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libavformat/mxfdec.c

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00001 /*
00002  * MXF demuxer.
00003  * Copyright (c) 2006 SmartJog S.A., Baptiste Coudurier <baptiste dot coudurier at smartjog dot com>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 /*
00023  * References
00024  * SMPTE 336M KLV Data Encoding Protocol Using Key-Length-Value
00025  * SMPTE 377M MXF File Format Specifications
00026  * SMPTE 378M Operational Pattern 1a
00027  * SMPTE 379M MXF Generic Container
00028  * SMPTE 381M Mapping MPEG Streams into the MXF Generic Container
00029  * SMPTE 382M Mapping AES3 and Broadcast Wave Audio into the MXF Generic Container
00030  * SMPTE 383M Mapping DV-DIF Data to the MXF Generic Container
00031  *
00032  * Principle
00033  * Search for Track numbers which will identify essence element KLV packets.
00034  * Search for SourcePackage which define tracks which contains Track numbers.
00035  * Material Package contains tracks with reference to SourcePackage tracks.
00036  * Search for Descriptors (Picture, Sound) which contains codec info and parameters.
00037  * Assign Descriptors to correct Tracks.
00038  *
00039  * Metadata reading functions read Local Tags, get InstanceUID(0x3C0A) then add MetaDataSet to MXFContext.
00040  * Metadata parsing resolves Strong References to objects.
00041  *
00042  * Simple demuxer, only OP1A supported and some files might not work at all.
00043  * Only tracks with associated descriptors will be decoded. "Highly Desirable" SMPTE 377M D.1
00044  */
00045 
00046 //#define DEBUG
00047 
00048 #include "libavutil/aes.h"
00049 #include "libavcodec/bytestream.h"
00050 #include "avformat.h"
00051 #include "mxf.h"
00052 
00053 typedef struct {
00054     UID uid;
00055     enum MXFMetadataSetType type;
00056     UID source_container_ul;
00057 } MXFCryptoContext;
00058 
00059 typedef struct {
00060     UID uid;
00061     enum MXFMetadataSetType type;
00062     UID source_package_uid;
00063     UID data_definition_ul;
00064     int64_t duration;
00065     int64_t start_position;
00066     int source_track_id;
00067 } MXFStructuralComponent;
00068 
00069 typedef struct {
00070     UID uid;
00071     enum MXFMetadataSetType type;
00072     UID data_definition_ul;
00073     UID *structural_components_refs;
00074     int structural_components_count;
00075     int64_t duration;
00076 } MXFSequence;
00077 
00078 typedef struct {
00079     UID uid;
00080     enum MXFMetadataSetType type;
00081     MXFSequence *sequence; /* mandatory, and only one */
00082     UID sequence_ref;
00083     int track_id;
00084     uint8_t track_number[4];
00085     AVRational edit_rate;
00086 } MXFTrack;
00087 
00088 typedef struct {
00089     UID uid;
00090     enum MXFMetadataSetType type;
00091     UID essence_container_ul;
00092     UID essence_codec_ul;
00093     AVRational sample_rate;
00094     AVRational aspect_ratio;
00095     int width;
00096     int height;
00097     int channels;
00098     int bits_per_sample;
00099     UID *sub_descriptors_refs;
00100     int sub_descriptors_count;
00101     int linked_track_id;
00102     uint8_t *extradata;
00103     int extradata_size;
00104     enum PixelFormat pix_fmt;
00105 } MXFDescriptor;
00106 
00107 typedef struct {
00108     UID uid;
00109     enum MXFMetadataSetType type;
00110 } MXFIndexTableSegment;
00111 
00112 typedef struct {
00113     UID uid;
00114     enum MXFMetadataSetType type;
00115     UID package_uid;
00116     UID *tracks_refs;
00117     int tracks_count;
00118     MXFDescriptor *descriptor; /* only one */
00119     UID descriptor_ref;
00120 } MXFPackage;
00121 
00122 typedef struct {
00123     UID uid;
00124     enum MXFMetadataSetType type;
00125 } MXFMetadataSet;
00126 
00127 typedef struct {
00128     UID *packages_refs;
00129     int packages_count;
00130     MXFMetadataSet **metadata_sets;
00131     int metadata_sets_count;
00132     AVFormatContext *fc;
00133     struct AVAES *aesc;
00134     uint8_t *local_tags;
00135     int local_tags_count;
00136 } MXFContext;
00137 
00138 enum MXFWrappingScheme {
00139     Frame,
00140     Clip,
00141 };
00142 
00143 typedef int MXFMetadataReadFunc(void *arg, AVIOContext *pb, int tag, int size, UID uid);
00144 
00145 typedef struct {
00146     const UID key;
00147     MXFMetadataReadFunc *read;
00148     int ctx_size;
00149     enum MXFMetadataSetType type;
00150 } MXFMetadataReadTableEntry;
00151 
00152 /* partial keys to match */
00153 static const uint8_t mxf_header_partition_pack_key[]       = { 0x06,0x0e,0x2b,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x02 };
00154 static const uint8_t mxf_essence_element_key[]             = { 0x06,0x0e,0x2b,0x34,0x01,0x02,0x01,0x01,0x0d,0x01,0x03,0x01 };
00155 static const uint8_t mxf_klv_key[]                         = { 0x06,0x0e,0x2b,0x34 };
00156 /* complete keys to match */
00157 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 };
00158 static const uint8_t mxf_encrypted_triplet_key[]           = { 0x06,0x0e,0x2b,0x34,0x02,0x04,0x01,0x07,0x0d,0x01,0x03,0x01,0x02,0x7e,0x01,0x00 };
00159 static const uint8_t mxf_encrypted_essence_container[]     = { 0x06,0x0e,0x2b,0x34,0x04,0x01,0x01,0x07,0x0d,0x01,0x03,0x01,0x02,0x0b,0x01,0x00 };
00160 static const uint8_t mxf_sony_mpeg4_extradata[]            = { 0x06,0x0e,0x2b,0x34,0x04,0x01,0x01,0x01,0x0e,0x06,0x06,0x02,0x02,0x01,0x00,0x00 };
00161 
00162 #define IS_KLV_KEY(x, y) (!memcmp(x, y, sizeof(y)))
00163 
