diff --git a/libavutil/timecode.c b/libavutil/timecode.c
index 5106f642b9..280e4cacfb 100644
--- a/libavutil/timecode.c
+++ b/libavutil/timecode.c
@@ -46,7 +46,7 @@ int av_timecode_adjust_ntsc_framenum2(int framenum, int fps)
     d = framenum / frames_per_10mins;
     m = framenum % frames_per_10mins;
 
-    return framenum + 9 * drop_frames * d + drop_frames * ((m - drop_frames) / (frames_per_10mins / 10));
+    return framenum + 9U * drop_frames * d + drop_frames * ((m - drop_frames) / (frames_per_10mins / 10));
 }
 
 uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum)