summaryrefslogtreecommitdiff
path: root/libavformat/asfdec_o.c
blob: 5122e33c7870653e3f8c946d02f547c4973b6305 (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
/*
 * Microsoft Advanced Streaming Format demuxer
 * Copyright (c) 2014 Alexandra Hájková
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/attributes.h"
#include "libavutil/avstring.h"
#include "libavutil/bswap.h"
#include "libavutil/common.h"
#include "libavutil/dict.h"
#include "libavutil/internal.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/time_internal.h"

#include "avformat.h"
#include "avio_internal.h"
#include "avlanguage.h"
#include "id3v2.h"
#include "internal.h"
#include "riff.h"
#include "asf.h"
#include "asfcrypt.h"

#define ASF_BOOL                              0x2
#define ASF_WORD                              0x5
#define ASF_GUID                              0x6
#define ASF_DWORD                             0x3
#define ASF_QWORD                             0x4
#define ASF_UNICODE                           0x0
#define ASF_FLAG_BROADCAST                    0x1
#define ASF_BYTE_ARRAY                        0x1
#define ASF_TYPE_AUDIO                        0x2
#define ASF_TYPE_VIDEO                        0x1
#define ASF_STREAM_NUM                        0x7F
#define ASF_MAX_STREAMS                       128
#define BMP_HEADER_SIZE                       40
#define ASF_NUM_OF_PAYLOADS                   0x3F
#define ASF_ERROR_CORRECTION_LENGTH_TYPE      0x60
#define ASF_PACKET_ERROR_CORRECTION_DATA_SIZE 0x2

typedef struct GUIDParseTable {
    const char *name;
    ff_asf_guid guid;
    int (*read_object)(AVFormatContext *, const struct GUIDParseTable *);
    int is_subobject;
} GUIDParseTable;

typedef struct ASFPacket {
    AVPacket avpkt;
    int64_t dts;
    uint32_t frame_num; // ASF payloads with the same number are parts of the same frame
    int flags;
    int data_size;
    int duration;
    int size_left;
    uint8_t stream_index;
} ASFPacket;

typedef struct ASFStream {
    uint8_t stream_index; // from packet header
    int index;  // stream index in AVFormatContext, set in asf_read_stream_properties
    int type;
    int indexed; // added index entries from the Simple Index Object or not
    int8_t span;   // for deinterleaving
    uint16_t virtual_pkt_len;
    uint16_t virtual_chunk_len;
    int16_t lang_idx;
    ASFPacket pkt;
} ASFStream;

typedef struct ASFStreamData{
    char langs[32];
    AVDictionary *asf_met; // for storing per-stream metadata
    AVRational aspect_ratio;
} ASFStreamData;

typedef struct ASFContext {
    int data_reached;
    int is_simple_index; // is simple index present or not 1/0
    int is_header;

    uint64_t preroll;
    uint64_t nb_packets; // ASF packets
    uint32_t packet_size;
    int64_t send_time;
    int duration;

    uint32_t b_flags;    // flags with broadcast flag
    uint32_t prop_flags; // file properties object flags

    uint64_t data_size; // data object size
    uint64_t unknown_size; // size of the unknown object

    int64_t offset; // offset of the current object

    int64_t data_offset;
    int64_t first_packet_offset; // packet offset
    int64_t unknown_offset;   // for top level header objects or subobjects without specified behavior

    // ASF file must not contain more than 128 streams according to the specification
    ASFStream *asf_st[ASF_MAX_STREAMS];
    ASFStreamData asf_sd[ASF_MAX_STREAMS];
    int nb_streams;

    int stream_index; // from packet header, for the subpayload case

    // packet parameters
    uint64_t sub_header_offset; // offset of subpayload header
    int64_t sub_dts;
    uint8_t dts_delta; // for subpayloads
    uint32_t packet_size_internal; // packet size stored inside ASFPacket, can be 0
    int64_t packet_offset; // offset of the current packet inside Data Object
    uint32_t pad_len; // padding after payload
    uint32_t rep_data_len;

    // packet state
    uint64_t sub_left;  // subpayloads left or not
    unsigned int nb_sub; // number of subpayloads read so far from the current ASF packet
    uint16_t mult_sub_len; // total length of subpayloads array inside multiple payload
    uint64_t nb_mult_left; // multiple payloads left
    int return_subpayload;
    enum {
        PARSE_PACKET_HEADER,
        READ_SINGLE,
        READ_MULTI,
        READ_MULTI_SUB
    } state;
} ASFContext;

static int detect_unknown_subobject(AVFormatContext *s, int64_t offset, int64_t size);
static const GUIDParseTable *find_guid(ff_asf_guid guid);

static int asf_probe(AVProbeData *pd)
{
    /* check file header */
    if (!ff_guidcmp(pd->buf, &ff_asf_header))
        return AVPROBE_SCORE_MAX/2;
    else
        return 0;
}

static void swap_guid(ff_asf_guid guid)
{
    FFSWAP(unsigned char, guid[0], guid[3]);
    FFSWAP(unsigned char, guid[1], guid[2]);
    FFSWAP(unsigned char, guid[4], guid[5]);
    FFSWAP(unsigned char, guid[6], guid[7]);
}

static void align_position(AVIOContext *pb,  int64_t offset, uint64_t size)
{
    if (size < INT64_MAX - offset && avio_tell(pb) != offset + size)
        avio_seek(pb, offset + size, SEEK_SET);
}

static int asf_read_unknown(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint64_t size   = avio_rl64(pb);
    int ret;

    if (size > INT64_MAX)
        return AVERROR_INVALIDDATA;

    if (asf->is_header)
        asf->unknown_size = size;
    asf->is_header = 0;
    if (!g->is_subobject) {
        if (!(ret = strcmp(g->name, "Header Extension")))
            avio_skip(pb, 22); // skip reserved fields and Data Size
        if ((ret = detect_unknown_subobject(s, asf->unknown_offset,
                                            asf->unknown_size)) < 0)
            return ret;
    } else {
        if (size < 24) {
            av_log(s, AV_LOG_ERROR, "Too small size %"PRIu64" (< 24).\n", size);
            return AVERROR_INVALIDDATA;
        }
        avio_skip(pb, size - 24);
    }

    return 0;
}

static int get_asf_string(AVIOContext *pb, int maxlen, char *buf, int buflen)
{
    char *q = buf;
    int ret = 0;
    if (buflen <= 0)
        return AVERROR(EINVAL);
    while (ret + 1 < maxlen) {
        uint8_t tmp;
        uint32_t ch;
        GET_UTF16(ch, (ret += 2) <= maxlen ? avio_rl16(pb) : 0, break;);
        PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)
    }
    *q = 0;

    return ret;
}

static int asf_read_marker(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint64_t size   = avio_rl64(pb);
    int i, nb_markers, ret;
    size_t len;
    char name[1024];

    avio_skip(pb, 8);
    avio_skip(pb, 8); // skip reserved GUID
    nb_markers = avio_rl32(pb);
    avio_skip(pb, 2); // skip reserved field
    len = avio_rl16(pb);
    for (i = 0; i < len; i++)
        avio_skip(pb, 1);

    for (i = 0; i < nb_markers; i++) {
        int64_t pts;

        avio_skip(pb, 8);
        pts = avio_rl64(pb);
        pts -= asf->preroll * 10000;
        avio_skip(pb, 2); // entry length
        avio_skip(pb, 4); // send time
        avio_skip(pb, 4); // flags
        len = avio_rl32(pb);

        if ((ret = avio_get_str16le(pb, len, name,
                                    sizeof(name))) < len)
            avio_skip(pb, len - ret);
        avpriv_new_chapter(s, i, (AVRational) { 1, 10000000 }, pts,
                           AV_NOPTS_VALUE, name);
    }
    align_position(pb, asf->offset, size);

    return 0;
}

static int asf_read_metadata(AVFormatContext *s, const char *title, uint16_t len,
                             unsigned char *ch, uint16_t buflen)
{
    AVIOContext *pb = s->pb;

    avio_get_str16le(pb, len, ch, buflen);
    if (ch[0]) {
        if (av_dict_set(&s->metadata, title, ch, 0) < 0)
            av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");
    }

    return 0;
}

static int asf_read_value(AVFormatContext *s, const uint8_t *name,
                          uint16_t val_len, int type, AVDictionary **met)
{
    int ret;
    uint8_t *value;
    uint16_t buflen = 2 * val_len + 1;
    AVIOContext *pb = s->pb;

    value = av_malloc(buflen);
    if (!value)
        return AVERROR(ENOMEM);
    if (type == ASF_UNICODE) {
        // get_asf_string reads UTF-16 and converts it to UTF-8 which needs longer buffer
        if ((ret = get_asf_string(pb, val_len, value, buflen)) < 0)
            goto failed;
        if (av_dict_set(met, name, value, 0) < 0)
            av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");
    } else {
        char buf[256];
        if (val_len > sizeof(buf)) {
            ret = AVERROR_INVALIDDATA;
            goto failed;
        }
        if ((ret = avio_read(pb, value, val_len)) < 0)
            goto failed;
        if (ret < 2 * val_len)
            value[ret] = '\0';
        else
            value[2 * val_len - 1] = '\0';
        snprintf(buf, sizeof(buf), "%s", value);
        if (av_dict_set(met, name, buf, 0) < 0)
            av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");
    }
    av_freep(&value);

    return 0;

failed:
    av_freep(&value);
    return ret;
}
static int asf_read_generic_value(AVIOContext *pb, int type, uint64_t *value)
{

    switch (type) {
    case ASF_BOOL:
        *value = avio_rl16(pb);
        break;
    case ASF_DWORD:
        *value = avio_rl32(pb);
        break;
    case ASF_QWORD:
        *value = avio_rl64(pb);
        break;
    case ASF_WORD:
        *value = avio_rl16(pb);
        break;
    default:
        return AVERROR_INVALIDDATA;
    }

    return 0;
}

static int asf_set_metadata(AVFormatContext *s, const uint8_t *name,
                            int type, AVDictionary **met)
{
    AVIOContext *pb = s->pb;
    uint64_t value;
    char buf[32];
    int ret;

    ret = asf_read_generic_value(pb, type, &value);
    if (ret < 0)
        return ret;

    snprintf(buf, sizeof(buf), "%"PRIu64, value);
    if (av_dict_set(met, name, buf, 0) < 0)
        av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");

    return 0;
}

/* MSDN claims that this should be "compatible with the ID3 frame, APIC",
 * but in reality this is only loosely similar */
static int asf_read_picture(AVFormatContext *s, int len)
{
    ASFContext *asf       = s->priv_data;
    AVPacket pkt          = { 0 };
    const CodecMime *mime = ff_id3v2_mime_tags;
    enum  AVCodecID id    = AV_CODEC_ID_NONE;
    char mimetype[64];
    uint8_t  *desc = NULL;
    AVStream   *st = NULL;
    int ret, type, picsize, desc_len;
    ASFStream *asf_st;

    /* type + picsize + mime + desc */
    if (len < 1 + 4 + 2 + 2) {
        av_log(s, AV_LOG_ERROR, "Invalid attached picture size: %d.\n", len);
        return AVERROR_INVALIDDATA;
    }

    /* picture type */
    type = avio_r8(s->pb);
    len--;
    if (type >= FF_ARRAY_ELEMS(ff_id3v2_picture_types) || type < 0) {
        av_log(s, AV_LOG_WARNING, "Unknown attached picture type: %d.\n", type);
        type = 0;
    }

    /* picture data size */
    picsize = avio_rl32(s->pb);
    len    -= 4;

    /* picture MIME type */
    len -= avio_get_str16le(s->pb, len, mimetype, sizeof(mimetype));
    while (mime->id != AV_CODEC_ID_NONE) {
        if (!strncmp(mime->str, mimetype, sizeof(mimetype))) {
            id = mime->id;
            break;
        }
        mime++;
    }
    if (id == AV_CODEC_ID_NONE) {
        av_log(s, AV_LOG_ERROR, "Unknown attached picture mimetype: %s.\n",
               mimetype);
        return 0;
    }

    if (picsize >= len) {
        av_log(s, AV_LOG_ERROR, "Invalid attached picture data size: %d >= %d.\n",
               picsize, len);
        return AVERROR_INVALIDDATA;
    }

    /* picture description */
    desc_len = (len - picsize) * 2 + 1;
    desc     = av_malloc(desc_len);
    if (!desc)
        return AVERROR(ENOMEM);
    len -= avio_get_str16le(s->pb, len - picsize, desc, desc_len);

    ret = av_get_packet(s->pb, &pkt, picsize);
    if (ret < 0)
        goto fail;

    st  = avformat_new_stream(s, NULL);
    if (!st) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }
    asf->asf_st[asf->nb_streams] = av_mallocz(sizeof(*asf_st));
    asf_st = asf->asf_st[asf->nb_streams];
    if (!asf_st) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }

    st->disposition              |= AV_DISPOSITION_ATTACHED_PIC;
    st->codecpar->codec_type      = asf_st->type = AVMEDIA_TYPE_VIDEO;
    st->codecpar->codec_id        = id;
    st->attached_pic              = pkt;
    st->attached_pic.stream_index = asf_st->index = st->index;
    st->attached_pic.flags       |= AV_PKT_FLAG_KEY;

    asf->nb_streams++;

    if (*desc) {
        if (av_dict_set(&st->metadata, "title", desc, AV_DICT_DONT_STRDUP_VAL) < 0)
            av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");
    } else
        av_freep(&desc);

    if (av_dict_set(&st->metadata, "comment", ff_id3v2_picture_types[type], 0) < 0)
        av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");

    return 0;

fail:
    av_freep(&desc);
    av_packet_unref(&pkt);
    return ret;
}

static void get_id3_tag(AVFormatContext *s, int len)
{
    ID3v2ExtraMeta *id3v2_extra_meta = NULL;

    ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta, len);
    if (id3v2_extra_meta) {
        ff_id3v2_parse_apic(s, &id3v2_extra_meta);
        ff_id3v2_parse_chapters(s, &id3v2_extra_meta);
    }
    ff_id3v2_free_extra_meta(&id3v2_extra_meta);
}

static int process_metadata(AVFormatContext *s, const uint8_t *name, uint16_t name_len,
                            uint16_t val_len, uint16_t type, AVDictionary **met)
{
    int ret;
    ff_asf_guid guid;

    if (val_len) {
        switch (type) {
        case ASF_UNICODE:
            asf_read_value(s, name, val_len, type, met);
            break;
        case ASF_BYTE_ARRAY:
            if (!strcmp(name, "WM/Picture")) // handle cover art
                asf_read_picture(s, val_len);
            else if (!strcmp(name, "ID3")) // handle ID3 tag
                get_id3_tag(s, val_len);
            else
                asf_read_value(s, name, val_len, type, met);
            break;
        case ASF_GUID:
            ff_get_guid(s->pb, &guid);
            break;
        default:
            if ((ret = asf_set_metadata(s, name, type, met)) < 0)
                return ret;
            break;
        }
    }

    return 0;
}

static int asf_read_ext_content(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf  = s->priv_data;
    AVIOContext *pb  = s->pb;
    uint64_t size    = avio_rl64(pb);
    uint16_t nb_desc = avio_rl16(pb);
    int i, ret;

    for (i = 0; i < nb_desc; i++) {
        uint16_t name_len, type, val_len;
        uint8_t *name = NULL;

        name_len = avio_rl16(pb);
        if (!name_len)
            return AVERROR_INVALIDDATA;
        name = av_malloc(name_len);
        if (!name)
            return AVERROR(ENOMEM);
        avio_get_str16le(pb, name_len, name,
                         name_len);
        type    = avio_rl16(pb);
        // BOOL values are 16 bits long in the Metadata Object
        // but 32 bits long in the Extended Content Description Object
        if (type == ASF_BOOL)
            type = ASF_DWORD;
        val_len = avio_rl16(pb);

        ret = process_metadata(s, name, name_len, val_len, type, &s->metadata);
        av_freep(&name);
        if (ret < 0)
            return ret;
    }

    align_position(pb, asf->offset, size);
    return 0;
}

static AVStream *find_stream(AVFormatContext *s, uint16_t st_num)
{
    AVStream *st = NULL;
    ASFContext *asf = s->priv_data;
    int i;

    for (i = 0; i < asf->nb_streams; i++) {
        if (asf->asf_st[i]->stream_index == st_num) {
            st = s->streams[asf->asf_st[i]->index];
            break;
        }
    }

    return st;
}

static int asf_store_aspect_ratio(AVFormatContext *s, uint8_t st_num, uint8_t *name, int type)
{
    ASFContext *asf   = s->priv_data;
    AVIOContext *pb   = s->pb;
    uint64_t value = 0;
    int ret;

    ret = asf_read_generic_value(pb, type, &value);
    if (ret < 0)
        return ret;

    if (st_num < ASF_MAX_STREAMS) {
        if (!strcmp(name, "AspectRatioX"))
            asf->asf_sd[st_num].aspect_ratio.num = value;
        else
            asf->asf_sd[st_num].aspect_ratio.den = value;
    }
    return 0;
}

static int asf_read_metadata_obj(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf   = s->priv_data;
    AVIOContext *pb   = s->pb;
    uint64_t size     = avio_rl64(pb);
    uint16_t nb_recs  = avio_rl16(pb); // number of records in the Description Records list
    int i, ret;

    for (i = 0; i < nb_recs; i++) {
        uint16_t name_len, buflen, type, val_len, st_num;
        uint8_t *name = NULL;

        avio_skip(pb, 2); // skip reserved field
        st_num   = avio_rl16(pb);
        name_len = avio_rl16(pb);
        buflen   = 2 * name_len + 1;
        if (!name_len)
            break;
        type     = avio_rl16(pb);
        val_len  = avio_rl32(pb);
        name     = av_malloc(buflen);
        if (!name)
            return AVERROR(ENOMEM);
        avio_get_str16le(pb, name_len, name,
                         buflen);
        if (!strcmp(name, "AspectRatioX") || !strcmp(name, "AspectRatioY")) {
            ret = asf_store_aspect_ratio(s, st_num, name, type);
            if (ret < 0) {
                av_freep(&name);
                break;
            }
        } else {
            if (st_num < ASF_MAX_STREAMS) {
                if ((ret = process_metadata(s, name, name_len, val_len, type,
                                            &asf->asf_sd[st_num].asf_met)) < 0) {
                    av_freep(&name);
                    break;
                }
            }
        }
        av_freep(&name);
    }

