|
1 |
|
2 /* pngread.c - read a PNG file |
|
3 * |
|
4 * Last changed in libpng 1.2.30 [August 15, 2008] |
|
5 * For conditions of distribution and use, see copyright notice in png.h |
|
6 * Copyright (c) 1998-2008 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 #if defined(PNG_READ_SUPPORTED) |
|
17 |
|
18 /* Create a PNG structure for reading, and allocate any memory needed. */ |
|
19 png_structp PNGAPI |
|
20 png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr, |
|
21 png_error_ptr error_fn, png_error_ptr warn_fn) |
|
22 { |
|
23 |
|
24 #ifdef PNG_USER_MEM_SUPPORTED |
|
25 return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn, |
|
26 warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL)); |
|
27 } |
|
28 |
|
29 /* Alternate create PNG structure for reading, and allocate any memory needed. */ |
|
30 png_structp PNGAPI |
|
31 png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr, |
|
32 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, |
|
33 png_malloc_ptr malloc_fn, png_free_ptr free_fn) |
|
34 { |
|
35 #endif /* PNG_USER_MEM_SUPPORTED */ |
|
36 |
|
37 #ifdef PNG_SETJMP_SUPPORTED |
|
38 volatile |
|
39 #endif |
|
40 png_structp png_ptr; |
|
41 |
|
42 #ifdef PNG_SETJMP_SUPPORTED |
|
43 #ifdef USE_FAR_KEYWORD |
|
44 jmp_buf jmpbuf; |
|
45 #endif |
|
46 #endif |
|
47 |
|
48 int i; |
|
49 |
|
50 png_debug(1, "in png_create_read_struct\n"); |
|
51 #ifdef PNG_USER_MEM_SUPPORTED |
|
52 png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, |
|
53 (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr); |
|
54 #else |
|
55 png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); |
|
56 #endif |
|
57 if (png_ptr == NULL) |
|
58 return (NULL); |
|
59 |
|
60 /* added at libpng-1.2.6 */ |
|
61 #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
|
62 png_ptr->user_width_max=PNG_USER_WIDTH_MAX; |
|
63 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; |
|
64 #endif |
|
65 |
|
66 #ifdef PNG_SETJMP_SUPPORTED |
|
67 #ifdef USE_FAR_KEYWORD |
|
68 if (setjmp(jmpbuf)) |
|
69 #else |
|
70 if (setjmp(png_ptr->jmpbuf)) |
|
71 #endif |
|
72 { |
|
73 png_free(png_ptr, png_ptr->zbuf); |
|
74 png_ptr->zbuf = NULL; |
|
75 #ifdef PNG_USER_MEM_SUPPORTED |
|
76 png_destroy_struct_2((png_voidp)png_ptr, |
|
77 (png_free_ptr)free_fn, (png_voidp)mem_ptr); |
|
78 #else |
|
79 png_destroy_struct((png_voidp)png_ptr); |
|
80 #endif |
|
81 return (NULL); |
|
82 } |
|
83 #ifdef USE_FAR_KEYWORD |
|
84 png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf)); |
|
85 #endif |
|
86 #endif |
|
87 |
|
88 #ifdef PNG_USER_MEM_SUPPORTED |
|
89 png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); |
|
90 #endif |
|
91 |
|
92 png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); |
|
93 |
|
94 if (user_png_ver) |
|
95 { |
|
96 i = 0; |
|
97 do |
|
98 { |
|
99 if (user_png_ver[i] != png_libpng_ver[i]) |
|
100 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
|
101 } while (png_libpng_ver[i++]); |
|
102 } |
|
103 else |
|
104 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
|
105 |
|
106 |
|
107 if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) |
|
108 { |
|
109 /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so |
|
110 * we must recompile any applications that use any older library version. |
|
111 * For versions after libpng 1.0, we will be compatible, so we need |
|
112 * only check the first digit. |
|
113 */ |
|
114 if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || |
|
115 (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || |
|
116 (user_png_ver[0] == '0' && user_png_ver[2] < '9')) |
|
117 { |
|
118 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
|
119 char msg[80]; |
|
120 if (user_png_ver) |
|
121 { |
|
122 png_snprintf(msg, 80, |
|
123 "Application was compiled with png.h from libpng-%.20s", |
|
124 user_png_ver); |
|
125 png_warning(png_ptr, msg); |
|
126 } |
|
127 png_snprintf(msg, 80, |
|
128 "Application is running with png.c from libpng-%.20s", |
|
129 png_libpng_ver); |
|
130 png_warning(png_ptr, msg); |
|
131 #endif |
|
132 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
|
133 png_ptr->flags = 0; |
|
134 #endif |
|
135 png_error(png_ptr, |
|
136 "Incompatible libpng version in application and library"); |
|
137 } |
|
138 } |
|
139 |
|
140 /* initialize zbuf - compression buffer */ |
|
141 png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
|
142 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
|
143 (png_uint_32)png_ptr->zbuf_size); |
|
144 png_ptr->zstream.zalloc = png_zalloc; |
|
145 png_ptr->zstream.zfree = png_zfree; |
|
146 png_ptr->zstream.opaque = (voidpf)png_ptr; |
|
147 |
|
148 switch (inflateInit(&png_ptr->zstream)) |
|
149 { |
|
150 case Z_OK: /* Do nothing */ break; |
|
151 case Z_MEM_ERROR: |
|
152 case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break; |
|
153 case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break; |
|
154 default: png_error(png_ptr, "Unknown zlib error"); |
|
155 } |
|
156 |
|
157 png_ptr->zstream.next_out = png_ptr->zbuf; |
|
158 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
|
159 |
|
160 png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); |
|
161 |
|
162 #ifdef PNG_SETJMP_SUPPORTED |
|
163 /* Applications that neglect to set up their own setjmp() and then encounter |
|
164 a png_error() will longjmp here. Since the jmpbuf is then meaningless we |
|
165 abort instead of returning. */ |
|
166 #ifdef USE_FAR_KEYWORD |
|
167 if (setjmp(jmpbuf)) |
|
168 PNG_ABORT(); |
|
169 png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf)); |
|
170 #else |
|
171 if (setjmp(png_ptr->jmpbuf)) |
|
172 PNG_ABORT(); |
|
173 #endif |
|
174 #endif |
|
175 return (png_ptr); |
|
176 } |
|
177 |
|
178 #if defined(PNG_1_0_X) || defined(PNG_1_2_X) |
|
179 /* Initialize PNG structure for reading, and allocate any memory needed. |
|
180 This interface is deprecated in favour of the png_create_read_struct(), |
|
181 and it will disappear as of libpng-1.3.0. */ |
|
182 #undef png_read_init |
|
183 void PNGAPI |
|
184 png_read_init(png_structp png_ptr) |
|
185 { |
|
186 /* We only come here via pre-1.0.7-compiled applications */ |
|
187 png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0); |
|
188 } |
|
189 |
|
190 void PNGAPI |
|
191 png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver, |
|
192 png_size_t png_struct_size, png_size_t png_info_size) |
|
193 { |
|
194 /* We only come here via pre-1.0.12-compiled applications */ |
|
195 if (png_ptr == NULL) return; |
|
196 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
|
197 if (png_sizeof(png_struct) > png_struct_size || |
|
198 png_sizeof(png_info) > png_info_size) |
|
199 { |
|
