]>
Commit | Line | Data |
---|---|---|
1 | ||
2 | /* pngread.c - read a PNG file | |
3 | * | |
4 | * Last changed in libpng 1.2.19 August 19, 2007 | |
5 | * For conditions of distribution and use, see copyright notice in png.h | |
6 | * Copyright (c) 1998-2007 Glenn Randers-Pehrson | |
7 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) | |
8 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) | |
9 | * | |
10 | * This file contains routines that an application calls directly to | |
11 | * read a PNG file or stream. | |
12 | */ | |
13 | ||
14 | #define PNG_INTERNAL | |
15 | #include "png.h" | |
16 | ||
17 | #if defined(PNG_READ_SUPPORTED) | |
18 | ||
19 | /* Create a PNG structure for reading, and allocate any memory needed. */ | |
20 | png_structp PNGAPI | |
21 | png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr, | |
22 | png_error_ptr error_fn, png_error_ptr warn_fn) | |
23 | { | |
24 | ||
25 | #ifdef PNG_USER_MEM_SUPPORTED | |
26 | return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn, | |
27 | warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL)); | |
28 | } | |
29 | ||
30 | /* Alternate create PNG structure for reading, and allocate any memory needed. */ | |
31 | png_structp PNGAPI | |
32 | png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr, | |
33 | png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, | |
34 | png_malloc_ptr malloc_fn, png_free_ptr free_fn) | |
35 | { | |
36 | #endif /* PNG_USER_MEM_SUPPORTED */ | |
37 | ||
38 | png_structp png_ptr; | |
39 | ||
40 | #ifdef PNG_SETJMP_SUPPORTED | |
41 | #ifdef USE_FAR_KEYWORD | |
42 | jmp_buf jmpbuf; | |
43 | #endif | |
44 | #endif | |
45 | ||
46 | int i; | |
47 | ||
48 | png_debug(1, "in png_create_read_struct\n"); | |
49 | #ifdef PNG_USER_MEM_SUPPORTED | |
50 | png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, | |
51 | (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr); | |
52 | #else | |
53 | png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); | |
54 | #endif | |
55 | if (png_ptr == NULL) | |
56 | return (NULL); | |
57 | ||
58 | /* added at libpng-1.2.6 */ | |
59 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED | |
60 | png_ptr->user_width_max=PNG_USER_WIDTH_MAX; | |
61 | png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; | |
62 | #endif | |
63 | ||
64 | #ifdef PNG_SETJMP_SUPPORTED | |
65 | #ifdef USE_FAR_KEYWORD | |
66 | if (setjmp(jmpbuf)) | |
67 | #else | |
68 | if (setjmp(png_ptr->jmpbuf)) | |
69 | #endif | |
70 | { | |
71 | png_free(png_ptr, png_ptr->zbuf); | |
72 | png_ptr->zbuf=NULL; | |
73 | #ifdef PNG_USER_MEM_SUPPORTED | |
74 | png_destroy_struct_2((png_voidp)png_ptr, | |
75 | (png_free_ptr)free_fn, (png_voidp)mem_ptr); | |
76 | #else | |
77 | png_destroy_struct((png_voidp)png_ptr); | |
78 | #endif | |
79 | return (NULL); | |
80 | } | |
81 | #ifdef USE_FAR_KEYWORD | |
82 | png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf)); | |
83 | #endif | |
84 | #endif | |
85 | ||
86 | #ifdef PNG_USER_MEM_SUPPORTED | |
87 | png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); | |
88 | #endif | |
89 | ||
90 | png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); | |
91 | ||
92 | i=0; | |
93 | do | |
94 | { | |
95 | if(user_png_ver[i] != png_libpng_ver[i]) | |
96 | png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; | |
97 | } while (png_libpng_ver[i++]); | |
98 | ||
99 | if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) | |
100 | { | |
101 | /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so | |
102 | * we must recompile any applications that use any older library version. | |
103 | * For versions after libpng 1.0, we will be compatible, so we need | |
104 | * only check the first digit. | |
105 | */ | |
106 | if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || | |
107 | (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || | |
108 | (user_png_ver[0] == '0' && user_png_ver[2] < '9')) | |
109 | { | |
110 | #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) | |
111 | char msg[80]; | |
112 | if (user_png_ver) | |
113 | { | |
114 | png_snprintf(msg, 80, | |
115 | "Application was compiled with png.h from libpng-%.20s", | |
116 | user_png_ver); | |
117 | png_warning(png_ptr, msg); | |
118 | } | |
119 | png_snprintf(msg, 80, | |
120 | "Application is running with png.c from libpng-%.20s", | |
121 | png_libpng_ver); | |
122 | png_warning(png_ptr, msg); | |
123 | #endif | |
124 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
125 | png_ptr->flags=0; | |
126 | #endif | |
127 | png_error(png_ptr, | |
128 | "Incompatible libpng version in application and library"); | |
129 | } | |
130 | } | |
131 | ||
132 | /* initialize zbuf - compression buffer */ | |
133 | png_ptr->zbuf_size = PNG_ZBUF_SIZE; | |
134 | png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, | |
135 | (png_uint_32)png_ptr->zbuf_size); | |
136 | png_ptr->zstream.zalloc = png_zalloc; | |
137 | png_ptr->zstream.zfree = png_zfree; | |
138 | png_ptr->zstream.opaque = (voidpf)png_ptr; | |
139 | ||
140 | switch (inflateInit(&png_ptr->zstream)) | |
141 | { | |
142 | case Z_OK: /* Do nothing */ break; | |
143 | case Z_MEM_ERROR: | |
144 | case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break; | |
145 | case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break; | |
146 | default: png_error(png_ptr, "Unknown zlib error"); | |
147 | } | |
148 | ||
149 | png_ptr->zstream.next_out = png_ptr->zbuf; | |
150 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; | |
151 | ||
152 | png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); | |
153 | ||
154 | #ifdef PNG_SETJMP_SUPPORTED | |
155 | /* Applications that neglect to set up their own setjmp() and then encounter | |
156 | a png_error() will longjmp here. Since the jmpbuf is then meaningless we | |
157 | abort instead of returning. */ | |
158 | #ifdef USE_FAR_KEYWORD | |
159 | if (setjmp(jmpbuf)) | |
160 | PNG_ABORT(); | |
161 | png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf)); | |
162 | #else | |
163 | if (setjmp(png_ptr->jmpbuf)) | |
164 | PNG_ABORT(); | |
165 | #endif | |
166 | #endif | |
167 | return (png_ptr); | |
168 | } | |
169 | ||
170 | #if defined(PNG_1_0_X) || defined(PNG_1_2_X) | |
171 | /* Initialize PNG structure for reading, and allocate any memory needed. | |
172 | This interface is deprecated in favour of the png_create_read_struct(), | |
173 | and it will disappear as of libpng-1.3.0. */ | |
174 | #undef png_read_init | |
175 | void PNGAPI | |
176 | png_read_init(png_structp png_ptr) | |
177 | { | |
178 | /* We only come here via pre-1.0.7-compiled applications */ | |
179 | png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0); | |
180 | } | |
181 | ||
182 | void PNGAPI | |
183 | png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver, | |
184 | png_size_t png_struct_size, png_size_t png_info_size) | |
185 | { | |
186 | /* We only come here via pre-1.0.12-compiled applications */ | |
187 | if(png_ptr == NULL) return; | |
188 | #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) | |
189 | if(png_sizeof(png_struct) > png_struct_size || | |
