This repository has been archived by the owner on Jun 12, 2022. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 38
/
stb_image.c
4940 lines (4388 loc) · 155 KB
/
stb_image.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* stbi-1.28 - public domain JPEG/PNG reader - http://nothings.org/stb_image.c
when you control the images you're loading
no warranty implied; use at your own risk
QUICK NOTES:
Primarily of interest to game developers and other people who can
avoid problematic images and only need the trivial interface
JPEG baseline (no JPEG progressive)
PNG 8-bit only
TGA (not sure what subset, if a subset)
BMP non-1bpp, non-RLE
PSD (composited view only, no extra channels)
GIF (*comp always reports as 4-channel)
HDR (radiance rgbE format)
PIC (Softimage PIC)
- decoded from memory or through stdio FILE (define STBI_NO_STDIO to remove code)
- supports installable dequantizing-IDCT, YCbCr-to-RGB conversion (define STBI_SIMD)
Latest revisions:
1.28 (2010-08-01) fix bug in GIF palette transparency (SpartanJ)
1.27 (2010-08-01) cast-to-uint8 to fix warnings (Laurent Gomila)
allow trailing 0s at end of image data (Laurent Gomila)
1.26 (2010-07-24) fix bug in file buffering for PNG reported by SpartanJ
1.25 (2010-07-17) refix trans_data warning (Won Chun)
1.24 (2010-07-12) perf improvements reading from files
minor perf improvements for jpeg
deprecated type-specific functions in hope of feedback
attempt to fix trans_data warning (Won Chun)
1.23 fixed bug in iPhone support
1.22 (2010-07-10) removed image *writing* support to stb_image_write.h
stbi_info support from Jetro Lauha
GIF support from Jean-Marc Lienher
iPhone PNG-extensions from James Brown
warning-fixes from Nicolas Schulz and Janez Zemva
1.21 fix use of 'uint8' in header (reported by jon blow)
1.20 added support for Softimage PIC, by Tom Seddon
See end of file for full revision history.
TODO:
stbi_info support for BMP,PSD,HDR,PIC
rewrite stbi_info and load_file variations to share file handling code
(current system allows individual functions to be called directly,
since each does all the work, but I doubt anyone uses this in practice)
============================ Contributors =========================
Image formats Optimizations & bugfixes
Sean Barrett (jpeg, png, bmp) Fabian "ryg" Giesen
Nicolas Schulz (hdr, psd)
Jonathan Dummer (tga) Bug fixes & warning fixes
Jean-Marc Lienher (gif) Marc LeBlanc
Tom Seddon (pic) Christpher Lloyd
Thatcher Ulrich (psd) Dave Moore
Won Chun
the Horde3D community
Extensions, features Janez Zemva
Jetro Lauha (stbi_info) Jonathan Blow
James "moose2000" Brown (iPhone PNG) Laurent Gomila
If your name should be here but isn't, let Sean know.
*/
#ifndef STBI_INCLUDE_STB_IMAGE_H
#define STBI_INCLUDE_STB_IMAGE_H
// To get a header file for this, either cut and paste the header,
// or create stb_image.h, #define STBI_HEADER_FILE_ONLY, and
// then include stb_image.c from it.
//// begin header file ////////////////////////////////////////////////////
//
// Limitations:
// - no jpeg progressive support
// - non-HDR formats support 8-bit samples only (jpeg, png)
// - no delayed line count (jpeg) -- IJG doesn't support either
// - no 1-bit BMP
// - GIF always returns *comp=4
//
// Basic usage (see HDR discussion below):
// int x,y,n;
// unsigned char *data = stbi_load(filename, &x, &y, &n, 0);
// // ... process data if not NULL ...
// // ... x = width, y = height, n = # 8-bit components per pixel ...
