static int mxf_read_header(AVFormatContext *s, AVFormatParameters *ap) { MXFContext *mxf = s->priv_data; KLVPacket klv; int64_t essence_offset = 0; mxf->last_forward_tell = INT64_MAX; 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 AVERROR_INVALIDDATA; } avio_seek(s->pb, -14, SEEK_CUR); mxf->fc = s; mxf->run_in = avio_tell(s->pb); while (!s->pb->eof_reached) { const MXFMetadataReadTableEntry *metadata; if (klv_read_packet(&klv, s->pb) < 0) { /* EOF - seek to previous partition or stop */ if(mxf_parse_handle_partition_or_eof(mxf) <= 0) break; else continue; } PRINT_KEY(s, "read header", klv.key); av_dlog(s, "size %"PRIu64" offset %#"PRIx64"\n", klv.length, klv.offset); if (IS_KLV_KEY(klv.key, mxf_encrypted_triplet_key) || IS_KLV_KEY(klv.key, mxf_essence_element_key) || IS_KLV_KEY(klv.key, mxf_avid_essence_element_key) || IS_KLV_KEY(klv.key, mxf_system_item_key)) { if (!mxf->current_partition->essence_offset) { compute_partition_essence_offset(s, mxf, &klv); } if (!essence_offset) essence_offset = klv.offset; /* seek to footer, previous partition or stop */ if (mxf_parse_handle_essence(mxf) <= 0) break; continue; } else if (!memcmp(klv.key, mxf_header_partition_pack_key, 13) && klv.key[13] >= 2 && klv.key[13] <= 4 && mxf->current_partition) { /* next partition pack - keep going, seek to previous partition or stop */ if(mxf_parse_handle_partition_or_eof(mxf) <= 0) break; } for (metadata = mxf_metadata_read_table; metadata->read; metadata++) { if (IS_KLV_KEY(klv.key, metadata->key)) { int res; if (klv.key[5] == 0x53) { res = mxf_read_local_tags(mxf, &klv, metadata->read, metadata->ctx_size, metadata->type); } else { uint64_t next = avio_tell(s->pb) + klv.length; res = metadata->read(mxf, s->pb, 0, klv.length, klv.key, klv.offset); avio_seek(s->pb, next, SEEK_SET); } if (res < 0) { av_log(s, AV_LOG_ERROR, "error reading header metadata\n"); return res; } break; } } if (!metadata->read) avio_skip(s->pb, klv.length); } /* FIXME avoid seek */ if (!essence_offset) { av_log(s, AV_LOG_ERROR, "no essence\n"); return AVERROR_INVALIDDATA; } avio_seek(s->pb, essence_offset, SEEK_SET); mxf_compute_essence_containers(mxf); return mxf_parse_structural_metadata(mxf); }