-static void GREY_I420 ( vout_thread_t *, picture_t *, picture_t * );
-static void GREY_YUY2 ( vout_thread_t *, picture_t *, picture_t * );
+static void GREY_I420( filter_t *, picture_t *, picture_t * );
+static void GREY_YUY2( filter_t *, picture_t *, picture_t * );
+
+static picture_t *GREY_I420_Filter( filter_t *, picture_t * );
+static picture_t *GREY_YUY2_Filter( filter_t *, picture_t * );