falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
36007 Commits
32 Branches
570MB
Tree: 134aaa79f7
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '134aaa79f7'
${ noResults }
FFmpeg/libavformat/mxfdec.c

1953 lines
72KB
Raw Blame History 

  1. /*

  2.  * MXF demuxer.

  3.  * Copyright (c) 2006 SmartJog S.A., Baptiste Coudurier <baptiste dot coudurier at smartjog dot com>

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

  7.  * FFmpeg is free software; you can redistribute it and/or

  8.  * modify it under the terms of the GNU Lesser General Public

  9.  * License as published by the Free Software Foundation; either

  10.  * version 2.1 of the License, or (at your option) any later version.

  11.  *

  12.  * FFmpeg is distributed in the hope that it will be useful,

  13.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  14.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  15.  * Lesser General Public License for more details.

  16.  *

  17.  * You should have received a copy of the GNU Lesser General Public

  18.  * License along with FFmpeg; if not, write to the Free Software

  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  20.  */

  21. 

  22. /*

  23.  * References

  24.  * SMPTE 336M KLV Data Encoding Protocol Using Key-Length-Value

  25.  * SMPTE 377M MXF File Format Specifications

  26.  * SMPTE 378M Operational Pattern 1a

  27.  * SMPTE 379M MXF Generic Container

  28.  * SMPTE 381M Mapping MPEG Streams into the MXF Generic Container

  29.  * SMPTE 382M Mapping AES3 and Broadcast Wave Audio into the MXF Generic Container

  30.  * SMPTE 383M Mapping DV-DIF Data to the MXF Generic Container

  31.  *

  32.  * Principle

  33.  * Search for Track numbers which will identify essence element KLV packets.

  34.  * Search for SourcePackage which define tracks which contains Track numbers.

  35.  * Material Package contains tracks with reference to SourcePackage tracks.

  36.  * Search for Descriptors (Picture, Sound) which contains codec info and parameters.

  37.  * Assign Descriptors to correct Tracks.

  38.  *

  39.  * Metadata reading functions read Local Tags, get InstanceUID(0x3C0A) then add MetaDataSet to MXFContext.

  40.  * Metadata parsing resolves Strong References to objects.

  41.  *

  42.  * Simple demuxer, only OP1A supported and some files might not work at all.

  43.  * Only tracks with associated descriptors will be decoded. "Highly Desirable" SMPTE 377M D.1

  44.  */

  45. 

  46. //#define DEBUG

  47. 

  48. #include "libavutil/aes.h"

  49. #include "libavutil/mathematics.h"

  50. #include "libavcodec/bytestream.h"

  51. #include "avformat.h"

  52. #include "internal.h"

  53. #include "mxf.h"

  54. 

  55. typedef enum {

  56.     Header,

  57.     BodyPartition,

  58.     Footer

  59. } MXFPartitionType;

  60. 

  61. typedef enum {

  62.     OP1a,

  63.     OP1b,

  64.     OP1c,

  65.     OP2a,

  66.     OP2b,

  67.     OP2c,

  68.     OP3a,

  69.     OP3b,

  70.     OP3c,

  71.     OPAtom,

  72.     OPSONYOpt,  /* FATE sample, violates the spec in places */

  73. } MXFOP;

  74. 

  75. typedef struct {

  76.     int closed;

  77.     int complete;

  78.     MXFPartitionType type;

  79.     uint64_t previous_partition;

  80.     int index_sid;

  81.     int body_sid;

  82.     int64_t this_partition;

  83.     int64_t essence_offset;         /* absolute offset of essence */

  84.     int64_t essence_length;

  85.     int32_t kag_size;

  86.     int64_t header_byte_count;

  87.     int64_t index_byte_count;

  88.     int pack_length;

  89. } MXFPartition;

  90. 

  91. typedef struct {

  92.     UID uid;

  93.     enum MXFMetadataSetType type;

  94.     UID source_container_ul;

  95. } MXFCryptoContext;

  96. 

  97. typedef struct {

  98.     UID uid;

  99.     enum MXFMetadataSetType type;

  100.     UID source_package_uid;

  101.     UID data_definition_ul;

  102.     int64_t duration;

  103.     int64_t start_position;

  104.     int source_track_id;

  105. } MXFStructuralComponent;

  106. 

  107. typedef struct {

  108.     UID uid;

  109.     enum MXFMetadataSetType type;

  110.     UID data_definition_ul;

  111.     UID *structural_components_refs;

  112.     int structural_components_count;

  113.     int64_t duration;

  114. } MXFSequence;

  115. 

  116. typedef struct {

  117.     UID uid;

  118.     enum MXFMetadataSetType type;

  119.     MXFSequence *sequence; /* mandatory, and only one */

  120.     UID sequence_ref;

  121.     int track_id;

  122.     uint8_t track_number[4];

  123.     AVRational edit_rate;

  124. } MXFTrack;

  125. 

  126. typedef struct {

  127.     UID uid;

  128.     enum MXFMetadataSetType type;

  129.     UID essence_container_ul;

  130.     UID essence_codec_ul;

  131.     AVRational sample_rate;

  132.     AVRational aspect_ratio;

  133.     int width;

  134.     int height;

  135.     int channels;

  136.     int bits_per_sample;

  137.     UID *sub_descriptors_refs;

  138.     int sub_descriptors_count;

  139.     int linked_track_id;

  140.     uint8_t *extradata;

  141.     int extradata_size;

  142.     enum PixelFormat pix_fmt;

  143. } MXFDescriptor;

  144. 

  145. typedef struct {

  146.     UID uid;

  147.     enum MXFMetadataSetType type;

  148.     int edit_unit_byte_count;

  149.     int index_sid;

  150.     int body_sid;

  151.     AVRational index_edit_rate;

  152.     uint64_t index_start_position;

  153.     uint64_t index_duration;

  154.     int8_t *temporal_offset_entries;

  155.     int *flag_entries;

  156.     uint64_t *stream_offset_entries;

  157.     int nb_index_entries;

  158. } MXFIndexTableSegment;

  159. 

  160. typedef struct {

  161.     UID uid;

  162.     enum MXFMetadataSetType type;

  163.     UID package_uid;

  164.     UID *tracks_refs;

  165.     int tracks_count;

  166.     MXFDescriptor *descriptor; /* only one */

  167.     UID descriptor_ref;

  168. } MXFPackage;

  169. 

  170. typedef struct {

  171.     UID uid;

  172.     enum MXFMetadataSetType type;

  173. } MXFMetadataSet;

  174. 

  175. /* decoded index table */

  176. typedef struct {

  177.     int index_sid;

  178.     int body_sid;

  179.     int nb_ptses;               /* number of PTSes or total duration of index */

  180.     int64_t first_dts;          /* DTS = EditUnit + first_dts */

  181.     int64_t *ptses;             /* maps EditUnit -> PTS */

  182.     int nb_segments;

  183.     MXFIndexTableSegment **segments;    /* sorted by IndexStartPosition */

  184.     AVIndexEntry *fake_index;   /* used for calling ff_index_search_timestamp() */

  185. } MXFIndexTable;

  186. 

  187. typedef struct {

  188.     MXFPartition *partitions;

  189.     unsigned partitions_count;

  190.     MXFOP op;

  191.     UID *packages_refs;

  192.     int packages_count;

  193.     MXFMetadataSet **metadata_sets;

  194.     int metadata_sets_count;

  195.     AVFormatContext *fc;

  196.     struct AVAES *aesc;

  197.     uint8_t *local_tags;

  198.     int local_tags_count;

  199.     uint64_t footer_partition;

  200.     KLVPacket current_klv_data;

  201.     int current_klv_index;

  202.     int run_in;

  203.     MXFPartition *current_partition;

  204.     int parsing_backward;

  205.     int64_t last_forward_tell;

  206.     int last_forward_partition;

  207.     int current_edit_unit;

  208.     int nb_index_tables;

  209.     MXFIndexTable *index_tables;

  210. } MXFContext;

  211. 

  212. enum MXFWrappingScheme {

  213.     Frame,

  214.     Clip,

  215. };

  216. 

  217. /* NOTE: klv_offset is not set (-1) for local keys */

  218. typedef int MXFMetadataReadFunc(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset);

  219. 

  220. typedef struct {

  221.     const UID key;

  222.     MXFMetadataReadFunc *read;

  223.     int ctx_size;

  224.     enum MXFMetadataSetType type;

  225. } MXFMetadataReadTableEntry;

  226. 

  227. /* partial keys to match */

  228. static const uint8_t mxf_header_partition_pack_key[]       = { 0x06,0x0e,0x2b,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x02 };

  229. static const uint8_t mxf_essence_element_key[]             = { 0x06,0x0e,0x2b,0x34,0x01,0x02,0x01,0x01,0x0d,0x01,0x03,0x01 };

  230. static const uint8_t mxf_avid_essence_element_key[]        = { 0x06,0x0e,0x2b,0x34,0x01,0x02,0x01,0x01,0x0e,0x04,0x03,0x01 };

  231. static const uint8_t mxf_system_item_key[]                 = { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0D,0x01,0x03,0x01,0x04 };

  232. static const uint8_t mxf_klv_key[]                         = { 0x06,0x0e,0x2b,0x34 };

  233. /* complete keys to match */

  234. static const uint8_t mxf_crypto_source_container_ul[]      = { 0x06,0x0e,0x2b,0x34,0x01,0x01,0x01,0x09,0x06,0x01,0x01,0x02,0x02,0x00,0x00,0x00 };

  235. static const uint8_t mxf_encrypted_triplet_key[]           = { 0x06,0x0e,0x2b,0x34,0x02,0x04,0x01,0x07,0x0d,0x01,0x03,0x01,0x02,0x7e,0x01,0x00 };

  236. static const uint8_t mxf_encrypted_essence_container[]     = { 0x06,0x0e,0x2b,0x34,0x04,0x01,0x01,0x07,0x0d,0x01,0x03,0x01,0x02,0x0b,0x01,0x00 };

  237. static const uint8_t mxf_sony_mpeg4_extradata[]            = { 0x06,0x0e,0x2b,0x34,0x04,0x01,0x01,0x01,0x0e,0x06,0x06,0x02,0x02,0x01,0x00,0x00 };

  238. 

  239. #define IS_KLV_KEY(x, y) (!memcmp(x, y, sizeof(y)))

  240. 

  241. static int64_t klv_decode_ber_length(AVIOContext *pb)

  242. {

  243.     uint64_t size = avio_r8(pb);

  244.     if (size & 0x80) { /* long form */

  245.         int bytes_num = size & 0x7f;

  246.         /* SMPTE 379M 5.3.4 guarantee that bytes_num must not exceed 8 bytes */

  247.         if (bytes_num > 8)

  248.             return -1;

  249.         size = 0;

  250.         while (bytes_num--)

  251.             size = size << 8 | avio_r8(pb);

  252.     }

  253.     return size;

  254. }

  255. 

  256. static int mxf_read_sync(AVIOContext *pb, const uint8_t *key, unsigned size)

  257. {

  258.     int i, b;

  259.     for (i = 0; i < size && !url_feof(pb); i++) {

  260.         b = avio_r8(pb);

  261.         if (b == key[0])

  262.             i = 0;

  263.         else if (b != key[i])

  264.             i = -1;

  265.     }

  266.     return i == size;

  267. }

  268. 

  269. static int klv_read_packet(KLVPacket *klv, AVIOContext *pb)

  270. {

  271.     if (!mxf_read_sync(pb, mxf_klv_key, 4))

  272.         return -1;

  273.     klv->offset = avio_tell(pb) - 4;

  274.     memcpy(klv->key, mxf_klv_key, 4);

  275.     avio_read(pb, klv->key + 4, 12);

  276.     klv->length = klv_decode_ber_length(pb);

  277.     return klv->length == -1 ? -1 : 0;

  278. }

  279. 

