/*****************************************************************************
- * input_clock.c: Clock/System date convertions, stream management
+ * clock.c: Clock/System date convertions, stream management
*****************************************************************************
- * Copyright (C) 1999-2004 the VideoLAN team
+ * Copyright (C) 1999-2008 the VideoLAN team
+ * Copyright (C) 2008 Laurent Aimar
* $Id$
*
* 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
/*****************************************************************************
* Preamble
*****************************************************************************/
-#include <vlc/vlc.h>
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
-#include "input_internal.h"
+#include <vlc_common.h>
+#include <vlc_input.h>
+#include "clock.h"
+#include <assert.h>
+
+/* TODO:
+ * - clean up locking once clock code is stable
+ *
+ */
/*
* DISCUSSION : SYNCHRONIZATION METHOD
* in all the FIFOs, but it may be not enough.
*/
-/* p_input->p->i_cr_average : Maximum number of samples used to compute the
+/* i_cr_average : Maximum number of samples used to compute the
* dynamic average value.
* We use the following formula :
* 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
*****************************************************************************/
/* Maximum gap allowed between two CRs. */
-#define CR_MAX_GAP (I64C(2000000)*100/9)
+#define CR_MAX_GAP (INT64_C(2000000)*100/9)
/* 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)
+
+/*****************************************************************************
+ * Structures
+ *****************************************************************************/
+
+/**
+ * This structure holds long term average
+ */
+typedef struct
+{
+ mtime_t i_value;
+ int i_residue;
+
+ int i_count;
+ int i_divider;
+} average_t;
+static void AvgInit( average_t *, int i_divider );
+static void AvgClean( average_t * );
+
+static void AvgReset( average_t * );
+static void AvgUpdate( average_t *, mtime_t i_value );
+static mtime_t AvgGet( average_t * );
+static void AvgRescale( average_t *, int i_divider );
+
+/* */
+typedef struct
+{
+ mtime_t i_stream;
+ mtime_t i_system;
+} clock_point_t;
+
+static inline clock_point_t clock_point_Create( mtime_t i_stream, mtime_t i_system )
+{
+ clock_point_t p = { .i_stream = i_stream, .i_system = i_system };
+ return p;
+}
+
+/* */
+struct input_clock_t
+{
+ /* */
+ vlc_mutex_t lock;
+
+ /* Reference point */
+ bool b_has_reference;
+ clock_point_t ref;
+
+ /* Last point
+ * It is used to detect unexpected stream discontinuities */
+ clock_point_t last;
+
+ /* Maximal timestamp returned by input_clock_ConvertTS (in system unit) */
+ mtime_t i_ts_max;
+
+ /* Clock drift */
+ mtime_t i_next_drift_update;
+ average_t drift;
+
+ /* Current modifiers */
+ int i_rate;
+ mtime_t i_pts_delay;
+ bool b_paused;
+ mtime_t i_pause_date;
+};
+
+static mtime_t ClockStreamToSystem( input_clock_t *, mtime_t i_stream );
+static mtime_t ClockSystemToStream( input_clock_t *, mtime_t i_system );
/*****************************************************************************
- * ClockToSysdate: converts a movie clock to system date
+ * input_clock_New: create a new clock
*****************************************************************************/
-static mtime_t ClockToSysdate( input_clock_t *cl, mtime_t i_clock )
+input_clock_t *input_clock_New( int i_rate )
{
- if( cl->i_synchro_state != SYNCHRO_OK )
- return 0;
+ input_clock_t *cl = malloc( sizeof(*cl) );
+ if( !cl )
+ return NULL;
+
+ vlc_mutex_init( &cl->lock );
+ cl->b_has_reference = false;
+ cl->ref = clock_point_Create( VLC_TS_INVALID, VLC_TS_INVALID );
- return (i_clock - cl->cr_ref) * cl->i_rate / INPUT_RATE_DEFAULT +
- cl->sysdate_ref;
+ cl->last = clock_point_Create( VLC_TS_INVALID, VLC_TS_INVALID );
+
+ cl->i_ts_max = VLC_TS_INVALID;
+
+ cl->i_next_drift_update = VLC_TS_INVALID;
+ AvgInit( &cl->drift, 10 );
+
+ cl->i_rate = i_rate;
+ cl->i_pts_delay = 0;
+ cl->b_paused = false;
+ cl->i_pause_date = VLC_TS_INVALID;
+
+ return cl;
}
/*****************************************************************************
- * ClockCurrent: converts current system date to clock units
- *****************************************************************************
- * Caution : the synchro state must be SYNCHRO_OK for this to operate.