200 char msg[80]; |
|
201 png_ptr->warning_fn = NULL; |
|
202 if (user_png_ver) |
|
203 { |
|
204 png_snprintf(msg, 80, |
|
205 "Application was compiled with png.h from libpng-%.20s", |
|
206 user_png_ver); |
|
207 png_warning(png_ptr, msg); |
|
208 } |
|
209 png_snprintf(msg, 80, |
|
210 "Application is running with png.c from libpng-%.20s", |
|
211 png_libpng_ver); |
|
212 png_warning(png_ptr, msg); |
|
213 } |
|
214 #endif |
|
215 if (png_sizeof(png_struct) > png_struct_size) |
|
216 { |
|
217 png_ptr->error_fn = NULL; |
|
218 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
|
219 png_ptr->flags = 0; |
|
220 #endif |
|
221 png_error(png_ptr, |
|
222 "The png struct allocated by the application for reading is too small."); |
|
223 } |
|
224 if (png_sizeof(png_info) > png_info_size) |
|
225 { |
|
226 png_ptr->error_fn = NULL; |
|
227 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
|
228 png_ptr->flags = 0; |
|
229 #endif |
|
230 png_error(png_ptr, |
|
231 "The info struct allocated by application for reading is too small."); |
|
232 } |
|
233 png_read_init_3(&png_ptr, user_png_ver, png_struct_size); |
|
234 } |
|
235 #endif /* PNG_1_0_X || PNG_1_2_X */ |
|
236 |
|
237 void PNGAPI |
|
238 png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver, |
|
239 png_size_t png_struct_size) |
|
240 { |
|
241 #ifdef PNG_SETJMP_SUPPORTED |
|
242 jmp_buf tmp_jmp; /* to save current jump buffer */ |
|
243 #endif |
|
244 |
|
245 int i = 0; |
|
246 |
|
247 png_structp png_ptr=*ptr_ptr; |
|
248 |
|
249 if (png_ptr == NULL) return; |
|
250 |
|
251 do |
|
252 { |
|
253 if (user_png_ver[i] != png_libpng_ver[i]) |
|
254 { |
|
255 #ifdef PNG_LEGACY_SUPPORTED |
|
256 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
|
257 #else |
|
258 png_ptr->warning_fn = NULL; |
|
259 png_warning(png_ptr, |
|
260 "Application uses deprecated png_read_init() and should be recompiled."); |
|
261 break; |
|
262 #endif |
|
263 } |
|
264 } while (png_libpng_ver[i++]); |
|
265 |
|
266 png_debug(1, "in png_read_init_3\n"); |
|
267 |
|
268 #ifdef PNG_SETJMP_SUPPORTED |
|
269 /* save jump buffer and error functions */ |
|
270 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf)); |
|
271 #endif |
|
272 |
|
273 if (png_sizeof(png_struct) > png_struct_size) |
|
274 { |
|
275 png_destroy_struct(png_ptr); |
|
276 *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); |
|
277 png_ptr = *ptr_ptr; |
|
278 } |
|
279 |
|
280 /* reset all variables to 0 */ |
|
281 png_memset(png_ptr, 0, png_sizeof(png_struct)); |
|
282 |
|
283 #ifdef PNG_SETJMP_SUPPORTED |
|
284 /* restore jump buffer */ |
|
285 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); |
|
286 #endif |
|
287 |
|
288 /* added at libpng-1.2.6 */ |
|
289 #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
|
290 png_ptr->user_width_max=PNG_USER_WIDTH_MAX; |
|
291 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; |
|
292 #endif |
|
293 |
|
294 /* initialize zbuf - compression buffer */ |
|
295 png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
|
296 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
|
297 (png_uint_32)png_ptr->zbuf_size); |
|
298 png_ptr->zstream.zalloc = png_zalloc; |
|
299 png_ptr->zstream.zfree = png_zfree; |
|
300 png_ptr->zstream.opaque = (voidpf)png_ptr; |
|
301 |
|
302 switch (inflateInit(&png_ptr->zstream)) |
|
303 { |
|
304 case Z_OK: /* Do nothing */ break; |
|
305 case Z_MEM_ERROR: |
|
306 case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break; |
|
307 case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break; |
|
308 default: png_error(png_ptr, "Unknown zlib error"); |
|
309 } |
|
310 |
|
311 png_ptr->zstream.next_out = png_ptr->zbuf; |
|
312 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
|
313 |
|
314 png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); |
|
315 } |
|
316 |
|
317 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
318 /* Read the information before the actual image data. This has been |
|
319 * changed in v0.90 to allow reading a file that already has the magic |
|
320 * bytes read from the stream. You can tell libpng how many bytes have |
|
321 * been read from the beginning of the stream (up to the maximum of 8) |
|
322 * via png_set_sig_bytes(), and we will only check the remaining bytes |
|
323 * here. The application can then have access to the signature bytes we |
|
324 * read if it is determined that this isn't a valid PNG file. |
|
325 */ |
|
326 void PNGAPI |
|
327 png_read_info(png_structp png_ptr, png_infop info_ptr) |
|
328 { |
|
329 if (png_ptr == NULL || info_ptr == NULL) return; |
|
330 png_debug(1, "in png_read_info\n"); |
|
331 /* If we haven't checked all of the PNG signature bytes, do so now. */ |
|
332 if (png_ptr->sig_bytes < 8) |
|
333 { |
|
334 png_size_t num_checked = png_ptr->sig_bytes, |
|
335 num_to_check = 8 - num_checked; |
|
336 |
|
337 png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); |
|
338 png_ptr->sig_bytes = 8; |
|
339 |
|
340 if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) |
|
341 { |
|
342 if (num_checked < 4 && |
|
343 png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) |
|
344 png_error(png_ptr, "Not a PNG file"); |
|
345 else |
|
346 png_error(png_ptr, "PNG file corrupted by ASCII conversion"); |
|
347 } |
|
348 if (num_checked < 3) |
|
349 png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; |
|
350 } |
|
351 |
|
352 for (;;) |
|
353 { |
|
354 #ifdef PNG_USE_LOCAL_ARRAYS |
|
355 PNG_CONST PNG_IHDR; |
|
356 PNG_CONST PNG_IDAT; |
|
357 PNG_CONST PNG_IEND; |
|
358 PNG_CONST PNG_PLTE; |
|
359 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
360 PNG_CONST PNG_bKGD; |
|
361 #endif |
|
362 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
363 PNG_CONST PNG_cHRM; |
|
364 #endif |
|
365 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
366 PNG_CONST PNG_gAMA; |
|
367 #endif |
|
368 #if defined(PNG_READ_hIST_SUPPORTED) |
|
369 PNG_CONST PNG_hIST; |
|
370 #endif |
|
371 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
372 PNG_CONST PNG_iCCP; |
|
373 #endif |
|
374 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
375 PNG_CONST PNG_iTXt; |
|
376 #endif |
|
377 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
378 PNG_CONST PNG_oFFs; |
|
379 #endif |
|
380 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
381 PNG_CONST PNG_pCAL; |
|
382 #endif |
|
383 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
384 PNG_CONST PNG_pHYs; |
|
385 #endif |
|
386 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
387 PNG_CONST PNG_sBIT; |
|
388 #endif |
|
389 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
390 PNG_CONST PNG_sCAL; |
|
391 #endif |
|