    align_position(pb, asf->offset, size);
    return 0;
}

static int asf_read_content_desc(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    int i;
    static const char *const titles[] =
    { "Title", "Author", "Copyright", "Description", "Rate" };
    uint16_t len[5], buflen[5] = { 0 };
    uint8_t *ch;
    uint64_t size = avio_rl64(pb);

    for (i = 0; i < 5; i++) {
        len[i]  = avio_rl16(pb);
        // utf8 string should be <= 2 * utf16 string, extra byte for the terminator
        buflen[i]  = 2 * len[i] + 1;
    }

    for (i = 0; i < 5; i++) {
        ch = av_malloc(buflen[i]);
        if (!ch)
            return(AVERROR(ENOMEM));
        asf_read_metadata(s, titles[i], len[i], ch, buflen[i]);
        av_freep(&ch);
    }
    align_position(pb, asf->offset, size);

    return 0;
}

static int asf_read_properties(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    time_t creation_time;

    avio_rl64(pb); // read object size
    avio_skip(pb, 16); // skip File ID
    avio_skip(pb, 8);  // skip File size
    creation_time = avio_rl64(pb);
    if (!(asf->b_flags & ASF_FLAG_BROADCAST)) {
        struct tm tmbuf;
        struct tm *tm;
        char buf[64];

        // creation date is in 100 ns units from 1 Jan 1601, conversion to s
        creation_time /= 10000000;
        // there are 11644473600 seconds between 1 Jan 1601 and 1 Jan 1970
        creation_time -= 11644473600;
        tm = gmtime_r(&creation_time, &tmbuf);
        if (tm) {
            if (!strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", tm))
                buf[0] = '\0';
        } else
            buf[0] = '\0';
        if (buf[0]) {
            if (av_dict_set(&s->metadata, "creation_time", buf, 0) < 0)
                av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");
        }
    }
    asf->nb_packets  = avio_rl64(pb);
    asf->duration    = avio_rl64(pb) / 10000; // stream duration
    avio_skip(pb, 8); // skip send duration
    asf->preroll     = avio_rl64(pb);
    asf->duration   -= asf->preroll;
    asf->b_flags     = avio_rl32(pb);
    avio_skip(pb, 4); // skip minimal packet size
    asf->packet_size  = avio_rl32(pb);
    avio_skip(pb, 4); // skip max_bitrate

    return 0;
}

static int parse_video_info(AVIOContext *pb, AVStream *st)
{
    uint16_t size_asf; // ASF-specific Format Data size
    uint32_t size_bmp; // BMP_HEADER-specific Format Data size
    unsigned int tag;

    st->codecpar->width  = avio_rl32(pb);
    st->codecpar->height = avio_rl32(pb);
    avio_skip(pb, 1); // skip reserved flags
    size_asf = avio_rl16(pb);
    tag = ff_get_bmp_header(pb, st, &size_bmp);
    st->codecpar->codec_tag = tag;
    st->codecpar->codec_id  = ff_codec_get_id(ff_codec_bmp_tags, tag);
    size_bmp = FFMAX(size_asf, size_bmp);

    if (size_bmp > BMP_HEADER_SIZE) {
        int ret;
        st->codecpar->extradata_size  = size_bmp - BMP_HEADER_SIZE;
        if (!(st->codecpar->extradata = av_malloc(st->codecpar->extradata_size +
                                               AV_INPUT_BUFFER_PADDING_SIZE))) {
            st->codecpar->extradata_size = 0;
            return AVERROR(ENOMEM);
        }
        memset(st->codecpar->extradata + st->codecpar->extradata_size , 0,
               AV_INPUT_BUFFER_PADDING_SIZE);
        if ((ret = avio_read(pb, st->codecpar->extradata,
                             st->codecpar->extradata_size)) < 0)
            return ret;
    }
    return 0;
}

static int asf_read_stream_properties(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint64_t size;
    uint32_t err_data_len, ts_data_len; // type specific data length
    uint16_t flags;
    ff_asf_guid stream_type;
    enum AVMediaType type;
    int i, ret;
    uint8_t stream_index;
    AVStream *st;
    ASFStream *asf_st;

    // ASF file must not contain more than 128 streams according to the specification
    if (asf->nb_streams >= ASF_MAX_STREAMS)
        return AVERROR_INVALIDDATA;

    size = avio_rl64(pb);
    ff_get_guid(pb, &stream_type);
    if (!ff_guidcmp(&stream_type, &ff_asf_audio_stream))
        type = AVMEDIA_TYPE_AUDIO;
    else if (!ff_guidcmp(&stream_type, &ff_asf_video_stream))
        type = AVMEDIA_TYPE_VIDEO;
    else if (!ff_guidcmp(&stream_type, &ff_asf_jfif_media))
        type = AVMEDIA_TYPE_VIDEO;
    else if (!ff_guidcmp(&stream_type, &ff_asf_command_stream))
        type = AVMEDIA_TYPE_DATA;
    else if (!ff_guidcmp(&stream_type,
                         &ff_asf_ext_stream_embed_stream_header))
        type = AVMEDIA_TYPE_UNKNOWN;
    else
        return AVERROR_INVALIDDATA;

    ff_get_guid(pb, &stream_type); // error correction type
    avio_skip(pb, 8); // skip the time offset
    ts_data_len      = avio_rl32(pb);
    err_data_len     = avio_rl32(pb);
    flags            = avio_rl16(pb); // bit 15 - Encrypted Content

    stream_index = flags & ASF_STREAM_NUM;
    for (i = 0; i < asf->nb_streams; i++)
        if (stream_index == asf->asf_st[i]->stream_index) {
            av_log(s, AV_LOG_WARNING,
                   "Duplicate stream found, this stream will be ignored.\n");
            align_position(pb, asf->offset, size);
            return 0;
        }

    st = avformat_new_stream(s, NULL);
    if (!st)
        return AVERROR(ENOMEM);
    avpriv_set_pts_info(st, 32, 1, 1000); // pts should be dword, in milliseconds
    st->codecpar->codec_type = type;
    asf->asf_st[asf->nb_streams] = av_mallocz(sizeof(*asf_st));
    if (!asf->asf_st[asf->nb_streams])
        return AVERROR(ENOMEM);
    asf_st                       = asf->asf_st[asf->nb_streams];
    asf->nb_streams++;
    asf_st->stream_index         = stream_index;
    asf_st->index                = st->index;
    asf_st->indexed              = 0;
    st->id                       = flags & ASF_STREAM_NUM;
    av_init_packet(&asf_st->pkt.avpkt);
    asf_st->pkt.data_size        = 0;
    avio_skip(pb, 4); // skip reserved field

    switch (type) {
    case AVMEDIA_TYPE_AUDIO:
        asf_st->type = AVMEDIA_TYPE_AUDIO;
        if ((ret = ff_get_wav_header(s, pb, st->codecpar, ts_data_len, 0)) < 0)
            return ret;
        break;
    case AVMEDIA_TYPE_VIDEO:
        asf_st->type = AVMEDIA_TYPE_VIDEO;
        if ((ret = parse_video_info(pb, st)) < 0)
            return ret;
        break;
    default:
        avio_skip(pb, ts_data_len);
        break;
    }

    if (err_data_len) {
        if (type == AVMEDIA_TYPE_AUDIO) {
            uint8_t span = avio_r8(pb);
            if (span > 1) {
                asf_st->span              = span;
                asf_st->virtual_pkt_len   = avio_rl16(pb);
                asf_st->virtual_chunk_len = avio_rl16(pb);
                if (!asf_st->virtual_chunk_len || !asf_st->virtual_pkt_len)
                    return AVERROR_INVALIDDATA;
                avio_skip(pb, err_data_len - 5);
            } else
                avio_skip(pb, err_data_len - 1);
        } else
            avio_skip(pb, err_data_len);
    }

    align_position(pb, asf->offset, size);

    return 0;
}

static void set_language(AVFormatContext *s, const char *rfc1766, AVDictionary **met)
{
    // language abbr should contain at least 2 chars
    if (rfc1766 && strlen(rfc1766) > 1) {
        const char primary_tag[3] = { rfc1766[0], rfc1766[1], '\0' }; // ignore country code if any
        const char *iso6392       = ff_convert_lang_to(primary_tag,
                                                       AV_LANG_ISO639_2_BIBL);
        if (iso6392)
            if (av_dict_set(met, "language", iso6392, 0) < 0)
                av_log(s, AV_LOG_WARNING, "av_dict_set failed.\n");
    }
}

static int asf_read_ext_stream_properties(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    AVStream *st    = NULL;
    ff_asf_guid guid;
    uint16_t nb_st_name, nb_pay_exts, st_num, lang_idx;
    int i, ret;
    uint32_t bitrate;
    uint64_t start_time, end_time, time_per_frame;
    uint64_t size = avio_rl64(pb);