00164 static int64_t klv_decode_ber_length(AVIOContext *pb)
00165 {
00166     uint64_t size = avio_r8(pb);
00167     if (size & 0x80) { /* long form */
00168         int bytes_num = size & 0x7f;
00169         /* SMPTE 379M 5.3.4 guarantee that bytes_num must not exceed 8 bytes */
00170         if (bytes_num > 8)
00171             return -1;
00172         size = 0;
00173         while (bytes_num--)
00174             size = size << 8 | avio_r8(pb);
00175     }
00176     return size;
00177 }
00178 
00179 static int mxf_read_sync(AVIOContext *pb, const uint8_t *key, unsigned size)
00180 {
00181     int i, b;
00182     for (i = 0; i < size && !url_feof(pb); i++) {
00183         b = avio_r8(pb);
00184         if (b == key[0])
00185             i = 0;
00186         else if (b != key[i])
00187             i = -1;
00188     }
00189     return i == size;
00190 }
00191 
00192 static int klv_read_packet(KLVPacket *klv, AVIOContext *pb)
00193 {
00194     if (!mxf_read_sync(pb, mxf_klv_key, 4))
00195         return -1;
00196     klv->offset = avio_tell(pb) - 4;
00197     memcpy(klv->key, mxf_klv_key, 4);
00198     avio_read(pb, klv->key + 4, 12);
00199     klv->length = klv_decode_ber_length(pb);
00200     return klv->length == -1 ? -1 : 0;
00201 }
00202 
00203 static int mxf_get_stream_index(AVFormatContext *s, KLVPacket *klv)
00204 {
00205     int i;
00206 
00207     for (i = 0; i < s->nb_streams; i++) {
00208         MXFTrack *track = s->streams[i]->priv_data;
00209         /* SMPTE 379M 7.3 */
00210         if (!memcmp(klv->key + sizeof(mxf_essence_element_key), track->track_number, sizeof(track->track_number)))
00211             return i;
00212     }
00213     /* return 0 if only one stream, for OP Atom files with 0 as track number */
00214     return s->nb_streams == 1 ? 0 : -1;
00215 }
00216 
00217 /* XXX: use AVBitStreamFilter */
00218 static int mxf_get_d10_aes3_packet(AVIOContext *pb, AVStream *st, AVPacket *pkt, int64_t length)
00219 {
00220     const uint8_t *buf_ptr, *end_ptr;
00221     uint8_t *data_ptr;
00222     int i;
00223 
00224     if (length > 61444) /* worst case PAL 1920 samples 8 channels */
00225         return -1;
00226     length = av_get_packet(pb, pkt, length);
00227     if (length < 0)
00228         return length;
00229     data_ptr = pkt->data;
00230     end_ptr = pkt->data + length;
00231     buf_ptr = pkt->data + 4; /* skip SMPTE 331M header */
00232     for (; buf_ptr + st->codec->channels*4 < end_ptr; ) {
00233         for (i = 0; i < st->codec->channels; i++) {
00234             uint32_t sample = bytestream_get_le32(&buf_ptr);
00235             if (st->codec->bits_per_coded_sample == 24)
00236                 bytestream_put_le24(&data_ptr, (sample >> 4) & 0xffffff);
00237             else
00238                 bytestream_put_le16(&data_ptr, (sample >> 12) & 0xffff);
00239         }
00240         buf_ptr += 32 - st->codec->channels*4; // always 8 channels stored SMPTE 331M
00241     }
00242     av_shrink_packet(pkt, data_ptr - pkt->data);
00243     return 0;
00244 }
00245 
00246 static int mxf_decrypt_triplet(AVFormatContext *s, AVPacket *pkt, KLVPacket *klv)
00247 {
00248     static const uint8_t checkv[16] = {0x43, 0x48, 0x55, 0x4b, 0x43, 0x48, 0x55, 0x4b, 0x43, 0x48, 0x55, 0x4b, 0x43, 0x48, 0x55, 0x4b};
00249     MXFContext *mxf = s->priv_data;
00250     AVIOContext *pb = s->pb;
00251     int64_t end = avio_tell(pb) + klv->length;
00252     uint64_t size;
00253     uint64_t orig_size;
00254     uint64_t plaintext_size;
00255     uint8_t ivec[16];
00256     uint8_t tmpbuf[16];
00257     int index;
00258 
00259     if (!mxf->aesc && s->key && s->keylen == 16) {
00260         mxf->aesc = av_malloc(av_aes_size);
00261         if (!mxf->aesc)
00262             return -1;
00263         av_aes_init(mxf->aesc, s->key, 128, 1);
00264     }
00265     // crypto context
00266     avio_skip(pb, klv_decode_ber_length(pb));
00267     // plaintext offset
00268     klv_decode_ber_length(pb);
00269     plaintext_size = avio_rb64(pb);
00270     // source klv key
00271     klv_decode_ber_length(pb);
00272     avio_read(pb, klv->key, 16);
00273     if (!IS_KLV_KEY(klv, mxf_essence_element_key))
00274         return -1;
00275     index = mxf_get_stream_index(s, klv);
00276     if (index < 0)
00277         return -1;
00278     // source size
00279     klv_decode_ber_length(pb);
00280     orig_size = avio_rb64(pb);
00281     if (orig_size < plaintext_size)
00282         return -1;
00283     // enc. code
00284     size = klv_decode_ber_length(pb);
00285     if (size < 32 || size - 32 < orig_size)
00286         return -1;
00287     avio_read(pb, ivec, 16);
00288     avio_read(pb, tmpbuf, 16);
00289     if (mxf->aesc)
00290         av_aes_crypt(mxf->aesc, tmpbuf, tmpbuf, 1, ivec, 1);
00291     if (memcmp(tmpbuf, checkv, 16))
00292         av_log(s, AV_LOG_ERROR, "probably incorrect decryption key\n");
00293     size -= 32;
00294     size = av_get_packet(pb, pkt, size);
00295     if (size < 0)
00296         return size;
00297     else if (size < plaintext_size)
00298         return AVERROR_INVALIDDATA;
00299     size -= plaintext_size;
00300     if (mxf->aesc)
00301         av_aes_crypt(mxf->aesc, &pkt->data[plaintext_size],
00302                      &pkt->data[plaintext_size], size >> 4, ivec, 1);
00303     av_shrink_packet(pkt, orig_size);
00304     pkt->stream_index = index;
00305     avio_skip(pb, end - avio_tell(pb));
00306     return 0;
00307 }
00308 
00309 static int mxf_read_packet(AVFormatContext *s, AVPacket *pkt)
00310 {
