diff --git a/libavutil/opt.c b/libavutil/opt.c
index c064357f70..21506f7709 100644
--- a/libavutil/opt.c
+++ b/libavutil/opt.c
@@ -1225,6 +1225,8 @@ void av_opt_set_defaults2(void *s, int mask, int flags)
                 write_number(s, opt, dst, 1, 1, opt->default_val.i64);
                 break;
             case AV_OPT_TYPE_BINARY:
+                set_string_binary(s, opt, opt->default_val.str, dst);
+                break;
             case AV_OPT_TYPE_DICT:
                 /* Cannot set defaults for these types */
             break;
diff --git a/tests/ref/fate/opt b/tests/ref/fate/opt
new file mode 100644
index 0000000000..e69de29bb2