// // ... replace '0' with '1'..'4' to force that many components per pixel
// stbi_image_free(data)
//
// Standard parameters:
// int *x -- outputs image width in pixels
// int *y -- outputs image height in pixels
// int *comp -- outputs # of image components in image file
// int req_comp -- if non-zero, # of image components requested in result
//
// The return value from an image loader is an 'unsigned char *' which points
// to the pixel data. The pixel data consists of *y scanlines of *x pixels,
// with each pixel consisting of N interleaved 8-bit components; the first
// pixel pointed to is top-left-most in the image. There is no padding between
// image scanlines or between pixels, regardless of format. The number of
// components N is 'req_comp' if req_comp is non-zero, or *comp otherwise.
// If req_comp is non-zero, *comp has the number of components that _would_
// have been output otherwise. E.g. if you set req_comp to 4, you will always
// get RGBA output, but you can check *comp to easily see if it's opaque.
//
// An output image with N components has the following components interleaved
// in this order in each pixel:
//
// N=#comp components
// 1 grey
// 2 grey, alpha
// 3 red, green, blue
// 4 red, green, blue, alpha
//
// If image loading fails for any reason, the return value will be NULL,
// and *x, *y, *comp will be unchanged. The function stbi_failure_reason()
// can be queried for an extremely brief, end-user unfriendly explanation
// of why the load failed. Define STBI_NO_FAILURE_STRINGS to avoid
// compiling these strings at all, and STBI_FAILURE_USERMSG to get slightly
// more user-friendly ones.
//
// Paletted PNG, BMP, GIF, and PIC images are automatically depalettized.
//
// ===========================================================================
//
// iPhone PNG support:
//
// By default we convert iphone-formatted PNGs back to RGB; nominally they
// would silently load as BGR, except the existing code should have just
// failed on such iPhone PNGs. But you can disable this conversion by
// by calling stbi_convert_iphone_png_to_rgb(0), in which case
// you will always just get the native iphone "format" through.
//
// Call stbi_set_unpremultiply_on_load(1) as well to force a divide per
// pixel to remove any premultiplied alpha *only* if the image file explicitly
// says there's premultiplied data (currently only happens in iPhone images,
// and only if iPhone convert-to-rgb processing is on).
//
// ===========================================================================
//
// HDR image support (disable by defining STBI_NO_HDR)
//
// stb_image now supports loading HDR images in general, and currently
// the Radiance .HDR file format, although the support is provided
// generically. You can still load any file through the existing interface;
// if you attempt to load an HDR file, it will be automatically remapped to
// LDR, assuming gamma 2.2 and an arbitrary scale factor defaulting to 1;
// both of these constants can be reconfigured through this interface:
//
// stbi_hdr_to_ldr_gamma(2.2f);
// stbi_hdr_to_ldr_scale(1.0f);
//
// (note, do not use _inverse_ constants; stbi_image will invert them
// appropriately).
//
// Additionally, there is a new, parallel interface for loading files as
// (linear) floats to preserve the full dynamic range:
//
// float *data = stbi_loadf(filename, &x, &y, &n, 0);
//
// If you load LDR images through this interface, those images will
// be promoted to floating point values, run through the inverse of
// constants corresponding to the above:
//
// stbi_ldr_to_hdr_scale(1.0f);
// stbi_ldr_to_hdr_gamma(2.2f);
//
// Finally, given a filename (or an open file or memory block--see header
// file for details) containing image data, you can query for the "most
// appropriate" interface to use (that is, whether the image is HDR or
// not), using:
//
// stbi_is_hdr(char *filename);
#ifndef STBI_NO_STDIO
#include <stdio.h>
#endif
#define STBI_VERSION 1
enum
{
STBI_default = 0, // only used for req_comp
STBI_grey = 1,
STBI_grey_alpha = 2,
STBI_rgb = 3,
