diff --git a/libavfilter/avfilter.c b/libavfilter/avfilter.c
index 361c8802d4..675f9d6844 100644
--- a/libavfilter/avfilter.c
+++ b/libavfilter/avfilter.c
@@ -1,5 +1,5 @@
 /*
- * Filter layer
+ * filter layer
  * copyright (c) 2007 Bobby Bingham
  *
  * This file is part of FFmpeg.