diff --git a/libavcodec/cook.c b/libavcodec/cook.c
index 419e1c4c23..9a290c3d40 100644
--- a/libavcodec/cook.c
+++ b/libavcodec/cook.c
@@ -365,7 +365,7 @@ static av_cold int cook_decode_close(AVCodecContext *avctx)
  * Fill the gain array for the timedomain quantization.
  *
  * @param q                 pointer to the COOKContext
- * @param gaininfo[9]       array of gain indexes
+ * @param gaininfo  array of gain indexes
  */
 
 static void decode_gain_info(GetBitContext *gb, int *gaininfo)