  280. static int mxf_get_stream_index(AVFormatContext *s, KLVPacket *klv)

  281. {

  282.     int i;

  283. 

  284.     for (i = 0; i < s->nb_streams; i++) {

  285.         MXFTrack *track = s->streams[i]->priv_data;

  286.         /* SMPTE 379M 7.3 */

  287.         if (!memcmp(klv->key + sizeof(mxf_essence_element_key), track->track_number, sizeof(track->track_number)))

  288.             return i;

  289.     }

  290.     /* return 0 if only one stream, for OP Atom files with 0 as track number */

  291.     return s->nb_streams == 1 ? 0 : -1;

  292. }

  293. 

  294. /* XXX: use AVBitStreamFilter */

  295. static int mxf_get_d10_aes3_packet(AVIOContext *pb, AVStream *st, AVPacket *pkt, int64_t length)

  296. {

  297.     const uint8_t *buf_ptr, *end_ptr;

  298.     uint8_t *data_ptr;

  299.     int i;

  300. 

  301.     if (length > 61444) /* worst case PAL 1920 samples 8 channels */

  302.         return -1;

  303.     length = av_get_packet(pb, pkt, length);

  304.     if (length < 0)

  305.         return length;

  306.     data_ptr = pkt->data;

  307.     end_ptr = pkt->data + length;

  308.     buf_ptr = pkt->data + 4; /* skip SMPTE 331M header */

  309.     for (; buf_ptr + st->codec->channels*4 < end_ptr; ) {

  310.         for (i = 0; i < st->codec->channels; i++) {

  311.             uint32_t sample = bytestream_get_le32(&buf_ptr);

  312.             if (st->codec->bits_per_coded_sample == 24)

  313.                 bytestream_put_le24(&data_ptr, (sample >> 4) & 0xffffff);

  314.             else

  315.                 bytestream_put_le16(&data_ptr, (sample >> 12) & 0xffff);

  316.         }

  317.         buf_ptr += 32 - st->codec->channels*4; // always 8 channels stored SMPTE 331M

  318.     }

  319.     av_shrink_packet(pkt, data_ptr - pkt->data);

  320.     return 0;

  321. }

  322. 

  323. static int mxf_decrypt_triplet(AVFormatContext *s, AVPacket *pkt, KLVPacket *klv)

  324. {

  325.     static const uint8_t checkv[16] = {0x43, 0x48, 0x55, 0x4b, 0x43, 0x48, 0x55, 0x4b, 0x43, 0x48, 0x55, 0x4b, 0x43, 0x48, 0x55, 0x4b};

  326.     MXFContext *mxf = s->priv_data;

  327.     AVIOContext *pb = s->pb;

  328.     int64_t end = avio_tell(pb) + klv->length;

  329.     int64_t size;

  330.     uint64_t orig_size;

  331.     uint64_t plaintext_size;

  332.     uint8_t ivec[16];

  333.     uint8_t tmpbuf[16];

  334.     int index;

  335. 

  336.     if (!mxf->aesc && s->key && s->keylen == 16) {

  337.         mxf->aesc = av_malloc(av_aes_size);

  338.         if (!mxf->aesc)

  339.             return -1;

  340.         av_aes_init(mxf->aesc, s->key, 128, 1);

  341.     }

  342.     // crypto context

  343.     avio_skip(pb, klv_decode_ber_length(pb));

  344.     // plaintext offset

  345.     klv_decode_ber_length(pb);

  346.     plaintext_size = avio_rb64(pb);

  347.     // source klv key

  348.     klv_decode_ber_length(pb);

  349.     avio_read(pb, klv->key, 16);

  350.     if (!IS_KLV_KEY(klv, mxf_essence_element_key))

  351.         return -1;

  352.     index = mxf_get_stream_index(s, klv);

  353.     if (index < 0)

  354.         return -1;

  355.     // source size

  356.     klv_decode_ber_length(pb);

  357.     orig_size = avio_rb64(pb);

  358.     if (orig_size < plaintext_size)

  359.         return -1;

  360.     // enc. code

  361.     size = klv_decode_ber_length(pb);

  362.     if (size < 32 || size - 32 < orig_size)

  363.         return -1;

  364.     avio_read(pb, ivec, 16);

  365.     avio_read(pb, tmpbuf, 16);

  366.     if (mxf->aesc)

  367.         av_aes_crypt(mxf->aesc, tmpbuf, tmpbuf, 1, ivec, 1);

  368.     if (memcmp(tmpbuf, checkv, 16))

  369.         av_log(s, AV_LOG_ERROR, "probably incorrect decryption key\n");

  370.     size -= 32;

  371.     size = av_get_packet(pb, pkt, size);

  372.     if (size < 0)

  373.         return size;

  374.     else if (size < plaintext_size)

  375.         return AVERROR_INVALIDDATA;

  376.     size -= plaintext_size;

  377.     if (mxf->aesc)

  378.         av_aes_crypt(mxf->aesc, &pkt->data[plaintext_size],

  379.                      &pkt->data[plaintext_size], size >> 4, ivec, 1);

  380.     av_shrink_packet(pkt, orig_size);

  381.     pkt->stream_index = index;

  382.     avio_skip(pb, end - avio_tell(pb));

  383.     return 0;

  384. }

  385. 

  386. static int mxf_read_primer_pack(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  387. {

  388.     MXFContext *mxf = arg;

  389.     int item_num = avio_rb32(pb);

  390.     int item_len = avio_rb32(pb);

  391. 

  392.     if (item_len != 18) {

  393.         av_log(mxf->fc, AV_LOG_ERROR, "unsupported primer pack item length\n");

  394.         return -1;

  395.     }

  396.     if (item_num > UINT_MAX / item_len)

  397.         return -1;

  398.     mxf->local_tags_count = item_num;

  399.     mxf->local_tags = av_malloc(item_num*item_len);

  400.     if (!mxf->local_tags)

  401.         return -1;

  402.     avio_read(pb, mxf->local_tags, item_num*item_len);

  403.     return 0;

  404. }

  405. 

  406. static int mxf_read_partition_pack(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  407. {

  408.     MXFContext *mxf = arg;

  409.     MXFPartition *partition;

  410.     UID op;

  411.     uint64_t footer_partition;

  412. 

  413.     if (mxf->partitions_count+1 >= UINT_MAX / sizeof(*mxf->partitions))

  414.         return AVERROR(ENOMEM);

  415. 

  416.     mxf->partitions = av_realloc(mxf->partitions, (mxf->partitions_count + 1) * sizeof(*mxf->partitions));

  417.     if (!mxf->partitions)

  418.         return AVERROR(ENOMEM);

  419. 

  420.     if (mxf->parsing_backward) {

  421.         /* insert the new partition pack in the middle

  422.          * this makes the entries in mxf->partitions sorted by offset */

  423.         memmove(&mxf->partitions[mxf->last_forward_partition+1],

  424.                 &mxf->partitions[mxf->last_forward_partition],

  425.                 (mxf->partitions_count - mxf->last_forward_partition)*sizeof(*mxf->partitions));

  426.         partition = mxf->current_partition = &mxf->partitions[mxf->last_forward_partition];

  427.     } else {

  428.         mxf->last_forward_partition++;

  429.         partition = mxf->current_partition = &mxf->partitions[mxf->partitions_count];

  430.     }

  431. 

  432.     memset(partition, 0, sizeof(*partition));

  433.     mxf->partitions_count++;

  434.     partition->pack_length = avio_tell(pb) - klv_offset + size;

  435. 

  436.     switch(uid[13]) {

  437.     case 2:

  438.         partition->type = Header;

  439.         break;

  440.     case 3:

  441.         partition->type = BodyPartition;

  442.         break;

  443.     case 4:

  444.         partition->type = Footer;

  445.         break;

  446.     default:

  447.         av_log(mxf->fc, AV_LOG_ERROR, "unknown partition type %i\n", uid[13]);

  448.         return AVERROR_INVALIDDATA;

  449.     }

  450. 

  451.     /* consider both footers to be closed (there is only Footer and CompleteFooter) */

  452.     partition->closed = partition->type == Footer || !(uid[14] & 1);

  453.     partition->complete = uid[14] > 2;

  454.     avio_skip(pb, 4);

  455.     partition->kag_size = avio_rb32(pb);

  456.     partition->this_partition = avio_rb64(pb);

  457.     partition->previous_partition = avio_rb64(pb);

  458.     footer_partition = avio_rb64(pb);

  459.     partition->header_byte_count = avio_rb64(pb);

  460.     partition->index_byte_count = avio_rb64(pb);

  461.     partition->index_sid = avio_rb32(pb);

  462.     avio_skip(pb, 8);

  463.     partition->body_sid = avio_rb32(pb);

  464.     avio_read(pb, op, sizeof(UID));

  465. 

  466.     /* some files don'thave FooterPartition set in every partition */

  467.     if (footer_partition) {

  468.         if (mxf->footer_partition && mxf->footer_partition != footer_partition) {

  469.             av_log(mxf->fc, AV_LOG_ERROR, "inconsistent FooterPartition value: %li != %li\n",

  470.                    mxf->footer_partition, footer_partition);

  471.         } else {

  472.             mxf->footer_partition = footer_partition;

  473.         }

  474.     }

  475. 

  476.     av_dlog(mxf->fc, "PartitionPack: ThisPartition = 0x%lx, PreviousPartition = 0x%lx, "

  477.             "FooterPartition = 0x%lx, IndexSID = %i, BodySID = %i\n",

  478.             partition->this_partition,

  479.             partition->previous_partition, footer_partition,

  480.             partition->index_sid, partition->body_sid);

  481. 

  482.     if      (op[12] == 1 && op[13] == 1) mxf->op = OP1a;

  483.     else if (op[12] == 1 && op[13] == 2) mxf->op = OP1b;

  484.     else if (op[12] == 1 && op[13] == 3) mxf->op = OP1c;

  485.     else if (op[12] == 2 && op[13] == 1) mxf->op = OP2a;

  486.     else if (op[12] == 2 && op[13] == 2) mxf->op = OP2b;

  487.     else if (op[12] == 2 && op[13] == 3) mxf->op = OP2c;

  488.     else if (op[12] == 3 && op[13] == 1) mxf->op = OP3a;

  489.     else if (op[12] == 3 && op[13] == 2) mxf->op = OP3b;

  490.     else if (op[12] == 3 && op[13] == 3) mxf->op = OP3c;

  491.     else if (op[12] == 0x10)             mxf->op = OPAtom;

  492.     else if (op[12] == 64&& op[13] == 1) mxf->op = OPSONYOpt;

  493.     else {

  494.         av_log(mxf->fc, AV_LOG_ERROR, "unknown operational pattern: %02xh %02xh - guessing OP1a\n", op[12], op[13]);

  495.         mxf->op = OP1a;

  496.     }

  497. 

  498.     if (partition->kag_size <= 0 || partition->kag_size > (1 << 20)) {

  499.         av_log(mxf->fc, AV_LOG_WARNING, "invalid KAGSize %i - guessing ", partition->kag_size);

  500. 

  501.         if (mxf->op == OPSONYOpt)

  502.             partition->kag_size = 512;

  503.         else

  504.             partition->kag_size = 1;

  505. 

  506.         av_log(mxf->fc, AV_LOG_WARNING, "%i\n", partition->kag_size);

  507.     }

  508. 

  509.     return 0;

  510. }

  511. 

