1 /*
2 ==============================================================================
3
4 This file is part of the JUCE library.
5 Copyright (c) 2020 - Raw Material Software Limited
6
7 JUCE is an open source library subject to commercial or open-source
8 licensing.
9
10 By using JUCE, you agree to the terms of both the JUCE 6 End-User License
11 Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).
12
13 End User License Agreement: www.juce.com/juce-6-licence
14 Privacy Policy: www.juce.com/juce-privacy-policy
15
16 Or: You may also use this code under the terms of the GPL v3 (see
17 www.gnu.org/licenses).
18
19 JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
20 EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
21 DISCLAIMED.
22
23 ==============================================================================
24 */
25
26 namespace juce
27 {
28
29 JUCE_BEGIN_IGNORE_WARNINGS_MSVC (4390 4611 4365 4267 4616 2544 2545)
30
31 namespace zlibNamespace
32 {
33 #if JUCE_INCLUDE_ZLIB_CODE
34 #undef OS_CODE
35 #undef fdopen
36 #define ZLIB_INTERNAL
37 #define NO_DUMMY_DECL
38 #include <juce_core/zip/zlib/zlib.h>
39 #undef OS_CODE
40 #else
41 #include JUCE_ZLIB_INCLUDE_PATH
42 #endif
43 }
44
45 #if ! defined (jmp_buf) || ! defined (longjmp)
46 #include <setjmp.h>
47 #endif
48
49 namespace pnglibNamespace
50 {
51 using namespace zlibNamespace;
52
53 #if JUCE_INCLUDE_PNGLIB_CODE || ! defined (JUCE_INCLUDE_PNGLIB_CODE)
54
55 #if _MSC_VER != 1310
56 using std::calloc; // (causes conflict in VS.NET 2003)
57 using std::malloc;
58 using std::free;
59 #endif
60
61 JUCE_BEGIN_IGNORE_WARNINGS_GCC_LIKE ("-Wsign-conversion",
62 "-Wimplicit-fallthrough",
63 "-Wtautological-constant-out-of-range-compare",
64 "-Wzero-as-null-pointer-constant",
65 "-Wcomma")
66
67 #undef check
68 using std::abs;
69 #define NO_DUMMY_DECL
70 #define PNGLCONF_H 1
71
72 #if JUCE_ANDROID
73 #define PNG_ARM_NEON_SUPPORTED
74 #endif
75
76 #ifndef Byte
77 using Byte = uint8_t;
78 #endif
79
80 #define PNG_16BIT_SUPPORTED
81 #define PNG_ALIGNED_MEMORY_SUPPORTED
82 #define PNG_BENIGN_ERRORS_SUPPORTED
83 #define PNG_BENIGN_READ_ERRORS_SUPPORTED
84 #define PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
85 #define PNG_COLORSPACE_SUPPORTED
86 #define PNG_CONSOLE_IO_SUPPORTED
87 #define PNG_EASY_ACCESS_SUPPORTED
88 #define PNG_FIXED_POINT_SUPPORTED
89 #define PNG_FLOATING_ARITHMETIC_SUPPORTED
90 #define PNG_FLOATING_POINT_SUPPORTED
91 #define PNG_FORMAT_AFIRST_SUPPORTED
92 #define PNG_FORMAT_BGR_SUPPORTED
93 #define PNG_GAMMA_SUPPORTED
94 #define PNG_GET_PALETTE_MAX_SUPPORTED
95 #define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
96 #define PNG_INCH_CONVERSIONS_SUPPORTED
97 #define PNG_INFO_IMAGE_SUPPORTED
98 #define PNG_IO_STATE_SUPPORTED
99 #define PNG_POINTER_INDEXING_SUPPORTED
100 #define PNG_PROGRESSIVE_READ_SUPPORTED
101 #define PNG_READ_16BIT_SUPPORTED
102 #define PNG_READ_ALPHA_MODE_SUPPORTED
