/*****************************************************************************
* input_clock.c: Clock/System date convertions, stream management
*****************************************************************************
- * Copyright (C) 1999-2004 the VideoLAN team
+ * Copyright (C) 1999-2008 the VideoLAN team
* $Id$
*
* Authors: Christophe Massiot <massiot@via.ecp.fr>
+ * Laurent Aimar < fenrir _AT_ videolan _DOT_ org >
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
#endif
#include <vlc_common.h>
-
-#include "input_internal.h"
+#include <vlc_input.h>
+#include "input_clock.h"
/*
* DISCUSSION : SYNCHRONIZATION METHOD
* new_average = (old_average * c_average + new_sample_value) / (c_average +1)
*/
-
-static void ClockNewRef( input_clock_t * p_pgrm,
- mtime_t i_clock, mtime_t i_sysdate );
-
/*****************************************************************************
* Constants
*****************************************************************************/
/* Latency introduced on DVDs with CR == 0 on chapter change - this is from
* my dice --Meuuh */
-#define CR_MEAN_PTS_GAP 300000
+#define CR_MEAN_PTS_GAP (300000)
/*****************************************************************************
- * ClockToSysdate: converts a movie clock to system date
+ * Structures
*****************************************************************************/
-static mtime_t ClockToSysdate( input_clock_t *cl, mtime_t i_clock )
+struct input_clock_t
{
- if( cl->i_synchro_state != SYNCHRO_OK )
- return 0;
+ /* Reference point */
+ bool b_has_reference;
+ struct
+ {
+ mtime_t i_clock;
+ mtime_t i_system;
+ } ref;
- return (i_clock - cl->cr_ref) * cl->i_rate / INPUT_RATE_DEFAULT +
- cl->sysdate_ref;
-}
+ /* Last point
+ * It is used to detect unexpected stream discontinuities */
+ struct
+ {
+ mtime_t i_clock;
+ mtime_t i_system;
+ } last;
-/*****************************************************************************
- * ClockCurrent: converts current system date to clock units
- *****************************************************************************
- * Caution : the synchro state must be SYNCHRO_OK for this to operate.
- *****************************************************************************/
-static mtime_t ClockCurrent( input_clock_t *cl )
-{
- return (mdate() - cl->sysdate_ref) * INPUT_RATE_DEFAULT / cl->i_rate +
- cl->cr_ref;
-}
+ /* Maixmal timestamp returned by input_clock_GetTS (in system unit) */
+ mtime_t i_ts_max;
-/*****************************************************************************
- * ClockNewRef: writes a new clock reference
- *****************************************************************************/
-static void ClockNewRef( input_clock_t *cl,
- mtime_t i_clock, mtime_t i_sysdate )
-{
- cl->cr_ref = i_clock;
- cl->sysdate_ref = i_sysdate ;
-}
+ /* Clock drift */
+ mtime_t i_delta_update; /* System time to wait for drift update */
+ mtime_t i_delta;
+ int i_delta_residue;
+
+ /* Current modifiers */
+ bool b_master;
+ int i_rate;
+
+ /* Static configuration */
+ int i_cr_average;
+};
+
+static mtime_t ClockStreamToSystem( input_clock_t *, mtime_t i_clock );
+static mtime_t ClockSystemToStream( input_clock_t *, mtime_t i_system );
+static void ClockSetReference( input_clock_t *, mtime_t i_clock, mtime_t i_system );
/*****************************************************************************
- * input_ClockInit: reinitializes the clock reference after a stream
- * discontinuity
+ * input_clock_New: create a new clock
*****************************************************************************/
-void input_ClockInit( input_clock_t *cl, bool b_master, int i_cr_average, int i_rate )
