-
Notifications
You must be signed in to change notification settings - Fork 20
/
jdmarker.c
1360 lines (1138 loc) · 40.2 KB
/
jdmarker.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
/*
* jdmarker.c
*
* Copyright (C) 1991-1998, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains routines to decode JPEG datastream markers.
* Most of the complexity arises from our desire to support input
* suspension: if not all of the data for a marker is available,
* we must exit back to the application. On resumption, we reprocess
* the marker.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
typedef enum { /* JPEG marker codes */
M_SOF0 = 0xc0,
M_SOF1 = 0xc1,
M_SOF2 = 0xc2,
M_SOF3 = 0xc3,
M_SOF5 = 0xc5,
M_SOF6 = 0xc6,
M_SOF7 = 0xc7,
M_JPG = 0xc8,
M_SOF9 = 0xc9,
M_SOF10 = 0xca,
M_SOF11 = 0xcb,
M_SOF13 = 0xcd,
M_SOF14 = 0xce,
M_SOF15 = 0xcf,
M_DHT = 0xc4,
M_DAC = 0xcc,
M_RST0 = 0xd0,
M_RST1 = 0xd1,
M_RST2 = 0xd2,
M_RST3 = 0xd3,
M_RST4 = 0xd4,
M_RST5 = 0xd5,
M_RST6 = 0xd6,
M_RST7 = 0xd7,
M_SOI = 0xd8,
M_EOI = 0xd9,
M_SOS = 0xda,
M_DQT = 0xdb,
M_DNL = 0xdc,
M_DRI = 0xdd,
M_DHP = 0xde,
M_EXP = 0xdf,
M_APP0 = 0xe0,
M_APP1 = 0xe1,
M_APP2 = 0xe2,
M_APP3 = 0xe3,
M_APP4 = 0xe4,
M_APP5 = 0xe5,
M_APP6 = 0xe6,
M_APP7 = 0xe7,
M_APP8 = 0xe8,
M_APP9 = 0xe9,
M_APP10 = 0xea,
M_APP11 = 0xeb,
M_APP12 = 0xec,
M_APP13 = 0xed,
M_APP14 = 0xee,
M_APP15 = 0xef,
M_JPG0 = 0xf0,
M_JPG13 = 0xfd,
M_COM = 0xfe,
M_TEM = 0x01,
M_ERROR = 0x100
} JPEG_MARKER;
/* Private state */
typedef struct {
struct jpeg_marker_reader pub; /* public fields */
/* Application-overridable marker processing methods */
jpeg_marker_parser_method process_COM;
jpeg_marker_parser_method process_APPn[16];
/* Limit on marker data length to save for each marker type */
unsigned int length_limit_COM;
unsigned int length_limit_APPn[16];
/* Status of COM/APPn marker saving */
jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */
unsigned int bytes_read; /* data bytes read so far in marker */
/* Note: cur_marker is not linked into marker_list until it's all read. */
} my_marker_reader;
typedef my_marker_reader * my_marker_ptr;
/*
* Macros for fetching data from the data source module.
*
* At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect
* the current restart point; we update them only when we have reached a
* suitable place to restart if a suspension occurs.
*/
/* Declare and initialize local copies of input pointer/count */
#define INPUT_VARS(cinfo) \
struct jpeg_source_mgr * datasrc = (cinfo)->src; \
const JOCTET * next_input_byte = datasrc->next_input_byte; \
size_t bytes_in_buffer = datasrc->bytes_in_buffer
/* Unload the local copies --- do this only at a restart boundary */
#define INPUT_SYNC(cinfo) \
( datasrc->next_input_byte = next_input_byte, \
datasrc->bytes_in_buffer = bytes_in_buffer )
/* Reload the local copies --- used only in MAKE_BYTE_AVAIL */
#define INPUT_RELOAD(cinfo) \
( next_input_byte = datasrc->next_input_byte, \
bytes_in_buffer = datasrc->bytes_in_buffer )
/* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available.
* Note we do *not* do INPUT_SYNC before calling fill_input_buffer,
* but we must reload the local copies after a successful fill.