STBI_rgb_alpha = 4,
};
typedef unsigned char stbi_uc;
#ifdef __cplusplus
extern "C" {
#endif
// PRIMARY API - works on images of any type
// load image by filename, open file, or memory buffer
extern stbi_uc *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern stbi_uc *stbi_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
// for stbi_load_from_file, file pointer is left pointing immediately after image
#endif
#ifndef STBI_NO_HDR
extern float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern float *stbi_loadf (char const *filename, int *x, int *y, int *comp, int req_comp);
extern float *stbi_loadf_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
extern void stbi_hdr_to_ldr_gamma(float gamma);
extern void stbi_hdr_to_ldr_scale(float scale);
extern void stbi_ldr_to_hdr_gamma(float gamma);
extern void stbi_ldr_to_hdr_scale(float scale);
#endif // STBI_NO_HDR
// get a VERY brief reason for failure
// NOT THREADSAFE
extern const char *stbi_failure_reason (void);
// free the loaded image -- this is just free()
extern void stbi_image_free (void *retval_from_stbi_load);
// get image dimensions & components without fully decoding
extern int stbi_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
extern int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len);
#ifndef STBI_NO_STDIO
extern int stbi_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_info_from_file (FILE *f, int *x, int *y, int *comp);
extern int stbi_is_hdr (char const *filename);
extern int stbi_is_hdr_from_file(FILE *f);
#endif
// for image formats that explicitly notate that they have premultiplied alpha,
// we just return the colors as stored in the file. set this flag to force
// unpremultiplication. results are undefined if the unpremultiply overflow.
extern void stbi_set_unpremultiply_on_load(int flag_true_if_should_unpremultiply);
// indicate whether we should process iphone images back to canonical format,
// or just pass them through "as-is"
extern void stbi_convert_iphone_png_to_rgb(int flag_true_if_should_convert);
// ZLIB client - used by PNG, available for other purposes
extern char *stbi_zlib_decode_malloc_guesssize(const char *buffer, int len, int initial_size, int *outlen);
extern char *stbi_zlib_decode_malloc(const char *buffer, int len, int *outlen);
extern int stbi_zlib_decode_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
extern char *stbi_zlib_decode_noheader_malloc(const char *buffer, int len, int *outlen);
extern int stbi_zlib_decode_noheader_buffer(char *obuffer, int olen, const char *ibuffer, int ilen);
// define new loaders
typedef struct
{
int (*test_memory)(stbi_uc const *buffer, int len);
stbi_uc * (*load_from_memory)(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
int (*test_file)(FILE *f);
stbi_uc * (*load_from_file)(FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
} stbi_loader;
// register a loader by filling out the above structure (you must define ALL functions)
// returns 1 if added or already added, 0 if not added (too many loaders)
// NOT THREADSAFE
extern int stbi_register_loader(stbi_loader *loader);
// define faster low-level operations (typically SIMD support)
#if STBI_SIMD
typedef void (*stbi_idct_8x8)(stbi_uc *out, int out_stride, short data[64], unsigned short *dequantize);
// compute an integer IDCT on "input"
// input[x] = data[x] * dequantize[x]
// write results to 'out': 64 samples, each run of 8 spaced by 'out_stride'
// CLAMP results to 0..255
typedef void (*stbi_YCbCr_to_RGB_run)(stbi_uc *output, stbi_uc const *y, stbi_uc const *cb, stbi_uc const *cr, int count, int step);
// compute a conversion from YCbCr to RGB
// 'count' pixels
// write pixels to 'output'; each pixel is 'step' bytes (either 3 or 4; if 4, write '255' as 4th), order R,G,B
// y: Y input channel
// cb: Cb input channel; scale/biased to be 0..255
// cr: Cr input channel; scale/biased to be 0..255
extern void stbi_install_idct(stbi_idct_8x8 func);
extern void stbi_install_YCbCr_to_RGB(stbi_YCbCr_to_RGB_run func);
#endif // STBI_SIMD
// TYPE-SPECIFIC ACCESS
#ifdef STBI_TYPE_SPECIFIC_FUNCTIONS
// is it a jpeg?
extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
#ifndef STBI_NO_STDIO
extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern int stbi_jpeg_test_file (FILE *f);
extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp);
#endif
// is it a png?
extern int stbi_png_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp);
#ifndef STBI_NO_STDIO
extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern int stbi_png_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_png_test_file (FILE *f);
extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp);
#endif
// is it a bmp?
extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_bmp_test_file (FILE *f);
extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a tga?
extern int stbi_tga_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_tga_test_file (FILE *f);
extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a psd?
extern int stbi_psd_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_psd_test_file (FILE *f);
extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it an hdr?
extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len);
extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_hdr_test_file (FILE *f);
extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a pic?
extern int stbi_pic_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_pic_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_pic_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_pic_test_file (FILE *f);
extern stbi_uc *stbi_pic_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a gif?
extern int stbi_gif_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
extern int stbi_gif_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp);
#ifndef STBI_NO_STDIO
extern int stbi_gif_test_file (FILE *f);
extern stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
extern int stbi_gif_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_gif_info_from_file (FILE *f, int *x, int *y, int *comp);
#endif
#endif//STBI_TYPE_SPECIFIC_FUNCTIONS
#ifdef __cplusplus
}
#endif
//
//
//// end header file /////////////////////////////////////////////////////
#endif // STBI_INCLUDE_STB_IMAGE_H
#ifndef STBI_HEADER_FILE_ONLY
#ifndef STBI_NO_HDR
#include <math.h> // ldexp
#include <string.h> // strcmp
#endif
#ifndef STBI_NO_STDIO
#include <stdio.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <malloc.h>
//#include <memory.h>
#include <assert.h>
#include <stdarg.h>
#ifndef _MSC_VER
#ifdef __cplusplus
#define __forceinline inline
#else
#define __forceinline
#endif
#endif
// implementation:
typedef unsigned char uint8;
typedef unsigned short uint16;
typedef signed short int16;
typedef unsigned int uint32;
typedef signed int int32;
typedef unsigned int uint;
// should produce compiler error if size is wrong
typedef unsigned char validate_uint32[sizeof(uint32)==4 ? 1 : -1];
#if defined(STBI_NO_STDIO) && !defined(STBI_NO_WRITE)
#define STBI_NO_WRITE
#endif
#define STBI_NOTUSED(v) v=v
#ifdef _MSC_VER
#define STBI_HAS_LRTOL
#endif
#ifdef STBI_HAS_LRTOL
#define stbi_lrot(x,y) _lrotl(x,y)
#else
#define stbi_lrot(x,y) (((x) << (y)) | ((x) >> (32 - (y))))
#endif
//////////////////////////////////////////////////////////////////////////////
//
// Generic API that works on all image types
//
// deprecated functions
// is it a jpeg?
extern int stbi_jpeg_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_jpeg_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
extern int stbi_jpeg_info_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp);
#ifndef STBI_NO_STDIO
extern stbi_uc *stbi_jpeg_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern int stbi_jpeg_test_file (FILE *f);
extern stbi_uc *stbi_jpeg_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
extern int stbi_jpeg_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_jpeg_info_from_file (FILE *f, int *x, int *y, int *comp);
#endif
// is it a png?
extern int stbi_png_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_png_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
extern int stbi_png_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp);
#ifndef STBI_NO_STDIO
extern stbi_uc *stbi_png_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern int stbi_png_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_png_test_file (FILE *f);
extern stbi_uc *stbi_png_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
extern int stbi_png_info_from_file (FILE *f, int *x, int *y, int *comp);
#endif
// is it a bmp?
extern int stbi_bmp_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_bmp_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_bmp_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_bmp_test_file (FILE *f);
extern stbi_uc *stbi_bmp_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a tga?
extern int stbi_tga_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_tga_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_tga_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_tga_test_file (FILE *f);
extern stbi_uc *stbi_tga_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a psd?