103 #define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
104 #define PNG_READ_BACKGROUND_SUPPORTED
105 #define PNG_READ_BGR_SUPPORTED
106 #define PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
107 #define PNG_READ_COMPOSITE_NODIV_SUPPORTED
108 #define PNG_READ_COMPRESSED_TEXT_SUPPORTED
109 #define PNG_READ_EXPAND_16_SUPPORTED
110 #define PNG_READ_EXPAND_SUPPORTED
111 #define PNG_READ_FILLER_SUPPORTED
112 #define PNG_READ_GAMMA_SUPPORTED
113 #define PNG_READ_GET_PALETTE_MAX_SUPPORTED
114 #define PNG_READ_GRAY_TO_RGB_SUPPORTED
115 #define PNG_READ_INTERLACING_SUPPORTED
116 #define PNG_READ_INT_FUNCTIONS_SUPPORTED
117 #define PNG_READ_INVERT_ALPHA_SUPPORTED
118 #define PNG_READ_INVERT_SUPPORTED
119 #define PNG_READ_OPT_PLTE_SUPPORTED
120 #define PNG_READ_PACKSWAP_SUPPORTED
121 #define PNG_READ_PACK_SUPPORTED
122 #define PNG_READ_QUANTIZE_SUPPORTED
123 #define PNG_READ_RGB_TO_GRAY_SUPPORTED
124 #define PNG_READ_SCALE_16_TO_8_SUPPORTED
125 #define PNG_READ_SHIFT_SUPPORTED
126 #define PNG_READ_STRIP_16_TO_8_SUPPORTED
127 #define PNG_READ_STRIP_ALPHA_SUPPORTED
128 #define PNG_READ_SUPPORTED
129 #define PNG_READ_SWAP_ALPHA_SUPPORTED
130 #define PNG_READ_SWAP_SUPPORTED
131 #define PNG_READ_TEXT_SUPPORTED
132 #define PNG_READ_TRANSFORMS_SUPPORTED
133 #define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
134 #define PNG_READ_USER_CHUNKS_SUPPORTED
135 #define PNG_READ_USER_TRANSFORM_SUPPORTED
136 #define PNG_READ_bKGD_SUPPORTED
137 #define PNG_READ_cHRM_SUPPORTED
138 #define PNG_READ_gAMA_SUPPORTED
139 #define PNG_READ_hIST_SUPPORTED
140 #define PNG_READ_iCCP_SUPPORTED
141 #define PNG_READ_iTXt_SUPPORTED
142 #define PNG_READ_oFFs_SUPPORTED
143 #define PNG_READ_pCAL_SUPPORTED
144 #define PNG_READ_pHYs_SUPPORTED
145 #define PNG_READ_sBIT_SUPPORTED
146 #define PNG_READ_sCAL_SUPPORTED
147 #define PNG_READ_sPLT_SUPPORTED
148 #define PNG_READ_sRGB_SUPPORTED
149 #define PNG_READ_tEXt_SUPPORTED
150 #define PNG_READ_tIME_SUPPORTED
151 #define PNG_READ_tRNS_SUPPORTED
152 #define PNG_READ_zTXt_SUPPORTED
153 #define PNG_SAVE_INT_32_SUPPORTED
154 #define PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
155 #define PNG_SEQUENTIAL_READ_SUPPORTED
156 #define PNG_SET_CHUNK_CACHE_LIMIT_SUPPORTED
157 #define PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
158 #define PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
159 #define PNG_SET_USER_LIMITS_SUPPORTED
160 #define PNG_SIMPLIFIED_READ_AFIRST_SUPPORTED
161 #define PNG_SIMPLIFIED_READ_BGR_SUPPORTED
162 #define PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
163 #define PNG_SIMPLIFIED_WRITE_BGR_SUPPORTED
164 #define PNG_STDIO_SUPPORTED
165 #define PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
166 #define PNG_TEXT_SUPPORTED
167 #define PNG_TIME_RFC1123_SUPPORTED
168 #define PNG_UNKNOWN_CHUNKS_SUPPORTED
169 #define PNG_USER_CHUNKS_SUPPORTED
170 #define PNG_USER_LIMITS_SUPPORTED
171 #define PNG_USER_TRANSFORM_INFO_SUPPORTED
172 #define PNG_USER_TRANSFORM_PTR_SUPPORTED