  512. static int mxf_add_metadata_set(MXFContext *mxf, void *metadata_set)

  513. {

  514.     if (mxf->metadata_sets_count+1 >= UINT_MAX / sizeof(*mxf->metadata_sets))

  515.         return AVERROR(ENOMEM);

  516.     mxf->metadata_sets = av_realloc(mxf->metadata_sets, (mxf->metadata_sets_count + 1) * sizeof(*mxf->metadata_sets));

  517.     if (!mxf->metadata_sets)

  518.         return -1;

  519.     mxf->metadata_sets[mxf->metadata_sets_count] = metadata_set;

  520.     mxf->metadata_sets_count++;

  521.     return 0;

  522. }

  523. 

  524. static int mxf_read_cryptographic_context(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  525. {

  526.     MXFCryptoContext *cryptocontext = arg;

  527.     if (size != 16)

  528.         return -1;

  529.     if (IS_KLV_KEY(uid, mxf_crypto_source_container_ul))

  530.         avio_read(pb, cryptocontext->source_container_ul, 16);

  531.     return 0;

  532. }

  533. 

  534. static int mxf_read_content_storage(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  535. {

  536.     MXFContext *mxf = arg;

  537.     switch (tag) {

  538.     case 0x1901:

  539.         mxf->packages_count = avio_rb32(pb);

  540.         if (mxf->packages_count >= UINT_MAX / sizeof(UID))

  541.             return -1;

  542.         mxf->packages_refs = av_malloc(mxf->packages_count * sizeof(UID));

  543.         if (!mxf->packages_refs)

  544.             return -1;

  545.         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */

  546.         avio_read(pb, (uint8_t *)mxf->packages_refs, mxf->packages_count * sizeof(UID));

  547.         break;

  548.     }

  549.     return 0;

  550. }

  551. 

  552. static int mxf_read_source_clip(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  553. {

  554.     MXFStructuralComponent *source_clip = arg;

  555.     switch(tag) {

  556.     case 0x0202:

  557.         source_clip->duration = avio_rb64(pb);

  558.         break;

  559.     case 0x1201:

  560.         source_clip->start_position = avio_rb64(pb);

  561.         break;

  562.     case 0x1101:

  563.         /* UMID, only get last 16 bytes */

  564.         avio_skip(pb, 16);

  565.         avio_read(pb, source_clip->source_package_uid, 16);

  566.         break;

  567.     case 0x1102:

  568.         source_clip->source_track_id = avio_rb32(pb);

  569.         break;

  570.     }

  571.     return 0;

  572. }

  573. 

  574. static int mxf_read_material_package(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  575. {

  576.     MXFPackage *package = arg;

  577.     switch(tag) {

  578.     case 0x4403:

  579.         package->tracks_count = avio_rb32(pb);

  580.         if (package->tracks_count >= UINT_MAX / sizeof(UID))

  581.             return -1;

  582.         package->tracks_refs = av_malloc(package->tracks_count * sizeof(UID));

  583.         if (!package->tracks_refs)

  584.             return -1;

  585.         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */

  586.         avio_read(pb, (uint8_t *)package->tracks_refs, package->tracks_count * sizeof(UID));

  587.         break;

  588.     }

  589.     return 0;

  590. }

  591. 

  592. static int mxf_read_track(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  593. {

  594.     MXFTrack *track = arg;

  595.     switch(tag) {

  596.     case 0x4801:

  597.         track->track_id = avio_rb32(pb);

  598.         break;

  599.     case 0x4804:

  600.         avio_read(pb, track->track_number, 4);

  601.         break;

  602.     case 0x4B01:

  603.         track->edit_rate.den = avio_rb32(pb);

  604.         track->edit_rate.num = avio_rb32(pb);

  605.         break;

  606.     case 0x4803:

  607.         avio_read(pb, track->sequence_ref, 16);

  608.         break;

  609.     }

  610.     return 0;

  611. }

  612. 

  613. static int mxf_read_sequence(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  614. {

  615.     MXFSequence *sequence = arg;

  616.     switch(tag) {

  617.     case 0x0202:

  618.         sequence->duration = avio_rb64(pb);

  619.         break;

  620.     case 0x0201:

  621.         avio_read(pb, sequence->data_definition_ul, 16);

  622.         break;

  623.     case 0x1001:

  624.         sequence->structural_components_count = avio_rb32(pb);

  625.         if (sequence->structural_components_count >= UINT_MAX / sizeof(UID))

  626.             return -1;

  627.         sequence->structural_components_refs = av_malloc(sequence->structural_components_count * sizeof(UID));

  628.         if (!sequence->structural_components_refs)

  629.             return -1;

  630.         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */

  631.         avio_read(pb, (uint8_t *)sequence->structural_components_refs, sequence->structural_components_count * sizeof(UID));

  632.         break;

  633.     }

  634.     return 0;

  635. }

  636. 

  637. static int mxf_read_source_package(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  638. {

  639.     MXFPackage *package = arg;

  640.     switch(tag) {

  641.     case 0x4403:

  642.         package->tracks_count = avio_rb32(pb);

  643.         if (package->tracks_count >= UINT_MAX / sizeof(UID))

  644.             return -1;

  645.         package->tracks_refs = av_malloc(package->tracks_count * sizeof(UID));

  646.         if (!package->tracks_refs)

  647.             return -1;

  648.         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */

  649.         avio_read(pb, (uint8_t *)package->tracks_refs, package->tracks_count * sizeof(UID));

  650.         break;

  651.     case 0x4401:

  652.         /* UMID, only get last 16 bytes */

  653.         avio_skip(pb, 16);

  654.         avio_read(pb, package->package_uid, 16);

  655.         break;

  656.     case 0x4701:

  657.         avio_read(pb, package->descriptor_ref, 16);

  658.         break;

  659.     }

  660.     return 0;

  661. }

  662. 

  663. static int mxf_read_index_entry_array(AVIOContext *pb, MXFIndexTableSegment *segment)

  664. {

  665.     int i, j, length;

  666. 

  667.     segment->nb_index_entries = avio_rb32(pb);

  668.     length = avio_rb32(pb);

  669. 

  670.     if (!(segment->temporal_offset_entries=av_calloc(segment->nb_index_entries, sizeof(*segment->temporal_offset_entries))) ||

  671.         !(segment->flag_entries          = av_calloc(segment->nb_index_entries, sizeof(*segment->flag_entries))) ||

  672.         !(segment->stream_offset_entries = av_calloc(segment->nb_index_entries, sizeof(*segment->stream_offset_entries))))

  673.         return AVERROR(ENOMEM);

  674. 

  675.     for (i = 0; i < segment->nb_index_entries; i++) {

  676.         segment->temporal_offset_entries[i] = avio_r8(pb);

  677.         avio_r8(pb);                                        /* KeyFrameOffset */

  678.         segment->flag_entries[i] = avio_r8(pb);

  679.         segment->stream_offset_entries[i] = avio_rb64(pb);

  680.         avio_skip(pb, length - 11);

  681.     }

  682.     return 0;

  683. }

  684. 

  685. static int mxf_read_index_table_segment(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  686. {

  687.     MXFIndexTableSegment *segment = arg;

  688.     switch(tag) {

  689.     case 0x3F05:

  690.         segment->edit_unit_byte_count = avio_rb32(pb);

  691.         av_dlog(NULL, "EditUnitByteCount %d\n", segment->edit_unit_byte_count);

  692.         break;

  693.     case 0x3F06:

  694.         segment->index_sid = avio_rb32(pb);

  695.         av_dlog(NULL, "IndexSID %d\n", segment->index_sid);

  696.         break;

  697.     case 0x3F07:

  698.         segment->body_sid = avio_rb32(pb);

  699.         av_dlog(NULL, "BodySID %d\n", segment->body_sid);

  700.         break;

  701.     case 0x3F0A:

  702.         av_dlog(NULL, "IndexEntryArray found\n");

  703.         return mxf_read_index_entry_array(pb, segment);

  704.     case 0x3F0B:

  705.         segment->index_edit_rate.num = avio_rb32(pb);

  706.         segment->index_edit_rate.den = avio_rb32(pb);

  707.         av_dlog(NULL, "IndexEditRate %d/%d\n", segment->index_edit_rate.num,

  708.                 segment->index_edit_rate.den);

  709.         break;

  710.     case 0x3F0C:

  711.         segment->index_start_position = avio_rb64(pb);

  712.         av_dlog(NULL, "IndexStartPosition %"PRId64"\n", segment->index_start_position);

  713.         break;

  714.     case 0x3F0D:

  715.         segment->index_duration = avio_rb64(pb);

  716.         av_dlog(NULL, "IndexDuration %"PRId64"\n", segment->index_duration);

  717.         break;

  718.     }

  719.     return 0;

  720. }

  721. 

  722. static void mxf_read_pixel_layout(AVIOContext *pb, MXFDescriptor *descriptor)

  723. {

  724.     int code, value, ofs = 0;

  725.     char layout[16] = {0};

  726. 

  727.     do {

  728.         code = avio_r8(pb);

  729.         value = avio_r8(pb);

  730.         av_dlog(NULL, "pixel layout: code %#x\n", code);

  731. 

  732.         if (ofs < 16) {

  733.             layout[ofs++] = code;

  734.             layout[ofs++] = value;

  735.         }

  736.     } while (code != 0); /* SMPTE 377M E.2.46 */

  737. 

  738.     ff_mxf_decode_pixel_layout(layout, &descriptor->pix_fmt);

  739. }

  740. 

  741. static int mxf_read_generic_descriptor(void *arg, AVIOContext *pb, int tag, int size, UID uid, int64_t klv_offset)

  742. {

  743.     MXFDescriptor *descriptor = arg;

  744.     switch(tag) {

  745.     case 0x3F01:

  746.         descriptor->sub_descriptors_count = avio_rb32(pb);

  747.         if (descriptor->sub_descriptors_count >= UINT_MAX / sizeof(UID))

  748.             return -1;

  749.         descriptor->sub_descriptors_refs = av_malloc(descriptor->sub_descriptors_count * sizeof(UID));

  750.         if (!descriptor->sub_descriptors_refs)

  751.             return -1;

  752.         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */

  753.         avio_read(pb, (uint8_t *)descriptor->sub_descriptors_refs, descriptor->sub_descriptors_count * sizeof(UID));

  754.         break;

  755.     case 0x3004:

  756.         avio_read(pb, descriptor->essence_container_ul, 16);

  757.         break;

  758.     case 0x3006:

  759.         descriptor->linked_track_id = avio_rb32(pb);

  760.         break;

  761.     case 0x3201: /* PictureEssenceCoding */

  762.         avio_read(pb, descriptor->essence_codec_ul, 16);

  763.         break;

  764.     case 0x3203:

  765.         descriptor->width = avio_rb32(pb);

  766.         break;

  767.     case 0x3202:

  768.         descriptor->height = avio_rb32(pb);

  769.         break;

  770.     case 0x320E:

  771.         descriptor->aspect_ratio.num = avio_rb32(pb);

  772.         descriptor->aspect_ratio.den = avio_rb32(pb);

  773.         break;

  774.     case 0x3D03:

  775.         descriptor->sample_rate.num = avio_rb32(pb);

  776.         descriptor->sample_rate.den = avio_rb32(pb);

  777.         break;

  778.     case 0x3D06: /* SoundEssenceCompression */

  779.         avio_read(pb, descriptor->essence_codec_ul, 16);

  780.         break;

  781.     case 0x3D07:

  782.         descriptor->channels = avio_rb32(pb);

  783.         break;

  784.     case 0x3D01:

  785.         descriptor->bits_per_sample = avio_rb32(pb);

  786.         break;

  787.     case 0x3401:

  788.         mxf_read_pixel_layout(pb, descriptor);

  789.         break;

  790.     default:

  791.         /* Private uid used by SONY C0023S01.mxf */

  792.         if (IS_KLV_KEY(uid, mxf_sony_mpeg4_extradata)) {

  793.             descriptor->extradata = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);

  794.             if (!descriptor->extradata)

  795.                 return -1;

  796.             descriptor->extradata_size = size;

  797.             avio_read(pb, descriptor->extradata, size);

  798.         }

  799.         break;

  800.     }

  801.     return 0;

  802. }

  803. 