extern int stbi_psd_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_psd_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_psd_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_psd_test_file (FILE *f);
extern stbi_uc *stbi_psd_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it an hdr?
extern int stbi_hdr_test_memory (stbi_uc const *buffer, int len);
extern float * stbi_hdr_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern float * stbi_hdr_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_hdr_test_file (FILE *f);
extern float * stbi_hdr_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a pic?
extern int stbi_pic_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_pic_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_pic_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
#ifndef STBI_NO_STDIO
extern int stbi_pic_test_file (FILE *f);
extern stbi_uc *stbi_pic_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
#endif
// is it a gif?
extern int stbi_gif_test_memory (stbi_uc const *buffer, int len);
extern stbi_uc *stbi_gif_load (char const *filename, int *x, int *y, int *comp, int req_comp);
extern stbi_uc *stbi_gif_load_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp);
extern int stbi_gif_info_from_memory (stbi_uc const *buffer, int len, int *x, int *y, int *comp);
#ifndef STBI_NO_STDIO
extern int stbi_gif_test_file (FILE *f);
extern stbi_uc *stbi_gif_load_from_file (FILE *f, int *x, int *y, int *comp, int req_comp);
extern int stbi_gif_info (char const *filename, int *x, int *y, int *comp);
extern int stbi_gif_info_from_file (FILE *f, int *x, int *y, int *comp);
#endif
// this is not threadsafe
static const char *failure_reason;
const char *stbi_failure_reason(void)
{
return failure_reason;
}
static int e(const char *str)
{
failure_reason = str;
return 0;
}
#ifdef STBI_NO_FAILURE_STRINGS
#define e(x,y) 0
#elif defined(STBI_FAILURE_USERMSG)
#define e(x,y) e(y)
#else
#define e(x,y) e(x)
#endif
#define epf(x,y) ((float *) (e(x,y)?NULL:NULL))
#define epuc(x,y) ((unsigned char *) (e(x,y)?NULL:NULL))
void stbi_image_free(void *retval_from_stbi_load)
{
free(retval_from_stbi_load);
}
#define MAX_LOADERS 32
stbi_loader *loaders[MAX_LOADERS];
static int max_loaders = 0;
int stbi_register_loader(stbi_loader *loader)
{
int i;
for (i=0; i < MAX_LOADERS; ++i) {
// already present?
if (loaders[i] == loader)
return 1;
// end of the list?
if (loaders[i] == NULL) {
loaders[i] = loader;
max_loaders = i+1;
return 1;
}
}
// no room for it
return 0;
}
#ifndef STBI_NO_HDR
static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp);
static stbi_uc *hdr_to_ldr(float *data, int x, int y, int comp);
#endif
#ifndef STBI_NO_STDIO
unsigned char *stbi_load(char const *filename, int *x, int *y, int *comp, int req_comp)
{
FILE *f = fopen(filename, "rb");
unsigned char *result;
if (!f) return epuc("can't fopen", "Unable to open file");
result = stbi_load_from_file(f,x,y,comp,req_comp);
fclose(f);
return result;
}
unsigned char *stbi_load_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
{
int i;
if (stbi_jpeg_test_file(f)) return stbi_jpeg_load_from_file(f,x,y,comp,req_comp);
if (stbi_png_test_file(f)) return stbi_png_load_from_file(f,x,y,comp,req_comp);
if (stbi_bmp_test_file(f)) return stbi_bmp_load_from_file(f,x,y,comp,req_comp);
if (stbi_gif_test_file(f)) return stbi_gif_load_from_file(f,x,y,comp,req_comp);
if (stbi_psd_test_file(f)) return stbi_psd_load_from_file(f,x,y,comp,req_comp);
if (stbi_pic_test_file(f)) return stbi_pic_load_from_file(f,x,y,comp,req_comp);
#ifndef STBI_NO_HDR
if (stbi_hdr_test_file(f)) {
float *hdr = stbi_hdr_load_from_file(f, x,y,comp,req_comp);
return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
}
#endif
for (i=0; i < max_loaders; ++i)
if (loaders[i]->test_file(f))
return loaders[i]->load_from_file(f,x,y,comp,req_comp);
// test tga last because it's a crappy test!
