diff --git a/libmpcodecs/vf_denoise3d.c b/libmpcodecs/vf_denoise3d.c
index e96a8844bd..03b4569991 100644
--- a/libmpcodecs/vf_denoise3d.c
+++ b/libmpcodecs/vf_denoise3d.c
@@ -63,7 +63,7 @@ static int config(struct vf_instance_s* vf,
 }
 
 
-void uninit(struct vf_instance_s* vf)
+static void uninit(struct vf_instance_s* vf)
 {
     free(vf->priv->Line);
 }