preroll

diff --git a/src/input/es_out.c b/src/input/es_out.c
index 89bff72..34a246d 100644
--- a/src/input/es_out.c
+++ b/src/input/es_out.c
@@ -159,6 +159,7 @@ struct es_out_sys_t

     /* Current preroll */
     mtime_t     i_preroll_end;
+    bool        b_prerolling;

     /* Used for buffering */
     bool        b_buffering;
@@ -322,6 +323,7 @@ es_out_t *input_EsOutNew( input_thread_t *p_input, int i_rate )
     p_sys->i_buffering_extra_stream = 0;
     p_sys->i_buffering_extra_system = 0;
     p_sys->i_preroll_end = -1;
+    p_sys->b_prerolling = false;

     p_sys->p_sout_record = NULL;

@@ -622,6 +624,7 @@ static void EsOutChangePosition( es_out_t *out )
     p_sys->i_buffering_extra_stream = 0;
     p_sys->i_buffering_extra_system = 0;
     p_sys->i_preroll_end = -1;
+    p_sys->b_prerolling = false;
 }


@@ -664,6 +667,7 @@ static void EsOutDecodersStopBuffering( es_out_t *out, bool b_forced )
               (int)(i_stream_duration/1000), (int)(i_system_duration/1000) );
     p_sys->b_buffering = false;
     p_sys->i_preroll_end = -1;
+    p_sys->b_prerolling = false;

     if( p_sys->i_buffering_extra_initial > 0 )
     {
@@ -851,6 +855,7 @@ static void EsOutFrameNext( es_out_t *out )
                                                 INPUT_RATE_DEFAULT / i_rate;

     p_sys->i_preroll_end = -1;
+    p_sys->b_prerolling = false;
 }
 static mtime_t EsOutGetBuffering( es_out_t *out )
 {
@@ -1946,7 +1951,7 @@ static int EsOutSend( es_out_t *out, es_out_id_t *es, block_t *p_block )
     vlc_mutex_lock( &p_sys->lock );

     /* Mark preroll blocks */
-    if( p_sys->i_preroll_end >= 0 )
+    if( p_sys->b_prerolling )
     {
         int64_t i_date = p_block->i_pts;
         if( p_block->i_pts <= VLC_TS_INVALID )
@@ -1954,6 +1959,9 @@ static int EsOutSend( es_out_t *out, es_out_id_t *es, block_t *p_block )

         if( i_date < p_sys->i_preroll_end )
             p_block->i_flags |= BLOCK_FLAG_PREROLL;
+        else
+            p_sys->b_prerolling = false;
+
     }

     if( !es->p_dec )
@@ -2440,6 +2448,7 @@ static int EsOutControlLocked( es_out_t *out, int i_query, va_list args )
                 return VLC_EGENERIC;

             p_sys->i_preroll_end = i_date;
+            p_sys->b_prerolling = (i_date >= 0);

             return VLC_SUCCESS;
         }