*/
#define MAKE_BYTE_AVAIL(cinfo,action) \
if (bytes_in_buffer == 0) { \
if (! (*datasrc->fill_input_buffer) (cinfo)) \
{ action; } \
INPUT_RELOAD(cinfo); \
}
/* Read a byte into variable V.
* If must suspend, take the specified action (typically "return FALSE").
*/
#define INPUT_BYTE(cinfo,V,action) \
MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \
bytes_in_buffer--; \
V = GETJOCTET(*next_input_byte++); )
/* As above, but read two bytes interpreted as an unsigned 16-bit integer.
* V should be declared unsigned int or perhaps INT32.
*/
#define INPUT_2BYTES(cinfo,V,action) \
MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \
bytes_in_buffer--; \
V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \
MAKE_BYTE_AVAIL(cinfo,action); \
bytes_in_buffer--; \
V += GETJOCTET(*next_input_byte++); )
/*
* Routines to process JPEG markers.
*
* Entry condition: JPEG marker itself has been read and its code saved
* in cinfo->unread_marker; input restart point is just after the marker.
*
* Exit: if return TRUE, have read and processed any parameters, and have
* updated the restart point to point after the parameters.
* If return FALSE, was forced to suspend before reaching end of
* marker parameters; restart point has not been moved. Same routine
* will be called again after application supplies more input data.
*
* This approach to suspension assumes that all of a marker's parameters
* can fit into a single input bufferload. This should hold for "normal"
* markers. Some COM/APPn markers might have large parameter segments
* that might not fit. If we are simply dropping such a marker, we use
* skip_input_data to get past it, and thereby put the problem on the
* source manager's shoulders. If we are saving the marker's contents
* into memory, we use a slightly different convention: when forced to
* suspend, the marker processor updates the restart point to the end of
* what it's consumed (ie, the end of the buffer) before returning FALSE.
* On resumption, cinfo->unread_marker still contains the marker code,
* but the data source will point to the next chunk of marker data.
* The marker processor must retain internal state to deal with this.
*
* Note that we don't bother to avoid duplicate trace messages if a
* suspension occurs within marker parameters. Other side effects
* require more care.
*/
LOCAL(boolean)
get_soi (j_decompress_ptr cinfo)
/* Process an SOI marker */
{
int i;
TRACEMS(cinfo, 1, JTRC_SOI);
if (cinfo->marker->saw_SOI)
ERREXIT(cinfo, JERR_SOI_DUPLICATE);
/* Reset all parameters that are defined to be reset by SOI */
for (i = 0; i < NUM_ARITH_TBLS; i++) {
cinfo->arith_dc_L[i] = 0;
cinfo->arith_dc_U[i] = 1;
cinfo->arith_ac_K[i] = 5;
}
cinfo->restart_interval = 0;
/* Set initial assumptions for colorspace etc */
cinfo->jpeg_color_space = JCS_UNKNOWN;
cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */
cinfo->saw_JFIF_marker = FALSE;
cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */
cinfo->JFIF_minor_version = 1;
cinfo->density_unit = 0;
cinfo->X_density = 1;
cinfo->Y_density = 1;
cinfo->saw_Adobe_marker = FALSE;
cinfo->Adobe_transform = 0;
cinfo->marker->saw_SOI = TRUE;
return TRUE;
}
LOCAL(boolean)
get_sof (j_decompress_ptr cinfo, boolean is_prog, boolean is_arith)
/* Process a SOFn marker */
{
INT32 length;
int c, ci;
jpeg_component_info * compptr;
INPUT_VARS(cinfo);
cinfo->progressive_mode = is_prog;
cinfo->arith_code = is_arith;
INPUT_2BYTES(cinfo, length, return FALSE);
INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE);
INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE);
INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE);
INPUT_BYTE(cinfo, cinfo->num_components, return FALSE);
length -= 8;
TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker,
(int) cinfo->image_width, (int) cinfo->image_height,
cinfo->num_components);
if (cinfo->marker->saw_SOF)
ERREXIT(cinfo, JERR_SOF_DUPLICATE);
/* We don't support files in which the image height is initially specified */
/* as 0 and is later redefined by DNL. As long as we have to check that, */
/* might as well have a general sanity check. */
if (cinfo->image_height <= 0 || cinfo->image_width <= 0
|| cinfo->num_components <= 0)