if (stbi_tga_test_file(f))
return stbi_tga_load_from_file(f,x,y,comp,req_comp);
return epuc("unknown image type", "Image not of any known type, or corrupt");
}
#endif
unsigned char *stbi_load_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
{
int i;
if (stbi_jpeg_test_memory(buffer,len)) return stbi_jpeg_load_from_memory(buffer,len,x,y,comp,req_comp);
if (stbi_png_test_memory(buffer,len)) return stbi_png_load_from_memory(buffer,len,x,y,comp,req_comp);
if (stbi_bmp_test_memory(buffer,len)) return stbi_bmp_load_from_memory(buffer,len,x,y,comp,req_comp);
if (stbi_gif_test_memory(buffer,len)) return stbi_gif_load_from_memory(buffer,len,x,y,comp,req_comp);
if (stbi_psd_test_memory(buffer,len)) return stbi_psd_load_from_memory(buffer,len,x,y,comp,req_comp);
if (stbi_pic_test_memory(buffer,len)) return stbi_pic_load_from_memory(buffer,len,x,y,comp,req_comp);
#ifndef STBI_NO_HDR
if (stbi_hdr_test_memory(buffer, len)) {
float *hdr = stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp);
return hdr_to_ldr(hdr, *x, *y, req_comp ? req_comp : *comp);
}
#endif
for (i=0; i < max_loaders; ++i)
if (loaders[i]->test_memory(buffer,len))
return loaders[i]->load_from_memory(buffer,len,x,y,comp,req_comp);
// test tga last because it's a crappy test!
if (stbi_tga_test_memory(buffer,len))
return stbi_tga_load_from_memory(buffer,len,x,y,comp,req_comp);
return epuc("unknown image type", "Image not of any known type, or corrupt");
}
#ifndef STBI_NO_HDR
#ifndef STBI_NO_STDIO
float *stbi_loadf(char const *filename, int *x, int *y, int *comp, int req_comp)
{
FILE *f = fopen(filename, "rb");
float *result;
if (!f) return epf("can't fopen", "Unable to open file");
result = stbi_loadf_from_file(f,x,y,comp,req_comp);
fclose(f);
return result;
}
float *stbi_loadf_from_file(FILE *f, int *x, int *y, int *comp, int req_comp)
{
unsigned char *data;
#ifndef STBI_NO_HDR
if (stbi_hdr_test_file(f))
return stbi_hdr_load_from_file(f,x,y,comp,req_comp);
#endif
data = stbi_load_from_file(f, x, y, comp, req_comp);
if (data)
return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
return epf("unknown image type", "Image not of any known type, or corrupt");
}
#endif
float *stbi_loadf_from_memory(stbi_uc const *buffer, int len, int *x, int *y, int *comp, int req_comp)
{
stbi_uc *data;
#ifndef STBI_NO_HDR
if (stbi_hdr_test_memory(buffer, len))
return stbi_hdr_load_from_memory(buffer, len,x,y,comp,req_comp);
#endif
data = stbi_load_from_memory(buffer, len, x, y, comp, req_comp);
if (data)
return ldr_to_hdr(data, *x, *y, req_comp ? req_comp : *comp);
return epf("unknown image type", "Image not of any known type, or corrupt");
}
#endif
// these is-hdr-or-not is defined independent of whether STBI_NO_HDR is
// defined, for API simplicity; if STBI_NO_HDR is defined, it always
// reports false!
