diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index c41779ad40..1c32339754 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -3439,6 +3439,9 @@ typedef struct AVCodec {
 
     /**
      * Initialize codec static data, called from avcodec_register().
+     *
+     * This is not intended for time consuming operations as it is
+     * run for every codec regardless of that codec being used.
      */
     void (*init_static_data)(struct AVCodec *codec);