diff --git a/libavformat/mxfenc.c b/libavformat/mxfenc.c
index 03409079cb..eaaece35dd 100644
--- a/libavformat/mxfenc.c
+++ b/libavformat/mxfenc.c
@@ -661,7 +661,7 @@ static void mxf_write_mpegvideo_desc(AVFormatContext *s, AVStream *st)
         f1 *= 2;
     }
 
-    mxf_write_local_tag(pb, 16, 0x320D);
+    mxf_write_local_tag(pb, 12+sc->interlaced*4, 0x320D);
     put_be32(pb, sc->interlaced ? 2 : 1);
     put_be32(pb, 4);
     put_be32(pb, f1);