PeerStreamer

/*

 * MXF demuxer.

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

 *

 * 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

 */

/*

 * References

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

 * SMPTE 377M MXF File Format Specifications

 * SMPTE 378M Operational Pattern 1a

 * SMPTE 379M MXF Generic Container

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

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

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

 *

 * Principle

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

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

 * Material Package contains tracks with reference to SourcePackage tracks.

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

 * Assign Descriptors to correct Tracks.

 *

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

 * Metadata parsing resolves Strong References to objects.

 *

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

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

 */

//#define DEBUG

#include "libavutil/aes.h"

#include "mxf.h"

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

    UID source_container_ul;

} MXFCryptoContext;

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

    UID source_package_uid;

    UID data_definition_ul;

    int64_t duration;

    int64_t start_position;

    int source_track_id;

} MXFStructuralComponent;

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

    UID data_definition_ul;

    UID *structural_components_refs;

    int structural_components_count;

    int64_t duration;

} MXFSequence;

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

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

    UID sequence_ref;

    int track_id;

    uint8_t track_number[4];

    AVRational edit_rate;

} MXFTrack;

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

    UID essence_container_ul;

    UID essence_codec_ul;

    AVRational sample_rate;

    AVRational aspect_ratio;

    int width;

    int height;

    int channels;

    int bits_per_sample;

    UID *sub_descriptors_refs;

    int sub_descriptors_count;

    int linked_track_id;

    uint8_t *extradata;

    int extradata_size;

} MXFDescriptor;

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

    UID package_uid;

    UID *tracks_refs;

    int tracks_count;

    MXFDescriptor *descriptor; /* only one */

    UID descriptor_ref;

} MXFPackage;

typedef struct {

    UID uid;

    enum MXFMetadataSetType type;

} MXFMetadataSet;

typedef struct {

    UID *packages_refs;

    int packages_count;

    MXFMetadataSet **metadata_sets;

    int metadata_sets_count;

    AVFormatContext *fc;

    struct AVAES *aesc;

    uint8_t *local_tags;

    int local_tags_count;

} MXFContext;

enum MXFWrappingScheme {

    Frame,

    Clip,

};

typedef struct {

    const UID key;

    int (*read)();

    int ctx_size;

    enum MXFMetadataSetType type;

} MXFMetadataReadTableEntry;

/* partial keys to match */

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

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

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

/* complete keys to match */

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 };

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

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

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

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

static int64_t klv_decode_ber_length(ByteIOContext *pb)

{

    uint64_t size = get_byte(pb);

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

        int bytes_num = size & 0x7f;

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

        if (bytes_num > 8)

            return -1;

        size = 0;

        while (bytes_num--)

            size = size << 8 | get_byte(pb);

    }

    return size;

}

static int mxf_read_sync(ByteIOContext *pb, const uint8_t *key, unsigned size)

{

    int i, b;

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

        b = get_byte(pb);

        if (b == key[0])

            i = 0;

        else if (b != key[i])

            i = -1;

    }

    return i == size;

}

static int klv_read_packet(KLVPacket *klv, ByteIOContext *pb)

{

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

        return -1;

    klv->offset = url_ftell(pb) - 4;

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

    get_buffer(pb, klv->key + 4, 12);

    klv->length = klv_decode_ber_length(pb);

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

}

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

{

    int i;

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

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

        /* SMPTE 379M 7.3 */

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

            return i;

    }

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

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

}

/* XXX: use AVBitStreamFilter */

static int mxf_get_d10_aes3_packet(ByteIOContext *pb, AVStream *st, AVPacket *pkt, int64_t length)

{

    uint8_t buffer[61444];

    const uint8_t *buf_ptr, *end_ptr;

    uint8_t *data_ptr;

    int i;

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

        return -1;

    get_buffer(pb, buffer, length);

    av_new_packet(pkt, length);

    data_ptr = pkt->data;

    end_ptr = buffer + length;

    buf_ptr = buffer + 4; /* skip SMPTE 331M header */

    for (; buf_ptr < end_ptr; ) {

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

            uint32_t sample = bytestream_get_le32(&buf_ptr);

            if (st->codec->bits_per_sample == 24)

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

            else

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

        }

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

    }

    pkt->size = data_ptr - pkt->data;

    return 0;

}

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

{

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

    MXFContext *mxf = s->priv_data;