    start_time = avio_rl64(pb);
    end_time   = avio_rl64(pb);
    bitrate    = avio_rl32(pb);
    avio_skip(pb, 28); // skip some unused values
    st_num     = avio_rl16(pb);
    st_num    &= ASF_STREAM_NUM;
    lang_idx   = avio_rl16(pb); // Stream Language ID Index
    for (i = 0; i < asf->nb_streams; i++) {
        if (st_num == asf->asf_st[i]->stream_index) {
            st                       = s->streams[asf->asf_st[i]->index];
            asf->asf_st[i]->lang_idx = lang_idx;
            break;
        }
    }
    time_per_frame = avio_rl64(pb); // average time per frame
    if (st) {
        st->start_time           = start_time;
        st->duration             = end_time - start_time;
        st->codecpar->bit_rate   = bitrate;
        st->avg_frame_rate.num   = 10000000;
        st->avg_frame_rate.den   = time_per_frame;
    }
    nb_st_name = avio_rl16(pb);
    nb_pay_exts   = avio_rl16(pb);
    for (i = 0; i < nb_st_name; i++) {
        uint16_t len;

        avio_rl16(pb); // Language ID Index
        len = avio_rl16(pb);
        avio_skip(pb, len);
    }

    for (i = 0; i < nb_pay_exts; i++) {
        uint32_t len;
        avio_skip(pb, 16); // Extension System ID
        avio_skip(pb, 2);  // Extension Data Size
        len = avio_rl32(pb);
        avio_skip(pb, len);
    }

    if ((ret = ff_get_guid(pb, &guid)) < 0) {
        align_position(pb, asf->offset, size);

        return 0;
    }

    g = find_guid(guid);
    if (g && !(strcmp(g->name, "Stream Properties"))) {
        if ((ret = g->read_object(s, g)) < 0)
            return ret;
    }

    align_position(pb, asf->offset, size);
    return 0;
}

static int asf_read_language_list(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf   = s->priv_data;
    AVIOContext *pb   = s->pb;
    int i, ret;
    uint64_t size     = avio_rl64(pb);
    uint16_t nb_langs = avio_rl16(pb);

    if (nb_langs < ASF_MAX_STREAMS) {
        for (i = 0; i < nb_langs; i++) {
            size_t len;
            len = avio_r8(pb);
            if (!len)
                len = 6;
            if ((ret = get_asf_string(pb, len, asf->asf_sd[i].langs,
                                      sizeof(asf->asf_sd[i].langs))) < 0) {
                return ret;
            }
        }
    }

    align_position(pb, asf->offset, size);
    return 0;
}

// returns data object offset when reading this object for the first time
static int asf_read_data(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint64_t size   = asf->data_size = avio_rl64(pb);
    int i;

    if (!asf->data_reached) {
        asf->data_reached       = 1;
        asf->data_offset        = asf->offset;
    }

    for (i = 0; i < asf->nb_streams; i++) {
        if (!(asf->b_flags & ASF_FLAG_BROADCAST))
            s->streams[i]->duration = asf->duration;
    }
    asf->nb_mult_left           = 0;
    asf->sub_left               = 0;
    asf->state                  = PARSE_PACKET_HEADER;
    asf->return_subpayload      = 0;
    asf->packet_size_internal   = 0;
    avio_skip(pb, 16); // skip File ID
    size = avio_rl64(pb); // Total Data Packets
    if (size != asf->nb_packets)
        av_log(s, AV_LOG_WARNING,
               "Number of Packets from File Properties Object is not equal to Total"
               "Datapackets value! num of packets %"PRIu64" total num %"PRIu64".\n",
               size, asf->nb_packets);
    avio_skip(pb, 2); // skip reserved field
    asf->first_packet_offset = avio_tell(pb);
    if ((pb->seekable & AVIO_SEEKABLE_NORMAL) && !(asf->b_flags & ASF_FLAG_BROADCAST))
        align_position(pb, asf->offset, asf->data_size);

    return 0;
}

static int asf_read_simple_index(AVFormatContext *s, const GUIDParseTable *g)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    AVStream *st    = NULL;
    uint64_t interval; // index entry time interval in 100 ns units, usually it's 1s
    uint32_t pkt_num, nb_entries;
    int32_t prev_pkt_num = -1;
    int i;
    int64_t offset;
    uint64_t size = avio_rl64(pb);

    // simple index objects should be ordered by stream number, this loop tries to find
    // the first not indexed video stream
    for (i = 0; i < asf->nb_streams; i++) {
        if ((asf->asf_st[i]->type == AVMEDIA_TYPE_VIDEO) && !asf->asf_st[i]->indexed) {
            asf->asf_st[i]->indexed = 1;
            st = s->streams[asf->asf_st[i]->index];
            break;
        }
    }
    if (!st) {
        avio_skip(pb, size - 24); // if there's no video stream, skip index object
        return 0;
    }
    avio_skip(pb, 16); // skip File ID
    interval = avio_rl64(pb);
    avio_skip(pb, 4);
    nb_entries = avio_rl32(pb);
    for (i = 0; i < nb_entries; i++) {
        pkt_num = avio_rl32(pb);
        offset = avio_skip(pb, 2);
        if (offset < 0) {
            av_log(s, AV_LOG_ERROR, "Skipping failed in asf_read_simple_index.\n");
            return offset;
        }
        if (prev_pkt_num != pkt_num) {
            av_add_index_entry(st, asf->first_packet_offset + asf->packet_size *
                               pkt_num, av_rescale(interval, i, 10000),
                               asf->packet_size, 0, AVINDEX_KEYFRAME);
            prev_pkt_num = pkt_num;
        }
    }
    asf->is_simple_index = 1;
    align_position(pb, asf->offset, size);