173 #define PNG_WARNINGS_SUPPORTED
174 #define PNG_WRITE_16BIT_SUPPORTED
175 #define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
176 #define PNG_WRITE_BGR_SUPPORTED
177 #define PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
178 #define PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
179 #define PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
180 #define PNG_WRITE_FILLER_SUPPORTED
181 #define PNG_WRITE_FILTER_SUPPORTED
182 #define PNG_WRITE_FLUSH_SUPPORTED
183 #define PNG_WRITE_GET_PALETTE_MAX_SUPPORTED
184 #define PNG_WRITE_INTERLACING_SUPPORTED
185 #define PNG_WRITE_INT_FUNCTIONS_SUPPORTED
186 #define PNG_WRITE_INVERT_ALPHA_SUPPORTED
187 #define PNG_WRITE_INVERT_SUPPORTED
188 #define PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
189 #define PNG_WRITE_PACKSWAP_SUPPORTED
190 #define PNG_WRITE_PACK_SUPPORTED
191 #define PNG_WRITE_SHIFT_SUPPORTED
192 #define PNG_WRITE_SUPPORTED
193 #define PNG_WRITE_SWAP_ALPHA_SUPPORTED
194 #define PNG_WRITE_SWAP_SUPPORTED
195 #define PNG_WRITE_TEXT_SUPPORTED
196 #define PNG_WRITE_TRANSFORMS_SUPPORTED
197 #define PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
198 #define PNG_WRITE_USER_TRANSFORM_SUPPORTED
199 #define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
200 #define PNG_WRITE_bKGD_SUPPORTED
201 #define PNG_WRITE_cHRM_SUPPORTED
202 #define PNG_WRITE_gAMA_SUPPORTED
203 #define PNG_WRITE_hIST_SUPPORTED
204 #define PNG_WRITE_iCCP_SUPPORTED
205 #define PNG_WRITE_iTXt_SUPPORTED
206 #define PNG_WRITE_oFFs_SUPPORTED
207 #define PNG_WRITE_pCAL_SUPPORTED
208 #define PNG_WRITE_pHYs_SUPPORTED
209 #define PNG_WRITE_sBIT_SUPPORTED
210 #define PNG_WRITE_sCAL_SUPPORTED
211 #define PNG_WRITE_sPLT_SUPPORTED
212 #define PNG_WRITE_sRGB_SUPPORTED
213 #define PNG_WRITE_tEXt_SUPPORTED
214 #define PNG_WRITE_tIME_SUPPORTED
215 #define PNG_WRITE_tRNS_SUPPORTED
216 #define PNG_WRITE_zTXt_SUPPORTED
217 #define PNG_bKGD_SUPPORTED
218 #define PNG_cHRM_SUPPORTED
219 #define PNG_gAMA_SUPPORTED
220 #define PNG_hIST_SUPPORTED
221 #define PNG_iCCP_SUPPORTED
222 #define PNG_iTXt_SUPPORTED
223 #define PNG_oFFs_SUPPORTED
224 #define PNG_pCAL_SUPPORTED
225 #define PNG_pHYs_SUPPORTED
226 #define PNG_sBIT_SUPPORTED
227 #define PNG_sCAL_SUPPORTED
228 #define PNG_sPLT_SUPPORTED
229 #define PNG_sRGB_SUPPORTED
230 #define PNG_tEXt_SUPPORTED
231 #define PNG_tIME_SUPPORTED
232 #define PNG_tRNS_SUPPORTED
233 #define PNG_zTXt_SUPPORTED
234
235 #define PNG_STRING_COPYRIGHT "";
236 #define PNG_STRING_NEWLINE "\n"
237 #define PNG_LITERAL_SHARP 0x23
238 #define PNG_LITERAL_LEFT_SQUARE_BRACKET 0x5b
239 #define PNG_LITERAL_RIGHT_SQUARE_BRACKET 0x5d
240
241 #define PNG_API_RULE 0
242 #define PNG_CALLOC_SUPPORTED
243 #define PNG_COST_SHIFT 3
244 #define PNG_DEFAULT_READ_MACROS 1
245 #define PNG_GAMMA_THRESHOLD_FIXED 5000
246 #define PNG_IDAT_READ_SIZE PNG_ZBUF_SIZE
247 #define PNG_INFLATE_BUF_SIZE 1024
248 #define PNG_MAX_GAMMA_8 11