  804. /*

  805.  * Match an uid independently of the version byte and up to len common bytes

  806.  * Returns: boolean

  807.  */

  808. static int mxf_match_uid(const UID key, const UID uid, int len)

  809. {

  810.     int i;

  811.     for (i = 0; i < len; i++) {

  812.         if (i != 7 && key[i] != uid[i])

  813.             return 0;

  814.     }

  815.     return 1;

  816. }

  817. 

  818. static const MXFCodecUL *mxf_get_codec_ul(const MXFCodecUL *uls, UID *uid)

  819. {

  820.     while (uls->uid[0]) {

  821.         if(mxf_match_uid(uls->uid, *uid, uls->matching_len))

  822.             break;

  823.         uls++;

  824.     }

  825.     return uls;

  826. }

  827. 

  828. static void *mxf_resolve_strong_ref(MXFContext *mxf, UID *strong_ref, enum MXFMetadataSetType type)

  829. {

  830.     int i;

  831. 

  832.     if (!strong_ref)

  833.         return NULL;

  834.     for (i = 0; i < mxf->metadata_sets_count; i++) {

  835.         if (!memcmp(*strong_ref, mxf->metadata_sets[i]->uid, 16) &&

  836.             (type == AnyType || mxf->metadata_sets[i]->type == type)) {

  837.             return mxf->metadata_sets[i];

  838.         }

  839.     }

  840.     return NULL;

  841. }

  842. 

  843. static const MXFCodecUL mxf_picture_essence_container_uls[] = {

  844.     // video essence container uls

  845.     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x02,0x0D,0x01,0x03,0x01,0x02,0x04,0x60,0x01 }, 14, CODEC_ID_MPEG2VIDEO }, /* MPEG-ES Frame wrapped */

  846.     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x0D,0x01,0x03,0x01,0x02,0x02,0x41,0x01 }, 14,    CODEC_ID_DVVIDEO }, /* DV 625 25mbps */

  847.     { { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },  0,      CODEC_ID_NONE },

  848. };

  849. static const MXFCodecUL mxf_sound_essence_container_uls[] = {

  850.     // sound essence container uls

  851.     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x0D,0x01,0x03,0x01,0x02,0x06,0x01,0x00 }, 14, CODEC_ID_PCM_S16LE }, /* BWF Frame wrapped */

  852.     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x02,0x0D,0x01,0x03,0x01,0x02,0x04,0x40,0x01 }, 14,       CODEC_ID_MP2 }, /* MPEG-ES Frame wrapped, 0x40 ??? stream id */

  853.     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x0D,0x01,0x03,0x01,0x02,0x01,0x01,0x01 }, 14, CODEC_ID_PCM_S16LE }, /* D-10 Mapping 50Mbps PAL Extended Template */

  854.     { { 0x06,0x0E,0x2B,0x34,0x01,0x01,0x01,0xFF,0x4B,0x46,0x41,0x41,0x00,0x0D,0x4D,0x4F }, 14, CODEC_ID_PCM_S16LE }, /* 0001GL00.MXF.A1.mxf_opatom.mxf */

  855.     { { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },  0,      CODEC_ID_NONE },

  856. };

  857. 

  858. static int mxf_get_sorted_table_segments(MXFContext *mxf, int *nb_sorted_segments, MXFIndexTableSegment ***sorted_segments)

  859. {

  860.     int i, j, nb_segments = 0;

  861.     MXFIndexTableSegment **unsorted_segments;

  862.     int last_body_sid = -1, last_index_sid = -1, last_index_start = -1;

  863. 

  864.     /* count number of segments, allocate arrays and copy unsorted segments */

  865.     for (i = 0; i < mxf->metadata_sets_count; i++)

  866.         if (mxf->metadata_sets[i]->type == IndexTableSegment)

  867.             nb_segments++;

  868. 

  869.     if (!(unsorted_segments = av_calloc(nb_segments, sizeof(*unsorted_segments))) ||

  870.         !(*sorted_segments  = av_calloc(nb_segments, sizeof(**sorted_segments)))) {

  871.         av_free(unsorted_segments);

  872.         return AVERROR(ENOMEM);

  873.     }

  874. 

  875.     for (i = j = 0; i < mxf->metadata_sets_count; i++)

  876.         if (mxf->metadata_sets[i]->type == IndexTableSegment)

  877.             unsorted_segments[j++] = (MXFIndexTableSegment*)mxf->metadata_sets[i];

  878. 

  879.     *nb_sorted_segments = 0;

  880. 

  881.     /* sort segments by {BodySID, IndexSID, IndexStartPosition}, remove duplicates while we're at it */

  882.     for (i = 0; i < nb_segments; i++) {

  883.         int best = -1, best_body_sid = -1, best_index_sid = -1, best_index_start = -1;

  884. 

  885.         for (j = 0; j < nb_segments; j++) {

  886.             MXFIndexTableSegment *s = unsorted_segments[j];

  887. 

  888.             /* Require larger BosySID, IndexSID or IndexStartPosition then the previous entry. This removes duplicates.

  889.              * We want the smallest values for the keys than what we currently have, unless this is the first such entry this time around.

  890.              */

  891.             if ((i == 0     || s->body_sid > last_body_sid || s->index_sid > last_index_sid || s->index_start_position > last_index_start) &&

  892.                 (best == -1 || s->body_sid < best_body_sid || s->index_sid < best_index_sid || s->index_start_position < best_index_start)) {

  893.                 best             = j;

  894.                 best_body_sid    = s->body_sid;

  895.                 best_index_sid   = s->index_sid;

  896.                 best_index_start = s->index_start_position;

  897.             }

  898.         }

  899. 

  900.         /* no suitable entry found -> we're done */

  901.         if (best == -1)

  902.             break;

  903. 

  904.         (*sorted_segments)[(*nb_sorted_segments)++] = unsorted_segments[best];

  905.         last_body_sid    = best_body_sid;

  906.         last_index_sid   = best_index_sid;

  907.         last_index_start = best_index_start;

  908.     }

  909. 

  910.     av_free(unsorted_segments);

  911. 

  912.     return 0;

  913. }

  914. 

  915. /**

  916.  * Computes the absolute file offset of the given essence container offset

  917.  */

  918. static int mxf_absolute_bodysid_offset(MXFContext *mxf, int body_sid, int64_t offset, int64_t *offset_out)

  919. {

  920.     int x;

  921.     int64_t offset_in = offset;     /* for logging */

  922. 

  923.     for (x = 0; x < mxf->partitions_count; x++) {

  924.         MXFPartition *p = &mxf->partitions[x];

  925. 

  926.         if (p->body_sid != body_sid)

  927.             continue;

  928. 

  929.         if (offset < p->essence_length || !p->essence_length) {

  930.             *offset_out = p->essence_offset + offset;

  931.             return 0;

  932.         }

  933. 

  934.         offset -= p->essence_length;

  935.     }

  936. 

  937.     av_log(mxf->fc, AV_LOG_ERROR, "failed to find absolute offset of %lx in BodySID %i - partial file?\n",

  938.            offset_in, body_sid);

  939. 

  940.     return AVERROR_INVALIDDATA;

  941. }

  942. 

  943. /**

  944.  * Returns the end position of the essence container with given BodySID, or zero if unknown

  945.  */

  946. static int64_t mxf_essence_container_end(MXFContext *mxf, int body_sid)

  947. {

  948.     int x;

  949.     int64_t ret = 0;

  950. 

  951.     for (x = 0; x < mxf->partitions_count; x++) {

  952.         MXFPartition *p = &mxf->partitions[x];

  953. 

  954.         if (p->body_sid != body_sid)

  955.             continue;

  956. 

  957.         if (!p->essence_length)

  958.             return 0;

  959. 

  960.         ret = p->essence_offset + p->essence_length;

  961.     }

  962. 

  963.     return ret;

  964. }

  965. 

  966. /* EditUnit -> absolute offset */

  967. static int mxf_edit_unit_absolute_offset(MXFContext *mxf, MXFIndexTable *index_table, int64_t edit_unit, int64_t *edit_unit_out, int64_t *offset_out, int nag)

  968. {

  969.     int i;

  970.     int offset_temp = 0;

  971. 

  972.     for (i = 0; i < index_table->nb_segments; i++) {

  973.         MXFIndexTableSegment *s = index_table->segments[i];

  974. 

  975.         edit_unit = FFMAX(edit_unit, s->index_start_position);  /* clamp if trying to seek before start */

  976. 

  977.         if (edit_unit < s->index_start_position + s->index_duration) {

  978.             int64_t index = edit_unit - s->index_start_position;

  979. 

  980.             if (s->edit_unit_byte_count)

  981.                 offset_temp += s->edit_unit_byte_count * index;

  982.             else if (s->nb_index_entries) {

  983.                 if (s->nb_index_entries == 2 * s->index_duration + 1)

  984.                     index *= 2;     /* Avid index */

  985. 

  986.                 if (index < 0 || index > s->nb_index_entries) {

  987.                     av_log(mxf->fc, AV_LOG_ERROR, "IndexSID %i segment at %"PRId64" IndexEntryArray too small\n",

  988.                            index_table->index_sid, s->index_start_position);

  989.                     return AVERROR_INVALIDDATA;

  990.                 }

  991. 

  992.                 offset_temp = s->stream_offset_entries[index];

  993.             } else {

  994.                 av_log(mxf->fc, AV_LOG_ERROR, "IndexSID %i segment at %"PRId64" missing EditUnitByteCount and IndexEntryArray\n",

  995.                        index_table->index_sid, s->index_start_position);

  996.                 return AVERROR_INVALIDDATA;

  997.             }

  998. 

  999.             if (edit_unit_out)

  1000.                 *edit_unit_out = edit_unit;

  1001. 

  1002.             return mxf_absolute_bodysid_offset(mxf, index_table->body_sid, offset_temp, offset_out);

  1003.         } else {

  1004.             /* EditUnitByteCount == 0 for VBR indexes, which is fine since they use explicit StreamOffsets */

  1005.             offset_temp += s->edit_unit_byte_count * s->index_duration;

  1006.         }

  1007.     }

  1008. 

  1009.     if (nag)

  1010.         av_log(mxf->fc, AV_LOG_ERROR, "failed to map EditUnit %"PRId64" in IndexSID %i to an offset\n", edit_unit, index_table->index_sid);

  1011. 

  1012.     return AVERROR_INVALIDDATA;

  1013. }

  1014. 

  1015. static int mxf_compute_ptses_fake_index(MXFContext *mxf, MXFIndexTable *index_table)

  1016. {

  1017.     int i, j, x;

  1018.     int8_t max_temporal_offset = -128;

  1019. 

  1020.     /* first compute how many entries we have */

  1021.     for (i = 0; i < index_table->nb_segments; i++) {

  1022.         MXFIndexTableSegment *s = index_table->segments[i];

  1023. 

  1024.         if (!s->nb_index_entries)

  1025.             return 0;                               /* no TemporalOffsets */

  1026. 

  1027.         index_table->nb_ptses += s->index_duration;

  1028.     }

  1029. 

  1030.     /* paranoid check */

  1031.     if (index_table->nb_ptses <= 0)

  1032.         return 0;

  1033. 