    return 0;
}

static const GUIDParseTable gdef[] = {
    { "Data",                         { 0x75, 0xB2, 0x26, 0x36, 0x66, 0x8E, 0x11, 0xCF, 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C }, asf_read_data, 1 },
    { "Simple Index",                 { 0x33, 0x00, 0x08, 0x90, 0xE5, 0xB1, 0x11, 0xCF, 0x89, 0xF4, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xCB }, asf_read_simple_index, 1 },
    { "Content Description",          { 0x75, 0xB2, 0x26, 0x33, 0x66 ,0x8E, 0x11, 0xCF, 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C }, asf_read_content_desc, 1 },
    { "Extended Content Description", { 0xD2, 0xD0, 0xA4, 0x40, 0xE3, 0x07, 0x11, 0xD2, 0x97, 0xF0, 0x00, 0xA0, 0xC9, 0x5e, 0xA8, 0x50 }, asf_read_ext_content, 1 },
    { "Stream Bitrate Properties",    { 0x7B, 0xF8, 0x75, 0xCE, 0x46, 0x8D, 0x11, 0xD1, 0x8D, 0x82, 0x00, 0x60, 0x97, 0xC9, 0xA2, 0xB2 }, asf_read_unknown, 1 },
    { "File Properties",              { 0x8C, 0xAB, 0xDC, 0xA1, 0xA9, 0x47, 0x11, 0xCF, 0x8E, 0xE4, 0x00, 0xC0, 0x0C, 0x20, 0x53, 0x65 }, asf_read_properties, 1 },
    { "Header Extension",             { 0x5F, 0xBF, 0x03, 0xB5, 0xA9, 0x2E, 0x11, 0xCF, 0x8E, 0xE3, 0x00, 0xC0, 0x0C, 0x20, 0x53, 0x65 }, asf_read_unknown, 0 },
    { "Stream Properties",            { 0xB7, 0xDC, 0x07, 0x91, 0xA9, 0xB7, 0x11, 0xCF, 0x8E, 0xE6, 0x00, 0xC0, 0x0C, 0x20, 0x53, 0x65 }, asf_read_stream_properties, 1 },
    { "Codec List",                   { 0x86, 0xD1, 0x52, 0x40, 0x31, 0x1D, 0x11, 0xD0, 0xA3, 0xA4, 0x00, 0xA0, 0xC9, 0x03, 0x48, 0xF6 }, asf_read_unknown, 1 },
    { "Marker",                       { 0xF4, 0x87, 0xCD, 0x01, 0xA9, 0x51, 0x11, 0xCF, 0x8E, 0xE6, 0x00, 0xC0, 0x0C, 0x20, 0x53, 0x65 }, asf_read_marker, 1 },
    { "Script Command",               { 0x1E, 0xFB, 0x1A, 0x30, 0x0B, 0x62, 0x11, 0xD0, 0xA3, 0x9B, 0x00, 0xA0, 0xC9, 0x03, 0x48, 0xF6 }, asf_read_unknown, 1 },
    { "Language List",                { 0x7C, 0x43, 0x46, 0xa9, 0xef, 0xe0, 0x4B, 0xFC, 0xB2, 0x29, 0x39, 0x3e, 0xde, 0x41, 0x5c, 0x85 }, asf_read_language_list, 1},
    { "Padding",                      { 0x18, 0x06, 0xD4, 0x74, 0xCA, 0xDF, 0x45, 0x09, 0xA4, 0xBA, 0x9A, 0xAB, 0xCB, 0x96, 0xAA, 0xE8 }, asf_read_unknown, 1 },
    { "DRMv1 Header",                 { 0x22, 0x11, 0xB3, 0xFB, 0xBD, 0x23, 0x11, 0xD2, 0xB4, 0xB7, 0x00, 0xA0, 0xC9, 0x55, 0xFC, 0x6E }, asf_read_unknown, 1 },
    { "DRMv2 Header",                 { 0x29, 0x8A, 0xE6, 0x14, 0x26, 0x22, 0x4C, 0x17, 0xB9, 0x35, 0xDA, 0xE0, 0x7E, 0xE9, 0x28, 0x9c }, asf_read_unknown, 1 },
    { "Index",                        { 0xD6, 0xE2, 0x29, 0xD3, 0x35, 0xDA, 0x11, 0xD1, 0x90, 0x34, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xBE }, asf_read_unknown, 1 },
    { "Media Object Index",           { 0xFE, 0xB1, 0x03, 0xF8, 0x12, 0xAD, 0x4C, 0x64, 0x84, 0x0F, 0x2A, 0x1D, 0x2F, 0x7A, 0xD4, 0x8C }, asf_read_unknown, 1 },
    { "Timecode Index",               { 0x3C, 0xB7, 0x3F, 0xD0, 0x0C, 0x4A, 0x48, 0x03, 0x95, 0x3D, 0xED, 0xF7, 0xB6, 0x22, 0x8F, 0x0C }, asf_read_unknown, 0 },
    { "Bitrate_Mutual_Exclusion",     { 0xD6, 0xE2, 0x29, 0xDC, 0x35, 0xDA, 0x11, 0xD1, 0x90, 0x34, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xBE }, asf_read_unknown, 1 },
    { "Error Correction",             { 0x75, 0xB2, 0x26, 0x35, 0x66, 0x8E, 0x11, 0xCF, 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C }, asf_read_unknown, 1 },
    { "Content Branding",             { 0x22, 0x11, 0xB3, 0xFA, 0xBD, 0x23, 0x11, 0xD2, 0xB4, 0xB7, 0x00, 0xA0, 0xC9, 0x55, 0xFC, 0x6E }, asf_read_unknown, 1 },
    { "Content Encryption",           { 0x22, 0x11, 0xB3, 0xFB, 0xBD, 0x23, 0x11, 0xD2, 0xB4, 0xB7, 0x00, 0xA0, 0xC9, 0x55, 0xFC, 0x6E }, asf_read_unknown, 1 },
    { "Extended Content Encryption",  { 0x29, 0x8A, 0xE6, 0x14, 0x26, 0x22, 0x4C, 0x17, 0xB9, 0x35, 0xDA, 0xE0, 0x7E, 0xE9, 0x28, 0x9C }, asf_read_unknown, 1 },
    { "Digital Signature",            { 0x22, 0x11, 0xB3, 0xFC, 0xBD, 0x23, 0x11, 0xD2, 0xB4, 0xB7, 0x00, 0xA0, 0xC9, 0x55, 0xFC, 0x6E }, asf_read_unknown, 1 },
    { "Extended Stream Properties",   { 0x14, 0xE6, 0xA5, 0xCB, 0xC6, 0x72, 0x43, 0x32, 0x83, 0x99, 0xA9, 0x69, 0x52, 0x06, 0x5B, 0x5A }, asf_read_ext_stream_properties, 1 },
    { "Advanced Mutual Exclusion",    { 0xA0, 0x86, 0x49, 0xCF, 0x47, 0x75, 0x46, 0x70, 0x8A, 0x16, 0x6E, 0x35, 0x35, 0x75, 0x66, 0xCD }, asf_read_unknown, 1 },
    { "Group Mutual Exclusion",       { 0xD1, 0x46, 0x5A, 0x40, 0x5A, 0x79, 0x43, 0x38, 0xB7, 0x1B, 0xE3, 0x6B, 0x8F, 0xD6, 0xC2, 0x49 }, asf_read_unknown, 1},
    { "Stream Prioritization",        { 0xD4, 0xFE, 0xD1, 0x5B, 0x88, 0xD3, 0x45, 0x4F, 0x81, 0xF0, 0xED, 0x5C, 0x45, 0x99, 0x9E, 0x24 }, asf_read_unknown, 1 },
    { "Bandwidth Sharing Object",     { 0xA6, 0x96, 0x09, 0xE6, 0x51, 0x7B, 0x11, 0xD2, 0xB6, 0xAF, 0x00, 0xC0, 0x4F, 0xD9, 0x08, 0xE9 }, asf_read_unknown, 1 },
    { "Metadata",                     { 0xC5, 0xF8, 0xCB, 0xEA, 0x5B, 0xAF, 0x48, 0x77, 0x84, 0x67, 0xAA, 0x8C, 0x44, 0xFA, 0x4C, 0xCA }, asf_read_metadata_obj, 1 },
    { "Metadata Library",             { 0x44, 0x23, 0x1C, 0x94, 0x94, 0x98, 0x49, 0xD1, 0xA1, 0x41, 0x1D, 0x13, 0x4E, 0x45, 0x70, 0x54 }, asf_read_metadata_obj, 1 },
    { "Audio Spread",                 { 0xBF, 0xC3, 0xCD, 0x50, 0x61, 0x8F, 0x11, 0xCF, 0x8B, 0xB2, 0x00, 0xAA, 0x00, 0xB4, 0xE2, 0x20 }, asf_read_unknown, 1 },
    { "Index Parameters",             { 0xD6, 0xE2, 0x29, 0xDF, 0x35, 0xDA, 0x11, 0xD1, 0x90, 0x34, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xBE }, asf_read_unknown, 1 },
    { "Content Encryption System Windows Media DRM Network Devices",
                                      { 0x7A, 0x07, 0x9B, 0xB6, 0xDA, 0XA4, 0x4e, 0x12, 0xA5, 0xCA, 0x91, 0xD3, 0x8D, 0xC1, 0x1A, 0x8D }, asf_read_unknown, 1 },
    { "Mutex Language",               { 0xD6, 0xE2, 0x2A, 0x00, 0x25, 0xDA, 0x11, 0xD1, 0x90, 0x34, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xBE }, asf_read_unknown, 1 },
    { "Mutex Bitrate",                { 0xD6, 0xE2, 0x2A, 0x01, 0x25, 0xDA, 0x11, 0xD1, 0x90, 0x34, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xBE }, asf_read_unknown, 1 },
    { "Mutex Unknown",                { 0xD6, 0xE2, 0x2A, 0x02, 0x25, 0xDA, 0x11, 0xD1, 0x90, 0x34, 0x00, 0xA0, 0xC9, 0x03, 0x49, 0xBE }, asf_read_unknown, 1 },
    { "Bandwidth Sharing Exclusive",  { 0xAF, 0x60, 0x60, 0xAA, 0x51, 0x97, 0x11, 0xD2, 0xB6, 0xAF, 0x00, 0xC0, 0x4F, 0xD9, 0x08, 0xE9 }, asf_read_unknown, 1 },
    { "Bandwidth Sharing Partial",    { 0xAF, 0x60, 0x60, 0xAB, 0x51, 0x97, 0x11, 0xD2, 0xB6, 0xAF, 0x00, 0xC0, 0x4F, 0xD9, 0x08, 0xE9 }, asf_read_unknown, 1 },
    { "Payload Extension System Timecode", { 0x39, 0x95, 0x95, 0xEC, 0x86, 0x67, 0x4E, 0x2D, 0x8F, 0xDB, 0x98, 0x81, 0x4C, 0xE7, 0x6C, 0x1E }, asf_read_unknown, 1 },
    { "Payload Extension System File Name", { 0xE1, 0x65, 0xEC, 0x0E, 0x19, 0xED, 0x45, 0xD7, 0xB4, 0xA7, 0x25, 0xCB, 0xD1, 0xE2, 0x8E, 0x9B }, asf_read_unknown, 1 },
    { "Payload Extension System Content Type", { 0xD5, 0x90, 0xDC, 0x20, 0x07, 0xBC, 0x43, 0x6C, 0x9C, 0xF7, 0xF3, 0xBB, 0xFB, 0xF1, 0xA4, 0xDC }, asf_read_unknown, 1 },
    { "Payload Extension System Pixel Aspect Ratio", { 0x1, 0x1E, 0xE5, 0x54, 0xF9, 0xEA, 0x4B, 0xC8, 0x82, 0x1A, 0x37, 0x6B, 0x74, 0xE4, 0xC4, 0xB8 }, asf_read_unknown, 1 },
    { "Payload Extension System Sample Duration", { 0xC6, 0xBD, 0x94, 0x50, 0x86, 0x7F, 0x49, 0x07, 0x83, 0xA3, 0xC7, 0x79, 0x21, 0xB7, 0x33, 0xAD }, asf_read_unknown, 1 },
    { "Payload Extension System Encryption Sample ID", { 0x66, 0x98, 0xB8, 0x4E, 0x0A, 0xFA, 0x43, 0x30, 0xAE, 0xB2, 0x1C, 0x0A, 0x98, 0xD7, 0xA4, 0x4D }, asf_read_unknown, 1 },
    { "Payload Extension System Degradable JPEG", { 0x00, 0xE1, 0xAF, 0x06, 0x7B, 0xEC, 0x11, 0xD1, 0xA5, 0x82, 0x00, 0xC0, 0x4F, 0xC2, 0x9C, 0xFB }, asf_read_unknown, 1 },
};