249 #define PNG_QUANTIZE_BLUE_BITS 5
250 #define PNG_QUANTIZE_GREEN_BITS 5
251 #define PNG_QUANTIZE_RED_BITS 5
252 #define PNG_TEXT_Z_DEFAULT_COMPRESSION (-1)
253 #define PNG_TEXT_Z_DEFAULT_STRATEGY 0
254 #define PNG_WEIGHT_SHIFT 8
255 #define PNG_ZBUF_SIZE 8192
256 #define PNG_Z_DEFAULT_COMPRESSION (-1)
257 #define PNG_Z_DEFAULT_NOFILTER_STRATEGY 0
258 #define PNG_Z_DEFAULT_STRATEGY 1
259 #define PNG_sCAL_PRECISION 5
260 #define PNG_sRGB_PROFILE_CHECKS 2
261
262 #define PNG_LINKAGE_API
263 #define PNG_LINKAGE_FUNCTION
264
265 #define PNG_ARM_NEON_OPT 0
266
267 #if ! defined (PNG_USER_WIDTH_MAX)
268 #define PNG_USER_WIDTH_MAX 1000000
269 #endif
270
271 #if ! defined (PNG_USER_HEIGHT_MAX)
272 #define PNG_USER_HEIGHT_MAX 1000000
273 #endif
274
275 #define png_debug(a, b)
276 #define png_debug1(a, b, c)
277 #define png_debug2(a, b, c, d)
278
279 #include "pnglib/png.h"
280 #include "pnglib/pngconf.h"
281
282 #define PNG_NO_EXTERN
283 #include "pnglib/png.c"
284 #include "pnglib/pngerror.c"
285 #include "pnglib/pngget.c"
286 #include "pnglib/pngmem.c"
287 #include "pnglib/pngread.c"
288 #include "pnglib/pngpread.c"
289 #include "pnglib/pngrio.c"
290
291 void png_do_expand_palette (png_row_infop, png_bytep, png_const_colorp, png_const_bytep, int);
292 void png_do_expand (png_row_infop, png_bytep, png_const_color_16p);
293 void png_do_chop (png_row_infop, png_bytep);
294 void png_do_quantize (png_row_infop, png_bytep, png_const_bytep, png_const_bytep);
295 void png_do_gray_to_rgb (png_row_infop, png_bytep);
296 void png_do_unshift (png_row_infop, png_bytep, png_const_color_8p);
297 void png_do_unpack (png_row_infop, png_bytep);
298 int png_do_rgb_to_gray (png_structrp, png_row_infop, png_bytep);
299 void png_do_compose (png_row_infop, png_bytep, png_structrp);
300 void png_do_gamma (png_row_infop, png_bytep, png_structrp);
301 void png_do_encode_alpha (png_row_infop, png_bytep, png_structrp);
302 void png_do_scale_16_to_8 (png_row_infop, png_bytep);
303 void png_do_expand_16 (png_row_infop, png_bytep);
304 void png_do_read_filler (png_row_infop, png_bytep, png_uint_32, png_uint_32);
305 void png_do_read_invert_alpha (png_row_infop, png_bytep);
306 void png_do_read_swap_alpha (png_row_infop, png_bytep);
307
308 #include "pnglib/pngrtran.c"
309 #include "pnglib/pngrutil.c"
310 #include "pnglib/pngset.c"
311 #include "pnglib/pngtrans.c"
312 #include "pnglib/pngwio.c"
313 #include "pnglib/pngwrite.c"
314 #include "pnglib/pngwtran.c"
315 #include "pnglib/pngwutil.c"
316
317 JUCE_END_IGNORE_WARNINGS_GCC_LIKE
318
319 #else
320 extern "C"
321 {
322 #include <png.h>
323 #include <pngconf.h>
324 }
325 #endif
326 }
327
328 #undef max
329 #undef min
330 #undef fdopen
331
332 JUCE_END_IGNORE_WARNINGS_MSVC
333
334 //==============================================================================
335 namespace PNGHelpers
336 {
337 using namespace pnglibNamespace;
338