392 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
393 PNG_CONST PNG_sPLT; |
|
394 #endif |
|
395 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
396 PNG_CONST PNG_sRGB; |
|
397 #endif |
|
398 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
399 PNG_CONST PNG_tEXt; |
|
400 #endif |
|
401 #if defined(PNG_READ_tIME_SUPPORTED) |
|
402 PNG_CONST PNG_tIME; |
|
403 #endif |
|
404 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
405 PNG_CONST PNG_tRNS; |
|
406 #endif |
|
407 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
408 PNG_CONST PNG_zTXt; |
|
409 #endif |
|
410 #endif /* PNG_USE_LOCAL_ARRAYS */ |
|
411 png_uint_32 length = png_read_chunk_header(png_ptr); |
|
412 PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; |
|
413 |
|
414 /* This should be a binary subdivision search or a hash for |
|
415 * matching the chunk name rather than a linear search. |
|
416 */ |
|
417 if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
418 if (png_ptr->mode & PNG_AFTER_IDAT) |
|
419 png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; |
|
420 |
|
421 if (!png_memcmp(chunk_name, png_IHDR, 4)) |
|
422 png_handle_IHDR(png_ptr, info_ptr, length); |
|
423 else if (!png_memcmp(chunk_name, png_IEND, 4)) |
|
424 png_handle_IEND(png_ptr, info_ptr, length); |
|
425 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
|
426 else if (png_handle_as_unknown(png_ptr, chunk_name)) |
|
427 { |
|
428 if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
429 png_ptr->mode |= PNG_HAVE_IDAT; |
|
430 png_handle_unknown(png_ptr, info_ptr, length); |
|
431 if (!png_memcmp(chunk_name, png_PLTE, 4)) |
|
432 png_ptr->mode |= PNG_HAVE_PLTE; |
|
433 else if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
434 { |
|
435 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
436 png_error(png_ptr, "Missing IHDR before IDAT"); |
|
437 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
|
438 !(png_ptr->mode & PNG_HAVE_PLTE)) |
|
439 png_error(png_ptr, "Missing PLTE before IDAT"); |
|
440 break; |
|
441 } |
|
442 } |
|
443 #endif |
|
444 else if (!png_memcmp(chunk_name, png_PLTE, 4)) |
|
445 png_handle_PLTE(png_ptr, info_ptr, length); |
|
446 else if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
447 { |
|
448 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
449 png_error(png_ptr, "Missing IHDR before IDAT"); |
|
450 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
|
451 !(png_ptr->mode & PNG_HAVE_PLTE)) |
|
452 png_error(png_ptr, "Missing PLTE before IDAT"); |
|
453 |
|
454 png_ptr->idat_size = length; |
|
455 png_ptr->mode |= PNG_HAVE_IDAT; |
|
456 break; |
|
457 } |
|
458 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
459 else if (!png_memcmp(chunk_name, png_bKGD, 4)) |
|
460 png_handle_bKGD(png_ptr, info_ptr, length); |
|
461 #endif |
|
462 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
463 else if (!png_memcmp(chunk_name, png_cHRM, 4)) |
|
464 png_handle_cHRM(png_ptr, info_ptr, length); |
|
465 #endif |
|
466 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
467 else if (!png_memcmp(chunk_name, png_gAMA, 4)) |
|
468 png_handle_gAMA(png_ptr, info_ptr, length); |
|
469 #endif |
|
470 #if defined(PNG_READ_hIST_SUPPORTED) |
|
471 else if (!png_memcmp(chunk_name, png_hIST, 4)) |
|
472 png_handle_hIST(png_ptr, info_ptr, length); |
|
473 #endif |
|
474 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
475 else if (!png_memcmp(chunk_name, png_oFFs, 4)) |
|
476 png_handle_oFFs(png_ptr, info_ptr, length); |
|
477 #endif |
|
478 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
479 else if (!png_memcmp(chunk_name, png_pCAL, 4)) |
|
480 png_handle_pCAL(png_ptr, info_ptr, length); |
|
481 #endif |
|
482 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
483 else if (!png_memcmp(chunk_name, png_sCAL, 4)) |
|
484 png_handle_sCAL(png_ptr, info_ptr, length); |
|
485 #endif |
|
486 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
487 else if (!png_memcmp(chunk_name, png_pHYs, 4)) |
|
488 png_handle_pHYs(png_ptr, info_ptr, length); |
|
489 #endif |
|
490 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
491 else if (!png_memcmp(chunk_name, png_sBIT, 4)) |
|
492 png_handle_sBIT(png_ptr, info_ptr, length); |
|
493 #endif |
|
494 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
495 else if (!png_memcmp(chunk_name, png_sRGB, 4)) |
|
496 png_handle_sRGB(png_ptr, info_ptr, length); |
|
497 #endif |
|
498 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
499 else if (!png_memcmp(chunk_name, png_iCCP, 4)) |
|
500 png_handle_iCCP(png_ptr, info_ptr, length); |
|
501 #endif |
|
502 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
503 else if (!png_memcmp(chunk_name, png_sPLT, 4)) |
|
504 png_handle_sPLT(png_ptr, info_ptr, length); |
|
505 #endif |
|
506 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
507 else if (!png_memcmp(chunk_name, png_tEXt, 4)) |
|
508 png_handle_tEXt(png_ptr, info_ptr, length); |
|
509 #endif |
|
510 #if defined(PNG_READ_tIME_SUPPORTED) |
|
511 else if (!png_memcmp(chunk_name, png_tIME, 4)) |
|
512 png_handle_tIME(png_ptr, info_ptr, length); |
|
513 #endif |
|
514 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
515 else if (!png_memcmp(chunk_name, png_tRNS, 4)) |
|
516 png_handle_tRNS(png_ptr, info_ptr, length); |
|
517 #endif |
|
518 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
519 else if (!png_memcmp(chunk_name, png_zTXt, 4)) |
|
520 png_handle_zTXt(png_ptr, info_ptr, length); |
|
521 #endif |
|
522 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
523 else if (!png_memcmp(chunk_name, png_iTXt, 4)) |
|
524 png_handle_iTXt(png_ptr, info_ptr, length); |
|
525 #endif |
|
526 else |
|
527 png_handle_unknown(png_ptr, info_ptr, length); |
|
528 } |
|
529 } |
|
530 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
531 |
|
532 /* optional call to update the users info_ptr structure */ |
|
533 void PNGAPI |
|
534 png_read_update_info(png_structp png_ptr, png_infop info_ptr) |
|
535 { |
|
536 png_debug(1, "in png_read_update_info\n"); |
|
537 if (png_ptr == NULL) return; |
|
538 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
|
539 png_read_start_row(png_ptr); |
|
540 else |
|
541 png_warning(png_ptr, |
|
542 "Ignoring extra png_read_update_info() call; row buffer not reallocated"); |
|
543 png_read_transform_info(png_ptr, info_ptr); |
|
544 } |
|
545 |
|
546 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
547 /* Initialize palette, background, etc, after transformations |
|
548 * are set, but before any reading takes place. This allows |
|
549 * the user to obtain a gamma-corrected palette, for example. |
|
550 * If the user doesn't call this, we will do it ourselves. |
|
551 */ |