#define READ_LEN(flag, name, len)            \
    do {                                     \
        if ((flag) == name ## IS_BYTE)       \
            len = avio_r8(pb);               \
        else if ((flag) == name ## IS_WORD)  \
            len = avio_rl16(pb);             \
        else if ((flag) == name ## IS_DWORD) \
            len = avio_rl32(pb);             \
        else                                 \
            len = 0;                         \
    } while(0)

static int asf_read_subpayload(AVFormatContext *s, AVPacket *pkt, int is_header)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint8_t sub_len;
    int ret, i;

    if (is_header) {
        asf->dts_delta = avio_r8(pb);
        if (asf->nb_mult_left) {
            asf->mult_sub_len = avio_rl16(pb); // total
        }
        asf->sub_header_offset = avio_tell(pb);
        asf->nb_sub = 0;
        asf->sub_left = 1;
    }
    sub_len = avio_r8(pb);
    if ((ret = av_get_packet(pb, pkt, sub_len)) < 0) // each subpayload is entire frame
        return ret;
    for (i = 0; i < asf->nb_streams; i++) {
        if (asf->stream_index == asf->asf_st[i]->stream_index) {
            pkt->stream_index  = asf->asf_st[i]->index;
            break;
        }
    }
    asf->return_subpayload = 1;
    if (!sub_len)
        asf->return_subpayload = 0;

    if (sub_len)
        asf->nb_sub++;
    pkt->dts = asf->sub_dts + (asf->nb_sub - 1) * asf->dts_delta - asf->preroll;
    if (asf->nb_mult_left && (avio_tell(pb) >=
                              (asf->sub_header_offset + asf->mult_sub_len))) {
        asf->sub_left = 0;
        asf->nb_mult_left--;
    }
    if (avio_tell(pb) >= asf->packet_offset + asf->packet_size - asf->pad_len) {
        asf->sub_left = 0;
        if (!asf->nb_mult_left) {
            avio_skip(pb, asf->pad_len);
            if (avio_tell(pb) != asf->packet_offset + asf->packet_size) {
                if (!asf->packet_size)
                    return AVERROR_INVALIDDATA;
                av_log(s, AV_LOG_WARNING,
                       "Position %"PRId64" wrong, should be %"PRId64"\n",
                       avio_tell(pb), asf->packet_offset + asf->packet_size);
                avio_seek(pb, asf->packet_offset + asf->packet_size, SEEK_SET);
            }
        }
    }

    return 0;
}

static void reset_packet(ASFPacket *asf_pkt)
{
    asf_pkt->size_left = 0;
    asf_pkt->data_size = 0;
    asf_pkt->duration  = 0;
    asf_pkt->flags     = 0;
    asf_pkt->dts       = 0;
    asf_pkt->duration  = 0;
    av_packet_unref(&asf_pkt->avpkt);
    av_init_packet(&asf_pkt->avpkt);
}

static int asf_read_replicated_data(AVFormatContext *s, ASFPacket *asf_pkt)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    int ret, data_size;

    if (!asf_pkt->data_size) {
        data_size = avio_rl32(pb); // read media object size
        if (data_size <= 0)
            return AVERROR_INVALIDDATA;
        if ((ret = av_new_packet(&asf_pkt->avpkt, data_size)) < 0)
            return ret;
        asf_pkt->data_size = asf_pkt->size_left = data_size;
    } else
        avio_skip(pb, 4); // reading of media object size is already done
    asf_pkt->dts = avio_rl32(pb); // read presentation time
    if (asf->rep_data_len && (asf->rep_data_len >= 8))
        avio_skip(pb, asf->rep_data_len - 8); // skip replicated data

    return 0;
}

static int asf_read_multiple_payload(AVFormatContext *s, AVPacket *pkt,
                                 ASFPacket *asf_pkt)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint16_t pay_len;
    unsigned char *p;
    int ret;
    int skip = 0;

    // if replicated length is 1, subpayloads are present
    if (asf->rep_data_len == 1) {
        asf->sub_left = 1;
        asf->state = READ_MULTI_SUB;
        pkt->flags = asf_pkt->flags;
        if ((ret = asf_read_subpayload(s, pkt, 1)) < 0)
            return ret;
    } else {
        if (asf->rep_data_len)
            if ((ret = asf_read_replicated_data(s, asf_pkt)) < 0)
                return ret;
        pay_len = avio_rl16(pb); // payload length should be WORD
        if (pay_len > asf->packet_size) {
            av_log(s, AV_LOG_ERROR,
                   "Error: invalid data packet size, pay_len %"PRIu16", "
                   "asf->packet_size %"PRIu32", offset %"PRId64".\n",
                   pay_len, asf->packet_size, avio_tell(pb));
            return AVERROR_INVALIDDATA;
        }
        p = asf_pkt->avpkt.data + asf_pkt->data_size - asf_pkt->size_left;
        if (pay_len > asf_pkt->size_left) {
            av_log(s, AV_LOG_ERROR,
                   "Error: invalid buffer size, pay_len %d, data size left %d.\n",
            pay_len, asf_pkt->size_left);
            skip = pay_len - asf_pkt->size_left;
            pay_len = asf_pkt->size_left;
        }
        if (asf_pkt->size_left <= 0)
            return AVERROR_INVALIDDATA;
        if ((ret = avio_read(pb, p, pay_len)) < 0)
            return ret;
        if (s->key && s->keylen == 20)
            ff_asfcrypt_dec(s->key, p, ret);
        avio_skip(pb, skip);
        asf_pkt->size_left -= pay_len;
        asf->nb_mult_left--;
    }

    return 0;
}

static int asf_read_single_payload(AVFormatContext *s, ASFPacket *asf_pkt)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    int64_t  offset;
    uint64_t size;
    unsigned char *p;
    int ret, data_size;

    if (!asf_pkt->data_size) {
        data_size = avio_rl32(pb); // read media object size
        if (data_size <= 0)
            return AVERROR_EOF;
        if ((ret = av_new_packet(&asf_pkt->avpkt, data_size)) < 0)
            return ret;
        asf_pkt->data_size = asf_pkt->size_left = data_size;
    } else
        avio_skip(pb, 4); // skip media object size
    asf_pkt->dts = avio_rl32(pb); // read presentation time
    if (asf->rep_data_len >= 8)
        avio_skip(pb, asf->rep_data_len - 8); // skip replicated data
    offset = avio_tell(pb);

    // size of the payload - size of the packet without header and padding
    if (asf->packet_size_internal)
        size = asf->packet_size_internal - offset + asf->packet_offset - asf->pad_len;
    else
        size = asf->packet_size - offset + asf->packet_offset - asf->pad_len;
    if (size > asf->packet_size) {
        av_log(s, AV_LOG_ERROR,
               "Error: invalid data packet size, offset %"PRId64".\n",
               avio_tell(pb));
        return AVERROR_INVALIDDATA;
    }
    p = asf_pkt->avpkt.data + asf_pkt->data_size - asf_pkt->size_left;
    if (size > asf_pkt->size_left || asf_pkt->size_left <= 0)
        return AVERROR_INVALIDDATA;
    if (asf_pkt->size_left > size)
        asf_pkt->size_left -= size;
    else
        asf_pkt->size_left = 0;
    if ((ret = avio_read(pb, p, size)) < 0)
        return ret;
    if (s->key && s->keylen == 20)
            ff_asfcrypt_dec(s->key, p, ret);
    if (asf->packet_size_internal)
        avio_skip(pb, asf->packet_size - asf->packet_size_internal);
    avio_skip(pb, asf->pad_len); // skip padding

    return 0;
}

static int asf_read_payload(AVFormatContext *s, AVPacket *pkt)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    int ret, i;
    ASFPacket *asf_pkt = NULL;

    if (!asf->sub_left) {
        uint32_t off_len, media_len;
        uint8_t stream_num;

        stream_num = avio_r8(pb);
        asf->stream_index = stream_num & ASF_STREAM_NUM;
        for (i = 0; i < asf->nb_streams; i++) {
            if (asf->stream_index == asf->asf_st[i]->stream_index) {
                asf_pkt               = &asf->asf_st[i]->pkt;
                asf_pkt->stream_index = asf->asf_st[i]->index;
                break;
            }
        }
        if (!asf_pkt) {
            if (asf->packet_offset + asf->packet_size <= asf->data_offset + asf->data_size) {
                if (!asf->packet_size) {
                    av_log(s, AV_LOG_ERROR, "Invalid packet size 0.\n");
                    return AVERROR_INVALIDDATA;
                }
                avio_seek(pb, asf->packet_offset + asf->packet_size, SEEK_SET);
                av_log(s, AV_LOG_WARNING, "Skipping the stream with the invalid stream index %d.\n",
                       asf->stream_index);
                return AVERROR(EAGAIN);
            } else
                return AVERROR_INVALIDDATA;
        }