ERREXIT(cinfo, JERR_EMPTY_IMAGE);
if (length != (cinfo->num_components * 3))
ERREXIT(cinfo, JERR_BAD_LENGTH);
if (cinfo->comp_info == NULL) /* do only once, even if suspend */
cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small)
((j_common_ptr) cinfo, JPOOL_IMAGE,
cinfo->num_components * SIZEOF(jpeg_component_info));
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->component_index = ci;
INPUT_BYTE(cinfo, compptr->component_id, return FALSE);
INPUT_BYTE(cinfo, c, return FALSE);
compptr->h_samp_factor = (c >> 4) & 15;
compptr->v_samp_factor = (c ) & 15;
INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE);
TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT,
compptr->component_id, compptr->h_samp_factor,
compptr->v_samp_factor, compptr->quant_tbl_no);
}
cinfo->marker->saw_SOF = TRUE;
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
get_sos (j_decompress_ptr cinfo)
/* Process a SOS marker */
{
INT32 length;
int i, ci, n, c, cc;
jpeg_component_info * compptr;
INPUT_VARS(cinfo);
if (! cinfo->marker->saw_SOF)
ERREXIT(cinfo, JERR_SOS_NO_SOF);
INPUT_2BYTES(cinfo, length, return FALSE);
INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */
TRACEMS1(cinfo, 1, JTRC_SOS, n);
if (length != (n * 2 + 6) || n < 1 || n > MAX_COMPS_IN_SCAN)
ERREXIT(cinfo, JERR_BAD_LENGTH);
cinfo->comps_in_scan = n;
/* Collect the component-spec parameters */
for (i = 0; i < n; i++) {
INPUT_BYTE(cinfo, cc, return FALSE);
INPUT_BYTE(cinfo, c, return FALSE);
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
if (cc == compptr->component_id)
goto id_found;
}
ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc);
id_found:
cinfo->cur_comp_info[i] = compptr;
compptr->dc_tbl_no = (c >> 4) & 15;
compptr->ac_tbl_no = (c ) & 15;
TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc,
compptr->dc_tbl_no, compptr->ac_tbl_no);
}
/* Collect the additional scan parameters Ss, Se, Ah/Al. */
INPUT_BYTE(cinfo, c, return FALSE);
cinfo->Ss = c;
INPUT_BYTE(cinfo, c, return FALSE);
cinfo->Se = c;
INPUT_BYTE(cinfo, c, return FALSE);
cinfo->Ah = (c >> 4) & 15;
cinfo->Al = (c ) & 15;
TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se,
cinfo->Ah, cinfo->Al);
/* Prepare to scan data & restart markers */
cinfo->marker->next_restart_num = 0;
/* Count another SOS marker */
cinfo->input_scan_number++;
INPUT_SYNC(cinfo);
return TRUE;
}
#ifdef D_ARITH_CODING_SUPPORTED
LOCAL(boolean)
get_dac (j_decompress_ptr cinfo)
/* Process a DAC marker */
{
INT32 length;
int index, val;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
while (length > 0) {
INPUT_BYTE(cinfo, index, return FALSE);
INPUT_BYTE(cinfo, val, return FALSE);
length -= 2;
TRACEMS2(cinfo, 1, JTRC_DAC, index, val);
if (index < 0 || index >= (2*NUM_ARITH_TBLS))
ERREXIT1(cinfo, JERR_DAC_INDEX, index);
if (index >= NUM_ARITH_TBLS) { /* define AC table */
cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val;
} else { /* define DC table */
cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F);
cinfo->arith_dc_U[index] = (UINT8) (val >> 4);
if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index])
ERREXIT1(cinfo, JERR_DAC_VALUE, val);
}
}
if (length != 0)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_SYNC(cinfo);
return TRUE;
}
#else /* ! D_ARITH_CODING_SUPPORTED */
#define get_dac(cinfo) skip_variable(cinfo)
#endif /* D_ARITH_CODING_SUPPORTED */
LOCAL(boolean)
get_dht (j_decompress_ptr cinfo)
/* Process a DHT marker */
{
INT32 length;
UINT8 bits[17];
UINT8 huffval[256];
int i, index, count;
JHUFF_TBL **htblptr;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
while (length > 16) {
INPUT_BYTE(cinfo, index, return FALSE);
TRACEMS1(cinfo, 1, JTRC_DHT, index);
bits[0] = 0;
count = 0;
for (i = 1; i <= 16; i++) {
INPUT_BYTE(cinfo, bits[i], return FALSE);
count += bits[i];
}
length -= 1 + 16;
TRACEMS8(cinfo, 2, JTRC_HUFFBITS,
bits[1], bits[2], bits[3], bits[4],
bits[5], bits[6], bits[7], bits[8]);
TRACEMS8(cinfo, 2, JTRC_HUFFBITS,
bits[9], bits[10], bits[11], bits[12],
bits[13], bits[14], bits[15], bits[16]);
/* Here we just do minimal validation of the counts to avoid walking
* off the end of our table space. jdhuff.c will check more carefully.