  1034.     if (!(index_table->ptses      = av_calloc(index_table->nb_ptses, sizeof(int64_t))) ||

  1035.         !(index_table->fake_index = av_calloc(index_table->nb_ptses, sizeof(AVIndexEntry)))) {

  1036.         av_freep(&index_table->ptses);

  1037.         return AVERROR(ENOMEM);

  1038.     }

  1039. 

  1040.     /* we may have a few bad TemporalOffsets

  1041.      * make sure the corresponding PTSes don't have the bogus value 0 */

  1042.     for (x = 0; x < index_table->nb_ptses; x++)

  1043.         index_table->ptses[x] = AV_NOPTS_VALUE;

  1044. 

  1045.     /**

  1046.      * We have this:

  1047.      *

  1048.      * x  TemporalOffset

  1049.      * 0:  0

  1050.      * 1:  1

  1051.      * 2:  1

  1052.      * 3: -2

  1053.      * 4:  1

  1054.      * 5:  1

  1055.      * 6: -2

  1056.      *

  1057.      * We want to transform it into this:

  1058.      *

  1059.      * x  DTS PTS

  1060.      * 0: -1   0

  1061.      * 1:  0   3

  1062.      * 2:  1   1

  1063.      * 3:  2   2

  1064.      * 4:  3   6

  1065.      * 5:  4   4

  1066.      * 6:  5   5

  1067.      *

  1068.      * We do this by bucket sorting x by x+TemporalOffset[x] into mxf->ptses,

  1069.      * then settings mxf->first_dts = -max(TemporalOffset[x]).

  1070.      * The latter makes DTS <= PTS.

  1071.      */

  1072.     for (i = x = 0; i < index_table->nb_segments; i++) {

  1073.         MXFIndexTableSegment *s = index_table->segments[i];

  1074.         int index_delta = 1;

  1075. 

  1076.         if (s->nb_index_entries == 2 * s->index_duration + 1)

  1077.             index_delta = 2;    /* Avid index */

  1078. 

  1079.         for (j = 0; j < s->nb_index_entries; j += index_delta, x++) {

  1080.             int offset = s->temporal_offset_entries[j] / index_delta;

  1081.             int index  = x + offset;

  1082. 

  1083.             index_table->fake_index[x].timestamp = x;

  1084.             index_table->fake_index[x].flags = !(s->flag_entries[j] & 0x30) ? AVINDEX_KEYFRAME : 0;

  1085. 

  1086.             if (index < 0 || index >= index_table->nb_ptses) {

  1087.                 av_log(mxf->fc, AV_LOG_ERROR,

  1088.                        "index entry %i + TemporalOffset %i = %i, which is out of bounds\n",

  1089.                        x, offset, index);

  1090.                 continue;

  1091.             }

  1092. 

  1093.             index_table->ptses[index] = x;

  1094.             max_temporal_offset = FFMAX(max_temporal_offset, offset);

  1095.         }

  1096.     }

  1097. 

  1098.     index_table->first_dts = -max_temporal_offset;

  1099. 

  1100.     return 0;

  1101. }

  1102. 

  1103. /**

  1104.  * Sorts and collects index table segments into index tables.

  1105.  * Also computes PTSes if possible.

  1106.  */

  1107. static int mxf_compute_index_tables(MXFContext *mxf)

  1108. {

  1109.     int i, j, k, ret, nb_sorted_segments;

  1110.     MXFIndexTableSegment **sorted_segments = NULL;

  1111. 

  1112.     if ((ret = mxf_get_sorted_table_segments(mxf, &nb_sorted_segments, &sorted_segments)) ||

  1113.         nb_sorted_segments <= 0) {

  1114.         av_log(mxf->fc, AV_LOG_WARNING, "broken or empty index\n");

  1115.         return 0;

  1116.     }

  1117. 

  1118.     /* sanity check and count unique BodySIDs/IndexSIDs */

  1119.     for (i = 0; i < nb_sorted_segments; i++) {

  1120.         if (i == 0 || sorted_segments[i-1]->index_sid != sorted_segments[i]->index_sid)

  1121.             mxf->nb_index_tables++;

  1122.         else if (sorted_segments[i-1]->body_sid != sorted_segments[i]->body_sid) {

  1123.             av_log(mxf->fc, AV_LOG_ERROR, "found inconsistent BodySID\n");

  1124.             ret = AVERROR_INVALIDDATA;

  1125.             goto finish_decoding_index;

  1126.         }

  1127.     }

  1128. 

  1129.     if (!(mxf->index_tables = av_calloc(mxf->nb_index_tables, sizeof(MXFIndexTable)))) {

  1130.         av_log(mxf->fc, AV_LOG_ERROR, "failed to allocate index tables\n");

  1131.         ret = AVERROR(ENOMEM);

  1132.         goto finish_decoding_index;

  1133.     }

  1134. 

  1135.     /* distribute sorted segments to index tables */

  1136.     for (i = j = 0; i < nb_sorted_segments; i++) {

  1137.         if (i != 0 && sorted_segments[i-1]->index_sid != sorted_segments[i]->index_sid) {

  1138.             /* next IndexSID */

  1139.             j++;

  1140.         }

  1141. 

  1142.         mxf->index_tables[j].nb_segments++;

  1143.     }

  1144. 

  1145.     for (i = j = 0; j < mxf->nb_index_tables; i += mxf->index_tables[j++].nb_segments) {

  1146.         MXFIndexTable *t = &mxf->index_tables[j];

  1147. 

  1148.         if (!(t->segments = av_calloc(t->nb_segments, sizeof(MXFIndexTableSegment*)))) {

  1149.             av_log(mxf->fc, AV_LOG_ERROR, "failed to allocate IndexTableSegment pointer array\n");

  1150.             ret = AVERROR(ENOMEM);

  1151.             goto finish_decoding_index;

  1152.         }

  1153. 

  1154.         if (sorted_segments[i]->index_start_position)

  1155.             av_log(mxf->fc, AV_LOG_WARNING, "IndexSID %i starts at EditUnit %"PRId64" - seeking may not work as expected\n",

  1156.                    sorted_segments[i]->index_sid, sorted_segments[i]->index_start_position);

  1157. 

  1158.         memcpy(t->segments, &sorted_segments[i], t->nb_segments * sizeof(MXFIndexTableSegment*));

  1159.         t->index_sid = sorted_segments[i]->index_sid;

  1160.         t->body_sid = sorted_segments[i]->body_sid;

  1161. 

  1162.         if ((ret = mxf_compute_ptses_fake_index(mxf, t)) < 0)

  1163.             goto finish_decoding_index;

  1164. 

  1165.         /* fix zero IndexDurations */

  1166.         for (k = 0; k < t->nb_segments; k++) {

  1167.             if (t->segments[k]->index_duration)

  1168.                 continue;

  1169. 

  1170.             if (t->nb_segments > 1)

  1171.                 av_log(mxf->fc, AV_LOG_WARNING, "IndexSID %i segment %i has zero IndexDuration and there's more than one segment\n",

  1172.                        t->index_sid, k);

  1173. 

  1174.             if (mxf->fc->nb_streams <= 0) {

  1175.                 av_log(mxf->fc, AV_LOG_WARNING, "no streams?\n");

  1176.                 break;

  1177.             }

  1178. 

  1179.             /* assume the first stream's duration is reasonable

  1180.              * leave index_duration = 0 on further segments in case we have any (unlikely)

  1181.              */

  1182.             t->segments[k]->index_duration = mxf->fc->streams[0]->duration;

  1183.             break;

  1184.         }

  1185.     }

  1186. 

  1187.     ret = 0;

  1188. finish_decoding_index:

  1189.     av_free(sorted_segments);

  1190.     return ret;

  1191. }

  1192. 

  1193. static int mxf_parse_structural_metadata(MXFContext *mxf)

  1194. {

  1195.     MXFPackage *material_package = NULL;

  1196.     MXFPackage *temp_package = NULL;

  1197.     int i, j, k, ret;

  1198. 

  1199.     av_dlog(mxf->fc, "metadata sets count %d\n", mxf->metadata_sets_count);

  1200.     /* TODO: handle multiple material packages (OP3x) */

  1201.     for (i = 0; i < mxf->packages_count; i++) {

  1202.         material_package = mxf_resolve_strong_ref(mxf, &mxf->packages_refs[i], MaterialPackage);

  1203.         if (material_package) break;

  1204.     }

  1205.     if (!material_package) {

  1206.         av_log(mxf->fc, AV_LOG_ERROR, "no material package found\n");

  1207.         return -1;

  1208.     }

  1209. 

  1210.     for (i = 0; i < material_package->tracks_count; i++) {

  1211.         MXFPackage *source_package = NULL;

  1212.         MXFTrack *material_track = NULL;

  1213.         MXFTrack *source_track = NULL;

  1214.         MXFTrack *temp_track = NULL;

  1215.         MXFDescriptor *descriptor = NULL;

  1216.         MXFStructuralComponent *component = NULL;

  1217.         UID *essence_container_ul = NULL;

  1218.         const MXFCodecUL *codec_ul = NULL;

  1219.         const MXFCodecUL *container_ul = NULL;

  1220.         AVStream *st;

  1221. 

  1222.         if (!(material_track = mxf_resolve_strong_ref(mxf, &material_package->tracks_refs[i], Track))) {

  1223.             av_log(mxf->fc, AV_LOG_ERROR, "could not resolve material track strong ref\n");

  1224.             continue;

  1225.         }

  1226. 

  1227.         if (!(material_track->sequence = mxf_resolve_strong_ref(mxf, &material_track->sequence_ref, Sequence))) {

  1228.             av_log(mxf->fc, AV_LOG_ERROR, "could not resolve material track sequence strong ref\n");

  1229.             continue;

  1230.         }

  1231. 

  1232.         /* TODO: handle multiple source clips */

  1233.         for (j = 0; j < material_track->sequence->structural_components_count; j++) {

  1234.             /* TODO: handle timecode component */

  1235.             component = mxf_resolve_strong_ref(mxf, &material_track->sequence->structural_components_refs[j], SourceClip);

  1236.             if (!component)

  1237.                 continue;

  1238. 

  1239.             for (k = 0; k < mxf->packages_count; k++) {

  1240.                 temp_package = mxf_resolve_strong_ref(mxf, &mxf->packages_refs[k], SourcePackage);

  1241.                 if (!temp_package)

  1242.                     continue;

  1243.                 if (!memcmp(temp_package->package_uid, component->source_package_uid, 16)) {

  1244.                     source_package = temp_package;

  1245.                     break;

  1246.                 }

  1247.             }

  1248.             if (!source_package) {

  1249.                 av_dlog(mxf->fc, "material track %d: no corresponding source package found\n", material_track->track_id);

  1250.                 break;

  1251.             }

  1252.             for (k = 0; k < source_package->tracks_count; k++) {

  1253.                 if (!(temp_track = mxf_resolve_strong_ref(mxf, &source_package->tracks_refs[k], Track))) {

  1254.                     av_log(mxf->fc, AV_LOG_ERROR, "could not resolve source track strong ref\n");

  1255.                     ret = -1;

  1256.                     goto fail_and_free;

  1257.                 }

  1258.                 if (temp_track->track_id == component->source_track_id) {

  1259.                     source_track = temp_track;

  1260.                     break;

  1261.                 }

  1262.             }

  1263.             if (!source_track) {

  1264.                 av_log(mxf->fc, AV_LOG_ERROR, "material track %d: no corresponding source track found\n", material_track->track_id);

  1265.                 break;

  1266.             }

  1267.         }

  1268.         if (!source_track)

  1269.             continue;

  1270. 

  1271.         if (!(source_track->sequence = mxf_resolve_strong_ref(mxf, &source_track->sequence_ref, Sequence))) {

  1272.             av_log(mxf->fc, AV_LOG_ERROR, "could not resolve source track sequence strong ref\n");

  1273.             ret = -1;

  1274.             goto fail_and_free;

  1275.         }

  1276. 

