diff --git a/libavfilter/vf_aspect.c b/libavfilter/vf_aspect.c
index 4b58e5ea47..1bedd519c3 100644
--- a/libavfilter/vf_aspect.c
+++ b/libavfilter/vf_aspect.c
@@ -69,6 +69,7 @@ static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
     AspectContext *aspect = link->dst->priv;
 
     picref->video->pixel_aspect = aspect->aspect;
+    link->cur_buf = NULL;
     ff_start_frame(link->dst->outputs[0], picref);
 }