    ByteIOContext *pb = s->pb;

    offset_t end = url_ftell(pb) + klv->length;

    uint64_t size;

    uint64_t orig_size;

    uint64_t plaintext_size;

    uint8_t ivec[16];

    uint8_t tmpbuf[16];

    int index;

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

        mxf->aesc = av_malloc(av_aes_size);

        if (!mxf->aesc)

            return -1;

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

    }

    // crypto context

    url_fskip(pb, klv_decode_ber_length(pb));

    // plaintext offset

    klv_decode_ber_length(pb);

    plaintext_size = get_be64(pb);

    // source klv key

    klv_decode_ber_length(pb);

    get_buffer(pb, klv->key, 16);

    if (!IS_KLV_KEY(klv, mxf_essence_element_key))

        return -1;

    index = mxf_get_stream_index(s, klv);

    if (index < 0)

        return -1;

    // source size

    klv_decode_ber_length(pb);

    orig_size = get_be64(pb);

    if (orig_size < plaintext_size)

        return -1;

    // enc. code

    size = klv_decode_ber_length(pb);

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

        return -1;

    get_buffer(pb, ivec, 16);

    get_buffer(pb, tmpbuf, 16);

    if (mxf->aesc)

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

    if (memcmp(tmpbuf, checkv, 16))

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

    size -= 32;

    av_get_packet(pb, pkt, size);

    size -= plaintext_size;

    if (mxf->aesc)

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

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

    pkt->size = orig_size;

    pkt->stream_index = index;

    url_fskip(pb, end - url_ftell(pb));

    return 0;

}

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

{

    KLVPacket klv;

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

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

            return -1;

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

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

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

            if (res < 0) {

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

                return -1;

            }

            return 0;

        }

        if (IS_KLV_KEY(klv.key, mxf_essence_element_key)) {

            int index = mxf_get_stream_index(s, &klv);

            if (index < 0) {

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

                goto skip;

            }

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

                goto skip;

            /* check for 8 channels AES3 element */

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

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

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

                    return -1;

                }

            } else

                av_get_packet(s->pb, pkt, klv.length);

            pkt->stream_index = index;

            pkt->pos = klv.offset;

            return 0;

        } else

        skip:

            url_fskip(s->pb, klv.length);

    }

    return AVERROR(EIO);

}

static int mxf_read_primer_pack(MXFContext *mxf)

{

    ByteIOContext *pb = mxf->fc->pb;

    int item_num = get_be32(pb);

    int item_len = get_be32(pb);

    if (item_len != 18) {

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

        return -1;

    }

    if (item_num > UINT_MAX / item_len)

        return -1;

    mxf->local_tags_count = item_num;

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

    if (!mxf->local_tags)

        return -1;

    get_buffer(pb, mxf->local_tags, item_num*item_len);

    return 0;

}

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

{

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

    if (!mxf->metadata_sets)

        return -1;

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

    mxf->metadata_sets_count++;

    return 0;

}

static int mxf_read_cryptographic_context(MXFCryptoContext *cryptocontext, ByteIOContext *pb, int tag, int size, UID uid)

{

    if (size != 16)

        return -1;

    if (IS_KLV_KEY(uid, mxf_crypto_source_container_ul))

        get_buffer(pb, cryptocontext->source_container_ul, 16);

    return 0;

}

static int mxf_read_content_storage(MXFContext *mxf, ByteIOContext *pb, int tag)

{

    switch (tag) {

    case 0x1901:

        mxf->packages_count = get_be32(pb);

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

            return -1;

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

        if (!mxf->packages_refs)

            return -1;

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

        get_buffer(pb, (uint8_t *)mxf->packages_refs, mxf->packages_count * sizeof(UID));

        break;

    }

    return 0;

}

static int mxf_read_source_clip(MXFStructuralComponent *source_clip, ByteIOContext *pb, int tag)

{

    switch(tag) {

    case 0x0202:

        source_clip->duration = get_be64(pb);

        break;

    case 0x1201:

        source_clip->start_position = get_be64(pb);

        break;

    case 0x1101:

        /* UMID, only get last 16 bytes */

        url_fskip(pb, 16);

        get_buffer(pb, source_clip->source_package_uid, 16);

        break;

    case 0x1102:

        source_clip->source_track_id = get_be32(pb);

        break;

    }

    return 0;

}

static int mxf_read_material_package(MXFPackage *package, ByteIOContext *pb, int tag)

{

    switch(tag) {

    case 0x4403:

        package->tracks_count = get_be32(pb);