00311     KLVPacket klv;
00312 
00313     while (!url_feof(s->pb)) {
00314         if (klv_read_packet(&klv, s->pb) < 0)
00315             return -1;
00316         PRINT_KEY(s, "read packet", klv.key);
00317         av_dlog(s, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset);
00318         if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key)) {
00319             int res = mxf_decrypt_triplet(s, pkt, &klv);
00320             if (res < 0) {
00321                 av_log(s, AV_LOG_ERROR, "invalid encoded triplet\n");
00322                 return -1;
00323             }
00324             return 0;
00325         }
00326         if (IS_KLV_KEY(klv.key, mxf_essence_element_key)) {
00327             int index = mxf_get_stream_index(s, &klv);
00328             if (index < 0) {
00329                 av_log(s, AV_LOG_ERROR, "error getting stream index %d\n", AV_RB32(klv.key+12));
00330                 goto skip;
00331             }
00332             if (s->streams[index]->discard == AVDISCARD_ALL)
00333                 goto skip;
00334             /* check for 8 channels AES3 element */
00335             if (klv.key[12] == 0x06 && klv.key[13] == 0x01 && klv.key[14] == 0x10) {
00336                 if (mxf_get_d10_aes3_packet(s->pb, s->streams[index], pkt, klv.length) < 0) {
00337                     av_log(s, AV_LOG_ERROR, "error reading D-10 aes3 frame\n");
00338                     return -1;
00339                 }
00340             } else {
00341                 int ret = av_get_packet(s->pb, pkt, klv.length);
00342                 if (ret < 0)
00343                     return ret;
00344             }
00345             pkt->stream_index = index;
00346             pkt->pos = klv.offset;
00347             return 0;
00348         } else
00349         skip:
00350             avio_skip(s->pb, klv.length);
00351     }
00352     return AVERROR_EOF;
00353 }
00354 
00355 static int mxf_read_primer_pack(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00356 {
00357     MXFContext *mxf = arg;
00358     int item_num = avio_rb32(pb);
00359     int item_len = avio_rb32(pb);
00360 
00361     if (item_len != 18) {
00362         av_log(mxf->fc, AV_LOG_ERROR, "unsupported primer pack item length\n");
00363         return -1;
00364     }
00365     if (item_num > UINT_MAX / item_len)
00366         return -1;
00367     mxf->local_tags_count = item_num;
00368     mxf->local_tags = av_malloc(item_num*item_len);
00369     if (!mxf->local_tags)
00370         return -1;
00371     avio_read(pb, mxf->local_tags, item_num*item_len);
00372     return 0;
00373 }
00374 
00375 static int mxf_add_metadata_set(MXFContext *mxf, void *metadata_set)
00376 {
00377     if (mxf->metadata_sets_count+1 >= UINT_MAX / sizeof(*mxf->metadata_sets))
00378         return AVERROR(ENOMEM);
00379     mxf->metadata_sets = av_realloc(mxf->metadata_sets, (mxf->metadata_sets_count + 1) * sizeof(*mxf->metadata_sets));
00380     if (!mxf->metadata_sets)
00381         return -1;
00382     mxf->metadata_sets[mxf->metadata_sets_count] = metadata_set;
00383     mxf->metadata_sets_count++;
00384     return 0;
00385 }
00386 
00387 static int mxf_read_cryptographic_context(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00388 {
00389     MXFCryptoContext *cryptocontext = arg;
00390     if (size != 16)
00391         return -1;
00392     if (IS_KLV_KEY(uid, mxf_crypto_source_container_ul))
00393         avio_read(pb, cryptocontext->source_container_ul, 16);
00394     return 0;
00395 }
00396 
00397 static int mxf_read_content_storage(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00398 {
00399     MXFContext *mxf = arg;
00400     switch (tag) {
00401     case 0x1901:
00402         mxf->packages_count = avio_rb32(pb);
00403         if (mxf->packages_count >= UINT_MAX / sizeof(UID))
00404             return -1;
00405         mxf->packages_refs = av_malloc(mxf->packages_count * sizeof(UID));
00406         if (!mxf->packages_refs)
00407             return -1;
00408         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */
00409         avio_read(pb, (uint8_t *)mxf->packages_refs, mxf->packages_count * sizeof(UID));
00410         break;
00411     }
00412     return 0;
00413 }
00414 
00415 static int mxf_read_source_clip(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00416 {
00417     MXFStructuralComponent *source_clip = arg;
00418     switch(tag) {
00419     case 0x0202:
00420         source_clip->duration = avio_rb64(pb);
00421         break;
00422     case 0x1201:
00423         source_clip->start_position = avio_rb64(pb);
00424         break;
00425     case 0x1101:
00426         /* UMID, only get last 16 bytes */
00427         avio_skip(pb, 16);
00428         avio_read(pb, source_clip->source_package_uid, 16);
00429         break;
00430     case 0x1102:
00431         source_clip->source_track_id = avio_rb32(pb);
00432         break;
00433     }
00434     return 0;
00435 }
00436 
00437 static int mxf_read_material_package(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00438 {
00439     MXFPackage *package = arg;
00440     switch(tag) {
00441     case 0x4403:
00442         package->tracks_count = avio_rb32(pb);
00443         if (package->tracks_count >= UINT_MAX / sizeof(UID))
00444             return -1;
00445         package->tracks_refs = av_malloc(package->tracks_count * sizeof(UID));
00446         if (!package->tracks_refs)
00447             return -1;
00448         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */
00449         avio_read(pb, (uint8_t *)package->tracks_refs, package->tracks_count * sizeof(UID));
00450         break;
00451     }
00452     return 0;
00453 }
00454 
00455 static int mxf_read_track(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00456 {
00457     MXFTrack *track = arg;
00458     switch(tag) {
00459     case 0x4801:
00460         track->track_id = avio_rb32(pb);
00461         break;
00462     case 0x4804:
00463         avio_read(pb, track->track_number, 4);
00464         break;
00465     case 0x4B01:
00466         track->edit_rate.den = avio_rb32(pb);
00467         track->edit_rate.num = avio_rb32(pb);
00468         break;
00469     case 0x4803:
00470         avio_read(pb, track->sequence_ref, 16);
00471         break;
00472     }
00473     return 0;
00474 }
00475 
00476 static int mxf_read_sequence(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00477 {
00478     MXFSequence *sequence = arg;
00479     switch(tag) {
00480     case 0x0202:
00481         sequence->duration = avio_rb64(pb);
00482         break;
00483     case 0x0201:
00484         avio_read(pb, sequence->data_definition_ul, 16);
00485         break;
00486     case 0x1001:
00487         sequence->structural_components_count = avio_rb32(pb);
00488         if (sequence->structural_components_count >= UINT_MAX / sizeof(UID))
00489             return -1;
00490         sequence->structural_components_refs = av_malloc(sequence->structural_components_count * sizeof(UID));
00491         if (!sequence->structural_components_refs)
00492             return -1;
00493         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */
00494         avio_read(pb, (uint8_t *)sequence->structural_components_refs, sequence->structural_components_count * sizeof(UID));
00495         break;
00496     }
00497     return 0;
00498 }
00499 
00500 static int mxf_read_source_package(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00501 {
00502     MXFPackage *package = arg;
00503     switch(tag) {
00504     case 0x4403:
00505         package->tracks_count = avio_rb32(pb);
00506         if (package->tracks_count >= UINT_MAX / sizeof(UID))
00507             return -1;
00508         package->tracks_refs = av_malloc(package->tracks_count * sizeof(UID));
00509         if (!package->tracks_refs)
00510             return -1;
00511         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */
00512         avio_read(pb, (uint8_t *)package->tracks_refs, package->tracks_count * sizeof(UID));
00513         break;
00514     case 0x4401:
00515         /* UMID, only get last 16 bytes */
00516         avio_skip(pb, 16);
00517         avio_read(pb, package->package_uid, 16);
00518         break;
00519     case 0x4701:
00520         avio_read(pb, package->descriptor_ref, 16);
00521         break;
00522     }
00523     return 0;
00524 }
00525 
00526 static int mxf_read_index_table_segment(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00527 {
00528     switch(tag) {
00529     case 0x3F05: av_dlog(NULL, "EditUnitByteCount %d\n", avio_rb32(pb)); break;
00530     case 0x3F06: av_dlog(NULL, "IndexSID %d\n", avio_rb32(pb)); break;
00531     case 0x3F07: av_dlog(NULL, "BodySID %d\n", avio_rb32(pb)); break;
00532     case 0x3F0B: av_dlog(NULL, "IndexEditRate %d/%d\n", avio_rb32(pb), avio_rb32(pb)); break;
00533     case 0x3F0C: av_dlog(NULL, "IndexStartPosition %"PRIu64"\n", avio_rb64(pb)); break;
00534     case 0x3F0D: av_dlog(NULL, "IndexDuration %"PRIu64"\n", avio_rb64(pb)); break;
00535     }
00536     return 0;
00537 }
00538 
00539 static void mxf_read_pixel_layout(AVIOContext *pb, MXFDescriptor *descriptor)
00540 {
00541     int code, value, ofs = 0;
00542     char layout[16] = {0};
00543 
00544     do {
00545         code = avio_r8(pb);
00546         value = avio_r8(pb);
00547         av_dlog(NULL, "pixel layout: code %#x\n", code);
00548 
00549         if (ofs < 16) {
00550             layout[ofs++] = code;
00551             layout[ofs++] = value;
00552         }
00553     } while (code != 0); /* SMPTE 377M E.2.46 */
00554 
00555     ff_mxf_decode_pixel_layout(layout, &descriptor->pix_fmt);
00556 }
00557 
00558 static int mxf_read_generic_descriptor(void *arg, AVIOContext *pb, int tag, int size, UID uid)
00559 {
00560     MXFDescriptor *descriptor = arg;
00561     switch(tag) {
00562     case 0x3F01:
00563         descriptor->sub_descriptors_count = avio_rb32(pb);
00564         if (descriptor->sub_descriptors_count >= UINT_MAX / sizeof(UID))
00565             return -1;
00566         descriptor->sub_descriptors_refs = av_malloc(descriptor->sub_descriptors_count * sizeof(UID));
00567         if (!descriptor->sub_descriptors_refs)
00568             return -1;
00569         avio_skip(pb, 4); /* useless size of objects, always 16 according to specs */
00570         avio_read(pb, (uint8_t *)descriptor->sub_descriptors_refs, descriptor->sub_descriptors_count * sizeof(UID));
00571         break;
00572     case 0x3004:
00573         avio_read(pb, descriptor->essence_container_ul, 16);
00574         break;
00575     case 0x3006:
00576         descriptor->linked_track_id = avio_rb32(pb);
00577         break;
00578     case 0x3201: /* PictureEssenceCoding */
00579         avio_read(pb, descriptor->essence_codec_ul, 16);
00580         break;
00581     case 0x3203:
00582         descriptor->width = avio_rb32(pb);
00583         break;
00584     case 0x3202:
00585         descriptor->height = avio_rb32(pb);
00586         break;
00587     case 0x320E:
00588         descriptor->aspect_ratio.num = avio_rb32(pb);
