lavfi: add avfilter_default_filter_name()

The function is modelled after av_default_item_name(), and will print the
name of the instance filter if defined, otherwise the name of the filter.

This allows to show the instance name in the log, which is useful when
debugging complex filter graphs.

1 files changed, 1 insertions, 6 deletions

diff --git a/libavfilter/vf_ass.c b/libavfilter/vf_ass.c
index c828699ae1..3503b2665f 100644
--- a/libavfilter/vf_ass.c
+++ b/libavfilter/vf_ass.c
@@ -54,14 +54,9 @@ static const AVOption ass_options[] = {
     {NULL},
 };
 
-static const char *ass_get_name(void *ctx)
-{
-    return "ass";
-}
-
 static const AVClass ass_class = {
     "AssContext",
-    ass_get_name,
+    avfilter_default_filter_name,
     ass_options
 };