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

            return -1;

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

        if (!package->tracks_refs)

            return -1;

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

        get_buffer(pb, (uint8_t *)package->tracks_refs, package->tracks_count * sizeof(UID));

        break;

    }

    return 0;

}

static int mxf_read_track(MXFTrack *track, ByteIOContext *pb, int tag)

{

    switch(tag) {

    case 0x4801:

        track->track_id = get_be32(pb);

        break;

    case 0x4804:

        get_buffer(pb, track->track_number, 4);

        break;

    case 0x4B01:

        track->edit_rate.den = get_be32(pb);

        track->edit_rate.num = get_be32(pb);

        break;

    case 0x4803:

        get_buffer(pb, track->sequence_ref, 16);

        break;

    }

    return 0;

}

static int mxf_read_sequence(MXFSequence *sequence, ByteIOContext *pb, int tag)

{

    switch(tag) {

    case 0x0202:

        sequence->duration = get_be64(pb);

        break;

    case 0x0201:

        get_buffer(pb, sequence->data_definition_ul, 16);

        break;

    case 0x1001:

        sequence->structural_components_count = get_be32(pb);

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

            return -1;

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

        if (!sequence->structural_components_refs)

            return -1;

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

        get_buffer(pb, (uint8_t *)sequence->structural_components_refs, sequence->structural_components_count * sizeof(UID));

        break;

    }

    return 0;

}

static int mxf_read_source_package(MXFPackage *package, ByteIOContext *pb, int tag)

{

    switch(tag) {

    case 0x4403:

        package->tracks_count = get_be32(pb);

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

            return -1;

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

        if (!package->tracks_refs)

            return -1;

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

        get_buffer(pb, (uint8_t *)package->tracks_refs, package->tracks_count * sizeof(UID));

        break;

    case 0x4401:

        /* UMID, only get last 16 bytes */

        url_fskip(pb, 16);

        get_buffer(pb, package->package_uid, 16);

        break;

    case 0x4701:

        get_buffer(pb, package->descriptor_ref, 16);

        break;

    }

    return 0;

}

static void mxf_read_pixel_layout(ByteIOContext *pb, MXFDescriptor *descriptor)

{

    int code;

    do {

        code = get_byte(pb);

        dprintf(NULL, "pixel layout: code 0x%x\n", code);

        switch (code) {

        case 0x52: /* R */

            descriptor->bits_per_sample += get_byte(pb);

            break;

        case 0x47: /* G */

            descriptor->bits_per_sample += get_byte(pb);

            break;

        case 0x42: /* B */

            descriptor->bits_per_sample += get_byte(pb);

            break;

        default:

            get_byte(pb);

        }

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

}

static int mxf_read_generic_descriptor(MXFDescriptor *descriptor, ByteIOContext *pb, int tag, int size, UID uid)

{

    switch(tag) {

    case 0x3F01:

        descriptor->sub_descriptors_count = get_be32(pb);

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

            return -1;

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

        if (!descriptor->sub_descriptors_refs)

            return -1;

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

        get_buffer(pb, (uint8_t *)descriptor->sub_descriptors_refs, descriptor->sub_descriptors_count * sizeof(UID));

        break;

    case 0x3004:

        get_buffer(pb, descriptor->essence_container_ul, 16);

        break;

    case 0x3006:

        descriptor->linked_track_id = get_be32(pb);

        break;

    case 0x3201: /* PictureEssenceCoding */

        get_buffer(pb, descriptor->essence_codec_ul, 16);

        break;

    case 0x3203:

        descriptor->width = get_be32(pb);

        break;

    case 0x3202:

        descriptor->height = get_be32(pb);

        break;

    case 0x320E:

        descriptor->aspect_ratio.num = get_be32(pb);

        descriptor->aspect_ratio.den = get_be32(pb);

        break;

    case 0x3D03:

        descriptor->sample_rate.num = get_be32(pb);

        descriptor->sample_rate.den = get_be32(pb);

        break;

    case 0x3D06: /* SoundEssenceCompression */

        get_buffer(pb, descriptor->essence_codec_ul, 16);

        break;

    case 0x3D07:

        descriptor->channels = get_be32(pb);

        break;

    case 0x3D01:

        descriptor->bits_per_sample = get_be32(pb);

        break;

    case 0x3401:

        mxf_read_pixel_layout(pb, descriptor);

        break;

    default:

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

        if (IS_KLV_KEY(uid, mxf_sony_mpeg4_extradata)) {

            descriptor->extradata = av_malloc(size);

            if (!descriptor->extradata)

                return -1;

            descriptor->extradata_size = size;

            get_buffer(pb, descriptor->extradata, size);

        }

        break;

    }

    return 0;

}

/*

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

 * Returns: boolean

 */

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

{

    int i;

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

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

            return 0;

    }

    return 1;

}

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

{

    while (uls->id != CODEC_ID_NONE) {

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

            break;

        uls++;

    }

    return uls;

}

static enum CodecType mxf_get_codec_type(const MXFDataDefinitionUL *uls, UID *uid)

{

    while (uls->type != CODEC_TYPE_DATA) {

        if(mxf_match_uid(uls->uid, *uid, 16))

            break;

        uls++;

    }

    return uls->type;

}

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

{

    int i;

    if (!strong_ref)

        return NULL;

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

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

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

            return mxf->metadata_sets[i];

        }

    }

    return NULL;

}

static int mxf_parse_structural_metadata(MXFContext *mxf)

{

    MXFPackage *material_package = NULL;

    MXFPackage *temp_package = NULL;

    int i, j, k;

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

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

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

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

        if (material_package) break;

    }

    if (!material_package) {

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

        return -1;

    }

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

        MXFPackage *source_package = NULL;

        MXFTrack *material_track = NULL;

        MXFTrack *source_track = NULL;

        MXFTrack *temp_track = NULL;

        MXFDescriptor *descriptor = NULL;

        MXFStructuralComponent *component = NULL;

        UID *essence_container_ul = NULL;

        const MXFCodecUL *codec_ul = NULL;

        const MXFCodecUL *container_ul = NULL;

        AVStream *st;

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

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

            continue;

        }

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

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

            return -1;

        }

        /* TODO: handle multiple source clips */

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

            /* TODO: handle timecode component */

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

            if (!component)

                continue;

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

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

                if (!temp_package)

                    continue;

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

                    source_package = temp_package;

                    break;

                }

            }

            if (!source_package) {

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

                break;

            }

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

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

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

                    return -1;

                }

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

                    source_track = temp_track;

                    break;

                }

            }

            if (!source_track) {

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

                break;

            }

        }

        if (!source_track)

            continue;

        st = av_new_stream(mxf->fc, source_track->track_id);

        if (!st) {

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

            return -1;

        }

        st->priv_data = source_track;

        st->duration = component->duration;

        if (st->duration == -1)

            st->duration = AV_NOPTS_VALUE;

        st->start_time = component->start_position;

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

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

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

            return -1;

        }

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

        st->codec->codec_type = mxf_get_codec_type(ff_mxf_data_definition_uls, &source_track->sequence->data_definition_ul);

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

        if (source_package->descriptor) {

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

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

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

                    if (!sub_descriptor) {

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

                        continue;

                    }

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

                        descriptor = sub_descriptor;

                        break;

                    }

                }

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

                descriptor = source_package->descriptor;

        }

        if (!descriptor) {

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

            continue;

        }

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

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

        essence_container_ul = &descriptor->essence_container_ul;

        /* HACK: replacing the original key with mxf_encrypted_essence_container

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

        if (IS_KLV_KEY(essence_container_ul, mxf_encrypted_essence_container)) {

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

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

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

                if (metadata->type == CryptoContext) {

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

                    break;

                }

            }

        }

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

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

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

        if (descriptor->extradata) {

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

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

        }

        if (st->codec->codec_type == CODEC_TYPE_VIDEO) {

            container_ul = mxf_get_codec_ul(ff_mxf_essence_container_uls, essence_container_ul);

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

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

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

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

            st->codec->bits_per_sample = descriptor->bits_per_sample; /* Uncompressed */

            st->need_parsing = AVSTREAM_PARSE_HEADERS;

        } else if (st->codec->codec_type == CODEC_TYPE_AUDIO) {

            container_ul = mxf_get_codec_ul(ff_mxf_essence_container_uls, essence_container_ul);

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

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

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

            st->codec->bits_per_sample = descriptor->bits_per_sample;

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

            /* TODO: implement CODEC_ID_RAWAUDIO */

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

                if (descriptor->bits_per_sample == 24)

                    st->codec->codec_id = CODEC_ID_PCM_S24LE;

                else if (descriptor->bits_per_sample == 32)

                    st->codec->codec_id = CODEC_ID_PCM_S32LE;