  1277.         /* 0001GL00.MXF.A1.mxf_opatom.mxf has the same SourcePackageID as 0001GL.MXF.V1.mxf_opatom.mxf

  1278.          * This would result in both files appearing to have two streams. Work around this by sanity checking DataDefinition */

  1279.         if (memcmp(material_track->sequence->data_definition_ul, source_track->sequence->data_definition_ul, 16)) {

  1280.             av_log(mxf->fc, AV_LOG_ERROR, "material track %d: DataDefinition mismatch\n", material_track->track_id);

  1281.             continue;

  1282.         }

  1283. 

  1284.         st = avformat_new_stream(mxf->fc, NULL);

  1285.         if (!st) {

  1286.             av_log(mxf->fc, AV_LOG_ERROR, "could not allocate stream\n");

  1287.             ret = AVERROR(ENOMEM);

  1288.             goto fail_and_free;

  1289.         }

  1290.         st->id = source_track->track_id;

  1291.         st->priv_data = source_track;

  1292.         st->duration = component->duration;

  1293.         if (st->duration == -1)

  1294.             st->duration = AV_NOPTS_VALUE;

  1295.         st->start_time = component->start_position;

  1296.         avpriv_set_pts_info(st, 64, material_track->edit_rate.num, material_track->edit_rate.den);

  1297. 

  1298.         PRINT_KEY(mxf->fc, "data definition   ul", source_track->sequence->data_definition_ul);

  1299.         codec_ul = mxf_get_codec_ul(ff_mxf_data_definition_uls, &source_track->sequence->data_definition_ul);

  1300.         st->codec->codec_type = codec_ul->id;

  1301. 

  1302.         source_package->descriptor = mxf_resolve_strong_ref(mxf, &source_package->descriptor_ref, AnyType);

  1303.         if (source_package->descriptor) {

  1304.             if (source_package->descriptor->type == MultipleDescriptor) {

  1305.                 for (j = 0; j < source_package->descriptor->sub_descriptors_count; j++) {

  1306.                     MXFDescriptor *sub_descriptor = mxf_resolve_strong_ref(mxf, &source_package->descriptor->sub_descriptors_refs[j], Descriptor);

  1307. 

  1308.                     if (!sub_descriptor) {

  1309.                         av_log(mxf->fc, AV_LOG_ERROR, "could not resolve sub descriptor strong ref\n");

  1310.                         continue;

  1311.                     }

  1312.                     if (sub_descriptor->linked_track_id == source_track->track_id) {

  1313.                         descriptor = sub_descriptor;

  1314.                         break;

  1315.                     }

  1316.                 }

  1317.             } else if (source_package->descriptor->type == Descriptor)

  1318.                 descriptor = source_package->descriptor;

  1319.         }

  1320.         if (!descriptor) {

  1321.             av_log(mxf->fc, AV_LOG_INFO, "source track %d: stream %d, no descriptor found\n", source_track->track_id, st->index);

  1322.             continue;

  1323.         }

  1324.         PRINT_KEY(mxf->fc, "essence codec     ul", descriptor->essence_codec_ul);

  1325.         PRINT_KEY(mxf->fc, "essence container ul", descriptor->essence_container_ul);

  1326.         essence_container_ul = &descriptor->essence_container_ul;

  1327.         /* HACK: replacing the original key with mxf_encrypted_essence_container

  1328.          * is not allowed according to s429-6, try to find correct information anyway */

  1329.         if (IS_KLV_KEY(essence_container_ul, mxf_encrypted_essence_container)) {

  1330.             av_log(mxf->fc, AV_LOG_INFO, "broken encrypted mxf file\n");

  1331.             for (k = 0; k < mxf->metadata_sets_count; k++) {

  1332.                 MXFMetadataSet *metadata = mxf->metadata_sets[k];

  1333.                 if (metadata->type == CryptoContext) {

  1334.                     essence_container_ul = &((MXFCryptoContext *)metadata)->source_container_ul;

  1335.                     break;

  1336.                 }

  1337.             }

  1338.         }

  1339. 

  1340.         /* TODO: drop PictureEssenceCoding and SoundEssenceCompression, only check EssenceContainer */

  1341.         codec_ul = mxf_get_codec_ul(ff_mxf_codec_uls, &descriptor->essence_codec_ul);

  1342.         st->codec->codec_id = codec_ul->id;

  1343.         if (descriptor->extradata) {

  1344.             st->codec->extradata = descriptor->extradata;

  1345.             st->codec->extradata_size = descriptor->extradata_size;

  1346.         }

  1347.         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

  1348.             container_ul = mxf_get_codec_ul(mxf_picture_essence_container_uls, essence_container_ul);

  1349.             if (st->codec->codec_id == CODEC_ID_NONE)

  1350.                 st->codec->codec_id = container_ul->id;

  1351.             st->codec->width = descriptor->width;

  1352.             st->codec->height = descriptor->height;

  1353.             if (st->codec->codec_id == CODEC_ID_RAWVIDEO)

  1354.                 st->codec->pix_fmt = descriptor->pix_fmt;

  1355.             st->need_parsing = AVSTREAM_PARSE_HEADERS;

  1356.         } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {

  1357.             container_ul = mxf_get_codec_ul(mxf_sound_essence_container_uls, essence_container_ul);

  1358.             if (st->codec->codec_id == CODEC_ID_NONE)

  1359.                 st->codec->codec_id = container_ul->id;

  1360.             st->codec->channels = descriptor->channels;

  1361.             st->codec->bits_per_coded_sample = descriptor->bits_per_sample;

  1362.             st->codec->sample_rate = descriptor->sample_rate.num / descriptor->sample_rate.den;

  1363.             /* TODO: implement CODEC_ID_RAWAUDIO */

  1364.             if (st->codec->codec_id == CODEC_ID_PCM_S16LE) {

  1365.                 if (descriptor->bits_per_sample > 16 && descriptor->bits_per_sample <= 24)

  1366.                     st->codec->codec_id = CODEC_ID_PCM_S24LE;

  1367.                 else if (descriptor->bits_per_sample == 32)

  1368.                     st->codec->codec_id = CODEC_ID_PCM_S32LE;

  1369.             } else if (st->codec->codec_id == CODEC_ID_PCM_S16BE) {

  1370.                 if (descriptor->bits_per_sample > 16 && descriptor->bits_per_sample <= 24)

  1371.                     st->codec->codec_id = CODEC_ID_PCM_S24BE;

  1372.                 else if (descriptor->bits_per_sample == 32)

  1373.                     st->codec->codec_id = CODEC_ID_PCM_S32BE;

  1374.             } else if (st->codec->codec_id == CODEC_ID_MP2) {

  1375.                 st->need_parsing = AVSTREAM_PARSE_FULL;

  1376.             }

  1377.         }

  1378.         if (st->codec->codec_type != AVMEDIA_TYPE_DATA && (*essence_container_ul)[15] > 0x01) {

  1379.             /* TODO: decode timestamps */

  1380.             st->need_parsing = AVSTREAM_PARSE_TIMESTAMPS;

  1381.         }

  1382.     }

  1383. 

  1384.     ret = 0;

  1385. fail_and_free:

  1386.     return ret;

  1387. }

  1388. 

  1389. static const MXFMetadataReadTableEntry mxf_metadata_read_table[] = {

  1390.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x05,0x01,0x00 }, mxf_read_primer_pack },

  1391.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x02,0x01,0x00 }, mxf_read_partition_pack },

  1392.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x02,0x02,0x00 }, mxf_read_partition_pack },

  1393.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x02,0x03,0x00 }, mxf_read_partition_pack },

  1394.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x02,0x04,0x00 }, mxf_read_partition_pack },

  1395.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x03,0x01,0x00 }, mxf_read_partition_pack },

  1396.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x03,0x02,0x00 }, mxf_read_partition_pack },

  1397.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x03,0x03,0x00 }, mxf_read_partition_pack },

  1398.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x03,0x04,0x00 }, mxf_read_partition_pack },

  1399.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x04,0x02,0x00 }, mxf_read_partition_pack },

  1400.     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x04,0x04,0x00 }, mxf_read_partition_pack },

  1401.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x18,0x00 }, mxf_read_content_storage, 0, AnyType },

  1402.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x37,0x00 }, mxf_read_source_package, sizeof(MXFPackage), SourcePackage },

  1403.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x36,0x00 }, mxf_read_material_package, sizeof(MXFPackage), MaterialPackage },

  1404.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x0F,0x00 }, mxf_read_sequence, sizeof(MXFSequence), Sequence },

  1405.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x11,0x00 }, mxf_read_source_clip, sizeof(MXFStructuralComponent), SourceClip },

  1406.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x44,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), MultipleDescriptor },

  1407.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x42,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* Generic Sound */

  1408.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x28,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* CDCI */

  1409.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x29,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* RGBA */

  1410.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x51,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* MPEG 2 Video */

  1411.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x48,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* Wave */

  1412.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x47,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* AES3 */

  1413.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x3A,0x00 }, mxf_read_track, sizeof(MXFTrack), Track }, /* Static Track */

  1414.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x3B,0x00 }, mxf_read_track, sizeof(MXFTrack), Track }, /* Generic Track */

  1415.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x04,0x01,0x02,0x02,0x00,0x00 }, mxf_read_cryptographic_context, sizeof(MXFCryptoContext), CryptoContext },

  1416.     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x10,0x01,0x00 }, mxf_read_index_table_segment, sizeof(MXFIndexTableSegment), IndexTableSegment },

  1417.     { { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }, NULL, 0, AnyType },

  1418. };

  1419. 

  1420. static int mxf_read_local_tags(MXFContext *mxf, KLVPacket *klv, MXFMetadataReadFunc *read_child, int ctx_size, enum MXFMetadataSetType type)

  1421. {

  1422.     AVIOContext *pb = mxf->fc->pb;

  1423.     MXFMetadataSet *ctx = ctx_size ? av_mallocz(ctx_size) : mxf;

  1424.     uint64_t klv_end = avio_tell(pb) + klv->length;

  1425. 

  1426.     if (!ctx)

  1427.         return -1;

  1428.     while (avio_tell(pb) + 4 < klv_end) {

  1429.         int tag = avio_rb16(pb);

  1430.         int size = avio_rb16(pb); /* KLV specified by 0x53 */

  1431.         uint64_t next = avio_tell(pb) + size;

  1432.         UID uid = {0};

  1433. 

  1434.         av_dlog(mxf->fc, "local tag %#04x size %d\n", tag, size);

  1435.         if (!size) { /* ignore empty tag, needed for some files with empty UMID tag */

  1436.             av_log(mxf->fc, AV_LOG_ERROR, "local tag %#04x with 0 size\n", tag);

  1437.             continue;

  1438.         }

  1439.         if (tag > 0x7FFF) { /* dynamic tag */

  1440.             int i;

  1441.             for (i = 0; i < mxf->local_tags_count; i++) {

  1442.                 int local_tag = AV_RB16(mxf->local_tags+i*18);

  1443.                 if (local_tag == tag) {

  1444.                     memcpy(uid, mxf->local_tags+i*18+2, 16);

  1445.                     av_dlog(mxf->fc, "local tag %#04x\n", local_tag);

  1446.                     PRINT_KEY(mxf->fc, "uid", uid);

  1447.                 }

  1448.             }

  1449.         }

  1450.         if (ctx_size && tag == 0x3C0A)

  1451.             avio_read(pb, ctx->uid, 16);

  1452.         else if (read_child(ctx, pb, tag, size, uid, -1) < 0)

  1453.             return -1;

  1454. 