00589         descriptor->aspect_ratio.den = avio_rb32(pb);
00590         break;
00591     case 0x3D03:
00592         descriptor->sample_rate.num = avio_rb32(pb);
00593         descriptor->sample_rate.den = avio_rb32(pb);
00594         break;
00595     case 0x3D06: /* SoundEssenceCompression */
00596         avio_read(pb, descriptor->essence_codec_ul, 16);
00597         break;
00598     case 0x3D07:
00599         descriptor->channels = avio_rb32(pb);
00600         break;
00601     case 0x3D01:
00602         descriptor->bits_per_sample = avio_rb32(pb);
00603         break;
00604     case 0x3401:
00605         mxf_read_pixel_layout(pb, descriptor);
00606         break;
00607     default:
00608         /* Private uid used by SONY C0023S01.mxf */
00609         if (IS_KLV_KEY(uid, mxf_sony_mpeg4_extradata)) {
00610             descriptor->extradata = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
00611             if (!descriptor->extradata)
00612                 return -1;
00613             descriptor->extradata_size = size;
00614             avio_read(pb, descriptor->extradata, size);
00615         }
00616         break;
00617     }
00618     return 0;
00619 }
00620 
00621 /*
00622  * Match an uid independently of the version byte and up to len common bytes
00623  * Returns: boolean
00624  */
00625 static int mxf_match_uid(const UID key, const UID uid, int len)
00626 {
00627     int i;
00628     for (i = 0; i < len; i++) {
00629         if (i != 7 && key[i] != uid[i])
00630             return 0;
00631     }
00632     return 1;
00633 }
00634 
00635 static const MXFCodecUL *mxf_get_codec_ul(const MXFCodecUL *uls, UID *uid)
00636 {
00637     while (uls->uid[0]) {
00638         if(mxf_match_uid(uls->uid, *uid, uls->matching_len))
00639             break;
00640         uls++;
00641     }
00642     return uls;
00643 }
00644 
00645 static void *mxf_resolve_strong_ref(MXFContext *mxf, UID *strong_ref, enum MXFMetadataSetType type)
00646 {
00647     int i;
00648 
00649     if (!strong_ref)
00650         return NULL;
00651     for (i = 0; i < mxf->metadata_sets_count; i++) {
00652         if (!memcmp(*strong_ref, mxf->metadata_sets[i]->uid, 16) &&
00653             (type == AnyType || mxf->metadata_sets[i]->type == type)) {
00654             return mxf->metadata_sets[i];
00655         }
00656     }
00657     return NULL;
00658 }
00659 
00660 static const MXFCodecUL mxf_essence_container_uls[] = {
00661     // video essence container uls
00662     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x02,0x0D,0x01,0x03,0x01,0x02,0x04,0x60,0x01 }, 14, CODEC_ID_MPEG2VIDEO }, /* MPEG-ES Frame wrapped */
00663     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x0D,0x01,0x03,0x01,0x02,0x02,0x41,0x01 }, 14,    CODEC_ID_DVVIDEO }, /* DV 625 25mbps */
00664     // sound essence container uls
00665     { { 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x01,0x0D,0x01,0x03,0x01,0x02,0x06,0x01,0x00 }, 14, CODEC_ID_PCM_S16LE }, /* BWF Frame wrapped */
00666     { { 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 */
00667     { { 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 */
00668     { { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 },  0,      CODEC_ID_NONE },
00669 };
00670 
00671 static int mxf_parse_structural_metadata(MXFContext *mxf)
00672 {
00673     MXFPackage *material_package = NULL;
00674     MXFPackage *temp_package = NULL;
00675     int i, j, k;
00676 
00677     av_dlog(mxf->fc, "metadata sets count %d\n", mxf->metadata_sets_count);
00678     /* TODO: handle multiple material packages (OP3x) */
00679     for (i = 0; i < mxf->packages_count; i++) {
00680         material_package = mxf_resolve_strong_ref(mxf, &mxf->packages_refs[i], MaterialPackage);
00681         if (material_package) break;
00682     }
00683     if (!material_package) {
00684         av_log(mxf->fc, AV_LOG_ERROR, "no material package found\n");
00685         return -1;
00686     }
00687 
00688     for (i = 0; i < material_package->tracks_count; i++) {
00689         MXFPackage *source_package = NULL;
00690         MXFTrack *material_track = NULL;
00691         MXFTrack *source_track = NULL;
00692         MXFTrack *temp_track = NULL;
00693         MXFDescriptor *descriptor = NULL;
00694         MXFStructuralComponent *component = NULL;
00695         UID *essence_container_ul = NULL;
00696         const MXFCodecUL *codec_ul = NULL;
00697         const MXFCodecUL *container_ul = NULL;
00698         AVStream *st;
00699 
00700         if (!(material_track = mxf_resolve_strong_ref(mxf, &material_package->tracks_refs[i], Track))) {
00701             av_log(mxf->fc, AV_LOG_ERROR, "could not resolve material track strong ref\n");
00702             continue;
00703         }
00704 
00705         if (!(material_track->sequence = mxf_resolve_strong_ref(mxf, &material_track->sequence_ref, Sequence))) {
00706             av_log(mxf->fc, AV_LOG_ERROR, "could not resolve material track sequence strong ref\n");
00707             continue;
00708         }
00709 
00710         /* TODO: handle multiple source clips */
00711         for (j = 0; j < material_track->sequence->structural_components_count; j++) {
00712             /* TODO: handle timecode component */
00713             component = mxf_resolve_strong_ref(mxf, &material_track->sequence->structural_components_refs[j], SourceClip);
00714             if (!component)
00715                 continue;
00716 
00717             for (k = 0; k < mxf->packages_count; k++) {