|
552 void PNGAPI |
|
553 png_start_read_image(png_structp png_ptr) |
|
554 { |
|
555 png_debug(1, "in png_start_read_image\n"); |
|
556 if (png_ptr == NULL) return; |
|
557 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
|
558 png_read_start_row(png_ptr); |
|
559 } |
|
560 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
561 |
|
562 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
563 void PNGAPI |
|
564 png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) |
|
565 { |
|
566 #ifdef PNG_USE_LOCAL_ARRAYS |
|
567 PNG_CONST PNG_IDAT; |
|
568 PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, |
|
569 0xff}; |
|
570 PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; |
|
571 #endif |
|
572 int ret; |
|
573 if (png_ptr == NULL) return; |
|
574 png_debug2(1, "in png_read_row (row %lu, pass %d)\n", |
|
575 png_ptr->row_number, png_ptr->pass); |
|
576 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
|
577 png_read_start_row(png_ptr); |
|
578 if (png_ptr->row_number == 0 && png_ptr->pass == 0) |
|
579 { |
|
580 /* check for transforms that have been set but were defined out */ |
|
581 #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED) |
|
582 if (png_ptr->transformations & PNG_INVERT_MONO) |
|
583 png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined."); |
|
584 #endif |
|
585 #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED) |
|
586 if (png_ptr->transformations & PNG_FILLER) |
|
587 png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined."); |
|
588 #endif |
|
589 #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
590 if (png_ptr->transformations & PNG_PACKSWAP) |
|
591 png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined."); |
|
592 #endif |
|
593 #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED) |
|
594 if (png_ptr->transformations & PNG_PACK) |
|
595 png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined."); |
|
596 #endif |
|
597 #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) |
|
598 if (png_ptr->transformations & PNG_SHIFT) |
|
599 png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined."); |
|
600 #endif |
|
601 #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED) |
|
602 if (png_ptr->transformations & PNG_BGR) |
|
603 png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined."); |
|
604 #endif |
|
605 #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED) |
|
606 if (png_ptr->transformations & PNG_SWAP_BYTES) |
|
607 png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined."); |
|
608 #endif |
|
609 } |
|
610 |
|
611 #if defined(PNG_READ_INTERLACING_SUPPORTED) |
|
612 /* if interlaced and we do not need a new row, combine row and return */ |
|
613 if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) |
|
614 { |
|
615 switch (png_ptr->pass) |
|
616 { |
|
617 case 0: |
|
618 if (png_ptr->row_number & 0x07) |
|
619 { |
|
620 if (dsp_row != NULL) |
|
621 png_combine_row(png_ptr, dsp_row, |
|
622 png_pass_dsp_mask[png_ptr->pass]); |
|
623 png_read_finish_row(png_ptr); |
|
624 return; |
|
625 } |
|
626 break; |
|
627 case 1: |
|
628 if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) |
|
629 { |
|
630 if (dsp_row != NULL) |
|
631 png_combine_row(png_ptr, dsp_row, |
|
632 png_pass_dsp_mask[png_ptr->pass]); |
|
633 png_read_finish_row(png_ptr); |
|
634 return; |
|
635 } |
|
636 break; |
|
637 case 2: |
|
638 if ((png_ptr->row_number & 0x07) != 4) |
|
639 { |
|
640 if (dsp_row != NULL && (png_ptr->row_number & 4)) |
|
641 png_combine_row(png_ptr, dsp_row, |
|
642 png_pass_dsp_mask[png_ptr->pass]); |
|
643 png_read_finish_row(png_ptr); |
|
644 return; |
|
645 } |
|
646 break; |
|
647 case 3: |
|
648 if ((png_ptr->row_number & 3) || png_ptr->width < 3) |
|
649 { |
|
650 if (dsp_row != NULL) |
|
651 png_combine_row(png_ptr, dsp_row, |
|
652 png_pass_dsp_mask[png_ptr->pass]); |
|
653 png_read_finish_row(png_ptr); |
|
654 return; |
|
655 } |
|
656 break; |
|
657 case 4: |
|
658 if ((png_ptr->row_number & 3) != 2) |
|
659 { |
|
660 if (dsp_row != NULL && (png_ptr->row_number & 2)) |
|
661 png_combine_row(png_ptr, dsp_row, |
|
662 png_pass_dsp_mask[png_ptr->pass]); |
|
663 png_read_finish_row(png_ptr); |
|
664 return; |
|
665 } |
|
666 break; |
|
667 case 5: |
|
668 if ((png_ptr->row_number & 1) || png_ptr->width < 2) |
|
669 { |
|
670 if (dsp_row != NULL) |
|
671 png_combine_row(png_ptr, dsp_row, |
|
672 png_pass_dsp_mask[png_ptr->pass]); |
|
673 png_read_finish_row(png_ptr); |
|
674 return; |
|
675 } |
|
676 break; |
|
677 case 6: |
|
678 if (!(png_ptr->row_number & 1)) |
|
679 { |
|
680 png_read_finish_row(png_ptr); |
|
681 return; |
|
682 } |
|
683 break; |
|
684 } |
|
685 } |
|
686 #endif |
|
687 |
|
688 if (!(png_ptr->mode & PNG_HAVE_IDAT)) |
|
689 png_error(png_ptr, "Invalid attempt to read row data"); |
|
690 |
|
691 png_ptr->zstream.next_out = png_ptr->row_buf; |
|
692 png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; |
|
693 do |
|
694 { |
|
695 if (!(png_ptr->zstream.avail_in)) |
|
696 { |
|
697 while (!png_ptr->idat_size) |
|
698 { |
|
699 png_crc_finish(png_ptr, 0); |
|
700 |
|
701 png_ptr->idat_size = png_read_chunk_header(png_ptr); |
|
702 if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
|
703 png_error(png_ptr, "Not enough image data"); |
|
704 } |
|
705 png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; |
|
706 png_ptr->zstream.next_in = png_ptr->zbuf; |
|
707 if (png_ptr->zbuf_size > png_ptr->idat_size) |
|
708 png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; |
|
709 png_crc_read(png_ptr, png_ptr->zbuf, |
|
710 (png_size_t)png_ptr->zstream.avail_in); |
|
711 png_ptr->idat_size -= png_ptr->zstream.avail_in; |
|
712 } |
|
713 ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); |
|
714 if (ret == Z_STREAM_END) |
|
715 { |
|
716 if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || |
|
717 png_ptr->idat_size) |
|
718 png_error(png_ptr, "Extra compressed data"); |
|
719 png_ptr->mode |= PNG_AFTER_IDAT; |
|
720 png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; |
|
721 break; |
|
722 } |
|
723 if (ret != Z_OK) |
|
724 png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : |
|
725 "Decompression error"); |
|
726 |
|
727 } while (png_ptr->zstream.avail_out); |
|
728 |
|
729 png_ptr->row_info.color_type = png_ptr->color_type; |
|
730 png_ptr->row_info.width = png_ptr->iwidth; |
|
731 png_ptr->row_info.channels = png_ptr->channels; |
|
732 png_ptr->row_info.bit_depth = png_ptr->bit_depth; |
|
733 png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; |
|
734 png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, |
|
735 png_ptr->row_info.width); |
|
736 |
|
737 if (png_ptr->row_buf[0]) |
|