+input_clock_t *input_clock_New( bool b_master, int i_cr_average, int i_rate )
{
- cl->i_synchro_state = SYNCHRO_START;
-
- cl->last_cr = 0;
- cl->last_pts = 0;
- cl->last_sysdate = 0;
- cl->cr_ref = 0;
- cl->sysdate_ref = 0;
- cl->delta_cr = 0;
- cl->i_delta_cr_residue = 0;
+ input_clock_t *cl = malloc( sizeof(*cl) );
+ if( !cl )
+ return NULL;
+
+ cl->b_has_reference = false;
+ cl->ref.i_clock = 0;
+ cl->ref.i_system = 0;
+
+ cl->last.i_clock = 0;
+ cl->last.i_system = 0;
+
+ cl->i_ts_max = 0;
+
+ cl->i_delta = 0;
+ cl->i_delta_residue = 0;
+
+ cl->b_master = b_master;
cl->i_rate = i_rate;
cl->i_cr_average = i_cr_average;
- cl->b_master = b_master;
+ return cl;
}
/*****************************************************************************
- * input_ClockSetPCR: manages a clock reference
+ * input_clock_Delete: destroy a new clock
*****************************************************************************/
-void input_ClockSetPCR( input_thread_t *p_input,
- input_clock_t *cl, mtime_t i_clock )
+void input_clock_Delete( input_clock_t *cl )
{
- const bool b_synchronize = p_input->b_can_pace_control && cl->b_master;
- const mtime_t i_mdate = mdate();
+ free( cl );
+}
- if( ( cl->i_synchro_state != SYNCHRO_OK ) ||
- ( i_clock == 0 && cl->last_cr != 0 ) )
+/*****************************************************************************
+ * input_clock_SetPCR: manages a clock reference
+ *
+ * i_ck_stream: date in stream clock
+ * i_ck_system: date in system clock
+ *****************************************************************************/
+void input_clock_SetPCR( input_clock_t *cl,
+ vlc_object_t *p_log, bool b_can_pace_control,
+ mtime_t i_ck_stream, mtime_t i_ck_system )
+{
+ const bool b_synchronize = b_can_pace_control && cl->b_master;
+ bool b_reset_reference = false;
+
+ if( ( !cl->b_has_reference ) ||
+ ( i_ck_stream == 0 && cl->last.i_clock != 0 ) )
{
- /* Feed synchro with a new reference point. */
- ClockNewRef( cl, i_clock,
- __MAX( cl->last_pts + CR_MEAN_PTS_GAP, i_mdate ) );
- cl->i_synchro_state = SYNCHRO_OK;
-
- if( !b_synchronize )
- {
- cl->delta_cr = 0;
- cl->i_delta_cr_residue = 0;
- cl->last_update = 0;
- }
+ cl->i_delta_update = 0;
+
+ /* */
+ b_reset_reference= true;
}
- else if ( cl->last_cr != 0 &&
- ( (cl->last_cr - i_clock) > CR_MAX_GAP ||
- (cl->last_cr - i_clock) < - CR_MAX_GAP ) )
+ else if( cl->last.i_clock != 0 &&
+ ( (cl->last.i_clock - i_ck_stream) > CR_MAX_GAP ||
+ (cl->last.i_clock - i_ck_stream) < -CR_MAX_GAP ) )
{
/* Stream discontinuity, for which we haven't received a
* warning from the stream control facilities (dd-edited
* stream ?). */
- msg_Warn( p_input, "clock gap, unexpected stream discontinuity" );
- input_ClockInit( cl, cl->b_master, cl->i_cr_average, cl->i_rate );
+ msg_Warn( p_log, "clock gap, unexpected stream discontinuity" );
+ cl->i_ts_max = 0;
+
+ /* */
+ msg_Warn( p_log, "feeding synchro with a new reference point trying to recover from clock gap" );
+ b_reset_reference= true;
+ }
+ if( b_reset_reference )
+ {
+ cl->i_delta = 0;
+ cl->i_delta_residue = 0;
+
/* Feed synchro with a new reference point. */
- msg_Warn( p_input, "feeding synchro with a new reference point trying to recover from clock gap" );
- ClockNewRef( cl, i_clock,
- __MAX( cl->last_pts + CR_MEAN_PTS_GAP, i_mdate ) );
- cl->i_synchro_state = SYNCHRO_OK;
+ ClockSetReference( cl, i_ck_stream,
+ __MAX( cl->i_ts_max + CR_MEAN_PTS_GAP, i_ck_system ) );
}
- cl->last_cr = i_clock;
- cl->last_sysdate = i_mdate;
+ cl->last.i_clock = i_ck_stream;
+ cl->last.i_system = i_ck_system;
- if( b_synchronize )
- {
- /* Wait a while before delivering the packets to the decoder.