        if (stream_num >> 7)
            asf_pkt->flags |= AV_PKT_FLAG_KEY;
        READ_LEN(asf->prop_flags & ASF_PL_MASK_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_SIZE,
                 ASF_PL_FLAG_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_, media_len);
        READ_LEN(asf->prop_flags & ASF_PL_MASK_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_SIZE,
                 ASF_PL_FLAG_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_, off_len);
        READ_LEN(asf->prop_flags & ASF_PL_MASK_REPLICATED_DATA_LENGTH_FIELD_SIZE,
                 ASF_PL_FLAG_REPLICATED_DATA_LENGTH_FIELD_, asf->rep_data_len);
        if (asf_pkt->size_left && (asf_pkt->frame_num != media_len)) {
            av_log(s, AV_LOG_WARNING, "Unfinished frame will be ignored\n");
            reset_packet(asf_pkt);
        }
        asf_pkt->frame_num = media_len;
        asf->sub_dts = off_len;
        if (asf->nb_mult_left) {
            if ((ret = asf_read_multiple_payload(s, pkt, asf_pkt)) < 0)
                return ret;
        } else if (asf->rep_data_len == 1) {
            asf->sub_left = 1;
            asf->state    = READ_SINGLE;
            pkt->flags    = asf_pkt->flags;
            if ((ret = asf_read_subpayload(s, pkt, 1)) < 0)
                return ret;
        } else {
            if ((ret = asf_read_single_payload(s, asf_pkt)) < 0)
                return ret;
        }
    } else {
        for (i = 0; i <= asf->nb_streams; i++) {
            if (asf->stream_index == asf->asf_st[i]->stream_index) {
                asf_pkt = &asf->asf_st[i]->pkt;
                break;
            }
        }
        if (!asf_pkt)
            return AVERROR_INVALIDDATA;
        pkt->flags         = asf_pkt->flags;
        pkt->dts           = asf_pkt->dts;
        pkt->stream_index  = asf->asf_st[i]->index;
        if ((ret = asf_read_subpayload(s, pkt, 0)) < 0) // read subpayload without its header
            return ret;
    }

    return 0;
}

static int asf_read_packet_header(AVFormatContext *s)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    uint64_t size;
    uint32_t av_unused seq;
    unsigned char error_flags, len_flags, pay_flags;

    asf->packet_offset = avio_tell(pb);
    error_flags = avio_r8(pb); // read Error Correction Flags
    if (error_flags & ASF_PACKET_FLAG_ERROR_CORRECTION_PRESENT) {
        if (!(error_flags & ASF_ERROR_CORRECTION_LENGTH_TYPE)) {
            size = error_flags & ASF_PACKET_ERROR_CORRECTION_DATA_SIZE;
            avio_skip(pb, size);
        }
        len_flags       = avio_r8(pb);
    } else
        len_flags = error_flags;
    asf->prop_flags = avio_r8(pb);
    READ_LEN(len_flags & ASF_PPI_MASK_PACKET_LENGTH_FIELD_SIZE,
             ASF_PPI_FLAG_PACKET_LENGTH_FIELD_, asf->packet_size_internal);
    READ_LEN(len_flags & ASF_PPI_MASK_SEQUENCE_FIELD_SIZE,
             ASF_PPI_FLAG_SEQUENCE_FIELD_, seq);
    READ_LEN(len_flags & ASF_PPI_MASK_PADDING_LENGTH_FIELD_SIZE,
             ASF_PPI_FLAG_PADDING_LENGTH_FIELD_, asf->pad_len );
    asf->send_time = avio_rl32(pb); // send time
    avio_skip(pb, 2); // skip duration
    if (len_flags & ASF_PPI_FLAG_MULTIPLE_PAYLOADS_PRESENT) { // Multiple Payloads present
        pay_flags = avio_r8(pb);
        asf->nb_mult_left = (pay_flags & ASF_NUM_OF_PAYLOADS);
    }

    return 0;
}

static int asf_deinterleave(AVFormatContext *s, ASFPacket *asf_pkt, int st_num)
{
    ASFContext *asf    = s->priv_data;
    ASFStream *asf_st  = asf->asf_st[st_num];
    unsigned char *p   = asf_pkt->avpkt.data;
    uint16_t pkt_len   = asf->asf_st[st_num]->virtual_pkt_len;
    uint16_t chunk_len = asf->asf_st[st_num]->virtual_chunk_len;
    int nchunks        = pkt_len / chunk_len;
    AVPacket pkt;
    int pos = 0, j, l, ret;


    if ((ret = av_new_packet(&pkt, asf_pkt->data_size)) < 0)
        return ret;

    while (asf_pkt->data_size >= asf_st->span * pkt_len + pos) {
        if (pos >= asf_pkt->data_size) {
            break;
        }
        for (l = 0; l < pkt_len; l++) {
            if (pos >= asf_pkt->data_size) {
                break;
            }
            for (j = 0; j < asf_st->span; j++) {
                if ((pos + chunk_len) >= asf_pkt->data_size)
                    break;
                memcpy(pkt.data + pos,
                       p + (j * nchunks + l) * chunk_len,
                       chunk_len);
                pos += chunk_len;
            }
        }
        p += asf_st->span * pkt_len;
        if (p > asf_pkt->avpkt.data + asf_pkt->data_size)
            break;
    }
    av_packet_unref(&asf_pkt->avpkt);
    asf_pkt->avpkt = pkt;

    return 0;
}

static int asf_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    int ret, i;

    if ((avio_tell(pb) >= asf->data_offset + asf->data_size) &&
        !(asf->b_flags & ASF_FLAG_BROADCAST))
        return AVERROR_EOF;
    while (!pb->eof_reached) {
        if (asf->state == PARSE_PACKET_HEADER) {
            asf_read_packet_header(s);
            if (pb->eof_reached)
                break;
            if (!asf->nb_mult_left)
                asf->state = READ_SINGLE;
            else
                asf->state = READ_MULTI;
        }
        ret = asf_read_payload(s, pkt);
        if (ret == AVERROR(EAGAIN)) {
            asf->state = PARSE_PACKET_HEADER;
            continue;
        }
        else if (ret < 0)
            return ret;

        switch (asf->state) {
        case READ_SINGLE:
            if (!asf->sub_left)
                asf->state = PARSE_PACKET_HEADER;
            break;
        case READ_MULTI_SUB:
            if (!asf->sub_left && !asf->nb_mult_left) {
                asf->state = PARSE_PACKET_HEADER;
                if (!asf->return_subpayload &&
                    (avio_tell(pb) <= asf->packet_offset +
                     asf->packet_size - asf->pad_len))
                    avio_skip(pb, asf->pad_len); // skip padding
                if (asf->packet_offset + asf->packet_size > avio_tell(pb))
                    avio_seek(pb, asf->packet_offset + asf->packet_size, SEEK_SET);
            } else if (!asf->sub_left)
                asf->state = READ_MULTI;
            break;
        case READ_MULTI:
            if (!asf->nb_mult_left) {
                asf->state = PARSE_PACKET_HEADER;
                if (!asf->return_subpayload &&
                    (avio_tell(pb) <= asf->packet_offset +
                     asf->packet_size - asf->pad_len))
                    avio_skip(pb, asf->pad_len); // skip padding
                if (asf->packet_offset + asf->packet_size > avio_tell(pb))
                    avio_seek(pb, asf->packet_offset + asf->packet_size, SEEK_SET);
            }
            break;
        }
        if (asf->return_subpayload) {
            asf->return_subpayload = 0;
            return 0;
        }
        for (i = 0; i < asf->nb_streams; i++) {
            ASFPacket *asf_pkt = &asf->asf_st[i]->pkt;
            if (asf_pkt && !asf_pkt->size_left && asf_pkt->data_size) {
                if (asf->asf_st[i]->span > 1 &&
                    asf->asf_st[i]->type == AVMEDIA_TYPE_AUDIO)
                    if ((ret = asf_deinterleave(s, asf_pkt, i)) < 0)
                        return ret;
                av_packet_move_ref(pkt, &asf_pkt->avpkt);
                pkt->stream_index  = asf->asf_st[i]->index;
                pkt->flags         = asf_pkt->flags;
                pkt->dts           = asf_pkt->dts - asf->preroll;
                asf_pkt->data_size = 0;
                asf_pkt->frame_num = 0;
                return 0;
            }
        }
    }

    if (pb->eof_reached)
        return AVERROR_EOF;

    return 0;
}

static int asf_read_close(AVFormatContext *s)
{
    ASFContext *asf = s->priv_data;
    int i;

    for (i = 0; i < ASF_MAX_STREAMS; i++) {
        av_dict_free(&asf->asf_sd[i].asf_met);
        if (i < asf->nb_streams) {
            av_packet_unref(&asf->asf_st[i]->pkt.avpkt);
            av_freep(&asf->asf_st[i]);
        }
    }

    asf->nb_streams = 0;
    return 0;
}

static void reset_packet_state(AVFormatContext *s)
{
    ASFContext *asf        = s->priv_data;
    int i;

    asf->state             = PARSE_PACKET_HEADER;
    asf->offset            = 0;
    asf->return_subpayload = 0;
    asf->sub_left          = 0;
    asf->sub_header_offset = 0;
    asf->packet_offset     = asf->first_packet_offset;
    asf->pad_len           = 0;
    asf->rep_data_len      = 0;
    asf->dts_delta         = 0;
    asf->mult_sub_len      = 0;
    asf->nb_mult_left      = 0;
    asf->nb_sub            = 0;
    asf->prop_flags        = 0;
    asf->sub_dts           = 0;
    for (i = 0; i < asf->nb_streams; i++) {
        ASFPacket *pkt = &asf->asf_st[i]->pkt;
        pkt->size_left = 0;
        pkt->data_size = 0;
        pkt->duration  = 0;
        pkt->flags     = 0;
        pkt->dts       = 0;
        pkt->duration  = 0;
        av_packet_unref(&pkt->avpkt);
        av_init_packet(&pkt->avpkt);
    }
}