738 png_read_filter_row(png_ptr, &(png_ptr->row_info), |
|
739 png_ptr->row_buf + 1, png_ptr->prev_row + 1, |
|
740 (int)(png_ptr->row_buf[0])); |
|
741 |
|
742 png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf, |
|
743 png_ptr->rowbytes + 1); |
|
744 |
|
745 #if defined(PNG_MNG_FEATURES_SUPPORTED) |
|
746 if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && |
|
747 (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) |
|
748 { |
|
749 /* Intrapixel differencing */ |
|
750 png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); |
|
751 } |
|
752 #endif |
|
753 |
|
754 |
|
755 if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) |
|
756 png_do_read_transformations(png_ptr); |
|
757 |
|
758 #if defined(PNG_READ_INTERLACING_SUPPORTED) |
|
759 /* blow up interlaced rows to full size */ |
|
760 if (png_ptr->interlaced && |
|
761 (png_ptr->transformations & PNG_INTERLACE)) |
|
762 { |
|
763 if (png_ptr->pass < 6) |
|
764 /* old interface (pre-1.0.9): |
|
765 png_do_read_interlace(&(png_ptr->row_info), |
|
766 png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); |
|
767 */ |
|
768 png_do_read_interlace(png_ptr); |
|
769 |
|
770 if (dsp_row != NULL) |
|
771 png_combine_row(png_ptr, dsp_row, |
|
772 png_pass_dsp_mask[png_ptr->pass]); |
|
773 if (row != NULL) |
|
774 png_combine_row(png_ptr, row, |
|
775 png_pass_mask[png_ptr->pass]); |
|
776 } |
|
777 else |
|
778 #endif |
|
779 { |
|
780 if (row != NULL) |
|
781 png_combine_row(png_ptr, row, 0xff); |
|
782 if (dsp_row != NULL) |
|
783 png_combine_row(png_ptr, dsp_row, 0xff); |
|
784 } |
|
785 png_read_finish_row(png_ptr); |
|
786 |
|
787 if (png_ptr->read_row_fn != NULL) |
|
788 (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); |
|
789 } |
|
790 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
791 |
|
792 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
793 /* Read one or more rows of image data. If the image is interlaced, |
|
794 * and png_set_interlace_handling() has been called, the rows need to |
|
795 * contain the contents of the rows from the previous pass. If the |
|
796 * image has alpha or transparency, and png_handle_alpha()[*] has been |
|
797 * called, the rows contents must be initialized to the contents of the |
|
798 * screen. |
|
799 * |
|
800 * "row" holds the actual image, and pixels are placed in it |
|
801 * as they arrive. If the image is displayed after each pass, it will |
|
802 * appear to "sparkle" in. "display_row" can be used to display a |
|
803 * "chunky" progressive image, with finer detail added as it becomes |
|
804 * available. If you do not want this "chunky" display, you may pass |
|
805 * NULL for display_row. If you do not want the sparkle display, and |
|
806 * you have not called png_handle_alpha(), you may pass NULL for rows. |
|
807 * If you have called png_handle_alpha(), and the image has either an |
|
808 * alpha channel or a transparency chunk, you must provide a buffer for |
|
809 * rows. In this case, you do not have to provide a display_row buffer |
|
810 * also, but you may. If the image is not interlaced, or if you have |
|
811 * not called png_set_interlace_handling(), the display_row buffer will |
|
812 * be ignored, so pass NULL to it. |
|
813 * |
|
814 * [*] png_handle_alpha() does not exist yet, as of this version of libpng |
|
815 */ |
|
816 |
|
817 void PNGAPI |
|
818 png_read_rows(png_structp png_ptr, png_bytepp row, |
|
819 png_bytepp display_row, png_uint_32 num_rows) |
|
820 { |
|
821 png_uint_32 i; |
|
822 png_bytepp rp; |
|
823 png_bytepp dp; |
|
824 |
|
825 png_debug(1, "in png_read_rows\n"); |
|
826 if (png_ptr == NULL) return; |
|
827 rp = row; |
|
828 dp = display_row; |
|
829 if (rp != NULL && dp != NULL) |
|
830 for (i = 0; i < num_rows; i++) |
|
831 { |
|
832 png_bytep rptr = *rp++; |
|
833 png_bytep dptr = *dp++; |
|
834 |
|
835 png_read_row(png_ptr, rptr, dptr); |
|
836 } |
|
837 else if (rp != NULL) |
|
838 for (i = 0; i < num_rows; i++) |
|
839 { |
|
840 png_bytep rptr = *rp; |
|
841 png_read_row(png_ptr, rptr, png_bytep_NULL); |
|
842 rp++; |
|
843 } |
|
844 else if (dp != NULL) |
|
845 for (i = 0; i < num_rows; i++) |
|
846 { |
|
847 png_bytep dptr = *dp; |
|
848 png_read_row(png_ptr, png_bytep_NULL, dptr); |
|
849 dp++; |
|
850 } |
|
851 } |
|
852 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
853 |
|
854 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
855 /* Read the entire image. If the image has an alpha channel or a tRNS |
|
856 * chunk, and you have called png_handle_alpha()[*], you will need to |
|
857 * initialize the image to the current image that PNG will be overlaying. |
|
858 * We set the num_rows again here, in case it was incorrectly set in |
|
859 * png_read_start_row() by a call to png_read_update_info() or |
|
860 * png_start_read_image() if png_set_interlace_handling() wasn't called |
|
861 * prior to either of these functions like it should have been. You can |
|
862 * only call this function once. If you desire to have an image for |
|
863 * each pass of a interlaced image, use png_read_rows() instead. |
|
864 * |
|
865 * [*] png_handle_alpha() does not exist yet, as of this version of libpng |
|
866 */ |
|
867 void PNGAPI |
|
868 png_read_image(png_structp png_ptr, png_bytepp image) |
|
869 { |
|
870 png_uint_32 i, image_height; |
|
871 int pass, j; |
|
872 png_bytepp rp; |
|
873 |
|
874 png_debug(1, "in png_read_image\n"); |
|
875 if (png_ptr == NULL) return; |
|
876 |
|
877 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
878 pass = png_set_interlace_handling(png_ptr); |
|
879 #else |
|
880 if (png_ptr->interlaced) |
|
881 png_error(png_ptr, |
|
882 "Cannot read interlaced image -- interlace handler disabled."); |
|
883 pass = 1; |
|
884 #endif |
|
885 |
|
886 |
|
887 image_height=png_ptr->height; |
|
888 png_ptr->num_rows = image_height; /* Make sure this is set correctly */ |
|
889 |
|
890 for (j = 0; j < pass; j++) |
|
891 { |
|
892 rp = image; |
|
893 for (i = 0; i < image_height; i++) |
|
894 { |
|
895 png_read_row(png_ptr, *rp, png_bytep_NULL); |
|
896 rp++; |
|
897 } |
|
898 } |
|
899 } |
|
900 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
901 |
|
902 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
903 /* Read the end of the PNG file. Will not read past the end of the |
|
904 * file, will verify the end is accurate, and will read any comments |
|
905 * or time information at the end of the file, if info is not NULL. |
|
906 */ |
|
907 void PNGAPI |
|
908 png_read_end(png_structp png_ptr, png_infop info_ptr) |
|
909 { |
|
910 png_debug(1, "in png_read_end\n"); |
|
911 if (png_ptr == NULL) return; |
|
912 png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ |
|
913 |
|
914 do |
|
915 { |
|
916 #ifdef PNG_USE_LOCAL_ARRAYS |
|
917 PNG_CONST PNG_IHDR; |
|
918 PNG_CONST PNG_IDAT; |
|
919 PNG_CONST PNG_IEND; |
|
920 PNG_CONST PNG_PLTE; |
|
921 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
922 PNG_CONST PNG_bKGD; |
|
923 #endif |
|
924 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
925 PNG_CONST PNG_cHRM; |
|
926 #endif |
|
927 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
928 PNG_CONST PNG_gAMA; |
|
929 #endif |
|
930 #if defined(PNG_READ_hIST_SUPPORTED) |
|
931 PNG_CONST PNG_hIST; |
|
932 #endif |
|
933 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
934 PNG_CONST PNG_iCCP; |
|
935 #endif |
|
936 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
937 PNG_CONST PNG_iTXt; |
|
938 #endif |
|
939 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
940 PNG_CONST PNG_oFFs; |
|
941 #endif |
|
942 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
943 PNG_CONST PNG_pCAL; |
|
944 #endif |
|
945 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
946 PNG_CONST PNG_pHYs; |
|
947 #endif |
|
948 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
949 PNG_CONST PNG_sBIT; |
|
950 #endif |
|
951 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
952 PNG_CONST PNG_sCAL; |
|
953 #endif |
|
954 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
955 PNG_CONST PNG_sPLT; |
|
956 #endif |
|
957 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
958 PNG_CONST PNG_sRGB; |
|
959 #endif |
|
960 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
961 PNG_CONST PNG_tEXt; |
|
962 #endif |
|
963 #if defined(PNG_READ_tIME_SUPPORTED) |
|
964 PNG_CONST PNG_tIME; |
|
965 #endif |
|
966 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
967 PNG_CONST PNG_tRNS; |
|
968 #endif |
|
969 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
970 PNG_CONST PNG_zTXt; |
|
971 #endif |
|
972 #endif /* PNG_USE_LOCAL_ARRAYS */ |
|
973 png_uint_32 length = png_read_chunk_header(png_ptr); |
|
974 PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; |
|
975 |
|
976 if (!png_memcmp(chunk_name, png_IHDR, 4)) |
|
977 png_handle_IHDR(png_ptr, info_ptr, length); |
|
978 else if (!png_memcmp(chunk_name, png_IEND, 4)) |
|
979 png_handle_IEND(png_ptr, info_ptr, length); |
|
980 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
|
981 else if (png_handle_as_unknown(png_ptr, chunk_name)) |
|
982 { |
|
983 if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
984 { |
|
985 if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) |
|
986 png_error(png_ptr, "Too many IDAT's found"); |
|
987 } |
|
988 png_handle_unknown(png_ptr, info_ptr, length); |
|
989 if (!png_memcmp(chunk_name, png_PLTE, 4)) |
|
990 png_ptr->mode |= PNG_HAVE_PLTE; |
|
991 } |
|
992 #endif |
|
993 else if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
994 { |
|
995 /* Zero length IDATs are legal after the last IDAT has been |
|
996 * read, but not after other chunks have been read. |
|
997 */ |
|
998 if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) |
|
999 png_error(png_ptr, "Too many IDAT's found"); |
|
1000 png_crc_finish(png_ptr, length); |
|
1001 } |
|
1002 else if (!png_memcmp(chunk_name, png_PLTE, 4)) |
|
1003 png_handle_PLTE(png_ptr, info_ptr, length); |
|
1004 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
1005 else if (!png_memcmp(chunk_name, png_bKGD, 4)) |
|
1006 png_handle_bKGD(png_ptr, info_ptr, length); |
|
1007 #endif |
|
1008 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
1009 else if (!png_memcmp(chunk_name, png_cHRM, 4)) |
|
1010 png_handle_cHRM(png_ptr, info_ptr, length); |
|
1011 #endif |
|
1012 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
1013 else if (!png_memcmp(chunk_name, png_gAMA, 4)) |
|
1014 png_handle_gAMA(png_ptr, info_ptr, length); |
|
1015 #endif |
|
1016 #if defined(PNG_READ_hIST_SUPPORTED) |
|
1017 else if (!png_memcmp(chunk_name, png_hIST, 4)) |
|
1018 png_handle_hIST(png_ptr, info_ptr, length); |
|
1019 #endif |
|
1020 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
1021 else if (!png_memcmp(chunk_name, png_oFFs, 4)) |
|
1022 png_handle_oFFs(png_ptr, info_ptr, length); |
|
1023 #endif |
|
1024 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
1025 else if (!png_memcmp(chunk_name, png_pCAL, 4)) |
|
1026 png_handle_pCAL(png_ptr, info_ptr, length); |
|
1027 #endif |
|
1028 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
1029 else if (!png_memcmp(chunk_name, png_sCAL, 4)) |
|
1030 png_handle_sCAL(png_ptr, info_ptr, length); |
|
1031 #endif |
|
1032 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
1033 else if (!png_memcmp(chunk_name, png_pHYs, 4)) |
|
1034 png_handle_pHYs(png_ptr, info_ptr, length); |
|
1035 #endif |
|
1036 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
1037 else if (!png_memcmp(chunk_name, png_sBIT, 4)) |
|
1038 png_handle_sBIT(png_ptr, info_ptr, length); |
|
1039 #endif |
|
1040 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
1041 else if (!png_memcmp(chunk_name, png_sRGB, 4)) |
|
1042 png_handle_sRGB(png_ptr, info_ptr, length); |
|
1043 #endif |
|
1044 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
1045 else if (!png_memcmp(chunk_name, png_iCCP, 4)) |
|
1046 png_handle_iCCP(png_ptr, info_ptr, length); |
|
1047 #endif |
|
1048 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
1049 else if (!png_memcmp(chunk_name, png_sPLT, 4)) |
|
1050 png_handle_sPLT(png_ptr, info_ptr, length); |
|
1051 #endif |
|
1052 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
1053 else if (!png_memcmp(chunk_name, png_tEXt, 4)) |
|
1054 png_handle_tEXt(png_ptr, info_ptr, length); |
|
1055 #endif |
|
1056 #if defined(PNG_READ_tIME_SUPPORTED) |
|
1057 else if (!png_memcmp(chunk_name, png_tIME, 4)) |
|
1058 png_handle_tIME(png_ptr, info_ptr, length); |
|
1059 #endif |
|
1060 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
1061 else if (!png_memcmp(chunk_name, png_tRNS, 4)) |
|
1062 png_handle_tRNS(png_ptr, info_ptr, length); |
|
1063 #endif |
|
1064 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
1065 else if (!png_memcmp(chunk_name, png_zTXt, 4)) |
|
1066 png_handle_zTXt(png_ptr, info_ptr, length); |
|
1067 #endif |
|
1068 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
1069 else if (!png_memcmp(chunk_name, png_iTXt, 4)) |
|
1070 png_handle_iTXt(png_ptr, info_ptr, length); |
|
1071 #endif |
|
1072 else |
|
1073 png_handle_unknown(png_ptr, info_ptr, length); |
|
1074 } while (!(png_ptr->mode & PNG_HAVE_IEND)); |
|
1075 } |
|
1076 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
1077 |
|
1078 /* free all memory used by the read */ |
|
1079 void PNGAPI |
|
1080 png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, |