190 | png_sizeof(png_info) > png_info_size) | |
191 | { | |
192 | char msg[80]; | |
193 | png_ptr->warning_fn=NULL; | |
194 | if (user_png_ver) | |
195 | { | |
196 | png_snprintf(msg, 80, | |
197 | "Application was compiled with png.h from libpng-%.20s", | |
198 | user_png_ver); | |
199 | png_warning(png_ptr, msg); | |
200 | } | |
201 | png_snprintf(msg, 80, | |
202 | "Application is running with png.c from libpng-%.20s", | |
203 | png_libpng_ver); | |
204 | png_warning(png_ptr, msg); | |
205 | } | |
206 | #endif | |
207 | if(png_sizeof(png_struct) > png_struct_size) | |
208 | { | |
209 | png_ptr->error_fn=NULL; | |
210 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
211 | png_ptr->flags=0; | |
212 | #endif | |
213 | png_error(png_ptr, | |
214 | "The png struct allocated by the application for reading is too small."); | |
215 | } | |
216 | if(png_sizeof(png_info) > png_info_size) | |
217 | { | |
218 | png_ptr->error_fn=NULL; | |
219 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
220 | png_ptr->flags=0; | |
221 | #endif | |
222 | png_error(png_ptr, | |
223 | "The info struct allocated by application for reading is too small."); | |
224 | } | |
225 | png_read_init_3(&png_ptr, user_png_ver, png_struct_size); | |
226 | } | |
227 | #endif /* PNG_1_0_X || PNG_1_2_X */ | |
228 | ||
229 | void PNGAPI | |
230 | png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver, | |
231 | png_size_t png_struct_size) | |
232 | { | |
233 | #ifdef PNG_SETJMP_SUPPORTED | |
234 | jmp_buf tmp_jmp; /* to save current jump buffer */ | |
235 | #endif | |
236 | ||
237 | int i=0; | |
238 | ||
239 | png_structp png_ptr=*ptr_ptr; | |
240 | ||
241 | if(png_ptr == NULL) return; | |
242 | ||
243 | do | |
244 | { | |
245 | if(user_png_ver[i] != png_libpng_ver[i]) | |
246 | { | |
247 | #ifdef PNG_LEGACY_SUPPORTED | |
248 | png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; | |
249 | #else | |
250 | png_ptr->warning_fn=NULL; | |
251 | png_warning(png_ptr, | |
252 | "Application uses deprecated png_read_init() and should be recompiled."); | |
253 | break; | |
254 | #endif | |
255 | } | |
256 | } while (png_libpng_ver[i++]); | |
257 | ||
258 | png_debug(1, "in png_read_init_3\n"); | |
259 | ||
260 | #ifdef PNG_SETJMP_SUPPORTED | |
261 | /* save jump buffer and error functions */ | |
262 | png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf)); | |
263 | #endif | |
264 | ||
265 | if(png_sizeof(png_struct) > png_struct_size) | |
266 | { | |
267 | png_destroy_struct(png_ptr); | |
268 | *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); | |
269 | png_ptr = *ptr_ptr; | |
270 | } | |
271 | ||
272 | /* reset all variables to 0 */ | |
273 | png_memset(png_ptr, 0, png_sizeof (png_struct)); | |
274 | ||
275 | #ifdef PNG_SETJMP_SUPPORTED | |
276 | /* restore jump buffer */ | |
277 | png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf)); | |
278 | #endif | |
279 | ||
280 | /* added at libpng-1.2.6 */ | |
281 | #ifdef PNG_SET_USER_LIMITS_SUPPORTED | |
282 | png_ptr->user_width_max=PNG_USER_WIDTH_MAX; | |
283 | png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; | |
284 | #endif | |
285 | ||
286 | /* initialize zbuf - compression buffer */ | |
287 | png_ptr->zbuf_size = PNG_ZBUF_SIZE; | |
288 | png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, | |
289 | (png_uint_32)png_ptr->zbuf_size); | |
290 | png_ptr->zstream.zalloc = png_zalloc; | |
291 | png_ptr->zstream.zfree = png_zfree; | |
292 | png_ptr->zstream.opaque = (voidpf)png_ptr; | |
293 | ||
294 | switch (inflateInit(&png_ptr->zstream)) | |
295 | { | |
296 | case Z_OK: /* Do nothing */ break; | |
297 | case Z_MEM_ERROR: | |
298 | case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break; | |
299 | case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break; | |
300 | default: png_error(png_ptr, "Unknown zlib error"); | |
301 | } | |
302 | ||
303 | png_ptr->zstream.next_out = png_ptr->zbuf; | |
304 | png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; | |
305 | ||
306 | png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); | |
307 | } | |
308 | ||
309 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
310 | /* Read the information before the actual image data. This has been | |
311 | * changed in v0.90 to allow reading a file that already has the magic | |
312 | * bytes read from the stream. You can tell libpng how many bytes have | |
313 | * been read from the beginning of the stream (up to the maximum of 8) | |
314 | * via png_set_sig_bytes(), and we will only check the remaining bytes | |
315 | * here. The application can then have access to the signature bytes we | |
316 | * read if it is determined that this isn't a valid PNG file. | |
317 | */ | |
318 | void PNGAPI | |
319 | png_read_info(png_structp png_ptr, png_infop info_ptr) | |
320 | { | |
321 | if(png_ptr == NULL) return; | |
322 | png_debug(1, "in png_read_info\n"); | |
323 | /* If we haven't checked all of the PNG signature bytes, do so now. */ | |
324 | if (png_ptr->sig_bytes < 8) | |
325 | { | |
326 | png_size_t num_checked = png_ptr->sig_bytes, | |
327 | num_to_check = 8 - num_checked; | |
328 | ||
329 | png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); | |
330 | png_ptr->sig_bytes = 8; | |
331 | ||
332 | if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) | |
333 | { | |
334 | if (num_checked < 4 && | |
335 | png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) | |
336 | png_error(png_ptr, "Not a PNG file"); | |
337 | else | |
338 | png_error(png_ptr, "PNG file corrupted by ASCII conversion"); | |
339 | } | |
340 | if (num_checked < 3) | |
341 | png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; | |
342 | } | |
343 | ||
344 | for(;;) | |
345 | { | |
346 | #ifdef PNG_USE_LOCAL_ARRAYS | |
347 | PNG_CONST PNG_IHDR; | |
348 | PNG_CONST PNG_IDAT; | |
349 | PNG_CONST PNG_IEND; | |
350 | PNG_CONST PNG_PLTE; | |
351 | #if defined(PNG_READ_bKGD_SUPPORTED) | |
352 | PNG_CONST PNG_bKGD; | |
353 | #endif | |
354 | #if defined(PNG_READ_cHRM_SUPPORTED) | |
355 | PNG_CONST PNG_cHRM; | |
356 | #endif | |
357 | #if defined(PNG_READ_gAMA_SUPPORTED) | |
358 | PNG_CONST PNG_gAMA; | |
359 | #endif | |
360 | #if defined(PNG_READ_hIST_SUPPORTED) | |
361 | PNG_CONST PNG_hIST; | |
362 | #endif | |
363 | #if defined(PNG_READ_iCCP_SUPPORTED) | |
364 | PNG_CONST PNG_iCCP; | |
365 | #endif | |
366 | #if defined(PNG_READ_iTXt_SUPPORTED) | |
367 | PNG_CONST PNG_iTXt; | |
368 | #endif | |
369 | #if defined(PNG_READ_oFFs_SUPPORTED) | |
370 | PNG_CONST PNG_oFFs; | |
371 | #endif | |
372 | #if defined(PNG_READ_pCAL_SUPPORTED) | |
373 | PNG_CONST PNG_pCAL; | |
374 | #endif | |
375 | #if defined(PNG_READ_pHYs_SUPPORTED) | |
376 | PNG_CONST PNG_pHYs; | |
377 | #endif | |
378 | #if defined(PNG_READ_sBIT_SUPPORTED) | |
379 | PNG_CONST PNG_sBIT; | |
380 | #endif | |
381 | #if defined(PNG_READ_sCAL_SUPPORTED) | |
382 | PNG_CONST PNG_sCAL; | |
383 | #endif | |
384 | #if defined(PNG_READ_sPLT_SUPPORTED) | |
385 | PNG_CONST PNG_sPLT; | |
386 | #endif | |
387 | #if defined(PNG_READ_sRGB_SUPPORTED) | |
388 | PNG_CONST PNG_sRGB; | |