int stbi_is_hdr_from_memory(stbi_uc const *buffer, int len)
{
#ifndef STBI_NO_HDR
return stbi_hdr_test_memory(buffer, len);
#else
return 0;
#endif
}
#ifndef STBI_NO_STDIO
extern int stbi_is_hdr (char const *filename)
{
FILE *f = fopen(filename, "rb");
int result=0;
if (f) {
result = stbi_is_hdr_from_file(f);
fclose(f);
}
return result;
}
extern int stbi_is_hdr_from_file(FILE *f)
{
#ifndef STBI_NO_HDR
return stbi_hdr_test_file(f);
#else
return 0;
#endif
}
#endif
#ifndef STBI_NO_HDR
static float h2l_gamma_i=1.0f/2.2f, h2l_scale_i=1.0f;
static float l2h_gamma=2.2f, l2h_scale=1.0f;
void stbi_hdr_to_ldr_gamma(float gamma) { h2l_gamma_i = 1/gamma; }
void stbi_hdr_to_ldr_scale(float scale) { h2l_scale_i = 1/scale; }
void stbi_ldr_to_hdr_gamma(float gamma) { l2h_gamma = gamma; }
void stbi_ldr_to_hdr_scale(float scale) { l2h_scale = scale; }
#endif
//////////////////////////////////////////////////////////////////////////////
//
// Common code used by all image loaders
//
enum
{
SCAN_load=0,
SCAN_type,
SCAN_header,
};
typedef struct
{
uint32 img_x, img_y;
int img_n, img_out_n;
#ifndef STBI_NO_STDIO
FILE *img_file;
int buflen;
uint8 buffer_start[128];
int from_file;
#endif
uint8 *img_buffer, *img_buffer_end;
} stbi;
#ifndef STBI_NO_STDIO
static void start_file(stbi *s, FILE *f)
{
s->img_file = f;
s->buflen = sizeof(s->buffer_start);
s->img_buffer_end = s->buffer_start + s->buflen;
s->img_buffer = s->img_buffer_end;
s->from_file = 1;
}
#endif
static void start_mem(stbi *s, uint8 const *buffer, int len)
{
#ifndef STBI_NO_STDIO
s->img_file = NULL;
s->from_file = 0;
#endif
s->img_buffer = (uint8 *) buffer;
s->img_buffer_end = (uint8 *) buffer+len;
}
#ifndef STBI_NO_STDIO
static void refill_buffer(stbi *s)
{
int n = fread(s->buffer_start, 1, s->buflen, s->img_file);
if (n == 0) {
s->from_file = 0;
s->img_buffer = s->img_buffer_end-1;
*s->img_buffer = 0;
} else {
s->img_buffer = s->buffer_start;
s->img_buffer_end = s->buffer_start + n;
}
}
#endif
__forceinline static int get8(stbi *s)
{
if (s->img_buffer < s->img_buffer_end)
return *s->img_buffer++;
#ifndef STBI_NO_STDIO
if (s->from_file) {
refill_buffer(s);
return *s->img_buffer++;
}
#endif
return 0;
}
__forceinline static int at_eof(stbi *s)
{
#ifndef STBI_NO_STDIO
if (s->img_file) {
if (!feof(s->img_file)) return 0;
// if feof() is true, check if buffer = end
// special case: we've only got the special 0 character at the end
if (s->from_file == 0) return 1;
}
#endif
return s->img_buffer >= s->img_buffer_end;
}
__forceinline static uint8 get8u(stbi *s)
{
return (uint8) get8(s);
}
static void skip(stbi *s, int n)
{
#ifndef STBI_NO_STDIO
if (s->img_file) {
int blen = s->img_buffer_end - s->img_buffer;
if (blen < n) {
s->img_buffer = s->img_buffer_end;
fseek(s->img_file, n - blen, SEEK_CUR);
return;
}
}
#endif
s->img_buffer += n;
}
static int getn(stbi *s, stbi_uc *buffer, int n)
{
#ifndef STBI_NO_STDIO
if (s->img_file) {
int blen = s->img_buffer_end - s->img_buffer;
if (blen < n) {
int res;
memcpy(buffer, s->img_buffer, blen);
res = ((int) fread(buffer + blen, 1, n - blen, s->img_file) == (n-blen));
s->img_buffer = s->img_buffer_end;
return res;
}
}
#endif
