diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
index a08d4f7977..ccb933ae33 100644
--- a/libavformat/img2dec.c
+++ b/libavformat/img2dec.c
@@ -220,8 +220,10 @@ int ff_img_read_header(AVFormatContext *s1)
         avpriv_set_pts_info(st, 64, 1, 1000000000);
     } else if (s->ts_from_file)
         avpriv_set_pts_info(st, 64, 1, 1);
-    else
+    else {
         avpriv_set_pts_info(st, 64, s->framerate.den, s->framerate.num);
+        st->avg_frame_rate = s->framerate;
+    }
 
     if (s->width && s->height) {
         st->codecpar->width  = s->width;