389 | #endif | |
390 | #if defined(PNG_READ_tEXt_SUPPORTED) | |
391 | PNG_CONST PNG_tEXt; | |
392 | #endif | |
393 | #if defined(PNG_READ_tIME_SUPPORTED) | |
394 | PNG_CONST PNG_tIME; | |
395 | #endif | |
396 | #if defined(PNG_READ_tRNS_SUPPORTED) | |
397 | PNG_CONST PNG_tRNS; | |
398 | #endif | |
399 | #if defined(PNG_READ_zTXt_SUPPORTED) | |
400 | PNG_CONST PNG_zTXt; | |
401 | #endif | |
402 | #endif /* PNG_USE_LOCAL_ARRAYS */ | |
403 | png_byte chunk_length[4]; | |
404 | png_uint_32 length; | |
405 | ||
406 | png_read_data(png_ptr, chunk_length, 4); | |
407 | length = png_get_uint_31(png_ptr,chunk_length); | |
408 | ||
409 | png_reset_crc(png_ptr); | |
410 | png_crc_read(png_ptr, png_ptr->chunk_name, 4); | |
411 | ||
412 | png_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name, | |
413 | length); | |
414 | ||
415 | /* This should be a binary subdivision search or a hash for | |
416 | * matching the chunk name rather than a linear search. | |
417 | */ | |
418 | if (!png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4)) | |
419 | if(png_ptr->mode & PNG_AFTER_IDAT) | |
420 | png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; | |
421 | ||
422 | if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) | |
423 | png_handle_IHDR(png_ptr, info_ptr, length); | |
424 | else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) | |
425 | png_handle_IEND(png_ptr, info_ptr, length); | |
426 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED | |
427 | else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) | |
428 | { | |
429 | if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) | |
430 | png_ptr->mode |= PNG_HAVE_IDAT; | |
431 | png_handle_unknown(png_ptr, info_ptr, length); | |
432 | if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) | |
433 | png_ptr->mode |= PNG_HAVE_PLTE; | |
434 | else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) | |
435 | { | |
436 | if (!(png_ptr->mode & PNG_HAVE_IHDR)) | |
437 | png_error(png_ptr, "Missing IHDR before IDAT"); | |
438 | else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && | |
439 | !(png_ptr->mode & PNG_HAVE_PLTE)) | |
440 | png_error(png_ptr, "Missing PLTE before IDAT"); | |
441 | break; | |
442 | } | |
443 | } | |
444 | #endif | |
445 | else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) | |
446 | png_handle_PLTE(png_ptr, info_ptr, length); | |
447 | else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) | |
448 | { | |
449 | if (!(png_ptr->mode & PNG_HAVE_IHDR)) | |
450 | png_error(png_ptr, "Missing IHDR before IDAT"); | |
451 | else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && | |
452 | !(png_ptr->mode & PNG_HAVE_PLTE)) | |
453 | png_error(png_ptr, "Missing PLTE before IDAT"); | |
454 | ||
455 | png_ptr->idat_size = length; | |
456 | png_ptr->mode |= PNG_HAVE_IDAT; | |
457 | break; | |
458 | } | |
459 | #if defined(PNG_READ_bKGD_SUPPORTED) | |
460 | else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) | |
461 | png_handle_bKGD(png_ptr, info_ptr, length); | |
462 | #endif | |
463 | #if defined(PNG_READ_cHRM_SUPPORTED) | |
464 | else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) | |
465 | png_handle_cHRM(png_ptr, info_ptr, length); | |
466 | #endif | |
467 | #if defined(PNG_READ_gAMA_SUPPORTED) | |
468 | else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) | |
469 | png_handle_gAMA(png_ptr, info_ptr, length); | |
470 | #endif | |
471 | #if defined(PNG_READ_hIST_SUPPORTED) | |
472 | else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) | |
473 | png_handle_hIST(png_ptr, info_ptr, length); | |
474 | #endif | |
475 | #if defined(PNG_READ_oFFs_SUPPORTED) | |
476 | else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) | |
477 | png_handle_oFFs(png_ptr, info_ptr, length); | |
478 | #endif | |
479 | #if defined(PNG_READ_pCAL_SUPPORTED) | |
480 | else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) | |
481 | png_handle_pCAL(png_ptr, info_ptr, length); | |
482 | #endif | |
483 | #if defined(PNG_READ_sCAL_SUPPORTED) | |
484 | else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) | |
485 | png_handle_sCAL(png_ptr, info_ptr, length); | |
486 | #endif | |
487 | #if defined(PNG_READ_pHYs_SUPPORTED) | |
488 | else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) | |
489 | png_handle_pHYs(png_ptr, info_ptr, length); | |
490 | #endif | |
491 | #if defined(PNG_READ_sBIT_SUPPORTED) | |
492 | else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) | |
493 | png_handle_sBIT(png_ptr, info_ptr, length); | |
494 | #endif | |
495 | #if defined(PNG_READ_sRGB_SUPPORTED) | |
496 | else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) | |
497 | png_handle_sRGB(png_ptr, info_ptr, length); | |
498 | #endif | |
499 | #if defined(PNG_READ_iCCP_SUPPORTED) | |
500 | else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) | |
501 | png_handle_iCCP(png_ptr, info_ptr, length); | |
502 | #endif | |
503 | #if defined(PNG_READ_sPLT_SUPPORTED) | |
504 | else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) | |
505 | png_handle_sPLT(png_ptr, info_ptr, length); | |
506 | #endif | |
507 | #if defined(PNG_READ_tEXt_SUPPORTED) | |
508 | else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) | |
509 | png_handle_tEXt(png_ptr, info_ptr, length); | |
510 | #endif | |
511 | #if defined(PNG_READ_tIME_SUPPORTED) | |
512 | else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) | |
513 | png_handle_tIME(png_ptr, info_ptr, length); | |
514 | #endif | |
515 | #if defined(PNG_READ_tRNS_SUPPORTED) | |
516 | else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) | |
517 | png_handle_tRNS(png_ptr, info_ptr, length); | |
518 | #endif | |
519 | #if defined(PNG_READ_zTXt_SUPPORTED) | |
520 | else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) | |
521 | png_handle_zTXt(png_ptr, info_ptr, length); | |
522 | #endif | |
523 | #if defined(PNG_READ_iTXt_SUPPORTED) | |
524 | else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) | |
525 | png_handle_iTXt(png_ptr, info_ptr, length); | |
526 | #endif | |
527 | else | |
528 | png_handle_unknown(png_ptr, info_ptr, length); | |
529 | } | |
530 | } | |
531 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
532 | ||
533 | /* optional call to update the users info_ptr structure */ | |
534 | void PNGAPI | |
535 | png_read_update_info(png_structp png_ptr, png_infop info_ptr) | |
536 | { | |
537 | png_debug(1, "in png_read_update_info\n"); | |
538 | if(png_ptr == NULL) return; | |
539 | if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) | |
540 | png_read_start_row(png_ptr); | |
541 | else | |
542 | png_warning(png_ptr, | |
543 | "Ignoring extra png_read_update_info() call; row buffer not reallocated"); | |
544 | png_read_transform_info(png_ptr, info_ptr); | |
545 | } | |
546 | ||
547 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
548 | /* Initialize palette, background, etc, after transformations | |
549 | * are set, but before any reading takes place. This allows | |
550 | * the user to obtain a gamma-corrected palette, for example. | |
551 | * If the user doesn't call this, we will do it ourselves. | |
552 | */ | |
553 | void PNGAPI | |
554 | png_start_read_image(png_structp png_ptr) | |
555 | { | |
556 | png_debug(1, "in png_start_read_image\n"); | |
557 | if(png_ptr == NULL) return; | |
558 | if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) | |
559 | png_read_start_row(png_ptr); | |
560 | } | |
561 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
562 | ||
563 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
564 | void PNGAPI | |
565 | png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) | |
566 | { | |
567 | #ifdef PNG_USE_LOCAL_ARRAYS | |
568 | PNG_CONST PNG_IDAT; | |
569 | PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, | |
570 | 0xff}; | |
571 | PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; | |
572 | #endif | |
573 | int ret; | |
574 | if(png_ptr == NULL) return; | |
575 | png_debug2(1, "in png_read_row (row %lu, pass %d)\n", | |
576 | png_ptr->row_number, png_ptr->pass); | |
577 | if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) | |
578 | png_read_start_row(png_ptr); | |
579 | if (png_ptr->row_number == 0 && png_ptr->pass == 0) | |
580 | { | |
581 | /* check for transforms that have been set but were defined out */ | |
582 | #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED) | |
583 | if (png_ptr->transformations & PNG_INVERT_MONO) | |
584 | png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined."); | |
585 | #endif | |
586 | #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED) | |
587 | if (png_ptr->transformations & PNG_FILLER) | |
588 | png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined."); | |
589 | #endif | |
590 | #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED) | |
591 | if (png_ptr->transformations & PNG_PACKSWAP) | |
592 | png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined."); | |
593 | #endif | |
594 | #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED) | |
595 | if (png_ptr->transformations & PNG_PACK) | |
596 | png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined."); | |
597 | #endif | |
598 | #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) | |
599 | if (png_ptr->transformations & PNG_SHIFT) | |
600 | png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined."); | |
601 | #endif | |
602 | #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED) | |
603 | if (png_ptr->transformations & PNG_BGR) | |
604 | png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined."); | |
605 | #endif | |
606 | #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED) | |
607 | if (png_ptr->transformations & PNG_SWAP_BYTES) | |
608 | png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined."); | |
609 | #endif | |
610 | } | |
611 | ||
612 | #if defined(PNG_READ_INTERLACING_SUPPORTED) | |
613 | /* if interlaced and we do not need a new row, combine row and return */ | |
614 | if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) | |
615 | { | |
616 | switch (png_ptr->pass) | |
617 | { | |
618 | case 0: | |
619 | if (png_ptr->row_number & 0x07) | |
620 | { | |
621 | if (dsp_row != NULL) | |
622 | png_combine_row(png_ptr, dsp_row, | |
623 | png_pass_dsp_mask[png_ptr->pass]); | |
624 | png_read_finish_row(png_ptr); | |
625 | return; | |
626 | } | |
627 | break; | |
628 | case 1: | |
629 | if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) | |
630 | { | |
631 | if (dsp_row != NULL) | |
632 | png_combine_row(png_ptr, dsp_row, | |
633 | png_pass_dsp_mask[png_ptr->pass]); | |
634 | png_read_finish_row(png_ptr); | |
635 | return; | |
636 | } | |
637 | break; | |
638 | case 2: | |
639 | if ((png_ptr->row_number & 0x07) != 4) | |
640 | { | |
641 | if (dsp_row != NULL && (png_ptr->row_number & 4)) | |
642 | png_combine_row(png_ptr, dsp_row, | |
643 | png_pass_dsp_mask[png_ptr->pass]); | |
644 | png_read_finish_row(png_ptr); | |
645 | return; | |
646 | } | |
647 | break; | |
648 | case 3: | |
649 | if ((png_ptr->row_number & 3) || png_ptr->width < 3) | |
650 | { | |
651 | if (dsp_row != NULL) | |
652 | png_combine_row(png_ptr, dsp_row, | |
653 | png_pass_dsp_mask[png_ptr->pass]); | |
654 | png_read_finish_row(png_ptr); | |
655 | return; | |
656 | } | |
657 | break; | |
658 | case 4: | |
659 | if ((png_ptr->row_number & 3) != 2) | |
660 | { | |
661 | if (dsp_row != NULL && (png_ptr->row_number & 2)) | |
662 | png_combine_row(png_ptr, dsp_row, | |
663 | png_pass_dsp_mask[png_ptr->pass]); | |
664 | png_read_finish_row(png_ptr); | |
665 | return; | |
666 | } | |
667 | break; | |
668 | case 5: | |
669 | if ((png_ptr->row_number & 1) || png_ptr->width < 2) | |
670 | { | |
671 | if (dsp_row != NULL) | |
672 | png_combine_row(png_ptr, dsp_row, | |
673 | png_pass_dsp_mask[png_ptr->pass]); | |
674 | png_read_finish_row(png_ptr); | |
675 | return; | |
676 | } | |
677 | break; | |
678 | case 6: | |
679 | if (!(png_ptr->row_number & 1)) | |
680 | { | |
681 | png_read_finish_row(png_ptr); | |
682 | return; | |
683 | } | |
684 | break; | |
685 | } | |
686 | } | |
687 | #endif | |
688 | ||
689 | if (!(png_ptr->mode & PNG_HAVE_IDAT)) | |
690 | png_error(png_ptr, "Invalid attempt to read row data"); | |
691 | ||
692 | png_ptr->zstream.next_out = png_ptr->row_buf; | |
693 | png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; | |
694 | do | |
695 | { | |
696 | if (!(png_ptr->zstream.avail_in)) | |
697 | { | |
698 | while (!png_ptr->idat_size) | |
699 | { | |
700 | png_byte chunk_length[4]; | |
701 | ||
702 | png_crc_finish(png_ptr, 0); | |
703 | ||
704 | png_read_data(png_ptr, chunk_length, 4); | |
705 | png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length); | |
706 | ||
707 | png_reset_crc(png_ptr); | |
708 | png_crc_read(png_ptr, png_ptr->chunk_name, 4); | |
709 | if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) | |
710 | png_error(png_ptr, "Not enough image data"); | |
711 | } | |
712 | png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; | |
713 | png_ptr->zstream.next_in = png_ptr->zbuf; | |
714 | if (png_ptr->zbuf_size > png_ptr->idat_size) | |
715 | png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; | |
716 | png_crc_read(png_ptr, png_ptr->zbuf, | |
717 | (png_size_t)png_ptr->zstream.avail_in); | |
718 | png_ptr->idat_size -= png_ptr->zstream.avail_in; | |
719 | } | |
720 | ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); | |
721 | if (ret == Z_STREAM_END) | |
722 | { | |
723 | if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || | |
724 | png_ptr->idat_size) | |
725 | png_error(png_ptr, "Extra compressed data"); | |
726 | png_ptr->mode |= PNG_AFTER_IDAT; | |
727 | png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; | |
728 | break; | |
729 | } | |
730 | if (ret != Z_OK) | |
731 | png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : | |
732 | "Decompression error"); | |
733 | ||
734 | } while (png_ptr->zstream.avail_out); | |
735 | ||
736 | png_ptr->row_info.color_type = png_ptr->color_type; | |
737 | png_ptr->row_info.width = png_ptr->iwidth; | |
738 | png_ptr->row_info.channels = png_ptr->channels; | |
739 | png_ptr->row_info.bit_depth = png_ptr->bit_depth; | |
740 | png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; | |
741 | png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, | |
742 | png_ptr->row_info.width); | |
743 | ||
744 | if(png_ptr->row_buf[0]) | |
745 | png_read_filter_row(png_ptr, &(png_ptr->row_info), | |
746 | png_ptr->row_buf + 1, png_ptr->prev_row + 1, | |
747 | (int)(png_ptr->row_buf[0])); | |
748 | ||
749 | png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf, | |
750 | png_ptr->rowbytes + 1); | |
751 | ||
752 | #if defined(PNG_MNG_FEATURES_SUPPORTED) | |
753 | if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && | |
754 | (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) | |
755 | { | |
756 | /* Intrapixel differencing */ | |
757 | png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); | |
758 | } | |
759 | #endif | |
760 | ||
761 | ||
762 | if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) | |
763 | png_do_read_transformations(png_ptr); | |
764 | ||
765 | #if defined(PNG_READ_INTERLACING_SUPPORTED) | |
766 | /* blow up interlaced rows to full size */ | |
767 | if (png_ptr->interlaced && | |
768 | (png_ptr->transformations & PNG_INTERLACE)) | |
769 | { | |
770 | if (png_ptr->pass < 6) | |
771 | /* old interface (pre-1.0.9): | |
772 | png_do_read_interlace(&(png_ptr->row_info), | |
773 | png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); | |
774 | */ | |
775 | png_do_read_interlace(png_ptr); | |
776 | ||
777 | if (dsp_row != NULL) | |
778 | png_combine_row(png_ptr, dsp_row, | |
779 | png_pass_dsp_mask[png_ptr->pass]); | |
780 | if (row != NULL) | |
781 | png_combine_row(png_ptr, row, | |
782 | png_pass_mask[png_ptr->pass]); | |
783 | } | |
784 | else | |
785 | #endif | |
786 | { | |
787 | if (row != NULL) | |
788 | png_combine_row(png_ptr, row, 0xff); | |
789 | if (dsp_row != NULL) | |
790 | png_combine_row(png_ptr, dsp_row, 0xff); | |
791 | } | |
792 | png_read_finish_row(png_ptr); | |
793 | ||
794 | if (png_ptr->read_row_fn != NULL) | |
795 | (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); | |
796 | } | |
797 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
798 | ||
799 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
800 | /* Read one or more rows of image data. If the image is interlaced, | |
801 | * and png_set_interlace_handling() has been called, the rows need to | |
802 | * contain the contents of the rows from the previous pass. If the | |
803 | * image has alpha or transparency, and png_handle_alpha()[*] has been | |
804 | * called, the rows contents must be initialized to the contents of the | |
805 | * screen. | |
806 | * | |
807 | * "row" holds the actual image, and pixels are placed in it | |
808 | * as they arrive. If the image is displayed after each pass, it will | |
809 | * appear to "sparkle" in. "display_row" can be used to display a | |
810 | * "chunky" progressive image, with finer detail added as it becomes | |
811 | * available. If you do not want this "chunky" display, you may pass | |
812 | * NULL for display_row. If you do not want the sparkle display, and | |
813 | * you have not called png_handle_alpha(), you may pass NULL for rows. | |
814 | * If you have called png_handle_alpha(), and the image has either an | |
815 | * alpha channel or a transparency chunk, you must provide a buffer for | |
816 | * rows. In this case, you do not have to provide a display_row buffer | |
817 | * also, but you may. If the image is not interlaced, or if you have | |
818 | * not called png_set_interlace_handling(), the display_row buffer will | |
819 | * be ignored, so pass NULL to it. | |
820 | * | |
821 | * [*] png_handle_alpha() does not exist yet, as of this version of libpng | |
822 | */ | |
823 | ||
824 | void PNGAPI | |
825 | png_read_rows(png_structp png_ptr, png_bytepp row, | |
826 | png_bytepp display_row, png_uint_32 num_rows) | |
827 | { | |
828 | png_uint_32 i; | |
829 | png_bytepp rp; | |
830 | png_bytepp dp; | |
831 | ||
832 | png_debug(1, "in png_read_rows\n"); | |
833 | if(png_ptr == NULL) return; | |
834 | rp = row; | |
835 | dp = display_row; | |
836 | if (rp != NULL && dp != NULL) | |
837 | for (i = 0; i < num_rows; i++) | |
838 | { | |
839 | png_bytep rptr = *rp++; | |
840 | png_bytep dptr = *dp++; | |
841 | ||
842 | png_read_row(png_ptr, rptr, dptr); | |
843 | } | |
844 | else if(rp != NULL) | |
845 | for (i = 0; i < num_rows; i++) | |
846 | { | |
847 | png_bytep rptr = *rp; | |
848 | png_read_row(png_ptr, rptr, png_bytep_NULL); | |
849 | rp++; | |
850 | } | |
851 | else if(dp != NULL) | |
852 | for (i = 0; i < num_rows; i++) | |
853 | { | |
854 | png_bytep dptr = *dp; | |
855 | png_read_row(png_ptr, png_bytep_NULL, dptr); | |
856 | dp++; | |
857 | } | |
858 | } | |
859 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
860 | ||
861 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
862 | /* Read the entire image. If the image has an alpha channel or a tRNS | |
863 | * chunk, and you have called png_handle_alpha()[*], you will need to | |
864 | * initialize the image to the current image that PNG will be overlaying. | |
865 | * We set the num_rows again here, in case it was incorrectly set in | |
866 | * png_read_start_row() by a call to png_read_update_info() or | |
867 | * png_start_read_image() if png_set_interlace_handling() wasn't called | |
868 | * prior to either of these functions like it should have been. You can | |
869 | * only call this function once. If you desire to have an image for | |
870 | * each pass of a interlaced image, use png_read_rows() instead. | |
871 | * | |
872 | * [*] png_handle_alpha() does not exist yet, as of this version of libpng | |
873 | */ | |
874 | void PNGAPI | |
875 | png_read_image(png_structp png_ptr, png_bytepp image) | |
876 | { | |
877 | png_uint_32 i,image_height; | |
878 | int pass, j; | |
879 | png_bytepp rp; | |
880 | ||
881 | png_debug(1, "in png_read_image\n"); | |
882 | if(png_ptr == NULL) return; | |
883 | ||
884 | #ifdef PNG_READ_INTERLACING_SUPPORTED | |
885 | pass = png_set_interlace_handling(png_ptr); | |
886 | #else | |
887 | if (png_ptr->interlaced) | |
888 | png_error(png_ptr, | |
889 | "Cannot read interlaced image -- interlace handler disabled."); | |
890 | pass = 1; | |
891 | #endif | |
892 | ||
893 | ||
894 | image_height=png_ptr->height; | |
895 | png_ptr->num_rows = image_height; /* Make sure this is set correctly */ | |
896 | ||
897 | for (j = 0; j < pass; j++) | |
898 | { | |
899 | rp = image; | |
900 | for (i = 0; i < image_height; i++) | |
901 | { | |
902 | png_read_row(png_ptr, *rp, png_bytep_NULL); | |
903 | rp++; | |
904 | } | |
905 | } | |
906 | } | |
907 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
908 | ||
909 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
910 | /* Read the end of the PNG file. Will not read past the end of the | |
911 | * file, will verify the end is accurate, and will read any comments | |
912 | * or time information at the end of the file, if info is not NULL. | |
913 | */ | |
914 | void PNGAPI | |
915 | png_read_end(png_structp png_ptr, png_infop info_ptr) | |
916 | { | |