writeDataCallback(png_structp png,png_bytep data,png_size_t length)339 static void JUCE_CDECL writeDataCallback (png_structp png, png_bytep data, png_size_t length)
340 {
341 static_cast<OutputStream*> (png_get_io_ptr (png))->write (data, length);
342 }
343
344 #if ! JUCE_USING_COREIMAGE_LOADER
readCallback(png_structp png,png_bytep data,png_size_t length)345 static void JUCE_CDECL readCallback (png_structp png, png_bytep data, png_size_t length)
346 {
347 static_cast<InputStream*> (png_get_io_ptr (png))->read (data, (int) length);
348 }
349
350 struct PNGErrorStruct {};
351
errorCallback(png_structp p,png_const_charp)352 static void JUCE_CDECL errorCallback (png_structp p, png_const_charp)
353 {
354 #ifdef PNG_SETJMP_SUPPORTED
355 setjmp(png_jmpbuf(p));
356 #else
357 longjmp (*(jmp_buf*) p->error_ptr, 1);
358 #endif
359 }
360
warningCallback(png_structp,png_const_charp)361 static void JUCE_CDECL warningCallback (png_structp, png_const_charp) {}
362
363 JUCE_BEGIN_IGNORE_WARNINGS_MSVC (4611)
364
readHeader(InputStream & in,png_structp pngReadStruct,png_infop pngInfoStruct,jmp_buf & errorJumpBuf,png_uint_32 & width,png_uint_32 & height,int & bitDepth,int & colorType,int & interlaceType)365 static bool readHeader (InputStream& in, png_structp pngReadStruct, png_infop pngInfoStruct, jmp_buf& errorJumpBuf,
366 png_uint_32& width, png_uint_32& height, int& bitDepth, int& colorType, int& interlaceType) noexcept
367 {
368 if (setjmp (errorJumpBuf) == 0)
369 {
370 // read the header..
371 png_set_read_fn (pngReadStruct, &in, readCallback);
372
373 png_read_info (pngReadStruct, pngInfoStruct);
374
375 png_get_IHDR (pngReadStruct, pngInfoStruct,
376 &width, &height,
377 &bitDepth, &colorType,
378 &interlaceType, nullptr, nullptr);
379
380 if (bitDepth == 16)
381 png_set_strip_16 (pngReadStruct);
382
383 if (colorType == PNG_COLOR_TYPE_PALETTE)
384 png_set_expand (pngReadStruct);
385
386 if (bitDepth < 8)
387 png_set_expand (pngReadStruct);
388
389 if (colorType == PNG_COLOR_TYPE_GRAY || colorType == PNG_COLOR_TYPE_GRAY_ALPHA)
390 png_set_gray_to_rgb (pngReadStruct);
391
392 return true;
393 }
394
395 return false;
396 }
397
readImageData(png_structp pngReadStruct,png_infop pngInfoStruct,jmp_buf & errorJumpBuf,png_bytepp rows)398 static bool readImageData (png_structp pngReadStruct, png_infop pngInfoStruct, jmp_buf& errorJumpBuf, png_bytepp rows) noexcept
399 {
400 if (setjmp (errorJumpBuf) == 0)
401 {
402 if (png_get_valid (pngReadStruct, pngInfoStruct, PNG_INFO_tRNS))
403 png_set_expand (pngReadStruct);
404
405 png_set_add_alpha (pngReadStruct, 0xff, PNG_FILLER_AFTER);
406
407 png_read_image (pngReadStruct, rows);
408 png_read_end (pngReadStruct, pngInfoStruct);
409 return true;
410 }
411
412 return false;
413 }
414
415 JUCE_END_IGNORE_WARNINGS_MSVC
416
createImageFromData(bool hasAlphaChan,int width,int height,png_bytepp rows)417 static Image createImageFromData (bool hasAlphaChan, int width, int height, png_bytepp rows)
418 {
419 // now convert the data to a juce image format..