- * In case of multiple programs, we arbitrarily follow the
- * clock of the selected program. */
- if( !p_input->p->b_out_pace_control )
- {
- mtime_t i_wakeup = ClockToSysdate( cl, i_clock );
- while( (i_wakeup - mdate()) / CLOCK_FREQ > 1 )
- {
- msleep( CLOCK_FREQ );
- if( p_input->b_die ) i_wakeup = mdate();
- }
- mwait( i_wakeup );
- }
- }
- else if ( i_mdate - cl->last_update > 200000 )
+ if( !b_synchronize && i_ck_system - cl->i_delta_update > 200000 )
{
/* Smooth clock reference variations. */
- const mtime_t i_extrapoled_clock = ClockCurrent( cl );
+ const mtime_t i_extrapoled_clock = ClockSystemToStream( cl, i_ck_system );
/* Bresenham algorithm to smooth variations. */
- const mtime_t i_tmp = cl->delta_cr * (cl->i_cr_average - 1) +
- ( i_extrapoled_clock - i_clock ) * 1 +
- cl->i_delta_cr_residue;
+ const mtime_t i_tmp = cl->i_delta * (cl->i_cr_average - 1) +
+ ( i_extrapoled_clock - i_ck_stream ) * 1 +
+ cl->i_delta_residue;
- cl->i_delta_cr_residue = i_tmp % cl->i_cr_average;
- cl->delta_cr = i_tmp / cl->i_cr_average;
+ cl->i_delta_residue = i_tmp % cl->i_cr_average;
+ cl->i_delta = i_tmp / cl->i_cr_average;
- cl->last_update = i_mdate;
+ cl->i_delta_update = i_ck_system;
}
}
/*****************************************************************************
- * input_ClockResetPCR:
+ * input_clock_ResetPCR:
*****************************************************************************/
-void input_ClockResetPCR( input_clock_t *cl )
+void input_clock_ResetPCR( input_clock_t *cl )
{
- cl->i_synchro_state = SYNCHRO_REINIT;
- cl->last_pts = 0;
+ cl->b_has_reference = false;
+ cl->i_ts_max = 0;
}
/*****************************************************************************
- * input_ClockGetTS: manages a PTS or DTS
+ * input_clock_GetTS: manages a PTS or DTS
*****************************************************************************/
-mtime_t input_ClockGetTS( input_thread_t * p_input,
- input_clock_t *cl, mtime_t i_ts )
+mtime_t input_clock_GetTS( input_clock_t *cl,
+ mtime_t i_pts_delay, mtime_t i_ts )
{
- if( cl->i_synchro_state != SYNCHRO_OK )
+ mtime_t i_converted_ts;
+
+ if( !cl->b_has_reference )
return 0;
- cl->last_pts = ClockToSysdate( cl, i_ts + cl->delta_cr );
- return cl->last_pts + p_input->i_pts_delay;
+ /* */
+ i_converted_ts = ClockStreamToSystem( cl, i_ts + cl->i_delta );
+ if( i_converted_ts > cl->i_ts_max )
+ cl->i_ts_max = i_converted_ts;
+
+ return i_converted_ts + i_pts_delay;
}
/*****************************************************************************
- * input_ClockSetRate:
+ * input_clock_SetRate:
*****************************************************************************/
-void input_ClockSetRate( input_clock_t *cl, int i_rate )
+void input_clock_SetRate( input_clock_t *cl, int i_rate )
{
/* Move the reference point */
- if( cl->i_synchro_state == SYNCHRO_OK )
- ClockNewRef( cl, cl->last_cr, cl->last_sysdate );
+ if( cl->b_has_reference )
+ ClockSetReference( cl, cl->last.i_clock, cl->last.i_system );
cl->i_rate = i_rate;
}
+/*****************************************************************************
+ * input_clock_SetMaster:
+ *****************************************************************************/
+void input_clock_SetMaster( input_clock_t *cl, bool b_master )
+{
+ cl->b_master = b_master;
+}
+
+/*****************************************************************************
+ * input_clock_GetWakeup
+ *****************************************************************************/
+mtime_t input_clock_GetWakeup( input_clock_t *cl )
+{
+ /* Not synchronized, we cannot wait */
+ if( !cl->b_has_reference )
+ return 0;
+
+ /* We must not wait if we are not the master clock */
+ if( !cl->b_master )
+ return 0;
+
+ /* */
+ return ClockStreamToSystem( cl, cl->last.i_clock );
+}
+
+/*****************************************************************************
+ * ClockStreamToSystem: converts a movie clock to system date
+ *****************************************************************************/
+static mtime_t ClockStreamToSystem( input_clock_t *cl, mtime_t i_clock )
+{
+ if( !cl->b_has_reference )
+ return 0;
+
+ return ( i_clock - cl->ref.i_clock ) * cl->i_rate / INPUT_RATE_DEFAULT +
+ cl->ref.i_system;
+}
+
+/*****************************************************************************
+ * ClockSystemToStream: converts a system date to movie clock
+ *****************************************************************************
+ * Caution : a valid reference point is needed for this to operate.
+ *****************************************************************************/
+static mtime_t ClockSystemToStream( input_clock_t *cl, mtime_t i_system )
+{
+ assert( cl->b_has_reference );
+ return ( i_system - cl->ref.i_system ) * INPUT_RATE_DEFAULT / cl->i_rate +
+ cl->ref.i_clock;
+}
+
+/*****************************************************************************
+ * ClockSetReference: writes a new clock reference
+ *****************************************************************************/
+static void ClockSetReference( input_clock_t *cl,
+ mtime_t i_clock, mtime_t i_system )
+{
+ cl->b_has_reference = true;
+ cl->ref.i_clock = i_clock;
+ cl->ref.i_system = i_system;
+}
+
+