diff --git a/player/video.c b/player/video.c
index 8599bbe702..6c93e1f576 100644
--- a/player/video.c
+++ b/player/video.c
@@ -1252,7 +1252,7 @@ void write_video(struct MPContext *mpctx)
         diff /= mpctx->video_speed;
         if (mpctx->time_frame < 0)
             diff += mpctx->time_frame;
-        frame->duration = MPCLAMP(diff, 0, 10) * 1e9;
+        frame->duration = MP_TIME_S_TO_NS(MPCLAMP(diff, 0, 10));
     }
 
     mpctx->video_pts = mpctx->next_frames[0]->pts;
diff --git a/video/out/vo.h b/video/out/vo.h
index e9e2f02901..895d6039fe 100644
--- a/video/out/vo.h
+++ b/video/out/vo.h
@@ -211,7 +211,7 @@ struct vo_frame {
     // If 0, present immediately.
     int64_t pts;
     // Approximate frame duration, in ns.
-    int duration;
+    double duration;
     // Realtime of estimated distance between 2 vsync events.
     double vsync_interval;
     // "ideal" display time within the vsync