; | ||
155 | dp = row; | ||
156 | shift = 6; | ||
157 | v = 0; | ||
158 | |||
159 | for (i = 0; i < row_width; i++) | ||
160 | { | ||
161 | png_byte value; | ||
162 | |||
163 | value = (png_byte)(*sp & 0x03); | ||
164 | v |= (value << shift); | ||
165 | |||
166 | if (shift == 0) | ||
167 | { | ||
168 | shift = 6; | ||
169 | *dp = (png_byte)v; | ||
170 | dp++; | ||
171 | v = 0; | ||
172 | } | ||
173 | |||
174 | else | ||
175 | shift -= 2; | ||
176 | |||
177 | sp++; | ||
178 | } | ||
179 | |||
180 | if (shift != 6) | ||
181 | *dp = (png_byte)v; | ||
182 | |||
183 | break; | ||
184 | } | ||
185 | |||
186 | case 4: | ||
187 | { | ||
188 | png_bytep sp, dp; | ||
189 | int shift, v; | ||
190 | png_uint_32 i; | ||
191 | png_uint_32 row_width = row_info->width; | ||
192 | |||
193 | sp = row; | ||
194 | dp = row; | ||
195 | shift = 4; | ||
196 | v = 0; | ||
197 | |||
198 | for (i = 0; i < row_width; i++) | ||
199 | { | ||
200 | png_byte value; | ||
201 | |||
202 | value = (png_byte)(*sp & 0x0f); | ||
203 | v |= (value << shift); | ||
204 | |||
205 | if (shift == 0) | ||
206 | { | ||
207 | shift = 4; | ||
208 | *dp = (png_byte)v; | ||
209 | dp++; | ||
210 | v = 0; | ||
211 | } | ||
212 | |||
213 | else | ||
214 | shift -= 4; | ||
215 | |||
216 | sp++; | ||
217 | } | ||
218 | |||
219 | if (shift != 4) | ||
220 | *dp = (png_byte)v; | ||
221 | |||
222 | break; | ||
223 | } | ||
224 | |||
225 | default: | ||
226 | break; | ||
227 | } | ||
228 | |||
229 | row_info->bit_depth = (png_byte)bit_depth; | ||
230 | row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels); | ||
231 | row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, | ||
232 | row_info->width); | ||
233 | } | ||
234 | } | ||
235 | #endif | ||
236 | |||
237 | #ifdef PNG_WRITE_SHIFT_SUPPORTED | ||
238 | /* Shift pixel values to take advantage of whole range. Pass the | ||
239 | * true number of bits in bit_depth. The row should be packed | ||
240 | * according to row_info->bit_depth. Thus, if you had a row of | ||
241 | * bit depth 4, but the pixels only had values from 0 to 7, you | ||
242 | * would pass 3 as bit_depth, and this routine would translate the | ||
243 | * data to 0 to 15. | ||
244 | */ | ||
245 | void /* PRIVATE */ | ||
246 | png_do_shift(png_row_infop row_info, png_bytep row, | ||
247 | png_const_color_8p bit_depth) | ||
248 | { | ||
249 | png_debug(1, "in png_do_shift"); | ||
250 | |||
251 | if (row_info->color_type != PNG_COLOR_TYPE_PALETTE) | ||
252 | { | ||
253 | int shift_start[4], shift_dec[4]; | ||
254 | int channels = 0; | ||
255 | |||
256 | if (row_info->color_type & PNG_COLOR_MASK_COLOR) | ||
257 | { | ||
258 | shift_start[channels] = row_info->bit_depth - bit_depth->red; | ||
259 | shift_dec[channels] = bit_depth->red; | ||
260 | channels++; | ||
261 | |||
262 | shift_start[channels] = row_info->bit_depth - bit_depth->green; | ||
263 | shift_dec[channels] = bit_depth->green; | ||
264 | channels++; | ||
265 | |||
266 | shift_start[channels] = row_info->bit_depth - bit_depth->blue; | ||
267 | shift_dec[channels] = bit_depth->blue; | ||
268 | channels++; | ||
269 | } | ||
270 | |||
271 | else | ||
272 | { | ||
273 | shift_start[channels] = row_info->bit_depth - bit_depth->gray; | ||
274 | shift_dec[channels] = bit_depth->gray; | ||
275 | channels++; | ||
276 | } | ||
277 | |||
278 | if (row_info->color_type & PNG_COLOR_MASK_ALPHA) | ||
279 | { | ||
280 | shift_start[channels] = row_info->bit_depth - bit_depth->alpha; | ||
