Some files set the PreviousPartition field to point to its own offset. If we are parsing forward the Previous partition is immediately known and its value could be used, otherwise we can safely point to the header.
Reported-By: Jean Baptiste Kempf <[email protected]> --- libavformat/mxfdec.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c index 734c50a..39ab462 100644 --- a/libavformat/mxfdec.c +++ b/libavformat/mxfdec.c @@ -478,6 +478,26 @@ static int mxf_read_partition_pack(void *arg, AVIOContext *pb, int tag, int size avio_read(pb, op, sizeof(UID)); nb_essence_containers = avio_rb32(pb); + if (partition->this_partition && + partition->previous_partition == partition->this_partition) { + av_log(mxf->fc, AV_LOG_ERROR, + "PreviousPartition equal to ThisPartition %"PRIx64"\n", + partition->previous_partition); + /* override with the actual previous partition offset */ + if (!mxf->parsing_backward && mxf->last_forward_partition > 1) { + MXFPartition *prev = + mxf->partitions + mxf->last_forward_partition - 2; + partition->previous_partition = prev->this_partition; + } + /* if no previous body partition are found point to the header + * partition */ + if (partition->previous_partition == partition->this_partition); + partition->previous_partition = 0; + av_log(mxf->fc, AV_LOG_ERROR, + "Overriding PreviousPartition with %"PRIx64"\n", + partition->previous_partition); + } + /* some files don'thave FooterPartition set in every partition */ if (footer_partition) { if (mxf->footer_partition && mxf->footer_partition != footer_partition) { -- 1.8.5.1 _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
