diff --git a/sub/osd_libass.c b/sub/osd_libass.c
index 126426c692..d28d8a6dae 100644
--- a/sub/osd_libass.c
+++ b/sub/osd_libass.c
@@ -685,8 +685,14 @@ static void append_ass(struct ass_state *ass, struct mp_osd_res *res,
 struct sub_bitmaps *osd_object_get_bitmaps(struct osd_state *osd,
                                            struct osd_object *obj, int format)
 {
-    if (obj->type == OSDTYPE_OSD && obj->osd_changed)
-        update_osd(osd, obj);
+    if (obj->type == OSDTYPE_OSD) {
+        if (obj->osd_changed) {
+            update_osd(osd, obj);
+        } else {
+            mp_require(obj->ass_packer);
+            goto done;
+        }
+    }
 
     if (!obj->ass_packer)
         obj->ass_packer = mp_ass_packer_alloc(obj);
@@ -704,6 +710,7 @@ struct sub_bitmaps *osd_object_get_bitmaps(struct osd_state *osd,
         }
     }
 
+done:;
     struct sub_bitmaps out_imgs = {0};
     mp_ass_packer_pack(obj->ass_packer, obj->ass_imgs, obj->num_externals + 1,
                        obj->changed, false, format, &out_imgs);