00718                 temp_package = mxf_resolve_strong_ref(mxf, &mxf->packages_refs[k], SourcePackage);
00719                 if (!temp_package)
00720                     continue;
00721                 if (!memcmp(temp_package->package_uid, component->source_package_uid, 16)) {
00722                     source_package = temp_package;
00723                     break;
00724                 }
00725             }
00726             if (!source_package) {
00727                 av_log(mxf->fc, AV_LOG_ERROR, "material track %d: no corresponding source package found\n", material_track->track_id);
00728                 break;
00729             }
00730             for (k = 0; k < source_package->tracks_count; k++) {
00731                 if (!(temp_track = mxf_resolve_strong_ref(mxf, &source_package->tracks_refs[k], Track))) {
00732                     av_log(mxf->fc, AV_LOG_ERROR, "could not resolve source track strong ref\n");
00733                     return -1;
00734                 }
00735                 if (temp_track->track_id == component->source_track_id) {
00736                     source_track = temp_track;
00737                     break;
00738                 }
00739             }
00740             if (!source_track) {
00741                 av_log(mxf->fc, AV_LOG_ERROR, "material track %d: no corresponding source track found\n", material_track->track_id);
00742                 break;
00743             }
00744         }
00745         if (!source_track)
00746             continue;
00747 
00748         st = av_new_stream(mxf->fc, source_track->track_id);
00749         if (!st) {
00750             av_log(mxf->fc, AV_LOG_ERROR, "could not allocate stream\n");
00751             return -1;
00752         }
00753         st->priv_data = source_track;
00754         st->duration = component->duration;
00755         if (st->duration == -1)
00756             st->duration = AV_NOPTS_VALUE;
00757         st->start_time = component->start_position;
00758         av_set_pts_info(st, 64, material_track->edit_rate.num, material_track->edit_rate.den);
00759 
00760         if (!(source_track->sequence = mxf_resolve_strong_ref(mxf, &source_track->sequence_ref, Sequence))) {
00761             av_log(mxf->fc, AV_LOG_ERROR, "could not resolve source track sequence strong ref\n");
00762             return -1;
00763         }
00764 
00765         PRINT_KEY(mxf->fc, "data definition   ul", source_track->sequence->data_definition_ul);
00766         codec_ul = mxf_get_codec_ul(ff_mxf_data_definition_uls, &source_track->sequence->data_definition_ul);
00767         st->codec->codec_type = codec_ul->id;
00768 
00769         source_package->descriptor = mxf_resolve_strong_ref(mxf, &source_package->descriptor_ref, AnyType);
00770         if (source_package->descriptor) {
00771             if (source_package->descriptor->type == MultipleDescriptor) {
00772                 for (j = 0; j < source_package->descriptor->sub_descriptors_count; j++) {
00773                     MXFDescriptor *sub_descriptor = mxf_resolve_strong_ref(mxf, &source_package->descriptor->sub_descriptors_refs[j], Descriptor);
00774 
00775                     if (!sub_descriptor) {
00776                         av_log(mxf->fc, AV_LOG_ERROR, "could not resolve sub descriptor strong ref\n");
00777                         continue;
00778                     }
00779                     if (sub_descriptor->linked_track_id == source_track->track_id) {
00780                         descriptor = sub_descriptor;
00781                         break;
00782                     }
00783                 }
00784             } else if (source_package->descriptor->type == Descriptor)
00785                 descriptor = source_package->descriptor;
00786         }
00787         if (!descriptor) {
00788             av_log(mxf->fc, AV_LOG_INFO, "source track %d: stream %d, no descriptor found\n", source_track->track_id, st->index);
00789             continue;
00790         }
00791         PRINT_KEY(mxf->fc, "essence codec     ul", descriptor->essence_codec_ul);
00792         PRINT_KEY(mxf->fc, "essence container ul", descriptor->essence_container_ul);
00793         essence_container_ul = &descriptor->essence_container_ul;
00794         /* HACK: replacing the original key with mxf_encrypted_essence_container
00795          * is not allowed according to s429-6, try to find correct information anyway */
00796         if (IS_KLV_KEY(essence_container_ul, mxf_encrypted_essence_container)) {
00797             av_log(mxf->fc, AV_LOG_INFO, "broken encrypted mxf file\n");
00798             for (k = 0; k < mxf->metadata_sets_count; k++) {
00799                 MXFMetadataSet *metadata = mxf->metadata_sets[k];
00800                 if (metadata->type == CryptoContext) {
00801                     essence_container_ul = &((MXFCryptoContext *)metadata)->source_container_ul;
00802                     break;
00803                 }
00804             }
00805         }
00806         /* TODO: drop PictureEssenceCoding and SoundEssenceCompression, only check EssenceContainer */
00807         codec_ul = mxf_get_codec_ul(ff_mxf_codec_uls, &descriptor->essence_codec_ul);
00808         st->codec->codec_id = codec_ul->id;
00809         if (descriptor->extradata) {
00810             st->codec->extradata = descriptor->extradata;
00811             st->codec->extradata_size = descriptor->extradata_size;
00812         }
00813         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
00814             container_ul = mxf_get_codec_ul(mxf_essence_container_uls, essence_container_ul);