/*
 * Find a timestamp for the requested position within the payload
 * where the pos (position) is the offset inside the Data Object.
 * When position is not on the packet boundary, asf_read_timestamp tries
 * to find the closest packet offset after this position. If this packet
 * is a key frame, this packet timestamp is read and an index entry is created
 * for the packet. If this packet belongs to the requested stream,
 * asf_read_timestamp upgrades pos to the packet beginning offset and
 * returns this packet's dts. So returned dts is the dts of the first key frame with
 * matching stream number after given position.
 */
static int64_t asf_read_timestamp(AVFormatContext *s, int stream_index,
                                  int64_t *pos, int64_t pos_limit)
{
    ASFContext *asf = s->priv_data;
    int64_t pkt_pos = *pos, pkt_offset, dts = AV_NOPTS_VALUE, data_end;
    AVPacket pkt;
    int n;

    data_end = asf->data_offset + asf->data_size;

    n = (pkt_pos - asf->first_packet_offset + asf->packet_size - 1) /
        asf->packet_size;
    n = av_clip(n, 0, ((data_end - asf->first_packet_offset) / asf->packet_size - 1));
    pkt_pos = asf->first_packet_offset +  n * asf->packet_size;

    avio_seek(s->pb, pkt_pos, SEEK_SET);
    pkt_offset = pkt_pos;

    reset_packet_state(s);
    while (avio_tell(s->pb) < data_end) {

        int i, ret, st_found;

        av_init_packet(&pkt);
        pkt_offset = avio_tell(s->pb);
        if ((ret = asf_read_packet(s, &pkt)) < 0) {
            dts = AV_NOPTS_VALUE;
            return ret;
        }
        // ASFPacket may contain fragments of packets belonging to different streams,
        // pkt_offset is the offset of the first fragment within it.
        if ((pkt_offset >= (pkt_pos + asf->packet_size)))
            pkt_pos += asf->packet_size;
        for (i = 0; i < asf->nb_streams; i++) {
            ASFStream *st = asf->asf_st[i];

            st_found = 0;
            if (pkt.flags & AV_PKT_FLAG_KEY) {
                dts = pkt.dts;
                if (dts) {
                    av_add_index_entry(s->streams[pkt.stream_index], pkt_pos,
                                       dts, pkt.size, 0, AVINDEX_KEYFRAME);
                    if (stream_index == st->index) {
                        st_found = 1;
                        break;
                    }
                }
            }
        }
        if (st_found)
            break;
        av_packet_unref(&pkt);
    }
    *pos = pkt_pos;

    av_packet_unref(&pkt);
    return dts;
}

static int asf_read_seek(AVFormatContext *s, int stream_index,
                         int64_t timestamp, int flags)
{
    ASFContext *asf = s->priv_data;
    int idx, ret;

    if (s->streams[stream_index]->nb_index_entries && asf->is_simple_index) {
        idx = av_index_search_timestamp(s->streams[stream_index], timestamp, flags);
        if (idx < 0 || idx >= s->streams[stream_index]->nb_index_entries)
            return AVERROR_INVALIDDATA;
        avio_seek(s->pb, s->streams[stream_index]->index_entries[idx].pos, SEEK_SET);
    } else {
        if ((ret = ff_seek_frame_binary(s, stream_index, timestamp, flags)) < 0)
            return ret;
    }

    reset_packet_state(s);

    return 0;
}

static const GUIDParseTable *find_guid(ff_asf_guid guid)
{
    int j, ret;
    const GUIDParseTable *g;

    swap_guid(guid);
    g = gdef;
    for (j = 0; j < FF_ARRAY_ELEMS(gdef); j++) {
        if (!(ret = memcmp(guid, g->guid, sizeof(g->guid))))
            return g;
        g++;
    }

    return NULL;
}

static int detect_unknown_subobject(AVFormatContext *s, int64_t offset, int64_t size)
{
    ASFContext *asf = s->priv_data;
    AVIOContext *pb = s->pb;
    const GUIDParseTable *g = NULL;
    ff_asf_guid guid;
    int ret;

    while (avio_tell(pb) <= offset + size) {
        if (avio_tell(pb) == asf->offset)
            break;
        asf->offset = avio_tell(pb);
        if ((ret = ff_get_guid(pb, &guid)) < 0)
            return ret;
        g = find_guid(guid);
        if (g) {
            if ((ret = g->read_object(s, g)) < 0)
                return ret;
        } else {
            GUIDParseTable g2;

            g2.name         = "Unknown";
            g2.is_subobject = 1;
            asf_read_unknown(s, &g2);
        }
    }

    return 0;
}

static int asf_read_header(AVFormatContext *s)
{
    ASFContext *asf         = s->priv_data;
    AVIOContext *pb         = s->pb;
    const GUIDParseTable *g = NULL;
    ff_asf_guid guid;
    int i, ret;
    uint64_t size;

    asf->preroll         = 0;
    asf->is_simple_index = 0;
    ff_get_guid(pb, &guid);
    if (ff_guidcmp(&guid, &ff_asf_header))
        return AVERROR_INVALIDDATA;
    avio_skip(pb, 8); // skip header object size
    avio_skip(pb, 6); // skip number of header objects and 2 reserved bytes
    asf->data_reached = 0;

    /* 1  is here instead of pb->eof_reached because (when not streaming), Data are skipped
     * for the first time,
     * Index object is processed and got eof and then seeking back to the Data is performed.
     */
    while (1) {
        // for the cases when object size is invalid
        if (avio_tell(pb) == asf->offset)
            break;
        asf->offset = avio_tell(pb);
        if ((ret = ff_get_guid(pb, &guid)) < 0) {
            if (ret == AVERROR_EOF && asf->data_reached)
                break;
            else
                goto failed;
        }
        g = find_guid(guid);
        if (g) {
            asf->unknown_offset = asf->offset;
            asf->is_header = 1;
            if ((ret = g->read_object(s, g)) < 0)
                goto failed;
        } else {
            size = avio_rl64(pb);
            align_position(pb, asf->offset, size);
        }
        if (asf->data_reached &&
            (!(pb->seekable & AVIO_SEEKABLE_NORMAL) ||
             (asf->b_flags & ASF_FLAG_BROADCAST)))
            break;
    }

    if (!asf->data_reached) {
        av_log(s, AV_LOG_ERROR, "Data Object was not found.\n");
        ret = AVERROR_INVALIDDATA;
        goto failed;
    }
    if (pb->seekable & AVIO_SEEKABLE_NORMAL)
        avio_seek(pb, asf->first_packet_offset, SEEK_SET);

    for (i = 0; i < asf->nb_streams; i++) {
        const char *rfc1766 = asf->asf_sd[asf->asf_st[i]->lang_idx].langs;
        AVStream *st        = s->streams[asf->asf_st[i]->index];
        set_language(s, rfc1766, &st->metadata);
    }

    for (i = 0; i < ASF_MAX_STREAMS; i++) {
        AVStream *st = NULL;

        st = find_stream(s, i);
        if (st) {
            av_dict_copy(&st->metadata, asf->asf_sd[i].asf_met, AV_DICT_IGNORE_SUFFIX);
            if (asf->asf_sd[i].aspect_ratio.num > 0 && asf->asf_sd[i].aspect_ratio.den > 0) {
                st->sample_aspect_ratio.num = asf->asf_sd[i].aspect_ratio.num;
                st->sample_aspect_ratio.den = asf->asf_sd[i].aspect_ratio.den;
            }
        }
    }

    return 0;

failed:
    asf_read_close(s);
    return ret;
}

AVInputFormat ff_asf_o_demuxer = {
    .name           = "asf_o",
    .long_name      = NULL_IF_CONFIG_SMALL("ASF (Advanced / Active Streaming Format)"),
    .priv_data_size = sizeof(ASFContext),
    .read_probe     = asf_probe,
    .read_header    = asf_read_header,
    .read_packet    = asf_read_packet,
    .read_close     = asf_read_close,
    .read_timestamp = asf_read_timestamp,
    .read_seek      = asf_read_seek,
    .flags          = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH,
};