*/
if (count > 256 || ((INT32) count) > length)
ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
for (i = 0; i < count; i++)
INPUT_BYTE(cinfo, huffval[i], return FALSE);
length -= count;
if (index & 0x10) { /* AC table definition */
index -= 0x10;
htblptr = &cinfo->ac_huff_tbl_ptrs[index];
} else { /* DC table definition */
htblptr = &cinfo->dc_huff_tbl_ptrs[index];
}
if (index < 0 || index >= NUM_HUFF_TBLS)
ERREXIT1(cinfo, JERR_DHT_INDEX, index);
if (*htblptr == NULL)
*htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));
MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval));
}
if (length != 0)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
get_dqt (j_decompress_ptr cinfo)
/* Process a DQT marker */
{
INT32 length;
int n, i, prec;
unsigned int tmp;
JQUANT_TBL *quant_ptr;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
while (length > 0) {
INPUT_BYTE(cinfo, n, return FALSE);
prec = n >> 4;
n &= 0x0F;
TRACEMS2(cinfo, 1, JTRC_DQT, n, prec);
if (n >= NUM_QUANT_TBLS)
ERREXIT1(cinfo, JERR_DQT_INDEX, n);
if (cinfo->quant_tbl_ptrs[n] == NULL)
cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo);
quant_ptr = cinfo->quant_tbl_ptrs[n];
for (i = 0; i < DCTSIZE2; i++) {
if (prec)
INPUT_2BYTES(cinfo, tmp, return FALSE);
else
INPUT_BYTE(cinfo, tmp, return FALSE);
/* We convert the zigzag-order table to natural array order. */
quant_ptr->quantval[jpeg_natural_order[i]] = (UINT16) tmp;
}
if (cinfo->err->trace_level >= 2) {
for (i = 0; i < DCTSIZE2; i += 8) {
TRACEMS8(cinfo, 2, JTRC_QUANTVALS,
quant_ptr->quantval[i], quant_ptr->quantval[i+1],
quant_ptr->quantval[i+2], quant_ptr->quantval[i+3],
quant_ptr->quantval[i+4], quant_ptr->quantval[i+5],
quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]);
}
}
length -= DCTSIZE2+1;
if (prec) length -= DCTSIZE2;
}
if (length != 0)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
get_dri (j_decompress_ptr cinfo)
/* Process a DRI marker */
{
INT32 length;
unsigned int tmp;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
if (length != 4)
ERREXIT(cinfo, JERR_BAD_LENGTH);
INPUT_2BYTES(cinfo, tmp, return FALSE);
TRACEMS1(cinfo, 1, JTRC_DRI, tmp);
cinfo->restart_interval = tmp;
INPUT_SYNC(cinfo);
return TRUE;
}
/*
* Routines for processing APPn and COM markers.
* These are either saved in memory or discarded, per application request.
* APP0 and APP14 are specially checked to see if they are
* JFIF and Adobe markers, respectively.
*/
#define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */
#define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */
#define APPN_DATA_LEN 14 /* Must be the largest of the above!! */
LOCAL(void)
examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data,
unsigned int datalen, INT32 remaining)
/* Examine first few bytes from an APP0.
* Take appropriate action if it is a JFIF marker.
* datalen is # of bytes at data[], remaining is length of rest of marker data.