281 | shift_dec[channels] = bit_depth->alpha; | ||
282 | channels++; | ||
283 | } | ||
284 | |||
285 | /* With low row depths, could only be grayscale, so one channel */ | ||
286 | if (row_info->bit_depth < 8) | ||
287 | { | ||
288 | png_bytep bp = row; | ||
289 | png_size_t i; | ||
290 | png_byte mask; | ||
291 | png_size_t row_bytes = row_info->rowbytes; | ||
292 | |||
293 | if (bit_depth->gray == 1 && row_info->bit_depth == 2) | ||
294 | mask = 0x55; | ||
295 | |||
296 | else if (row_info->bit_depth == 4 && bit_depth->gray == 3) | ||
297 | mask = 0x11; | ||
298 | |||
299 | else | ||
300 | mask = 0xff; | ||
301 | |||
302 | for (i = 0; i < row_bytes; i++, bp++) | ||
303 | { | ||
304 | png_uint_16 v; | ||
305 | int j; | ||
306 | |||
307 | v = *bp; | ||
308 | *bp = 0; | ||
309 | |||
310 | for (j = shift_start[0]; j > -shift_dec[0]; j -= shift_dec[0]) | ||
311 | { | ||
312 | if (j > 0) | ||
313 | *bp |= (png_byte)((v << j) & 0xff); | ||
314 | |||
315 | else | ||
316 | *bp |= (png_byte)((v >> (-j)) & mask); | ||
317 | } | ||
318 | } | ||
319 | } | ||
320 | |||
321 | else if (row_info->bit_depth == 8) | ||
322 | { | ||
323 | png_bytep bp = row; | ||
324 | png_uint_32 i; | ||
325 | png_uint_32 istop = channels * row_info->width; | ||
326 | |||
327 | for (i = 0; i < istop; i++, bp++) | ||
328 | { | ||
329 | |||
330 | png_uint_16 v; | ||
331 | int j; | ||
332 | int c = (int)(i%channels); | ||
333 | |||
334 | v = *bp; | ||
335 | *bp = 0; | ||
336 | |||
337 | for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) | ||
338 | { | ||
339 | if (j > 0) | ||
340 | *bp |= (png_byte)((v << j) & 0xff); | ||
341 | |||
342 | else | ||
343 | *bp |= (png_byte)((v >> (-j)) & 0xff); | ||
344 | } | ||
345 | } | ||
346 | } | ||
347 | |||
348 | else | ||
349 | { | ||
350 | png_bytep bp; | ||
351 | png_uint_32 i; | ||
352 | png_uint_32 istop = channels * row_info->width; | ||
353 | |||
354 | for (bp = row, i = 0; i < istop; i++) | ||
355 | { | ||
356 | int c = (int)(i%channels); | ||
357 | png_uint_16 value, v; | ||
358 | int j; | ||
359 | |||
360 | v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1)); | ||
361 | value = 0; | ||
362 | |||
363 | for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c]) | ||
364 | { | ||
365 | if (j > 0) | ||
366 | value |= (png_uint_16)((v << j) & (png_uint_16)0xffff); | ||
367 | |||
368 | else | ||
369 | value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff); | ||
370 | } | ||
371 | *bp++ = (png_byte)(value >> 8); | ||
372 | *bp++ = (png_byte)(value & 0xff); | ||
373 | } | ||
374 | } | ||
375 | } | ||
376 | } | ||
377 | #endif | ||
378 | |||
379 | #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED | ||
380 | void /* PRIVATE */ | ||
381 | png_do_write_swap_alpha(png_row_infop row_info, png_bytep row) | ||
382 | { | ||
383 | png_debug(1, "in png_do_write_swap_alpha"); | ||
384 | |||
385 | { | ||
386 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) | ||
387 | { | ||
388 | if (row_info->bit_depth == 8) | ||
389 | { | ||
390 | /* This converts from ARGB to RGBA */ | ||
391 | png_bytep sp, dp; | ||
392 | png_uint_32 i; | ||
393 | png_uint_32 row_width = row_info->width; | ||
394 | |||
395 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
396 | { | ||
397 | png_byte save = *(sp++); | ||
398 | *(dp++) = *(sp++); | ||
399 | *(dp++) = *(sp++); | ||
400 | *(dp++) = *(sp++); | ||
401 | *(dp++) = save; | ||
402 | } | ||
403 | } | ||
404 | |||
405 | #ifdef PNG_WRITE_16BIT_SUPPORTED | ||
406 | else | ||
407 | { | ||
