diff --git a/libavfilter/vf_format.c b/libavfilter/vf_format.c
index c9ccad9b25..25b3d19952 100644
--- a/libavfilter/vf_format.c
+++ b/libavfilter/vf_format.c
@@ -116,6 +116,7 @@ static const AVFilterPad avfilter_vf_format_inputs[] = {
     {
         .name             = "default",
         .type             = AVMEDIA_TYPE_VIDEO,
+        .get_video_buffer = ff_null_get_video_buffer,
     },
     { NULL }
 };
@@ -158,6 +159,7 @@ static const AVFilterPad avfilter_vf_noformat_inputs[] = {
     {
         .name             = "default",
         .type             = AVMEDIA_TYPE_VIDEO,
+        .get_video_buffer = ff_null_get_video_buffer,
     },
     { NULL }
 };