[FFmpeg-devel] [PATCH 3/5] avformat/mxfdec: guess wrapping of tracks by other tracks with the same body sid

[Marton Balint]

This affects the following samples:

samples/ffmpeg-bugs/roundup/issue1775/av_seek_frame_failure.mxf
samples/ffmpeg-bugs/trac/ticket1957/16ch.mxf
samples/ffmpeg-bugs/trac/ticket5016/r0.mxf
samples/ffmpeg-bugs/trac/ticket5016/r1.mxf
samples/ffmpeg-bugs/trac/ticket5316/hq.MXF
samples/ffmpeg-bugs/trac/ticket5316/hqx.MXF

Some AVPacket->pos values are changed because for frame wrapped tracks we point
to the KLV offset and not the data.

Signed-off-by: Marton Balint <cus at passwd.hu>
---
 libavformat/mxfdec.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/libavformat/mxfdec.c b/libavformat/mxfdec.c
index 18c038c3f6..236294880e 100644
--- a/libavformat/mxfdec.c
+++ b/libavformat/mxfdec.c
@@ -2144,6 +2144,16 @@ static int mxf_add_metadata_stream(MXFContext *mxf, MXFTrack *track)
     return 0;
 }
 
+static MXFWrappingScheme mxf_get_wrapping_by_body_sid(AVFormatContext *s, int body_sid)
+{
+    for (int i = 0; i < s->nb_streams; i++) {
+        MXFTrack *track = s->streams[i]->priv_data;
+        if (track && track->body_sid == body_sid && track->wrapping != UnknownWrapped)
+            return track->wrapping;
+    }
+    return UnknownWrapped;
+}
+
 static int mxf_parse_structural_metadata(MXFContext *mxf)
 {
     MXFPackage *material_package = NULL;
@@ -2553,6 +2563,12 @@ static int mxf_parse_structural_metadata(MXFContext *mxf)
         }
     }
 
+    for (int i = 0; i < mxf->fc->nb_streams; i++) {
+        MXFTrack *track = mxf->fc->streams[i]->priv_data;
+        if (track && track->body_sid && track->wrapping == UnknownWrapped)
+            track->wrapping = mxf_get_wrapping_by_body_sid(mxf->fc, track->body_sid);
+    }
+
     ret = 0;
 fail_and_free:
     return ret;
@@ -2913,16 +2929,6 @@ static int mxf_parse_handle_partition_or_eof(MXFContext *mxf)
     return mxf->parsing_backward ? mxf_seek_to_previous_partition(mxf) : 1;
 }
 
-static MXFWrappingScheme mxf_get_wrapping_by_body_sid(AVFormatContext *s, int body_sid)
-{
-    for (int i = 0; i < s->nb_streams; i++) {
-        MXFTrack *track = s->streams[i]->priv_data;
-        if (track && track->body_sid == body_sid && track->wrapping != UnknownWrapped)
-            return track->wrapping;
-    }
-    return UnknownWrapped;
-}
-
 /**
  * Figures out the proper offset and length of the essence container in each partition
  */
-- 
2.16.4