*/
{
INT32 totallen = (INT32) datalen + remaining;
if (datalen >= APP0_DATA_LEN &&
GETJOCTET(data[0]) == 0x4A &&
GETJOCTET(data[1]) == 0x46 &&
GETJOCTET(data[2]) == 0x49 &&
GETJOCTET(data[3]) == 0x46 &&
GETJOCTET(data[4]) == 0) {
/* Found JFIF APP0 marker: save info */
cinfo->saw_JFIF_marker = TRUE;
cinfo->JFIF_major_version = GETJOCTET(data[5]);
cinfo->JFIF_minor_version = GETJOCTET(data[6]);
cinfo->density_unit = GETJOCTET(data[7]);
cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]);
cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]);
/* Check version.
* Major version must be 1, anything else signals an incompatible change.
* (We used to treat this as an error, but now it's a nonfatal warning,
* because some bozo at Hijaak couldn't read the spec.)
* Minor version should be 0..2, but process anyway if newer.
*/
if (cinfo->JFIF_major_version != 1)
WARNMS2(cinfo, JWRN_JFIF_MAJOR,
cinfo->JFIF_major_version, cinfo->JFIF_minor_version);
/* Generate trace messages */
TRACEMS5(cinfo, 1, JTRC_JFIF,
cinfo->JFIF_major_version, cinfo->JFIF_minor_version,
cinfo->X_density, cinfo->Y_density, cinfo->density_unit);
/* Validate thumbnail dimensions and issue appropriate messages */
if (GETJOCTET(data[12]) | GETJOCTET(data[13]))
TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL,
GETJOCTET(data[12]), GETJOCTET(data[13]));
totallen -= APP0_DATA_LEN;
if (totallen !=
((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3))
TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen);
} else if (datalen >= 6 &&
GETJOCTET(data[0]) == 0x4A &&
GETJOCTET(data[1]) == 0x46 &&
GETJOCTET(data[2]) == 0x58 &&
GETJOCTET(data[3]) == 0x58 &&
GETJOCTET(data[4]) == 0) {
/* Found JFIF "JFXX" extension APP0 marker */
/* The library doesn't actually do anything with these,
* but we try to produce a helpful trace message.
*/
switch (GETJOCTET(data[5])) {
case 0x10:
TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen);
break;
case 0x11:
TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen);
break;
case 0x13:
TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen);
break;
default:
TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION,
GETJOCTET(data[5]), (int) totallen);
break;
}
} else {
/* Start of APP0 does not match "JFIF" or "JFXX", or too short */
TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen);
}
}
LOCAL(void)
examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data,
unsigned int datalen, INT32 remaining)
/* Examine first few bytes from an APP14.
* Take appropriate action if it is an Adobe marker.
* datalen is # of bytes at data[], remaining is length of rest of marker data.
*/
{
unsigned int version, flags0, flags1, transform;
if (datalen >= APP14_DATA_LEN &&
GETJOCTET(data[0]) == 0x41 &&
GETJOCTET(data[1]) == 0x64 &&
GETJOCTET(data[2]) == 0x6F &&
GETJOCTET(data[3]) == 0x62 &&
GETJOCTET(data[4]) == 0x65) {
/* Found Adobe APP14 marker */
version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]);
flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]);
flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]);
transform = GETJOCTET(data[11]);
TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform);
cinfo->saw_Adobe_marker = TRUE;
cinfo->Adobe_transform = (UINT8) transform;
} else {
/* Start of APP14 does not match "Adobe", or too short */
TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining));
}
}
METHODDEF(boolean)
get_interesting_appn (j_decompress_ptr cinfo)
/* Process an APP0 or APP14 marker without saving it */
{
INT32 length;
JOCTET b[APPN_DATA_LEN];
unsigned int i, numtoread;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
/* get the interesting part of the marker data */
if (length >= APPN_DATA_LEN)
numtoread = APPN_DATA_LEN;
else if (length > 0)
numtoread = (unsigned int) length;
else
numtoread = 0;
for (i = 0; i < numtoread; i++)
INPUT_BYTE(cinfo, b[i], return FALSE);
length -= numtoread;
/* process it */
switch (cinfo->unread_marker) {
case M_APP0:
examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length);
break;
case M_APP14:
examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length);
break;
default:
/* can't get here unless jpeg_save_markers chooses wrong processor */
ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);
break;
}
/* skip any remaining data -- could be lots */
INPUT_SYNC(cinfo);
if (length > 0)
(*cinfo->src->skip_input_data) (cinfo, (long) length);
return TRUE;
}
#ifdef SAVE_MARKERS_SUPPORTED
METHODDEF(boolean)
save_marker (j_decompress_ptr cinfo)
/* Save an APPn or COM marker into the marker list */
{
my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
jpeg_saved_marker_ptr cur_marker = marker->cur_marker;
unsigned int bytes_read, data_length;
JOCTET FAR * data;
INT32 length = 0;
INPUT_VARS(cinfo);
if (cur_marker == NULL) {
/* begin reading a marker */
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
if (length >= 0) { /* watch out for bogus length word */
/* figure out how much we want to save */
unsigned int limit;
if (cinfo->unread_marker == (int) M_COM)
limit = marker->length_limit_COM;
else
limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0];
if ((unsigned int) length < limit)
limit = (unsigned int) length;
/* allocate and initialize the marker item */
cur_marker = (jpeg_saved_marker_ptr)
(*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
SIZEOF(struct jpeg_marker_struct) + limit);
cur_marker->next = NULL;
cur_marker->marker = (UINT8) cinfo->unread_marker;
cur_marker->original_length = (unsigned int) length;
cur_marker->data_length = limit;
/* data area is just beyond the jpeg_marker_struct */
data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1);
marker->cur_marker = cur_marker;
marker->bytes_read = 0;
bytes_read = 0;
data_length = limit;
} else {
/* deal with bogus length word */
bytes_read = data_length = 0;
data = NULL;
}
} else {
/* resume reading a marker */
bytes_read = marker->bytes_read;
data_length = cur_marker->data_length;
data = cur_marker->data + bytes_read;
}
while (bytes_read < data_length) {
INPUT_SYNC(cinfo); /* move the restart point to here */
marker->bytes_read = bytes_read;
/* If there's not at least one byte in buffer, suspend */
MAKE_BYTE_AVAIL(cinfo, return FALSE);
/* Copy bytes with reasonable rapidity */
while (bytes_read < data_length && bytes_in_buffer > 0) {
*data++ = *next_input_byte++;
bytes_in_buffer--;
bytes_read++;
}
}
/* Done reading what we want to read */
if (cur_marker != NULL) { /* will be NULL if bogus length word */
/* Add new marker to end of list */
if (cinfo->marker_list == NULL) {
cinfo->marker_list = cur_marker;
} else {
jpeg_saved_marker_ptr prev = cinfo->marker_list;
while (prev->next != NULL)
prev = prev->next;
prev->next = cur_marker;
}
/* Reset pointer & calc remaining data length */
data = cur_marker->data;
length = cur_marker->original_length - data_length;
}
/* Reset to initial state for next marker */
marker->cur_marker = NULL;
/* Process the marker if interesting; else just make a generic trace msg */
switch (cinfo->unread_marker) {
case M_APP0:
examine_app0(cinfo, data, data_length, length);
break;
case M_APP14:
examine_app14(cinfo, data, data_length, length);
break;
default:
TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker,
(int) (data_length + length));
break;
}
/* skip any remaining data -- could be lots */
INPUT_SYNC(cinfo); /* do before skip_input_data */
if (length > 0)
(*cinfo->src->skip_input_data) (cinfo, (long) length);
return TRUE;
}
#endif /* SAVE_MARKERS_SUPPORTED */
METHODDEF(boolean)
skip_variable (j_decompress_ptr cinfo)
/* Skip over an unknown or uninteresting variable-length marker */
{
INT32 length;
INPUT_VARS(cinfo);
INPUT_2BYTES(cinfo, length, return FALSE);
length -= 2;
TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length);
INPUT_SYNC(cinfo); /* do before skip_input_data */
if (length > 0)
(*cinfo->src->skip_input_data) (cinfo, (long) length);
return TRUE;
}
/*
* Find the next JPEG marker, save it in cinfo->unread_marker.