408 | /* This converts from AARRGGBB to RRGGBBAA */ | ||
409 | png_bytep sp, dp; | ||
410 | png_uint_32 i; | ||
411 | png_uint_32 row_width = row_info->width; | ||
412 | |||
413 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
414 | { | ||
415 | png_byte save[2]; | ||
416 | save[0] = *(sp++); | ||
417 | save[1] = *(sp++); | ||
418 | *(dp++) = *(sp++); | ||
419 | *(dp++) = *(sp++); | ||
420 | *(dp++) = *(sp++); | ||
421 | *(dp++) = *(sp++); | ||
422 | *(dp++) = *(sp++); | ||
423 | *(dp++) = *(sp++); | ||
424 | *(dp++) = save[0]; | ||
425 | *(dp++) = save[1]; | ||
426 | } | ||
427 | } | ||
428 | #endif /* PNG_WRITE_16BIT_SUPPORTED */ | ||
429 | } | ||
430 | |||
431 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) | ||
432 | { | ||
433 | if (row_info->bit_depth == 8) | ||
434 | { | ||
435 | /* This converts from AG to GA */ | ||
436 | png_bytep sp, dp; | ||
437 | png_uint_32 i; | ||
438 | png_uint_32 row_width = row_info->width; | ||
439 | |||
440 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
441 | { | ||
442 | png_byte save = *(sp++); | ||
443 | *(dp++) = *(sp++); | ||
444 | *(dp++) = save; | ||
445 | } | ||
446 | } | ||
447 | |||
448 | #ifdef PNG_WRITE_16BIT_SUPPORTED | ||
449 | else | ||
450 | { | ||
451 | /* This converts from AAGG to GGAA */ | ||
452 | png_bytep sp, dp; | ||
453 | png_uint_32 i; | ||
454 | png_uint_32 row_width = row_info->width; | ||
455 | |||
456 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
457 | { | ||
458 | png_byte save[2]; | ||
459 | save[0] = *(sp++); | ||
460 | save[1] = *(sp++); | ||
461 | *(dp++) = *(sp++); | ||
462 | *(dp++) = *(sp++); | ||
463 | *(dp++) = save[0]; | ||
464 | *(dp++) = save[1]; | ||
465 | } | ||
466 | } | ||
467 | #endif /* PNG_WRITE_16BIT_SUPPORTED */ | ||
468 | } | ||
469 | } | ||
470 | } | ||
471 | #endif | ||
472 | |||
473 | #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED | ||
474 | void /* PRIVATE */ | ||
475 | png_do_write_invert_alpha(png_row_infop row_info, png_bytep row) | ||
476 | { | ||
477 | png_debug(1, "in png_do_write_invert_alpha"); | ||
478 | |||
479 | { | ||
480 | if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) | ||
481 | { | ||
482 | if (row_info->bit_depth == 8) | ||
483 | { | ||
484 | /* This inverts the alpha channel in RGBA */ | ||
485 | png_bytep sp, dp; | ||
486 | png_uint_32 i; | ||
487 | png_uint_32 row_width = row_info->width; | ||
488 | |||
489 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
490 | { | ||
491 | /* Does nothing | ||
492 | *(dp++) = *(sp++); | ||
493 | *(dp++) = *(sp++); | ||
494 | *(dp++) = *(sp++); | ||
495 | */ | ||
496 | sp+=3; dp = sp; | ||
497 | *(dp++) = (png_byte)(255 - *(sp++)); | ||
498 | } | ||
499 | } | ||
500 | |||
501 | #ifdef PNG_WRITE_16BIT_SUPPORTED | ||
502 | else | ||
503 | { | ||
504 | /* This inverts the alpha channel in RRGGBBAA */ | ||
505 | png_bytep sp, dp; | ||
506 | png_uint_32 i; | ||
507 | png_uint_32 row_width = row_info->width; | ||
508 | |||
509 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
510 | { | ||
511 | /* Does nothing | ||
512 | *(dp++) = *(sp++); | ||
513 | *(dp++) = *(sp++); | ||
514 | *(dp++) = *(sp++); | ||
515 | *(dp++) = *(sp++); | ||
516 | *(dp++) = *(sp++); | ||
517 | *(dp++) = *(sp++); | ||
518 | */ | ||
519 | sp+=6; dp = sp; | ||
520 | *(dp++) = (png_byte)(255 - *(sp++)); | ||
521 | *(dp++) = (png_byte)(255 - *(sp++)); | ||
522 | } | ||
523 | } | ||
524 | #endif /* PNG_WRITE_16BIT_SUPPORTED */ | ||
525 | } | ||
526 | |||