00815             if (st->codec->codec_id == CODEC_ID_NONE)
00816                 st->codec->codec_id = container_ul->id;
00817             st->codec->width = descriptor->width;
00818             st->codec->height = descriptor->height;
00819             if (st->codec->codec_id == CODEC_ID_RAWVIDEO)
00820                 st->codec->pix_fmt = descriptor->pix_fmt;
00821             st->need_parsing = AVSTREAM_PARSE_HEADERS;
00822         } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
00823             container_ul = mxf_get_codec_ul(mxf_essence_container_uls, essence_container_ul);
00824             if (st->codec->codec_id == CODEC_ID_NONE)
00825                 st->codec->codec_id = container_ul->id;
00826             st->codec->channels = descriptor->channels;
00827             st->codec->bits_per_coded_sample = descriptor->bits_per_sample;
00828             st->codec->sample_rate = descriptor->sample_rate.num / descriptor->sample_rate.den;
00829             /* TODO: implement CODEC_ID_RAWAUDIO */
00830             if (st->codec->codec_id == CODEC_ID_PCM_S16LE) {
00831                 if (descriptor->bits_per_sample == 24)
00832                     st->codec->codec_id = CODEC_ID_PCM_S24LE;
00833                 else if (descriptor->bits_per_sample == 32)
00834                     st->codec->codec_id = CODEC_ID_PCM_S32LE;
00835             } else if (st->codec->codec_id == CODEC_ID_PCM_S16BE) {
00836                 if (descriptor->bits_per_sample == 24)
00837                     st->codec->codec_id = CODEC_ID_PCM_S24BE;
00838                 else if (descriptor->bits_per_sample == 32)
00839                     st->codec->codec_id = CODEC_ID_PCM_S32BE;
00840             } else if (st->codec->codec_id == CODEC_ID_MP2) {
00841                 st->need_parsing = AVSTREAM_PARSE_FULL;
00842             }
00843         }
00844         if (st->codec->codec_type != AVMEDIA_TYPE_DATA && (*essence_container_ul)[15] > 0x01) {
00845             av_log(mxf->fc, AV_LOG_WARNING, "only frame wrapped mappings are correctly supported\n");
00846             st->need_parsing = AVSTREAM_PARSE_FULL;
00847         }
00848     }
00849     return 0;
00850 }
00851 
00852 static const MXFMetadataReadTableEntry mxf_metadata_read_table[] = {
00853     { { 0x06,0x0E,0x2B,0x34,0x02,0x05,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x05,0x01,0x00 }, mxf_read_primer_pack },
00854     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x18,0x00 }, mxf_read_content_storage, 0, AnyType },
00855     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x37,0x00 }, mxf_read_source_package, sizeof(MXFPackage), SourcePackage },
00856     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x36,0x00 }, mxf_read_material_package, sizeof(MXFPackage), MaterialPackage },
00857     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x0F,0x00 }, mxf_read_sequence, sizeof(MXFSequence), Sequence },
00858     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x11,0x00 }, mxf_read_source_clip, sizeof(MXFStructuralComponent), SourceClip },
00859     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x44,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), MultipleDescriptor },
00860     { { 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 */
00861     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x28,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* CDCI */
00862     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x29,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* RGBA */
00863     { { 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 */
00864     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x48,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* Wave */
00865     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x47,0x00 }, mxf_read_generic_descriptor, sizeof(MXFDescriptor), Descriptor }, /* AES3 */
00866     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x3A,0x00 }, mxf_read_track, sizeof(MXFTrack), Track }, /* Static Track */
00867     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x01,0x01,0x01,0x01,0x3B,0x00 }, mxf_read_track, sizeof(MXFTrack), Track }, /* Generic Track */
00868     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x04,0x01,0x02,0x02,0x00,0x00 }, mxf_read_cryptographic_context, sizeof(MXFCryptoContext), CryptoContext },
00869     { { 0x06,0x0E,0x2B,0x34,0x02,0x53,0x01,0x01,0x0d,0x01,0x02,0x01,0x01,0x10,0x01,0x00 }, mxf_read_index_table_segment, sizeof(MXFIndexTableSegment), IndexTableSegment },
00870     { { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }, NULL, 0, AnyType },
00871 };
00872 
00873 static int mxf_read_local_tags(MXFContext *mxf, KLVPacket *klv, MXFMetadataReadFunc *read_child, int ctx_size, enum MXFMetadataSetType type)
00874 {
00875     AVIOContext *pb = mxf->fc->pb;
00876     MXFMetadataSet *ctx = ctx_size ? av_mallocz(ctx_size) : mxf;
00877     uint64_t klv_end = avio_tell(pb) + klv->length;
00878 
00879     if (!ctx)
00880         return -1;
00881     while (avio_tell(pb) + 4 < klv_end) {
00882         int tag = avio_rb16(pb);
00883         int size = avio_rb16(pb); /* KLV specified by 0x53 */
00884         uint64_t next = avio_tell(pb) + size;
00885         UID uid = {0};
00886 
00887         av_dlog(mxf->fc, "local tag %#04x size %d\n", tag, size);
00888         if (!size) { /* ignore empty tag, needed for some files with empty UMID tag */
00889             av_log(mxf->fc, AV_LOG_ERROR, "local tag %#04x with 0 size\n", tag);
