diff --git a/video/filter/vf_format.c b/video/filter/vf_format.c
index 71e3ad7669..d37778e38d 100644
--- a/video/filter/vf_format.c
+++ b/video/filter/vf_format.c
@@ -56,10 +56,20 @@ static int config(struct vf_instance *vf, int width, int height,
     return vf_next_config(vf, width, height, d_width, d_height, flags, vf->priv->outfmt);
 }
 
+static struct mp_image *filter(struct vf_instance *vf, struct mp_image *mpi)
+{
+    // As documented in the manpage, the user can easily provoke crashes
+    if (vf->priv->outfmt)
+        mp_image_setfmt(mpi, vf->priv->outfmt);
+    return mpi;
+}
+
 static int vf_open(vf_instance_t *vf, char *args){
     vf->query_format=query_format;
-    if (vf->priv->outfmt)
+    if (vf->priv->outfmt) {
         vf->config=config;
+        vf->filter=filter;
+    }
     return 1;
 }