diff --git a/libavformat/libnut.c b/libavformat/libnut.c
index 239ba36a3c..d4e7201ab9 100644
--- a/libavformat/libnut.c
+++ b/libavformat/libnut.c
@@ -11,7 +11,7 @@ typedef struct {
 } NUTContext;
 
 static const CodecTag nut_tags[] = {
-    { CODEC_ID_MPEG4,  MKTAG('m', 'p', '4', 's') },
+    { CODEC_ID_MPEG4,  MKTAG('m', 'p', '4', 'v') },
     { CODEC_ID_MP3,    MKTAG('m', 'p', '3', ' ') },
     { CODEC_ID_VORBIS, MKTAG('v', 'r', 'b', 's') },
     { 0, 0 },