  1455.         avio_seek(pb, next, SEEK_SET);

  1456.     }

  1457.     if (ctx_size) ctx->type = type;

  1458.     return ctx_size ? mxf_add_metadata_set(mxf, ctx) : 0;

  1459. }

  1460. 

  1461. /**

  1462.  * Seeks to the previous partition, if possible

  1463.  * @return <= 0 if we should stop parsing, > 0 if we should keep going

  1464.  */

  1465. static int mxf_seek_to_previous_partition(MXFContext *mxf)

  1466. {

  1467.     AVIOContext *pb = mxf->fc->pb;

  1468. 

  1469.     if (!mxf->current_partition ||

  1470.         mxf->run_in + mxf->current_partition->previous_partition <= mxf->last_forward_tell)

  1471.         return 0;   /* we've parsed all partitions */

  1472. 

  1473.     /* seek to previous partition */

  1474.     avio_seek(pb, mxf->run_in + mxf->current_partition->previous_partition, SEEK_SET);

  1475.     mxf->current_partition = NULL;

  1476. 

  1477.     av_dlog(mxf->fc, "seeking to previous partition\n");

  1478. 

  1479.     return 1;

  1480. }

  1481. 

  1482. /**

  1483.  * Called when essence is encountered

  1484.  * @return <= 0 if we should stop parsing, > 0 if we should keep going

  1485.  */

  1486. static int mxf_parse_handle_essence(MXFContext *mxf)

  1487. {

  1488.     AVIOContext *pb = mxf->fc->pb;

  1489.     int64_t ret;

  1490. 

  1491.     if (!mxf->current_partition) {

  1492.         av_log(mxf->fc, AV_LOG_ERROR, "found essence prior to PartitionPack\n");

  1493.         return AVERROR_INVALIDDATA;

  1494.     }

  1495. 

  1496.     if (mxf->parsing_backward) {

  1497.         return mxf_seek_to_previous_partition(mxf);

  1498.     } else {

  1499.         if (!mxf->footer_partition) {

  1500.             av_dlog(mxf->fc, "no footer\n");

  1501.             return 0;

  1502.         }

  1503. 

  1504.         av_dlog(mxf->fc, "seeking to footer\n");

  1505. 

  1506.         /* remember where we were so we don't end up seeking further back than this */

  1507.         mxf->last_forward_tell = avio_tell(pb);

  1508. 

  1509.         if (!pb->seekable) {

  1510.             av_log(mxf->fc, AV_LOG_INFO, "file is not seekable - not parsing footer\n");

  1511.             return -1;

  1512.         }

  1513. 

  1514.         /* seek to footer partition and parse backward */

  1515.         if ((ret = avio_seek(pb, mxf->run_in + mxf->footer_partition, SEEK_SET)) < 0) {

  1516.             av_log(mxf->fc, AV_LOG_ERROR, "failed to seek to footer @ 0x%"PRIx64" (%"PRId64") - partial file?\n",

  1517.                    mxf->run_in + mxf->footer_partition, ret);

  1518.             return ret;

  1519.         }

  1520. 

  1521.         mxf->current_partition = NULL;

  1522.         mxf->parsing_backward = 1;

  1523.     }

  1524. 

  1525.     return 1;

  1526. }

  1527. 

  1528. /**

  1529.  * Called when the next partition or EOF is encountered

  1530.  * @return <= 0 if we should stop parsing, > 0 if we should keep going

  1531.  */

  1532. static int mxf_parse_handle_partition_or_eof(MXFContext *mxf)

  1533. {

  1534.     return mxf->parsing_backward ? mxf_seek_to_previous_partition(mxf) : 1;

  1535. }

  1536. 

  1537. /**

  1538.  * Figures out the proper offset and length of the essence container in each partition

  1539.  */

  1540. static void mxf_compute_essence_containers(MXFContext *mxf)

  1541. {

  1542.     int x;

  1543. 

  1544.     /* everything is already correct */

  1545.     if (mxf->op == OPAtom)

  1546.         return;

  1547. 

  1548.     for (x = 0; x < mxf->partitions_count; x++) {

  1549.         MXFPartition *p = &mxf->partitions[x];

  1550. 

  1551.         if (!p->body_sid)

  1552.             continue;       /* BodySID == 0 -> no essence */

  1553. 

  1554.         if (x >= mxf->partitions_count - 1)

  1555.             break;          /* last partition - can't compute length (and we don't need to) */

  1556. 

  1557.         /* essence container spans to the next partition */

  1558.         p->essence_length = mxf->partitions[x+1].this_partition - p->essence_offset;

  1559. 

  1560.         if (p->essence_length < 0) {

  1561.             /* next ThisPartition < essence_offset */

  1562.             p->essence_length = 0;

  1563.             av_log(mxf->fc, AV_LOG_ERROR, "partition %i: bad ThisPartition = %lx\n",

  1564.                    x+1, mxf->partitions[x+1].this_partition);

  1565.         }

  1566.     }

  1567. }

  1568. 

  1569. static int64_t round_to_kag(int64_t position, int kag_size)

  1570. {

  1571.     /* TODO: account for run-in? the spec isn't clear whether KAG should account for it */

  1572.     /* NOTE: kag_size may be any integer between 1 - 2^10 */

  1573.     int64_t ret = (position / kag_size) * kag_size;

  1574.     return ret == position ? ret : ret + kag_size;

  1575. }

  1576. 

  1577. static int mxf_read_header(AVFormatContext *s, AVFormatParameters *ap)

  1578. {

  1579.     MXFContext *mxf = s->priv_data;

  1580.     KLVPacket klv;

  1581.     int64_t essence_offset = 0;

  1582.     int ret;

  1583. 

  1584.     mxf->last_forward_tell = INT64_MAX;

  1585. 

  1586.     if (!mxf_read_sync(s->pb, mxf_header_partition_pack_key, 14)) {

  1587.         av_log(s, AV_LOG_ERROR, "could not find header partition pack key\n");

  1588.         return -1;

  1589.     }

  1590.     avio_seek(s->pb, -14, SEEK_CUR);

  1591.     mxf->fc = s;

  1592.     mxf->run_in = avio_tell(s->pb);

  1593. 

  1594.     while (!url_feof(s->pb)) {

  1595.         const MXFMetadataReadTableEntry *metadata;

  1596. 

  1597.         if (klv_read_packet(&klv, s->pb) < 0) {

  1598.             /* EOF - seek to previous partition or stop */

  1599.             if(mxf_parse_handle_partition_or_eof(mxf) <= 0)

  1600.                 break;

  1601.             else

  1602.                 continue;

  1603.         }

  1604. 

  1605.         PRINT_KEY(s, "read header", klv.key);

  1606.         av_dlog(s, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset);

  1607.         if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key) ||

  1608.             IS_KLV_KEY(klv.key, mxf_essence_element_key) ||

  1609.             IS_KLV_KEY(klv.key, mxf_avid_essence_element_key) ||

  1610.             IS_KLV_KEY(klv.key, mxf_system_item_key)) {

  1611.             if (!mxf->current_partition->essence_offset) {

  1612.                 /* for OP1a we compute essence_offset

  1613.                  * for OPAtom we point essence_offset after the KL (usually op1a_essence_offset + 20 or 25)

  1614.                  * TODO: for OP1a we could eliminate this entire if statement, always stopping parsing at op1a_essence_offset

  1615.                  *       for OPAtom we still need the actual essence_offset though (the KL's length can vary)

  1616.                  */

  1617.                 int64_t op1a_essence_offset =

  1618.                     round_to_kag(mxf->current_partition->this_partition +

  1619.                                  mxf->current_partition->pack_length,       mxf->current_partition->kag_size) +

  1620.                     round_to_kag(mxf->current_partition->header_byte_count, mxf->current_partition->kag_size) +

  1621.                     round_to_kag(mxf->current_partition->index_byte_count,  mxf->current_partition->kag_size);

  1622. 

  1623.                 if (mxf->op == OPAtom) {

  1624.                     /* point essence_offset to the actual data

  1625.                     * OPAtom has all the essence in one big KLV

  1626.                     */

  1627.                     mxf->current_partition->essence_offset = avio_tell(s->pb);

  1628.                     mxf->current_partition->essence_length = klv.length;

  1629.                 } else {

  1630.                     /* NOTE: op1a_essence_offset may be less than to klv.offset (C0023S01.mxf)  */

  1631.                     mxf->current_partition->essence_offset = op1a_essence_offset;

  1632.                 }

  1633.             }

  1634. 

  1635.             if (!essence_offset)

  1636.                 essence_offset = klv.offset;

  1637. 

  1638.             /* seek to footer, previous partition or stop */

  1639.             if (mxf_parse_handle_essence(mxf) <= 0)

  1640.                 break;

  1641.             continue;

  1642.         } else if (!memcmp(klv.key, mxf_header_partition_pack_key, 13) &&

  1643.                    klv.key[13] >= 2 && klv.key[13] <= 4 && mxf->current_partition) {

  1644.             /* next partition pack - keep going, seek to previous partition or stop */

  1645.             if(mxf_parse_handle_partition_or_eof(mxf) <= 0)

  1646.                 break;

  1647.         }

  1648. 

  1649.         for (metadata = mxf_metadata_read_table; metadata->read; metadata++) {

  1650.             if (IS_KLV_KEY(klv.key, metadata->key)) {

  1651.                 int res;

  1652.                 if (klv.key[5] == 0x53) {

  1653.                     res = mxf_read_local_tags(mxf, &klv, metadata->read, metadata->ctx_size, metadata->type);

  1654.                 } else {

  1655.                     uint64_t next = avio_tell(s->pb) + klv.length;

  1656.                     res = metadata->read(mxf, s->pb, 0, klv.length, klv.key, klv.offset);

  1657.                     avio_seek(s->pb, next, SEEK_SET);

  1658.                 }

  1659.                 if (res < 0) {

  1660.                     av_log(s, AV_LOG_ERROR, "error reading header metadata\n");

  1661.                     return -1;

  1662.                 }

  1663.                 break;

  1664.             }

  1665.         }

  1666.         if (!metadata->read)

  1667.             avio_skip(s->pb, klv.length);

  1668.     }

  1669.     /* FIXME avoid seek */

  1670.     if (!essence_offset)  {

  1671.         av_log(s, AV_LOG_ERROR, "no essence\n");

  1672.         return AVERROR_INVALIDDATA;

  1673.     }

  1674.     avio_seek(s->pb, essence_offset, SEEK_SET);

  1675. 

  1676.     mxf_compute_essence_containers(mxf);

  1677. 

  1678.     /* we need to do this before computing the index tables

  1679.      * to be able to fill in zero IndexDurations with st->duration */

  1680.     if ((ret = mxf_parse_structural_metadata(mxf)) < 0)

  1681.         return ret;

  1682. 

  1683.     if ((ret = mxf_compute_index_tables(mxf)) < 0)

  1684.         return ret;

  1685. 

  1686.     if (mxf->nb_index_tables > 1) {

  1687.         /* TODO: look up which IndexSID to use via EssenceContainerData */

  1688.         av_log(mxf->fc, AV_LOG_INFO, "got %i index tables - only the first one (IndexSID %i) will be used\n",

  1689.                mxf->nb_index_tables, mxf->index_tables[0].index_sid);

  1690.     } else if (mxf->nb_index_tables == 0 && mxf->op == OPAtom) {

  1691.         av_log(mxf->fc, AV_LOG_ERROR, "cannot demux OPAtom without an index\n");

  1692.         return AVERROR_INVALIDDATA;

  1693.     }

  1694. 

  1695.     return 0;

  1696. }

  1697. 

  1698. /**

  1699.  * Computes DTS and PTS for the given video packet based on its offset.