00890             continue;
00891         }
00892         if (tag > 0x7FFF) { /* dynamic tag */
00893             int i;
00894             for (i = 0; i < mxf->local_tags_count; i++) {
00895                 int local_tag = AV_RB16(mxf->local_tags+i*18);
00896                 if (local_tag == tag) {
00897                     memcpy(uid, mxf->local_tags+i*18+2, 16);
00898                     av_dlog(mxf->fc, "local tag %#04x\n", local_tag);
00899                     PRINT_KEY(mxf->fc, "uid", uid);
00900                 }
00901             }
00902         }
00903         if (ctx_size && tag == 0x3C0A)
00904             avio_read(pb, ctx->uid, 16);
00905         else if (read_child(ctx, pb, tag, size, uid) < 0)
00906             return -1;
00907 
00908         avio_seek(pb, next, SEEK_SET);
00909     }
00910     if (ctx_size) ctx->type = type;
00911     return ctx_size ? mxf_add_metadata_set(mxf, ctx) : 0;
00912 }
00913 
00914 static int mxf_read_header(AVFormatContext *s, AVFormatParameters *ap)
00915 {
00916     MXFContext *mxf = s->priv_data;
00917     KLVPacket klv;
00918 
00919     if (!mxf_read_sync(s->pb, mxf_header_partition_pack_key, 14)) {
00920         av_log(s, AV_LOG_ERROR, "could not find header partition pack key\n");
00921         return -1;
00922     }
00923     avio_seek(s->pb, -14, SEEK_CUR);
00924     mxf->fc = s;
00925     while (!url_feof(s->pb)) {
00926         const MXFMetadataReadTableEntry *metadata;
00927 
00928         if (klv_read_packet(&klv, s->pb) < 0)
00929             return -1;
00930         PRINT_KEY(s, "read header", klv.key);
00931         av_dlog(s, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset);
00932         if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key) ||
00933             IS_KLV_KEY(klv.key, mxf_essence_element_key)) {
00934             /* FIXME avoid seek */
00935             avio_seek(s->pb, klv.offset, SEEK_SET);
00936             break;
00937         }
00938 
00939         for (metadata = mxf_metadata_read_table; metadata->read; metadata++) {
00940             if (IS_KLV_KEY(klv.key, metadata->key)) {
00941                 int res;
00942                 if (klv.key[5] == 0x53) {
00943                     res = mxf_read_local_tags(mxf, &klv, metadata->read, metadata->ctx_size, metadata->type);
00944                 } else
00945                     res = metadata->read(mxf, s->pb, 0, 0, NULL);
00946                 if (res < 0) {
00947                     av_log(s, AV_LOG_ERROR, "error reading header metadata\n");
00948                     return -1;
00949                 }
00950                 break;
00951             }
00952         }
00953         if (!metadata->read)
00954             avio_skip(s->pb, klv.length);
00955     }
00956     return mxf_parse_structural_metadata(mxf);
00957 }
00958 
00959 static int mxf_read_close(AVFormatContext *s)
00960 {
00961     MXFContext *mxf = s->priv_data;
00962     int i;
00963 
00964     av_freep(&mxf->packages_refs);
00965 
00966     for (i = 0; i < s->nb_streams; i++)
00967         s->streams[i]->priv_data = NULL;
00968 
00969     for (i = 0; i < mxf->metadata_sets_count; i++) {
00970         switch (mxf->metadata_sets[i]->type) {
00971         case MultipleDescriptor:
00972             av_freep(&((MXFDescriptor *)mxf->metadata_sets[i])->sub_descriptors_refs);
00973             break;
00974         case Sequence:
00975             av_freep(&((MXFSequence *)mxf->metadata_sets[i])->structural_components_refs);
00976             break;
00977         case SourcePackage:
00978         case MaterialPackage:
00979             av_freep(&((MXFPackage *)mxf->metadata_sets[i])->tracks_refs);
00980             break;
00981         default:
00982             break;
00983         }
00984         av_freep(&mxf->metadata_sets[i]);
00985     }
00986     av_freep(&mxf->metadata_sets);
00987     av_freep(&mxf->aesc);
00988     av_freep(&mxf->local_tags);
00989     return 0;
00990 }
00991 
00992 static int mxf_probe(AVProbeData *p) {
00993     uint8_t *bufp = p->buf;
00994     uint8_t *end = p->buf + p->buf_size;
00995 
00996     if (p->buf_size < sizeof(mxf_header_partition_pack_key))
00997         return 0;
00998 
00999     /* Must skip Run-In Sequence and search for MXF header partition pack key SMPTE 377M 5.5 */
01000     end -= sizeof(mxf_header_partition_pack_key);
01001     for (; bufp < end; bufp++) {
01002         if (IS_KLV_KEY(bufp, mxf_header_partition_pack_key))
01003             return AVPROBE_SCORE_MAX;
01004     }
01005     return 0;
01006 }
01007 
01008 /* rudimentary byte seek */
01009 /* XXX: use MXF Index */
01010 static int mxf_read_seek(AVFormatContext *s, int stream_index, int64_t sample_time, int flags)
01011 {
01012     AVStream *st = s->streams[stream_index];
01013     int64_t seconds;
01014 
01015     if (!s->bit_rate)
01016         return -1;
01017     if (sample_time < 0)
01018         sample_time = 0;
01019     seconds = av_rescale(sample_time, st->time_base.num, st->time_base.den);
01020     avio_seek(s->pb, (s->bit_rate * seconds) >> 3, SEEK_SET);
01021     av_update_cur_dts(s, st, sample_time);
01022     return 0;
01023 }
01024 
01025 AVInputFormat ff_mxf_demuxer = {
01026     "mxf",
01027     NULL_IF_CONFIG_SMALL("Material eXchange Format"),
01028     sizeof(MXFContext),
01029     mxf_probe,
01030     mxf_read_header,
01031     mxf_read_packet,
01032     mxf_read_close,
01033     mxf_read_seek,
01034 };

Generated on Wed Apr 11 2012 07:31:36 for FFmpeg by  doxygen 1.7.1