917 | png_byte chunk_length[4]; | |
918 | png_uint_32 length; | |
919 | ||
920 | png_debug(1, "in png_read_end\n"); | |
921 | if(png_ptr == NULL) return; | |
922 | png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ | |
923 | ||
924 | do | |
925 | { | |
926 | #ifdef PNG_USE_LOCAL_ARRAYS | |
927 | PNG_CONST PNG_IHDR; | |
928 | PNG_CONST PNG_IDAT; | |
929 | PNG_CONST PNG_IEND; | |
930 | PNG_CONST PNG_PLTE; | |
931 | #if defined(PNG_READ_bKGD_SUPPORTED) | |
932 | PNG_CONST PNG_bKGD; | |
933 | #endif | |
934 | #if defined(PNG_READ_cHRM_SUPPORTED) | |
935 | PNG_CONST PNG_cHRM; | |
936 | #endif | |
937 | #if defined(PNG_READ_gAMA_SUPPORTED) | |
938 | PNG_CONST PNG_gAMA; | |
939 | #endif | |
940 | #if defined(PNG_READ_hIST_SUPPORTED) | |
941 | PNG_CONST PNG_hIST; | |
942 | #endif | |
943 | #if defined(PNG_READ_iCCP_SUPPORTED) | |
944 | PNG_CONST PNG_iCCP; | |
945 | #endif | |
946 | #if defined(PNG_READ_iTXt_SUPPORTED) | |
947 | PNG_CONST PNG_iTXt; | |
948 | #endif | |
949 | #if defined(PNG_READ_oFFs_SUPPORTED) | |
950 | PNG_CONST PNG_oFFs; | |
951 | #endif | |
952 | #if defined(PNG_READ_pCAL_SUPPORTED) | |
953 | PNG_CONST PNG_pCAL; | |
954 | #endif | |
955 | #if defined(PNG_READ_pHYs_SUPPORTED) | |
956 | PNG_CONST PNG_pHYs; | |
957 | #endif | |
958 | #if defined(PNG_READ_sBIT_SUPPORTED) | |
959 | PNG_CONST PNG_sBIT; | |
960 | #endif | |
961 | #if defined(PNG_READ_sCAL_SUPPORTED) | |
962 | PNG_CONST PNG_sCAL; | |
963 | #endif | |
964 | #if defined(PNG_READ_sPLT_SUPPORTED) | |
965 | PNG_CONST PNG_sPLT; | |
966 | #endif | |
967 | #if defined(PNG_READ_sRGB_SUPPORTED) | |
968 | PNG_CONST PNG_sRGB; | |
969 | #endif | |
970 | #if defined(PNG_READ_tEXt_SUPPORTED) | |
971 | PNG_CONST PNG_tEXt; | |
972 | #endif | |
973 | #if defined(PNG_READ_tIME_SUPPORTED) | |
974 | PNG_CONST PNG_tIME; | |
975 | #endif | |
976 | #if defined(PNG_READ_tRNS_SUPPORTED) | |
977 | PNG_CONST PNG_tRNS; | |
978 | #endif | |
979 | #if defined(PNG_READ_zTXt_SUPPORTED) | |
980 | PNG_CONST PNG_zTXt; | |
981 | #endif | |
982 | #endif /* PNG_USE_LOCAL_ARRAYS */ | |
983 | ||
984 | png_read_data(png_ptr, chunk_length, 4); | |
985 | length = png_get_uint_31(png_ptr,chunk_length); | |
986 | ||
987 | png_reset_crc(png_ptr); | |
988 | png_crc_read(png_ptr, png_ptr->chunk_name, 4); | |
989 | ||
990 | png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name); | |
991 | ||
992 | if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) | |
993 | png_handle_IHDR(png_ptr, info_ptr, length); | |
994 | else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) | |
995 | png_handle_IEND(png_ptr, info_ptr, length); | |
996 | #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED | |
997 | else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) | |
998 | { | |
999 | if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) | |
1000 | { | |
1001 | if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) | |
1002 | png_error(png_ptr, "Too many IDAT's found"); | |
1003 | } | |
1004 | png_handle_unknown(png_ptr, info_ptr, length); | |
1005 | if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) | |
1006 | png_ptr->mode |= PNG_HAVE_PLTE; | |
1007 | } | |
1008 | #endif | |
1009 | else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) | |
1010 | { | |
1011 | /* Zero length IDATs are legal after the last IDAT has been | |
1012 | * read, but not after other chunks have been read. | |
1013 | */ | |
1014 | if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) | |
1015 | png_error(png_ptr, "Too many IDAT's found"); | |
1016 | png_crc_finish(png_ptr, length); | |
1017 | } | |
1018 | else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) | |
1019 | png_handle_PLTE(png_ptr, info_ptr, length); | |
1020 | #if defined(PNG_READ_bKGD_SUPPORTED) | |
1021 | else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4)) | |
1022 | png_handle_bKGD(png_ptr, info_ptr, length); | |
1023 | #endif | |
1024 | #if defined(PNG_READ_cHRM_SUPPORTED) | |
1025 | else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4)) | |
1026 | png_handle_cHRM(png_ptr, info_ptr, length); | |
1027 | #endif | |
1028 | #if defined(PNG_READ_gAMA_SUPPORTED) | |
1029 | else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) | |
1030 | png_handle_gAMA(png_ptr, info_ptr, length); | |
1031 | #endif | |
1032 | #if defined(PNG_READ_hIST_SUPPORTED) | |
1033 | else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4)) | |
1034 | png_handle_hIST(png_ptr, info_ptr, length); | |
1035 | #endif | |
1036 | #if defined(PNG_READ_oFFs_SUPPORTED) | |
1037 | else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4)) | |
1038 | png_handle_oFFs(png_ptr, info_ptr, length); | |
1039 | #endif | |
1040 | #if defined(PNG_READ_pCAL_SUPPORTED) | |
1041 | else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4)) | |
1042 | png_handle_pCAL(png_ptr, info_ptr, length); | |
1043 | #endif | |
1044 | #if defined(PNG_READ_sCAL_SUPPORTED) | |
1045 | else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) | |
1046 | png_handle_sCAL(png_ptr, info_ptr, length); | |
1047 | #endif | |
1048 | #if defined(PNG_READ_pHYs_SUPPORTED) | |
1049 | else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4)) | |
1050 | png_handle_pHYs(png_ptr, info_ptr, length); | |
1051 | #endif | |
1052 | #if defined(PNG_READ_sBIT_SUPPORTED) | |
1053 | else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4)) | |
1054 | png_handle_sBIT(png_ptr, info_ptr, length); | |
1055 | #endif | |
1056 | #if defined(PNG_READ_sRGB_SUPPORTED) | |
1057 | else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4)) | |
1058 | png_handle_sRGB(png_ptr, info_ptr, length); | |
1059 | #endif | |
1060 | #if defined(PNG_READ_iCCP_SUPPORTED) | |
1061 | else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) | |
1062 | png_handle_iCCP(png_ptr, info_ptr, length); | |
1063 | #endif | |
1064 | #if defined(PNG_READ_sPLT_SUPPORTED) | |
1065 | else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) | |
1066 | png_handle_sPLT(png_ptr, info_ptr, length); | |
1067 | #endif | |
1068 | #if defined(PNG_READ_tEXt_SUPPORTED) | |
1069 | else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) | |
1070 | png_handle_tEXt(png_ptr, info_ptr, length); | |
1071 | #endif | |
1072 | #if defined(PNG_READ_tIME_SUPPORTED) | |
1073 | else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) | |
1074 | png_handle_tIME(png_ptr, info_ptr, length); | |
1075 | #endif | |
1076 | #if defined(PNG_READ_tRNS_SUPPORTED) | |
1077 | else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) | |
1078 | png_handle_tRNS(png_ptr, info_ptr, length); | |
1079 | #endif | |
1080 | #if defined(PNG_READ_zTXt_SUPPORTED) | |
1081 | else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) | |
1082 | png_handle_zTXt(png_ptr, info_ptr, length); | |
1083 | #endif | |
1084 | #if defined(PNG_READ_iTXt_SUPPORTED) | |
1085 | else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) | |
1086 | png_handle_iTXt(png_ptr, info_ptr, length); | |
1087 | #endif | |
1088 | else | |
1089 | png_handle_unknown(png_ptr, info_ptr, length); | |
1090 | } while (!(png_ptr->mode & PNG_HAVE_IEND)); | |