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

                if (descriptor->bits_per_sample == 24)

                    st->codec->codec_id = CODEC_ID_PCM_S24BE;

                else if (descriptor->bits_per_sample == 32)

                    st->codec->codec_id = CODEC_ID_PCM_S32BE;

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

                st->need_parsing = AVSTREAM_PARSE_FULL;

            }

        }

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

            av_log(mxf->fc, AV_LOG_WARNING, "only frame wrapped mappings are correctly supported\n");

            st->need_parsing = AVSTREAM_PARSE_FULL;

        }

    }

    return 0;

}

static const MXFMetadataReadTableEntry mxf_metadata_read_table[] = {

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

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

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

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

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

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

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

    { { 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 */

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

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

    { { 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 */

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

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

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

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

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

    { { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }, NULL, 0, AnyType },

};

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

{

    ByteIOContext *pb = mxf->fc->pb;

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

    uint64_t klv_end = url_ftell(pb) + klv->length;

    if (!ctx)

        return -1;

    while (url_ftell(pb) + 4 < klv_end) {

        int tag = get_be16(pb);

        int size = get_be16(pb); /* KLV specified by 0x53 */

        uint64_t next = url_ftell(pb) + size;

        UID uid = {0};

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

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

            continue;

        }

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

            int i;

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

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

                if (local_tag == tag) {

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

                    dprintf(mxf->fc, "local tag 0x%04X\n", local_tag);

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

                }

            }

        }

        if (ctx_size && tag == 0x3C0A)

            get_buffer(pb, ctx->uid, 16);

        else if (read_child(ctx, pb, tag, size, uid) < 0)

            return -1;

        url_fseek(pb, next, SEEK_SET);

    }

    if (ctx_size) ctx->type = type;

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

}

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

{

    MXFContext *mxf = s->priv_data;

    KLVPacket klv;

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

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

        return -1;

    }

    url_fseek(s->pb, -14, SEEK_CUR);

    mxf->fc = s;

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

        const MXFMetadataReadTableEntry *metadata;

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

            return -1;

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

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

            IS_KLV_KEY(klv.key, mxf_essence_element_key)) {

            /* FIXME avoid seek */

            url_fseek(s->pb, klv.offset, SEEK_SET);

            break;

        }

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

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

                int (*read)() = klv.key[5] == 0x53 ? mxf_read_local_tags : metadata->read;

                if (read(mxf, &klv, metadata->read, metadata->ctx_size, metadata->type) < 0) {

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

                    return -1;

                }

                break;

            }

        }

        if (!metadata->read)

            url_fskip(s->pb, klv.length);

    }

    return mxf_parse_structural_metadata(mxf);

}

static int mxf_read_close(AVFormatContext *s)

{

    MXFContext *mxf = s->priv_data;

    int i;

    av_freep(&mxf->packages_refs);

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

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

        case MultipleDescriptor:

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

            break;

        case Sequence:

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

            break;

        case SourcePackage:

        case MaterialPackage:

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

            break;

        case Track:

            mxf->metadata_sets[i] = NULL; /* will be freed later */

            break;

        default:

            break;

        }

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

    }

    av_freep(&mxf->metadata_sets);

    av_freep(&mxf->aesc);

    av_freep(&mxf->local_tags);

    return 0;

}

static int mxf_probe(AVProbeData *p) {

    uint8_t *bufp = p->buf;

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

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

        return 0;

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

    end -= sizeof(mxf_header_partition_pack_key);

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

        if (IS_KLV_KEY(bufp, mxf_header_partition_pack_key))

            return AVPROBE_SCORE_MAX;

    }

    return 0;

}

/* rudimentary byte seek */

/* XXX: use MXF Index */

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

{

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

    int64_t seconds;

    if (!s->bit_rate)

        return -1;

    if (sample_time < 0)

        sample_time = 0;

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

    url_fseek(s->pb, (s->bit_rate * seconds) >> 3, SEEK_SET);

    av_update_cur_dts(s, st, sample_time);

    return 0;

}

AVInputFormat mxf_demuxer = {

    "mxf",

    NULL_IF_CONFIG_SMALL("Material eXchange Format"),

    sizeof(MXFContext),

    mxf_probe,

    mxf_read_header,

    mxf_read_packet,

    mxf_read_close,

    mxf_read_seek,

};