|
1081 png_infopp end_info_ptr_ptr) |
|
1082 { |
|
1083 png_structp png_ptr = NULL; |
|
1084 png_infop info_ptr = NULL, end_info_ptr = NULL; |
|
1085 #ifdef PNG_USER_MEM_SUPPORTED |
|
1086 png_free_ptr free_fn = NULL; |
|
1087 png_voidp mem_ptr = NULL; |
|
1088 #endif |
|
1089 |
|
1090 png_debug(1, "in png_destroy_read_struct\n"); |
|
1091 if (png_ptr_ptr != NULL) |
|
1092 png_ptr = *png_ptr_ptr; |
|
1093 if (png_ptr == NULL) |
|
1094 return; |
|
1095 |
|
1096 #ifdef PNG_USER_MEM_SUPPORTED |
|
1097 free_fn = png_ptr->free_fn; |
|
1098 mem_ptr = png_ptr->mem_ptr; |
|
1099 #endif |
|
1100 |
|
1101 if (info_ptr_ptr != NULL) |
|
1102 info_ptr = *info_ptr_ptr; |
|
1103 |
|
1104 if (end_info_ptr_ptr != NULL) |
|
1105 end_info_ptr = *end_info_ptr_ptr; |
|
1106 |
|
1107 png_read_destroy(png_ptr, info_ptr, end_info_ptr); |
|
1108 |
|
1109 if (info_ptr != NULL) |
|
1110 { |
|
1111 #if defined(PNG_TEXT_SUPPORTED) |
|
1112 png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1); |
|
1113 #endif |
|
1114 |
|
1115 #ifdef PNG_USER_MEM_SUPPORTED |
|
1116 png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, |
|
1117 (png_voidp)mem_ptr); |
|
1118 #else |
|
1119 png_destroy_struct((png_voidp)info_ptr); |
|
1120 #endif |
|
1121 *info_ptr_ptr = NULL; |
|
1122 } |
|
1123 |
|
1124 if (end_info_ptr != NULL) |
|
1125 { |
|
1126 #if defined(PNG_READ_TEXT_SUPPORTED) |
|
1127 png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1); |
|
1128 #endif |
|
1129 #ifdef PNG_USER_MEM_SUPPORTED |
|
1130 png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn, |
|
1131 (png_voidp)mem_ptr); |
|
1132 #else |
|
1133 png_destroy_struct((png_voidp)end_info_ptr); |
|
1134 #endif |
|
1135 *end_info_ptr_ptr = NULL; |
|
1136 } |
|
1137 |
|
1138 if (png_ptr != NULL) |
|
1139 { |
|
1140 #ifdef PNG_USER_MEM_SUPPORTED |
|
1141 png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, |
|
1142 (png_voidp)mem_ptr); |
|
1143 #else |
|
1144 png_destroy_struct((png_voidp)png_ptr); |
|
1145 #endif |
|
1146 *png_ptr_ptr = NULL; |
|
1147 } |
|
1148 } |
|
1149 |
|
1150 /* free all memory used by the read (old method) */ |
|
1151 void /* PRIVATE */ |
|
1152 png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr) |
|
1153 { |
|
1154 #ifdef PNG_SETJMP_SUPPORTED |
|
1155 jmp_buf tmp_jmp; |
|
1156 #endif |
|
1157 png_error_ptr error_fn; |
|
1158 png_error_ptr warning_fn; |
|
1159 png_voidp error_ptr; |
|
1160 #ifdef PNG_USER_MEM_SUPPORTED |
|
1161 png_free_ptr free_fn; |
|
1162 #endif |
|
1163 |
|
1164 png_debug(1, "in png_read_destroy\n"); |
|
1165 if (info_ptr != NULL) |
|
1166 png_info_destroy(png_ptr, info_ptr); |
|
1167 |
|
1168 if (end_info_ptr != NULL) |
|
1169 png_info_destroy(png_ptr, end_info_ptr); |
|
1170 |
|
1171 png_free(png_ptr, png_ptr->zbuf); |
|
1172 png_free(png_ptr, png_ptr->big_row_buf); |
|
1173 png_free(png_ptr, png_ptr->prev_row); |
|
1174 png_free(png_ptr, png_ptr->chunkdata); |
|
1175 #if defined(PNG_READ_DITHER_SUPPORTED) |
|
1176 png_free(png_ptr, png_ptr->palette_lookup); |
|
1177 png_free(png_ptr, png_ptr->dither_index); |
|
1178 #endif |
|
1179 #if defined(PNG_READ_GAMMA_SUPPORTED) |
|
1180 png_free(png_ptr, png_ptr->gamma_table); |
|
1181 #endif |
|
1182 #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
|
1183 png_free(png_ptr, png_ptr->gamma_from_1); |
|
1184 png_free(png_ptr, png_ptr->gamma_to_1); |
|
1185 #endif |
|
1186 #ifdef PNG_FREE_ME_SUPPORTED |
|
1187 if (png_ptr->free_me & PNG_FREE_PLTE) |
|
1188 png_zfree(png_ptr, png_ptr->palette); |
|
1189 png_ptr->free_me &= ~PNG_FREE_PLTE; |
|
1190 #else |
|
1191 if (png_ptr->flags & PNG_FLAG_FREE_PLTE) |
|
1192 png_zfree(png_ptr, png_ptr->palette); |
|
1193 png_ptr->flags &= ~PNG_FLAG_FREE_PLTE; |
|
1194 #endif |
|
1195 #if defined(PNG_tRNS_SUPPORTED) || \ |
|
1196 defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) |
|
1197 #ifdef PNG_FREE_ME_SUPPORTED |
|
1198 if (png_ptr->free_me & PNG_FREE_TRNS) |
|
1199 png_free(png_ptr, png_ptr->trans); |
|
1200 png_ptr->free_me &= ~PNG_FREE_TRNS; |
|
1201 #else |
|
1202 if (png_ptr->flags & PNG_FLAG_FREE_TRNS) |
|
1203 png_free(png_ptr, png_ptr->trans); |
|
1204 png_ptr->flags &= ~PNG_FLAG_FREE_TRNS; |
|
1205 #endif |
|
1206 #endif |
|
1207 #if defined(PNG_READ_hIST_SUPPORTED) |
|
1208 #ifdef PNG_FREE_ME_SUPPORTED |
|
1209 if (png_ptr->free_me & PNG_FREE_HIST) |
|
1210 png_free(png_ptr, png_ptr->hist); |
|
1211 png_ptr->free_me &= ~PNG_FREE_HIST; |
|
1212 #else |
|
1213 if (png_ptr->flags & PNG_FLAG_FREE_HIST) |
|
1214 png_free(png_ptr, png_ptr->hist); |
|
1215 png_ptr->flags &= ~PNG_FLAG_FREE_HIST; |
|
1216 #endif |
|
1217 #endif |
|
1218 #if defined(PNG_READ_GAMMA_SUPPORTED) |
|
1219 if (png_ptr->gamma_16_table != NULL) |
|
1220 { |
|
1221 int i; |
|
1222 int istop = (1 << (8 - png_ptr->gamma_shift)); |
|
1223 for (i = 0; i < istop; i++) |
|
1224 { |
|
1225 png_free(png_ptr, png_ptr->gamma_16_table[i]); |
|
1226 } |
|
1227 png_free(png_ptr, png_ptr->gamma_16_table); |
|
1228 } |
|
1229 #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
|
1230 if (png_ptr->gamma_16_from_1 != NULL) |
|
1231 { |
|
1232 int i; |
|
1233 int istop = (1 << (8 - png_ptr->gamma_shift)); |
|
1234 for (i = 0; i < istop; i++) |
|
1235 { |
|
1236 png_free(png_ptr, png_ptr->gamma_16_from_1[i]); |
|
1237 } |
|
1238 png_free(png_ptr, png_ptr->gamma_16_from_1); |
|
1239 } |
|
1240 if (png_ptr->gamma_16_to_1 != NULL) |
|
1241 { |
|
1242 int i; |
|
1243 int istop = (1 << (8 - png_ptr->gamma_shift)); |
|
1244 for (i = 0; i < istop; i++) |
|
1245 { |
|
1246 png_free(png_ptr, png_ptr->gamma_16_to_1[i]); |
|
1247 } |
|
1248 png_free(png_ptr, png_ptr->gamma_16_to_1); |
|
1249 } |
|
1250 #endif |
|
1251 #endif |
|
1252 #if defined(PNG_TIME_RFC1123_SUPPORTED) |
|
1253 png_free(png_ptr, png_ptr->time_buffer); |
|
1254 #endif |
|
1255 |
|
1256 inflateEnd(&png_ptr->zstream); |
|
1257 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
1258 png_free(png_ptr, png_ptr->save_buffer); |
|
1259 #endif |
|
1260 |
|
1261 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
1262 #ifdef PNG_TEXT_SUPPORTED |
|
1263 png_free(png_ptr, png_ptr->current_text); |
|
1264 #endif /* PNG_TEXT_SUPPORTED */ |
|
1265 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ |
|
1266 |
|
1267 /* Save the important info out of the png_struct, in case it is |
|
1268 * being used again. |
|
1269 */ |
|
1270 #ifdef PNG_SETJMP_SUPPORTED |
|
1271 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf)); |
|
1272 #endif |
|
1273 |
|
1274 error_fn = png_ptr->error_fn; |
|
1275 warning_fn = png_ptr->warning_fn; |
|
1276 error_ptr = png_ptr->error_ptr; |
|
1277 #ifdef PNG_USER_MEM_SUPPORTED |
|
1278 free_fn = png_ptr->free_fn; |
|
1279 #endif |