1091 | } | |
1092 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
1093 | ||
1094 | /* free all memory used by the read */ | |
1095 | void PNGAPI | |
1096 | png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, | |
1097 | png_infopp end_info_ptr_ptr) | |
1098 | { | |
1099 | png_structp png_ptr = NULL; | |
1100 | png_infop info_ptr = NULL, end_info_ptr = NULL; | |
1101 | #ifdef PNG_USER_MEM_SUPPORTED | |
1102 | png_free_ptr free_fn; | |
1103 | png_voidp mem_ptr; | |
1104 | #endif | |
1105 | ||
1106 | png_debug(1, "in png_destroy_read_struct\n"); | |
1107 | if (png_ptr_ptr != NULL) | |
1108 | png_ptr = *png_ptr_ptr; | |
1109 | ||
1110 | if (info_ptr_ptr != NULL) | |
1111 | info_ptr = *info_ptr_ptr; | |
1112 | ||
1113 | if (end_info_ptr_ptr != NULL) | |
1114 | end_info_ptr = *end_info_ptr_ptr; | |
1115 | ||
1116 | #ifdef PNG_USER_MEM_SUPPORTED | |
1117 | free_fn = png_ptr->free_fn; | |
1118 | mem_ptr = png_ptr->mem_ptr; | |
1119 | #endif | |
1120 | ||
1121 | png_read_destroy(png_ptr, info_ptr, end_info_ptr); | |
1122 | ||
1123 | if (info_ptr != NULL) | |
1124 | { | |
1125 | #if defined(PNG_TEXT_SUPPORTED) | |
1126 | png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1); | |
1127 | #endif | |
1128 | ||
1129 | #ifdef PNG_USER_MEM_SUPPORTED | |
1130 | png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, | |
1131 | (png_voidp)mem_ptr); | |
1132 | #else | |
1133 | png_destroy_struct((png_voidp)info_ptr); | |
1134 | #endif | |
1135 | *info_ptr_ptr = NULL; | |
1136 | } | |
1137 | ||
1138 | if (end_info_ptr != NULL) | |
1139 | { | |
1140 | #if defined(PNG_READ_TEXT_SUPPORTED) | |
1141 | png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1); | |
1142 | #endif | |
1143 | #ifdef PNG_USER_MEM_SUPPORTED | |
1144 | png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn, | |
1145 | (png_voidp)mem_ptr); | |
1146 | #else | |
1147 | png_destroy_struct((png_voidp)end_info_ptr); | |
1148 | #endif | |
1149 | *end_info_ptr_ptr = NULL; | |
1150 | } | |
1151 | ||
1152 | if (png_ptr != NULL) | |
1153 | { | |
1154 | #ifdef PNG_USER_MEM_SUPPORTED | |
1155 | png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, | |
1156 | (png_voidp)mem_ptr); | |
1157 | #else | |
1158 | png_destroy_struct((png_voidp)png_ptr); | |
1159 | #endif | |
1160 | *png_ptr_ptr = NULL; | |
1161 | } | |
1162 | } | |
1163 | ||
1164 | /* free all memory used by the read (old method) */ | |
1165 | void /* PRIVATE */ | |
1166 | png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr) | |
1167 | { | |
1168 | #ifdef PNG_SETJMP_SUPPORTED | |
1169 | jmp_buf tmp_jmp; | |
1170 | #endif | |
1171 | png_error_ptr error_fn; | |
1172 | png_error_ptr warning_fn; | |
1173 | png_voidp error_ptr; | |
1174 | #ifdef PNG_USER_MEM_SUPPORTED | |
1175 | png_free_ptr free_fn; | |
1176 | #endif | |
1177 | ||
1178 | png_debug(1, "in png_read_destroy\n"); | |
1179 | if (info_ptr != NULL) | |
1180 | png_info_destroy(png_ptr, info_ptr); | |
1181 | ||
1182 | if (end_info_ptr != NULL) | |
1183 | png_info_destroy(png_ptr, end_info_ptr); | |
1184 | ||
1185 | png_free(png_ptr, png_ptr->zbuf); | |
1186 | png_free(png_ptr, png_ptr->big_row_buf); | |
1187 | png_free(png_ptr, png_ptr->prev_row); | |
1188 | #if defined(PNG_READ_DITHER_SUPPORTED) | |
1189 | png_free(png_ptr, png_ptr->palette_lookup); | |
1190 | png_free(png_ptr, png_ptr->dither_index); | |
1191 | #endif | |
1192 | #if defined(PNG_READ_GAMMA_SUPPORTED) | |
1193 | png_free(png_ptr, png_ptr->gamma_table); | |
1194 | #endif | |
1195 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) | |
1196 | png_free(png_ptr, png_ptr->gamma_from_1); | |
1197 | png_free(png_ptr, png_ptr->gamma_to_1); | |
1198 | #endif | |
1199 | #ifdef PNG_FREE_ME_SUPPORTED | |
1200 | if (png_ptr->free_me & PNG_FREE_PLTE) | |
1201 | png_zfree(png_ptr, png_ptr->palette); | |
1202 | png_ptr->free_me &= ~PNG_FREE_PLTE; | |
1203 | #else | |
1204 | if (png_ptr->flags & PNG_FLAG_FREE_PLTE) | |
1205 | png_zfree(png_ptr, png_ptr->palette); | |
1206 | png_ptr->flags &= ~PNG_FLAG_FREE_PLTE; | |
1207 | #endif | |
1208 | #if defined(PNG_tRNS_SUPPORTED) || \ | |
1209 | defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) | |
1210 | #ifdef PNG_FREE_ME_SUPPORTED | |
1211 | if (png_ptr->free_me & PNG_FREE_TRNS) | |
1212 | png_free(png_ptr, png_ptr->trans); | |
1213 | png_ptr->free_me &= ~PNG_FREE_TRNS; | |
1214 | #else | |
1215 | if (png_ptr->flags & PNG_FLAG_FREE_TRNS) | |
1216 | png_free(png_ptr, png_ptr->trans); | |
1217 | png_ptr->flags &= ~PNG_FLAG_FREE_TRNS; | |
1218 | #endif | |
1219 | #endif | |
1220 | #if defined(PNG_READ_hIST_SUPPORTED) | |
1221 | #ifdef PNG_FREE_ME_SUPPORTED | |
1222 | if (png_ptr->free_me & PNG_FREE_HIST) | |
1223 | png_free(png_ptr, png_ptr->hist); | |
1224 | png_ptr->free_me &= ~PNG_FREE_HIST; | |
1225 | #else | |
1226 | if (png_ptr->flags & PNG_FLAG_FREE_HIST) | |
1227 | png_free(png_ptr, png_ptr->hist); | |
1228 | png_ptr->flags &= ~PNG_FLAG_FREE_HIST; | |
1229 | #endif | |
1230 | #endif | |
1231 | #if defined(PNG_READ_GAMMA_SUPPORTED) | |
1232 | if (png_ptr->gamma_16_table != NULL) | |
1233 | { | |
1234 | int i; | |
1235 | int istop = (1 << (8 - png_ptr->gamma_shift)); | |
1236 | for (i = 0; i < istop; i++) | |
1237 | { | |
1238 | png_free(png_ptr, png_ptr->gamma_16_table[i]); | |
1239 | } | |
1240 | png_free(png_ptr, png_ptr->gamma_16_table); | |
1241 | } | |
1242 | #if defined(PNG_READ_BACKGROUND_SUPPORTED) | |
1243 | if (png_ptr->gamma_16_from_1 != NULL) | |
1244 | { | |
1245 | int i; | |
1246 | int istop = (1 << (8 - png_ptr->gamma_shift)); | |
1247 | for (i = 0; i < istop; i++) | |
1248 | { | |
1249 | png_free(png_ptr, png_ptr->gamma_16_from_1[i]); | |
1250 | } | |
1251 | png_free(png_ptr, png_ptr->gamma_16_from_1); | |
1252 | } | |
1253 | if (png_ptr->gamma_16_to_1 != NULL) | |
1254 | { | |
1255 | int i; | |
1256 | int istop = (1 << (8 - png_ptr->gamma_shift)); | |
1257 | for (i = 0; i < istop; i++) | |
1258 | { | |
1259 | png_free(png_ptr, png_ptr->gamma_16_to_1[i]); | |
1260 | } | |
1261 | png_free(png_ptr, png_ptr->gamma_16_to_1); | |
1262 | } | |
1263 | #endif | |
1264 | #endif | |
1265 | #if defined(PNG_TIME_RFC1123_SUPPORTED) | |
1266 | png_free(png_ptr, png_ptr->time_buffer); | |
1267 | #endif | |
1268 | ||
1269 | inflateEnd(&png_ptr->zstream); | |
1270 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED | |
1271 | png_free(png_ptr, png_ptr->save_buffer); | |
1272 | #endif | |
1273 | ||
1274 | #ifdef PNG_PROGRESSIVE_READ_SUPPORTED | |
1275 | #ifdef PNG_TEXT_SUPPORTED | |
1276 | png_free(png_ptr, png_ptr->current_text); | |
1277 | #endif /* PNG_TEXT_SUPPORTED */ | |
1278 | #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ | |
1279 | ||
1280 | /* Save the important info out of the png_struct, in case it is | |
1281 | * being used again. | |
1282 | */ | |
1283 | #ifdef PNG_SETJMP_SUPPORTED | |
1284 | png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf)); | |
1285 | #endif | |
1286 | ||
1287 | error_fn = png_ptr->error_fn; | |
1288 | warning_fn = png_ptr->warning_fn; | |
1289 | error_ptr = png_ptr->error_ptr; | |
1290 | #ifdef PNG_USER_MEM_SUPPORTED | |