527 | else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) | ||
528 | { | ||
529 | if (row_info->bit_depth == 8) | ||
530 | { | ||
531 | /* This inverts the alpha channel in GA */ | ||
532 | png_bytep sp, dp; | ||
533 | png_uint_32 i; | ||
534 | png_uint_32 row_width = row_info->width; | ||
535 | |||
536 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
537 | { | ||
538 | *(dp++) = *(sp++); | ||
539 | *(dp++) = (png_byte)(255 - *(sp++)); | ||
540 | } | ||
541 | } | ||
542 | |||
543 | #ifdef PNG_WRITE_16BIT_SUPPORTED | ||
544 | else | ||
545 | { | ||
546 | /* This inverts the alpha channel in GGAA */ | ||
547 | png_bytep sp, dp; | ||
548 | png_uint_32 i; | ||
549 | png_uint_32 row_width = row_info->width; | ||
550 | |||
551 | for (i = 0, sp = dp = row; i < row_width; i++) | ||
552 | { | ||
553 | /* Does nothing | ||
554 | *(dp++) = *(sp++); | ||
555 | *(dp++) = *(sp++); | ||
556 | */ | ||
557 | sp+=2; dp = sp; | ||
558 | *(dp++) = (png_byte)(255 - *(sp++)); | ||
559 | *(dp++) = (png_byte)(255 - *(sp++)); | ||
560 | } | ||
561 | } | ||
562 | #endif /* PNG_WRITE_16BIT_SUPPORTED */ | ||
563 | } | ||
564 | } | ||
565 | } | ||
566 | #endif | ||
567 | #endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */ | ||
568 | |||
569 | #ifdef PNG_MNG_FEATURES_SUPPORTED | ||
570 | /* Undoes intrapixel differencing */ | ||
571 | void /* PRIVATE */ | ||
572 | png_do_write_intrapixel(png_row_infop row_info, png_bytep row) | ||
573 | { | ||
574 | png_debug(1, "in png_do_write_intrapixel"); | ||
575 | |||
576 | if ((row_info->color_type & PNG_COLOR_MASK_COLOR)) | ||
577 | { | ||
578 | int bytes_per_pixel; | ||
579 | png_uint_32 row_width = row_info->width; | ||
580 | if (row_info->bit_depth == 8) | ||
581 | { | ||
582 | png_bytep rp; | ||
583 | png_uint_32 i; | ||
584 | |||
585 | if (row_info->color_type == PNG_COLOR_TYPE_RGB) | ||
586 | bytes_per_pixel = 3; | ||
587 | |||
588 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) | ||
589 | bytes_per_pixel = 4; | ||
590 | |||
591 | else | ||
592 | return; | ||
593 | |||
594 | for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) | ||
595 | { | ||
596 | *(rp) = (png_byte)((*rp - *(rp + 1)) & 0xff); | ||
597 | *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff); | ||
598 | } | ||
599 | } | ||
600 | |||
601 | #ifdef PNG_WRITE_16BIT_SUPPORTED | ||
602 | else if (row_info->bit_depth == 16) | ||
603 | { | ||
604 | png_bytep rp; | ||
605 | png_uint_32 i; | ||
606 | |||
607 | if (row_info->color_type == PNG_COLOR_TYPE_RGB) | ||
608 | bytes_per_pixel = 6; | ||
609 | |||
610 | else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA) | ||
611 | bytes_per_pixel = 8; | ||
612 | |||
613 | else | ||
614 | return; | ||
615 | |||
616 | for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel) | ||
617 | { | ||
618 | png_uint_32 s0 = (*(rp ) << 8) | *(rp + 1); | ||
619 | png_uint_32 s1 = (*(rp + 2) << 8) | *(rp + 3); | ||
620 | png_uint_32 s2 = (*(rp + 4) << 8) | *(rp + 5); | ||
621 | png_uint_32 red = (png_uint_32)((s0 - s1) & 0xffffL); | ||
622 | png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL); | ||
623 | *(rp ) = (png_byte)((red >> 8) & 0xff); | ||
624 | *(rp + 1) = (png_byte)(red & 0xff); | ||
625 | *(rp + 4) = (png_byte)((blue >> 8) & 0xff); | ||
626 | *(rp + 5) = (png_byte)(blue & 0xff); | ||
627 | } | ||
628 | } | ||
629 | #endif /* PNG_WRITE_16BIT_SUPPORTED */ | ||
630 | } | ||
631 | } | ||
632 | #endif /* PNG_MNG_FEATURES_SUPPORTED */ | ||
633 | #endif /* PNG_WRITE_SUPPORTED */ | ||