From: Tomas Härdin <[email protected]> This replaces the old essence_offset code.
Signed-off-by: Janne Grunau <[email protected]> --- libavformat/mxfdec.c | 53 ++++++++++++++++++++++++++++++++++--------------- 1 files changed, 37 insertions(+), 16 deletions(-) diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c index 6ce857f..44deee2 100644 --- a/libavformat/mxfdec.c +++ b/libavformat/mxfdec.c @@ -190,9 +190,6 @@ typedef struct { uint8_t *local_tags; int local_tags_count; uint64_t footer_partition; - int64_t essence_offset; - int first_essence_kl_length; - int64_t first_essence_length; KLVPacket current_klv_data; int current_klv_index; int run_in; @@ -1021,6 +1018,34 @@ static int mxf_get_sorted_table_segments(MXFContext *mxf, int *nb_sorted_segment return 0; } +/** + * Computes the absolute file offset of the given essence container offset + */ +static int mxf_absolute_bodysid_offset(MXFContext *mxf, int body_sid, int64_t offset, int64_t *offset_out) +{ + int x; + int64_t offset_in = offset; /* for logging */ + + for (x = 0; x < mxf->partitions_count; x++) { + MXFPartition *p = &mxf->partitions[x]; + + if (p->body_sid != body_sid) + continue; + + if (offset < p->essence_length || !p->essence_length) { + *offset_out = p->essence_offset + offset; + return 0; + } + + offset -= p->essence_length; + } + + av_log(mxf->fc, AV_LOG_ERROR, "failed to find absolute offset of %lx in BodySID %i - partial file?\n", + offset_in, body_sid); + + return AVERROR_INVALIDDATA; +} + static int mxf_parse_index(MXFContext *mxf, int track_id, AVStream *st) { int64_t accumulated_offset = 0; @@ -1107,10 +1132,10 @@ static int mxf_parse_index(MXFContext *mxf, int track_id, AVStream *st) flags = AVINDEX_KEYFRAME; } - if (k > 0 && pos < mxf->first_essence_length && accumulated_offset == 0) - pos += mxf->first_essence_kl_length; - - pos += mxf->essence_offset; + if (mxf_absolute_bodysid_offset(mxf, tableseg->body_sid, pos, &pos) < 0) { + /* probably partial file - no point going further for this stream */ + break; + } av_dlog(mxf->fc, "Stream %d IndexEntry %d TrackID %d Offset %"PRIx64" Timestamp %"PRId64"\n", st->index, st->nb_index_entries, track_id, pos, sample_duration * st->nb_index_entries); @@ -1543,6 +1568,7 @@ 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; @@ -1574,13 +1600,8 @@ static int mxf_read_header(AVFormatContext *s, AVFormatParameters *ap) compute_partition_essence_offset(s, mxf, &klv); } - if (!mxf->essence_offset) - mxf->essence_offset = klv.offset; - - if (!mxf->first_essence_kl_length && IS_KLV_KEY(klv.key, mxf_essence_element_key)) { - mxf->first_essence_kl_length = avio_tell(s->pb) - klv.offset; - mxf->first_essence_length = klv.length; - } + if (!essence_offset) + essence_offset = klv.offset; /* seek to footer, previous partition or stop */ if (mxf_parse_handle_essence(mxf) <= 0) @@ -1614,11 +1635,11 @@ static int mxf_read_header(AVFormatContext *s, AVFormatParameters *ap) avio_skip(s->pb, klv.length); } /* FIXME avoid seek */ - if (!mxf->essence_offset) { + if (!essence_offset) { av_log(s, AV_LOG_ERROR, "no essence\n"); return AVERROR_INVALIDDATA; } - avio_seek(s->pb, mxf->essence_offset, SEEK_SET); + avio_seek(s->pb, essence_offset, SEEK_SET); mxf_compute_essence_containers(mxf); -- 1.7.8 _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