1291 | free_fn = png_ptr->free_fn; | |
1292 | #endif | |
1293 | ||
1294 | png_memset(png_ptr, 0, png_sizeof (png_struct)); | |
1295 | ||
1296 | png_ptr->error_fn = error_fn; | |
1297 | png_ptr->warning_fn = warning_fn; | |
1298 | png_ptr->error_ptr = error_ptr; | |
1299 | #ifdef PNG_USER_MEM_SUPPORTED | |
1300 | png_ptr->free_fn = free_fn; | |
1301 | #endif | |
1302 | ||
1303 | #ifdef PNG_SETJMP_SUPPORTED | |
1304 | png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf)); | |
1305 | #endif | |
1306 | ||
1307 | } | |
1308 | ||
1309 | void PNGAPI | |
1310 | png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) | |
1311 | { | |
1312 | if(png_ptr == NULL) return; | |
1313 | png_ptr->read_row_fn = read_row_fn; | |
1314 | } | |
1315 | ||
1316 | ||
1317 | #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED | |
1318 | #if defined(PNG_INFO_IMAGE_SUPPORTED) | |
1319 | void PNGAPI | |
1320 | png_read_png(png_structp png_ptr, png_infop info_ptr, | |
1321 | int transforms, | |
1322 | voidp params) | |
1323 | { | |
1324 | int row; | |
1325 | ||
1326 | if(png_ptr == NULL) return; | |
1327 | #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) | |
1328 | /* invert the alpha channel from opacity to transparency | |
1329 | */ | |
1330 | if (transforms & PNG_TRANSFORM_INVERT_ALPHA) | |
1331 | png_set_invert_alpha(png_ptr); | |
1332 | #endif | |
1333 | ||
1334 | /* png_read_info() gives us all of the information from the | |
1335 | * PNG file before the first IDAT (image data chunk). | |
1336 | */ | |
1337 | png_read_info(png_ptr, info_ptr); | |
1338 | if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep)) | |
1339 | png_error(png_ptr,"Image is too high to process with png_read_png()"); | |
1340 | ||
1341 | /* -------------- image transformations start here ------------------- */ | |
1342 | ||
1343 | #if defined(PNG_READ_16_TO_8_SUPPORTED) | |
1344 | /* tell libpng to strip 16 bit/color files down to 8 bits per color | |
1345 | */ | |
1346 | if (transforms & PNG_TRANSFORM_STRIP_16) | |
1347 | png_set_strip_16(png_ptr); | |
1348 | #endif | |
1349 | ||
1350 | #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) | |
1351 | /* Strip alpha bytes from the input data without combining with | |
1352 | * the background (not recommended). | |
1353 | */ | |
1354 | if (transforms & PNG_TRANSFORM_STRIP_ALPHA) | |
1355 | png_set_strip_alpha(png_ptr); | |
1356 | #endif | |
1357 | ||
1358 | #if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED) | |
1359 | /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single | |
1360 | * byte into separate bytes (useful for paletted and grayscale images). | |
1361 | */ | |
1362 | if (transforms & PNG_TRANSFORM_PACKING) | |
1363 | png_set_packing(png_ptr); | |
1364 | #endif | |
1365 | ||
1366 | #if defined(PNG_READ_PACKSWAP_SUPPORTED) | |
1367 | /* Change the order of packed pixels to least significant bit first | |
1368 | * (not useful if you are using png_set_packing). | |
1369 | */ | |
1370 | if (transforms & PNG_TRANSFORM_PACKSWAP) | |
1371 | png_set_packswap(png_ptr); | |
1372 | #endif | |
1373 | ||
1374 | #if defined(PNG_READ_EXPAND_SUPPORTED) | |
1375 | /* Expand paletted colors into true RGB triplets | |
1376 | * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel | |
1377 | * Expand paletted or RGB images with transparency to full alpha | |
1378 | * channels so the data will be available as RGBA quartets. | |
1379 | */ | |
1380 | if (transforms & PNG_TRANSFORM_EXPAND) | |
1381 | if ((png_ptr->bit_depth < 8) || | |
1382 | (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) || | |
1383 | (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))) | |
1384 | png_set_expand(png_ptr); | |
1385 | #endif | |
1386 | ||
1387 | /* We don't handle background color or gamma transformation or dithering. | |
1388 | */ | |
1389 | ||
1390 | #if defined(PNG_READ_INVERT_SUPPORTED) | |
1391 | /* invert monochrome files to have 0 as white and 1 as black | |
1392 | */ | |
1393 | if (transforms & PNG_TRANSFORM_INVERT_MONO) | |
1394 | png_set_invert_mono(png_ptr); | |
1395 | #endif | |
1396 | ||
1397 | #if defined(PNG_READ_SHIFT_SUPPORTED) | |
1398 | /* If you want to shift the pixel values from the range [0,255] or | |
1399 | * [0,65535] to the original [0,7] or [0,31], or whatever range the | |
1400 | * colors were originally in: | |
1401 | */ | |
1402 | if ((transforms & PNG_TRANSFORM_SHIFT) | |
1403 | && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) | |
1404 | { | |
1405 | png_color_8p sig_bit; | |
1406 | ||
1407 | png_get_sBIT(png_ptr, info_ptr, &sig_bit); | |
1408 | png_set_shift(png_ptr, sig_bit); | |
1409 | } | |
1410 | #endif | |
1411 | ||
1412 | #if defined(PNG_READ_BGR_SUPPORTED) | |
1413 | /* flip the RGB pixels to BGR (or RGBA to BGRA) | |
1414 | */ | |
1415 | if (transforms & PNG_TRANSFORM_BGR) | |
1416 | png_set_bgr(png_ptr); | |
1417 | #endif | |
1418 | ||
1419 | #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) | |
1420 | /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) | |
1421 | */ | |
1422 | if (transforms & PNG_TRANSFORM_SWAP_ALPHA) | |
1423 | png_set_swap_alpha(png_ptr); | |
1424 | #endif | |
1425 | ||
1426 | #if defined(PNG_READ_SWAP_SUPPORTED) | |
1427 | /* swap bytes of 16 bit files to least significant byte first | |
1428 | */ | |
1429 | if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) | |
1430 | png_set_swap(png_ptr); | |
1431 | #endif | |
1432 | ||
1433 | /* We don't handle adding filler bytes */ | |
1434 | ||
1435 | /* Optional call to gamma correct and add the background to the palette | |
1436 | * and update info structure. REQUIRED if you are expecting libpng to | |
1437 | * update the palette for you (i.e., you selected such a transform above). | |
1438 | */ | |
1439 | png_read_update_info(png_ptr, info_ptr); | |
1440 | ||
1441 | /* -------------- image transformations end here ------------------- */ | |
1442 | ||
1443 | #ifdef PNG_FREE_ME_SUPPORTED | |
1444 | png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); | |
1445 | #endif | |
1446 | if(info_ptr->row_pointers == NULL) | |
1447 | { | |
1448 | info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr, | |
1449 | info_ptr->height * png_sizeof(png_bytep)); | |
1450 | #ifdef PNG_FREE_ME_SUPPORTED | |
1451 | info_ptr->free_me |= PNG_FREE_ROWS; | |
1452 | #endif | |
1453 | for (row = 0; row < (int)info_ptr->height; row++) | |
1454 | { | |
1455 | info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr, | |
1456 | png_get_rowbytes(png_ptr, info_ptr)); | |
1457 | } | |
1458 | } | |
1459 | ||
1460 | png_read_image(png_ptr, info_ptr->row_pointers); | |
1461 | info_ptr->valid |= PNG_INFO_IDAT; | |
1462 | ||
1463 | /* read rest of file, and get additional chunks in info_ptr - REQUIRED */ | |
1464 | png_read_end(png_ptr, info_ptr); | |
1465 | ||
1466 | transforms = transforms; /* quiet compiler warnings */ | |
1467 | params = params; | |
1468 | ||
1469 | } | |
1470 | #endif /* PNG_INFO_IMAGE_SUPPORTED */ | |
1471 | #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ | |
1472 | #endif /* PNG_READ_SUPPORTED */ |