420 Image image (hasAlphaChan ? Image::ARGB : Image::RGB, width, height, hasAlphaChan);
421
422 image.getProperties()->set ("originalImageHadAlpha", image.hasAlphaChannel());
423 hasAlphaChan = image.hasAlphaChannel(); // (the native image creator may not give back what we expect)
424
425 const Image::BitmapData destData (image, Image::BitmapData::writeOnly);
426
427 for (int y = 0; y < (int) height; ++y)
428 {
429 const uint8* src = rows[y];
430 uint8* dest = destData.getLinePointer (y);
431
432 if (hasAlphaChan)
433 {
434 for (int i = (int) width; --i >= 0;)
435 {
436 ((PixelARGB*) dest)->setARGB (src[3], src[0], src[1], src[2]);
437 ((PixelARGB*) dest)->premultiply();
438 dest += destData.pixelStride;
439 src += 4;
440 }
441 }
442 else
443 {
444 for (int i = (int) width; --i >= 0;)
445 {
446 ((PixelRGB*) dest)->setARGB (0, src[0], src[1], src[2]);
447 dest += destData.pixelStride;
448 src += 4;
449 }
450 }
451 }
452
453 return image;
454 }
455
readImage(InputStream & in,png_structp pngReadStruct,png_infop pngInfoStruct)456 static Image readImage (InputStream& in, png_structp pngReadStruct, png_infop pngInfoStruct)
457 {
458 jmp_buf errorJumpBuf;
459 png_set_error_fn (pngReadStruct, &errorJumpBuf, errorCallback, warningCallback);
460
461 png_uint_32 width = 0, height = 0;
462 int bitDepth = 0, colorType = 0, interlaceType = 0;
463
464 if (readHeader (in, pngReadStruct, pngInfoStruct, errorJumpBuf,
465 width, height, bitDepth, colorType, interlaceType))
466 {
467 // Load the image into a temp buffer..
468 const size_t lineStride = width * 4;
469 HeapBlock<uint8> tempBuffer (height * lineStride);
470 HeapBlock<png_bytep> rows (height);
471
472 for (size_t y = 0; y < height; ++y)
473 rows[y] = (png_bytep) (tempBuffer + lineStride * y);
474
475 png_bytep trans_alpha = nullptr;
476 png_color_16p trans_color = nullptr;
477 int num_trans = 0;
478 png_get_tRNS (pngReadStruct, pngInfoStruct, &trans_alpha, &num_trans, &trans_color);
479
480 if (readImageData (pngReadStruct, pngInfoStruct, errorJumpBuf, rows))
481 return createImageFromData ((colorType & PNG_COLOR_MASK_ALPHA) != 0 || num_trans != 0,
482 (int) width, (int) height, rows);
483 }
484
485 return Image();
486 }
487
readImage(InputStream & in)488 static Image readImage (InputStream& in)
489 {
490 if (png_structp pngReadStruct = png_create_read_struct (PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr))
491 {
492 if (png_infop pngInfoStruct = png_create_info_struct (pngReadStruct))
493 {
494 Image image (readImage (in, pngReadStruct, pngInfoStruct));
495 png_destroy_read_struct (&pngReadStruct, &pngInfoStruct, nullptr);
496 return image;
497 }
498
499 png_destroy_read_struct (&pngReadStruct, nullptr, nullptr);
500 }
501
502 return Image();
503 }
504 #endif
505 }
506
507 //==============================================================================
PNGImageFormat()508 PNGImageFormat::PNGImageFormat() {}
~PNGImageFormat()509 PNGImageFormat::~PNGImageFormat() {}
510
getFormatName()511 String PNGImageFormat::getFormatName() { return "PNG"; }