  1700.  */

  1701. static void mxf_packet_timestamps(MXFContext *mxf, AVPacket *pkt)

  1702. {

  1703.     int64_t next_ofs;

  1704.     MXFIndexTable *t = &mxf->index_tables[0];

  1705. 

  1706.     /* this is called from the OP1a demuxing logic, which means there may be no index tables */

  1707.     if (mxf->nb_index_tables <= 0)

  1708.         return;

  1709. 

  1710.     /* find mxf->current_edit_unit so that the next edit unit starts ahead of pkt->pos */

  1711.     for (;;) {

  1712.         if (mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit + 1, NULL, &next_ofs, 0) < 0)

  1713.             break;

  1714. 

  1715.         if (next_ofs > pkt->pos)

  1716.             break;

  1717. 

  1718.         mxf->current_edit_unit++;

  1719.     }

  1720. 

  1721.     if (mxf->current_edit_unit >= t->nb_ptses)

  1722.         return;

  1723. 

  1724.     pkt->dts = mxf->current_edit_unit + t->first_dts;

  1725.     pkt->pts = t->ptses[mxf->current_edit_unit];

  1726. }

  1727. 

  1728. static int mxf_read_packet_old(AVFormatContext *s, AVPacket *pkt)

  1729. {

  1730.     KLVPacket klv;

  1731. 

  1732.     while (!url_feof(s->pb)) {

  1733.         if (klv_read_packet(&klv, s->pb) < 0)

  1734.             return -1;

  1735.         PRINT_KEY(s, "read packet", klv.key);

  1736.         av_dlog(s, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset);

  1737.         if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key)) {

  1738.             int res = mxf_decrypt_triplet(s, pkt, &klv);

  1739.             if (res < 0) {

  1740.                 av_log(s, AV_LOG_ERROR, "invalid encoded triplet\n");

  1741.                 return -1;

  1742.             }

  1743.             return 0;

  1744.         }

  1745.         if (IS_KLV_KEY(klv.key, mxf_essence_element_key) ||

  1746.             IS_KLV_KEY(klv.key, mxf_avid_essence_element_key)) {

  1747.             int index = mxf_get_stream_index(s, &klv);

  1748.             if (index < 0) {

  1749.                 av_log(s, AV_LOG_ERROR, "error getting stream index %d\n", AV_RB32(klv.key+12));

  1750.                 goto skip;

  1751.             }

  1752.             if (s->streams[index]->discard == AVDISCARD_ALL)

  1753.                 goto skip;

  1754.             /* check for 8 channels AES3 element */

  1755.             if (klv.key[12] == 0x06 && klv.key[13] == 0x01 && klv.key[14] == 0x10) {

  1756.                 if (mxf_get_d10_aes3_packet(s->pb, s->streams[index], pkt, klv.length) < 0) {

  1757.                     av_log(s, AV_LOG_ERROR, "error reading D-10 aes3 frame\n");

  1758.                     return -1;

  1759.                 }

  1760.             } else {

  1761.                 int ret = av_get_packet(s->pb, pkt, klv.length);

  1762.                 if (ret < 0)

  1763.                     return ret;

  1764.             }

  1765.             pkt->stream_index = index;

  1766.             pkt->pos = klv.offset;

  1767. 

  1768.             if (s->streams[index]->codec->codec_type == AVMEDIA_TYPE_VIDEO)

  1769.                 mxf_packet_timestamps(s->priv_data, pkt);   /* offset -> EditUnit -> DTS/PTS */

  1770. 

  1771.             return 0;

  1772.         } else

  1773.         skip:

  1774.             avio_skip(s->pb, klv.length);

  1775.     }

  1776.     return AVERROR_EOF;

  1777. }

  1778. 

  1779. static int mxf_read_packet(AVFormatContext *s, AVPacket *pkt)

  1780. {

  1781.     MXFContext *mxf = s->priv_data;

  1782.     int ret, size;

  1783.     int64_t ret64, pos, next_pos;

  1784.     AVStream *st;

  1785.     MXFIndexTable *t;

  1786. 

  1787.     if (mxf->op != OPAtom)

  1788.         return mxf_read_packet_old(s, pkt);

  1789. 

  1790.     /* OPAtom - clip wrapped demuxing */

  1791.     /* NOTE: mxf_read_header() makes sure nb_index_tables > 0 for OPAtom */

  1792.     st = s->streams[0];

  1793.     t = &mxf->index_tables[0];

  1794. 

  1795.     if (mxf->current_edit_unit >= st->duration)

  1796.         return AVERROR_EOF;

  1797. 

  1798.     if ((ret = mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit, NULL, &pos, 1)) < 0)

  1799.         return ret;

  1800. 

  1801.     /* compute size by finding the next edit unit or the end of the essence container

  1802.      * not pretty, but it works */

  1803.     if ((ret = mxf_edit_unit_absolute_offset(mxf, t, mxf->current_edit_unit + 1, NULL, &next_pos, 0)) < 0 &&

  1804.         (next_pos = mxf_essence_container_end(mxf, t->body_sid)) <= 0) {

  1805.         av_log(s, AV_LOG_ERROR, "unable to compute the size of the last packet\n");

  1806.         return AVERROR_INVALIDDATA;

  1807.     }

  1808. 

  1809.     if ((size = next_pos - pos) <= 0) {

  1810.         av_log(s, AV_LOG_ERROR, "bad size: %i\n", size);

  1811.         return AVERROR_INVALIDDATA;

  1812.     }

  1813. 

  1814.     if ((ret64 = avio_seek(s->pb, pos, SEEK_SET)) < 0)

  1815.         return ret64;

  1816. 

  1817.         if ((ret = av_get_packet(s->pb, pkt, size)) != size)

  1818.             return ret < 0 ? ret : AVERROR_EOF;

  1819. 

  1820.     if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO && t->ptses &&

  1821.         mxf->current_edit_unit >= 0 && mxf->current_edit_unit < t->nb_ptses) {

  1822.         pkt->dts = mxf->current_edit_unit + t->first_dts;

  1823.         pkt->pts = t->ptses[mxf->current_edit_unit];

  1824.     }

  1825. 

  1826.     pkt->stream_index = 0;

  1827.     mxf->current_edit_unit++;

  1828. 

  1829.     return 0;

  1830. }

  1831. 

  1832. static int mxf_read_close(AVFormatContext *s)

  1833. {

  1834.     MXFContext *mxf = s->priv_data;

  1835.     MXFIndexTableSegment *seg;

  1836.     int i, j;

  1837. 

  1838.     av_freep(&mxf->packages_refs);

  1839. 

  1840.     for (i = 0; i < s->nb_streams; i++)

  1841.         s->streams[i]->priv_data = NULL;

  1842. 

  1843.     for (i = 0; i < mxf->metadata_sets_count; i++) {

  1844.         switch (mxf->metadata_sets[i]->type) {

  1845.         case MultipleDescriptor:

  1846.             av_freep(&((MXFDescriptor *)mxf->metadata_sets[i])->sub_descriptors_refs);

  1847.             break;

  1848.         case Sequence:

  1849.             av_freep(&((MXFSequence *)mxf->metadata_sets[i])->structural_components_refs);

  1850.             break;

  1851.         case SourcePackage:

  1852.         case MaterialPackage:

  1853.             av_freep(&((MXFPackage *)mxf->metadata_sets[i])->tracks_refs);

  1854.             break;

  1855.         case IndexTableSegment:

  1856.             seg = (MXFIndexTableSegment *)mxf->metadata_sets[i];

  1857.             av_freep(&seg->temporal_offset_entries);

  1858.             av_freep(&seg->flag_entries);

  1859.             av_freep(&seg->stream_offset_entries);

  1860.             break;

  1861.         default:

  1862.             break;

  1863.         }

  1864.         av_freep(&mxf->metadata_sets[i]);

  1865.     }

  1866.     av_freep(&mxf->partitions);

  1867.     av_freep(&mxf->metadata_sets);

  1868.     av_freep(&mxf->aesc);

  1869.     av_freep(&mxf->local_tags);

  1870. 

  1871.     for (i = 0; i < mxf->nb_index_tables; i++) {

  1872.         av_freep(&mxf->index_tables[i].segments);

  1873.         av_freep(&mxf->index_tables[i].fake_index);

  1874.     }

  1875.     av_freep(&mxf->index_tables);

  1876. 

  1877.     return 0;

  1878. }

  1879. 

  1880. static int mxf_probe(AVProbeData *p) {

  1881.     uint8_t *bufp = p->buf;

  1882.     uint8_t *end = p->buf + p->buf_size;

  1883. 

  1884.     if (p->buf_size < sizeof(mxf_header_partition_pack_key))

  1885.         return 0;

  1886. 

  1887.     /* Must skip Run-In Sequence and search for MXF header partition pack key SMPTE 377M 5.5 */

  1888.     end -= sizeof(mxf_header_partition_pack_key);

  1889.     for (; bufp < end; bufp++) {

  1890.         if (IS_KLV_KEY(bufp, mxf_header_partition_pack_key))

  1891.             return AVPROBE_SCORE_MAX;

  1892.     }

  1893.     return 0;

  1894. }

  1895. 

  1896. /* rudimentary byte seek */

  1897. /* XXX: use MXF Index */

  1898. static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_time, int flags)

  1899. {

  1900.     AVStream *st = s->streams[stream_index];

  1901.     int64_t seconds;

  1902.     MXFContext* mxf = s->priv_data;

  1903.     int64_t seekpos;

  1904.     int ret;

  1905.     MXFIndexTable *t;

  1906. 

  1907.     if (mxf->index_tables <= 0) {

  1908.     if (!s->bit_rate)

  1909.         return -1;

  1910.     if (sample_time < 0)

  1911.         sample_time = 0;

  1912.     seconds = av_rescale(sample_time, st->time_base.num, st->time_base.den);

  1913.     if (avio_seek(s->pb, (s->bit_rate * seconds) >> 3, SEEK_SET) < 0)

  1914.         return -1;

  1915.     ff_update_cur_dts(s, st, sample_time);

  1916.     } else {

  1917.         t = &mxf->index_tables[0];

  1918. 

  1919.         /* clamp above zero, else ff_index_search_timestamp() returns negative

  1920.          * this also means we allow seeking before the start */

  1921.         sample_time = FFMAX(sample_time, 0);

  1922. 

  1923.         if (t->fake_index) {

  1924.             /* behave as if we have a proper index */

  1925.             if ((sample_time = ff_index_search_timestamp(t->fake_index, t->nb_ptses, sample_time, flags)) < 0)

  1926.                 return sample_time;

  1927.         } else {

  1928.             /* no IndexEntryArray (one or more CBR segments)

  1929.              * make sure we don't seek past the end */

  1930.             sample_time = FFMIN(sample_time, st->duration - 1);

  1931.         }

  1932. 

  1933.         if ((ret = mxf_edit_unit_absolute_offset(mxf, t, sample_time, &sample_time, &seekpos, 1)) << 0)

  1934.             return ret;

  1935. 

  1936.         av_update_cur_dts(s, st, sample_time);

  1937.         mxf->current_edit_unit = sample_time;

  1938.         avio_seek(s->pb, seekpos, SEEK_SET);

  1939.     }

  1940.     return 0;

  1941. }

  1942. 

  1943. AVInputFormat ff_mxf_demuxer = {

  1944.     .name           = "mxf",

  1945.     .long_name      = NULL_IF_CONFIG_SMALL("Material eXchange Format"),

  1946.     .priv_data_size = sizeof(MXFContext),

  1947.     .read_probe     = mxf_probe,

  1948.     .read_header    = mxf_read_header,

  1949.     .read_packet    = mxf_read_packet,

  1950.     .read_close     = mxf_read_close,

  1951.     .read_seek      = mxf_read_seek,

  1952. };