if (s->img_buffer+n <= s->img_buffer_end) {
memcpy(buffer, s->img_buffer, n);
s->img_buffer += n;
return 1;
} else
return 0;
}
static int get16(stbi *s)
{
int z = get8(s);
return (z << 8) + get8(s);
}
static uint32 get32(stbi *s)
{
uint32 z = get16(s);
return (z << 16) + get16(s);
}
static int get16le(stbi *s)
{
int z = get8(s);
return z + (get8(s) << 8);
}
static uint32 get32le(stbi *s)
{
uint32 z = get16le(s);
return z + (get16le(s) << 16);
}
//////////////////////////////////////////////////////////////////////////////
//
// generic converter from built-in img_n to req_comp
// individual types do this automatically as much as possible (e.g. jpeg
// does all cases internally since it needs to colorspace convert anyway,
// and it never has alpha, so very few cases ). png can automatically
// interleave an alpha=255 channel, but falls back to this for other cases
//
// assume data buffer is malloced, so malloc a new one and free that one
// only failure mode is malloc failing
static uint8 compute_y(int r, int g, int b)
{
return (uint8) (((r*77) + (g*150) + (29*b)) >> 8);
}
static unsigned char *convert_format(unsigned char *data, int img_n, int req_comp, uint x, uint y)
{
int i,j;
unsigned char *good;
if (req_comp == img_n) return data;
assert(req_comp >= 1 && req_comp <= 4);
good = (unsigned char *) malloc(req_comp * x * y);
if (good == NULL) {
free(data);
return epuc("outofmem", "Out of memory");
}
for (j=0; j < (int) y; ++j) {
unsigned char *src = data + j * x * img_n ;
unsigned char *dest = good + j * x * req_comp;
#define COMBO(a,b) ((a)*8+(b))
#define CASE(a,b) case COMBO(a,b): for(i=x-1; i >= 0; --i, src += a, dest += b)
// convert source image with img_n components to one with req_comp components;
// avoid switch per pixel, so use switch per scanline and massive macros
switch (COMBO(img_n, req_comp)) {
CASE(1,2) dest[0]=src[0], dest[1]=255; break;
CASE(1,3) dest[0]=dest[1]=dest[2]=src[0]; break;
CASE(1,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=255; break;
CASE(2,1) dest[0]=src[0]; break;
CASE(2,3) dest[0]=dest[1]=dest[2]=src[0]; break;
CASE(2,4) dest[0]=dest[1]=dest[2]=src[0], dest[3]=src[1]; break;
CASE(3,4) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2],dest[3]=255; break;
CASE(3,1) dest[0]=compute_y(src[0],src[1],src[2]); break;
CASE(3,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = 255; break;
CASE(4,1) dest[0]=compute_y(src[0],src[1],src[2]); break;
CASE(4,2) dest[0]=compute_y(src[0],src[1],src[2]), dest[1] = src[3]; break;
CASE(4,3) dest[0]=src[0],dest[1]=src[1],dest[2]=src[2]; break;
default: assert(0);
}
#undef CASE
}
free(data);
return good;
}
#ifndef STBI_NO_HDR
static float *ldr_to_hdr(stbi_uc *data, int x, int y, int comp)
{
int i,k,n;
float *output = (float *) malloc(x * y * comp * sizeof(float));
if (output == NULL) { free(data); return epf("outofmem", "Out of memory"); }
// compute number of non-alpha components
if (comp & 1) n = comp; else n = comp-1;
for (i=0; i < x*y; ++i) {
for (k=0; k < n; ++k) {
output[i*comp + k] = (float) pow(data[i*comp+k]/255.0f, l2h_gamma) * l2h_scale;
}
if (k < comp) output[i*comp + k] = data[i*comp+k]/255.0f;