diff --git a/encoder/encoder.c b/encoder/encoder.c
index e81172d..cb01802 100644
--- a/encoder/encoder.c
+++ b/encoder/encoder.c
@@ -1160,8 +1160,8 @@ x264_t *x264_encoder_open( x264_param_t *param )
         * ( h->param.rc.i_rc_method == X264_RC_ABR ? pow( 0.95, h->param.rc.i_qp_min )
           : pow( 0.95, h->param.rc.i_qp_constant ) * X264_MAX( 1, h->param.rc.f_ip_factor )));

-    CHECKED_MALLOC( h->nal_buffer, h->out.i_bitstream * 3/2 + 4 );
     h->nal_buffer_size = h->out.i_bitstream * 3/2 + 4;
+    CHECKED_MALLOC( h->nal_buffer, h->nal_buffer_size );

     if( h->param.i_threads > 1 &&
         x264_threadpool_init( &h->threadpool, h->param.i_threads, (void*)x264_encoder_thread_init, h ) )