|
1280 |
|
1281 png_memset(png_ptr, 0, png_sizeof(png_struct)); |
|
1282 |
|
1283 png_ptr->error_fn = error_fn; |
|
1284 png_ptr->warning_fn = warning_fn; |
|
1285 png_ptr->error_ptr = error_ptr; |
|
1286 #ifdef PNG_USER_MEM_SUPPORTED |
|
1287 png_ptr->free_fn = free_fn; |
|
1288 #endif |
|
1289 |
|
1290 #ifdef PNG_SETJMP_SUPPORTED |
|
1291 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); |
|
1292 #endif |
|
1293 |
|
1294 } |
|
1295 |
|
1296 void PNGAPI |
|
1297 png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) |
|
1298 { |
|
1299 if (png_ptr == NULL) return; |
|
1300 png_ptr->read_row_fn = read_row_fn; |
|
1301 } |
|
1302 |
|
1303 |
|
1304 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
1305 #if defined(PNG_INFO_IMAGE_SUPPORTED) |
|
1306 void PNGAPI |
|
1307 png_read_png(png_structp png_ptr, png_infop info_ptr, |
|
1308 int transforms, |
|
1309 voidp params) |
|
1310 { |
|
1311 int row; |
|
1312 |
|
1313 if (png_ptr == NULL) return; |
|
1314 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) |
|
1315 /* invert the alpha channel from opacity to transparency |
|
1316 */ |
|
1317 if (transforms & PNG_TRANSFORM_INVERT_ALPHA) |
|
1318 png_set_invert_alpha(png_ptr); |
|
1319 #endif |
|
1320 |
|
1321 /* png_read_info() gives us all of the information from the |
|
1322 * PNG file before the first IDAT (image data chunk). |
|
1323 */ |
|
1324 png_read_info(png_ptr, info_ptr); |
|
1325 if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep)) |
|
1326 png_error(png_ptr, "Image is too high to process with png_read_png()"); |
|
1327 |
|
1328 /* -------------- image transformations start here ------------------- */ |
|
1329 |
|
1330 #if defined(PNG_READ_16_TO_8_SUPPORTED) |
|
1331 /* tell libpng to strip 16 bit/color files down to 8 bits per color |
|
1332 */ |
|
1333 if (transforms & PNG_TRANSFORM_STRIP_16) |
|
1334 png_set_strip_16(png_ptr); |
|
1335 #endif |
|
1336 |
|
1337 #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
|
1338 /* Strip alpha bytes from the input data without combining with |
|
1339 * the background (not recommended). |
|
1340 */ |
|
1341 if (transforms & PNG_TRANSFORM_STRIP_ALPHA) |
|
1342 png_set_strip_alpha(png_ptr); |
|
1343 #endif |
|
1344 |
|
1345 #if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED) |
|
1346 /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single |
|
1347 * byte into separate bytes (useful for paletted and grayscale images). |
|
1348 */ |
|
1349 if (transforms & PNG_TRANSFORM_PACKING) |
|
1350 png_set_packing(png_ptr); |
|
1351 #endif |
|
1352 |
|
1353 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
1354 /* Change the order of packed pixels to least significant bit first |
|
1355 * (not useful if you are using png_set_packing). |
|
1356 */ |
|
1357 if (transforms & PNG_TRANSFORM_PACKSWAP) |
|
1358 png_set_packswap(png_ptr); |
|
1359 #endif |
|
1360 |
|
1361 #if defined(PNG_READ_EXPAND_SUPPORTED) |
|
1362 /* Expand paletted colors into true RGB triplets |
|
1363 * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel |
|
1364 * Expand paletted or RGB images with transparency to full alpha |
|
1365 * channels so the data will be available as RGBA quartets. |
|
1366 */ |
|
1367 if (transforms & PNG_TRANSFORM_EXPAND) |
|
1368 if ((png_ptr->bit_depth < 8) || |
|
1369 (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) || |
|
1370 (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))) |
|
1371 png_set_expand(png_ptr); |
|
1372 #endif |
|
1373 |
|
1374 /* We don't handle background color or gamma transformation or dithering. |
|
1375 */ |
|
1376 |
|
1377 #if defined(PNG_READ_INVERT_SUPPORTED) |
|
1378 /* invert monochrome files to have 0 as white and 1 as black |
|
1379 */ |
|
1380 if (transforms & PNG_TRANSFORM_INVERT_MONO) |
|
1381 png_set_invert_mono(png_ptr); |
|
1382 #endif |
|
1383 |
|
1384 #if defined(PNG_READ_SHIFT_SUPPORTED) |
|
1385 /* If you want to shift the pixel values from the range [0,255] or |
|
1386 * [0,65535] to the original [0,7] or [0,31], or whatever range the |
|
1387 * colors were originally in: |
|
1388 */ |
|
1389 if ((transforms & PNG_TRANSFORM_SHIFT) |
|
1390 && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) |
|
1391 { |
|
1392 png_color_8p sig_bit; |
|
1393 |
|
1394 png_get_sBIT(png_ptr, info_ptr, &sig_bit); |
|
1395 png_set_shift(png_ptr, sig_bit); |
|
1396 } |
|
1397 #endif |
|
1398 |
|
1399 #if defined(PNG_READ_BGR_SUPPORTED) |
|
1400 /* flip the RGB pixels to BGR (or RGBA to BGRA) |
|
1401 */ |
|
1402 if (transforms & PNG_TRANSFORM_BGR) |
|
1403 png_set_bgr(png_ptr); |
|
1404 #endif |
|
1405 |
|
1406 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) |
|
1407 /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) |
|
1408 */ |
|
1409 if (transforms & PNG_TRANSFORM_SWAP_ALPHA) |
|
1410 png_set_swap_alpha(png_ptr); |
|
1411 #endif |
|
1412 |
|
1413 #if defined(PNG_READ_SWAP_SUPPORTED) |
|
1414 /* swap bytes of 16 bit files to least significant byte first |
|
1415 */ |
|
1416 if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) |
|
1417 png_set_swap(png_ptr); |
|
1418 #endif |
|
1419 |
|
1420 /* We don't handle adding filler bytes */ |
|
1421 |
|
1422 /* Optional call to gamma correct and add the background to the palette |
|
1423 * and update info structure. REQUIRED if you are expecting libpng to |
|
1424 * update the palette for you (i.e., you selected such a transform above). |
|
1425 */ |
|
1426 png_read_update_info(png_ptr, info_ptr); |
|
1427 |
|
1428 /* -------------- image transformations end here ------------------- */ |
|
1429 |
|
1430 #ifdef PNG_FREE_ME_SUPPORTED |
|
1431 png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); |
|
1432 #endif |
|
1433 if (info_ptr->row_pointers == NULL) |
|
1434 { |
|
1435 info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr, |
|
1436 info_ptr->height * png_sizeof(png_bytep)); |
|
1437 #ifdef PNG_FREE_ME_SUPPORTED |
|
1438 info_ptr->free_me |= PNG_FREE_ROWS; |
|
1439 #endif |
|
1440 for (row = 0; row < (int)info_ptr->height; row++) |
|
1441 { |
|
1442 info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr, |
|
1443 png_get_rowbytes(png_ptr, info_ptr)); |
|
1444 } |
|
1445 } |
|
1446 |
|
1447 png_read_image(png_ptr, info_ptr->row_pointers); |
|
1448 info_ptr->valid |= PNG_INFO_IDAT; |
|
1449 |
|
1450 /* read rest of file, and get additional chunks in info_ptr - REQUIRED */ |
|
1451 png_read_end(png_ptr, info_ptr); |
|
1452 |
|
1453 transforms = transforms; /* quiet compiler warnings */ |
|
1454 params = params; |
|
1455 |
|
1456 } |
|
1457 #endif /* PNG_INFO_IMAGE_SUPPORTED */ |
|
1458 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
1459 #endif /* PNG_READ_SUPPORTED */ |