diff --git a/libavcodec/x264.c b/libavcodec/x264.c
index 4fc2c64487..1248e4fecf 100644
--- a/libavcodec/x264.c
+++ b/libavcodec/x264.c
@@ -1,6 +1,6 @@
 /*
  * H.264 encoding using the x264 library
- * Copyright (C) 2005  Måns Rullgård <mru@inprovide.com>
+ * Copyright (C) 2005  Mans Rullgard <mru@inprovide.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -136,6 +136,9 @@ X264_init(AVCodecContext *avctx)
     x4->params.rc.i_rc_buffer_size = avctx->rc_buffer_size / 1000;
     if(avctx->rc_buffer_size)
         x4->params.rc.b_cbr = 1;
+   x4->params.i_bframe = avctx->max_b_frames;
+   x4->params.b_cabac = avctx->coder_type == FF_CODER_TYPE_AC;
+
     x4->params.rc.i_qp_min = avctx->qmin;
     x4->params.rc.i_qp_max = avctx->qmax;
     x4->params.rc.i_qp_step = avctx->max_qdiff;