usesFileExtension(const File & f)512 bool PNGImageFormat::usesFileExtension (const File& f) { return f.hasFileExtension ("png"); }
513
canUnderstand(InputStream & in)514 bool PNGImageFormat::canUnderstand (InputStream& in)
515 {
516 const int bytesNeeded = 4;
517 char header [bytesNeeded];
518
519 return in.read (header, bytesNeeded) == bytesNeeded
520 && header[1] == 'P'
521 && header[2] == 'N'
522 && header[3] == 'G';
523 }
524
525 #if JUCE_USING_COREIMAGE_LOADER
526 Image juce_loadWithCoreImage (InputStream&);
527 #endif
528
decodeImage(InputStream & in)529 Image PNGImageFormat::decodeImage (InputStream& in)
530 {
531 #if JUCE_USING_COREIMAGE_LOADER
532 return juce_loadWithCoreImage (in);
533 #else
534 return PNGHelpers::readImage (in);
535 #endif
536 }
537
writeImageToStream(const Image & image,OutputStream & out)538 bool PNGImageFormat::writeImageToStream (const Image& image, OutputStream& out)
539 {
540 using namespace pnglibNamespace;
541 auto width = image.getWidth();
542 auto height = image.getHeight();
543
544 auto pngWriteStruct = png_create_write_struct (PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
545
546 if (pngWriteStruct == nullptr)
547 return false;
548
549 auto pngInfoStruct = png_create_info_struct (pngWriteStruct);
550
551 if (pngInfoStruct == nullptr)
552 {
553 png_destroy_write_struct (&pngWriteStruct, nullptr);
554 return false;
555 }
556
557 png_set_write_fn (pngWriteStruct, &out, PNGHelpers::writeDataCallback, nullptr);
558
559 png_set_IHDR (pngWriteStruct, pngInfoStruct, (png_uint_32) width, (png_uint_32) height, 8,
560 image.hasAlphaChannel() ? PNG_COLOR_TYPE_RGB_ALPHA
561 : PNG_COLOR_TYPE_RGB,
562 PNG_INTERLACE_NONE,
563 PNG_COMPRESSION_TYPE_BASE,
564 PNG_FILTER_TYPE_BASE);
565
566 HeapBlock<uint8> rowData (width * 4);
567
568 png_color_8 sig_bit;
569 sig_bit.red = 8;
570 sig_bit.green = 8;
571 sig_bit.blue = 8;
572 sig_bit.gray = 0;
573 sig_bit.alpha = 8;
574 png_set_sBIT (pngWriteStruct, pngInfoStruct, &sig_bit);
575
576 png_write_info (pngWriteStruct, pngInfoStruct);
577
578 png_set_shift (pngWriteStruct, &sig_bit);
579 png_set_packing (pngWriteStruct);
580
581 const Image::BitmapData srcData (image, Image::BitmapData::readOnly);
582
583 for (int y = 0; y < height; ++y)
584 {
585 uint8* dst = rowData;
586 const uint8* src = srcData.getLinePointer (y);
587
588 if (image.hasAlphaChannel())
589 {
590 for (int i = width; --i >= 0;)
591 {
592 PixelARGB p (*(const PixelARGB*) src);
593 p.unpremultiply();
594
595 *dst++ = p.getRed();
596 *dst++ = p.getGreen();
597 *dst++ = p.getBlue();
598 *dst++ = p.getAlpha();
599 src += srcData.pixelStride;
600 }
601 }
602 else
603 {
604 for (int i = width; --i >= 0;)
605 {
606 *dst++ = ((const PixelRGB*) src)->getRed();
607 *dst++ = ((const PixelRGB*) src)->getGreen();
608 *dst++ = ((const PixelRGB*) src)->getBlue();
609 src += srcData.pixelStride;
610 }
611 }
612
613 png_bytep rowPtr = rowData;
614 png_write_rows (pngWriteStruct, &rowPtr, 1);
615 }
616
617 png_write_end (pngWriteStruct, pngInfoStruct);
618 png_destroy_write_struct (&pngWriteStruct, &pngInfoStruct);
619
620 return true;
621 }
622
623 } // namespace juce
624