* Returns FALSE if had to suspend before reaching a marker;
* in that case cinfo->unread_marker is unchanged.
*
* Note that the result might not be a valid marker code,
* but it will never be 0 or FF.
*/
LOCAL(boolean)
next_marker (j_decompress_ptr cinfo)
{
int c;
INPUT_VARS(cinfo);
for (;;) {
INPUT_BYTE(cinfo, c, return FALSE);
/* Skip any non-FF bytes.
* This may look a bit inefficient, but it will not occur in a valid file.
* We sync after each discarded byte so that a suspending data source
* can discard the byte from its buffer.
*/
while (c != 0xFF) {
cinfo->marker->discarded_bytes++;
INPUT_SYNC(cinfo);
INPUT_BYTE(cinfo, c, return FALSE);
}
/* This loop swallows any duplicate FF bytes. Extra FFs are legal as
* pad bytes, so don't count them in discarded_bytes. We assume there
* will not be so many consecutive FF bytes as to overflow a suspending
* data source's input buffer.
*/
do {
INPUT_BYTE(cinfo, c, return FALSE);
} while (c == 0xFF);
if (c != 0)
break; /* found a valid marker, exit loop */
/* Reach here if we found a stuffed-zero data sequence (FF/00).
* Discard it and loop back to try again.
*/
cinfo->marker->discarded_bytes += 2;
INPUT_SYNC(cinfo);
}
if (cinfo->marker->discarded_bytes != 0) {
WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c);
cinfo->marker->discarded_bytes = 0;
}
cinfo->unread_marker = c;
INPUT_SYNC(cinfo);
return TRUE;
}
LOCAL(boolean)
first_marker (j_decompress_ptr cinfo)
/* Like next_marker, but used to obtain the initial SOI marker. */
/* For this marker, we do not allow preceding garbage or fill; otherwise,
* we might well scan an entire input file before realizing it ain't JPEG.
* If an application wants to process non-JFIF files, it must seek to the
* SOI before calling the JPEG library.
*/
{
int c, c2;
INPUT_VARS(cinfo);
INPUT_BYTE(cinfo, c, return FALSE);
INPUT_BYTE(cinfo, c2, return FALSE);
if (c != 0xFF || c2 != (int) M_SOI)
ERREXIT2(cinfo, JERR_NO_SOI, c, c2);
cinfo->unread_marker = c2;
INPUT_SYNC(cinfo);
return TRUE;
}
/*
* Read markers until SOS or EOI.
*
* Returns same codes as are defined for jpeg_consume_input:
* JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
*/
METHODDEF(int)
read_markers (j_decompress_ptr cinfo)
{
/* Outer loop repeats once for each marker. */
for (;;) {
/* Collect the marker proper, unless we already did. */
/* NB: first_marker() enforces the requirement that SOI appear first. */
if (cinfo->unread_marker == 0) {
if (! cinfo->marker->saw_SOI) {
if (! first_marker(cinfo))
return JPEG_SUSPENDED;
} else {
if (! next_marker(cinfo))
return JPEG_SUSPENDED;
}
}
/* At this point cinfo->unread_marker contains the marker code and the
* input point is just past the marker proper, but before any parameters.
* A suspension will cause us to return with this state still true.
*/
switch (cinfo->unread_marker) {
case M_SOI:
if (! get_soi(cinfo))
return JPEG_SUSPENDED;
break;
case M_SOF0: /* Baseline */
case M_SOF1: /* Extended sequential, Huffman */
if (! get_sof(cinfo, FALSE, FALSE))
return JPEG_SUSPENDED;
break;
case M_SOF2: /* Progressive, Huffman */
if (! get_sof(cinfo, TRUE, FALSE))
return JPEG_SUSPENDED;
break;
case M_SOF9: /* Extended sequential, arithmetic */
if (! get_sof(cinfo, FALSE, TRUE))
return JPEG_SUSPENDED;
break;
case M_SOF10: /* Progressive, arithmetic */
if (! get_sof(cinfo, TRUE, TRUE))
return JPEG_SUSPENDED;
break;
/* Currently unsupported SOFn types */
case M_SOF3: /* Lossless, Huffman */
case M_SOF5: /* Differential sequential, Huffman */