+ * input_clock_Delete: destroy a new clock
+ *****************************************************************************/
+void input_clock_Delete( input_clock_t *cl )
+{
+ AvgClean( &cl->drift );
+ vlc_mutex_destroy( &cl->lock );
+ free( cl );
+}
+
+/*****************************************************************************
+ * input_clock_Update: manages a clock reference
+ *
+ * i_ck_stream: date in stream clock
+ * i_ck_system: date in system clock
*****************************************************************************/
-static mtime_t ClockCurrent( input_clock_t *cl )
+void input_clock_Update( input_clock_t *cl,
+ vlc_object_t *p_log, bool b_can_pace_control,
+ mtime_t i_ck_stream, mtime_t i_ck_system )
{
- return (mdate() - cl->sysdate_ref) * INPUT_RATE_DEFAULT / cl->i_rate +
- cl->cr_ref;
+ bool b_reset_reference = false;
+
+ assert( i_ck_stream > VLC_TS_INVALID && i_ck_system > VLC_TS_INVALID );
+
+ vlc_mutex_lock( &cl->lock );
+
+ if( !cl->b_has_reference )
+ {
+ /* */
+ b_reset_reference= true;
+ }
+ else if( cl->last.i_stream > VLC_TS_INVALID &&
+ ( (cl->last.i_stream - i_ck_stream) > CR_MAX_GAP ||
+ (cl->last.i_stream - 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_log, "clock gap, unexpected stream discontinuity" );
+ cl->i_ts_max = VLC_TS_INVALID;
+
+ /* */
+ 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_next_drift_update = VLC_TS_INVALID;
+ AvgReset( &cl->drift );
+
+ /* Feed synchro with a new reference point. */
+ cl->b_has_reference = true;
+ cl->ref = clock_point_Create( i_ck_stream,
+ __MAX( cl->i_ts_max + CR_MEAN_PTS_GAP, i_ck_system ) );
+ }
+
+ if( !b_can_pace_control && cl->i_next_drift_update < i_ck_system )
+ {
+ const mtime_t i_converted = ClockSystemToStream( cl, i_ck_system );
+
+ AvgUpdate( &cl->drift, i_converted - i_ck_stream );
+
+ cl->i_next_drift_update = i_ck_system + CLOCK_FREQ/5; /* FIXME why that */
+ }
+ cl->last = clock_point_Create( i_ck_stream, i_ck_system );
+
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
- * ClockNewRef: writes a new clock reference
+ * input_clock_Reset:
*****************************************************************************/
-static void ClockNewRef( input_clock_t *cl,
- mtime_t i_clock, mtime_t i_sysdate )
+void input_clock_Reset( input_clock_t *cl )
{
- cl->cr_ref = i_clock;
- cl->sysdate_ref = i_sysdate ;
+ vlc_mutex_lock( &cl->lock );
+
+ cl->b_has_reference = false;
+ cl->ref = clock_point_Create( VLC_TS_INVALID, VLC_TS_INVALID );
+ cl->i_ts_max = VLC_TS_INVALID;
+
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
- * input_ClockInit: reinitializes the clock reference after a stream
- * discontinuity
+ * input_clock_ChangeRate:
*****************************************************************************/
-void input_ClockInit( input_thread_t *p_input,
- input_clock_t *cl, vlc_bool_t b_master, int i_cr_average )
+void input_clock_ChangeRate( input_clock_t *cl, int i_rate )
{
- cl->i_synchro_state = SYNCHRO_START;
+ vlc_mutex_lock( &cl->lock );
- 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;
- cl->i_rate = p_input->p->i_rate;
+ /* Move the reference point */
+ if( cl->b_has_reference )
+ {
+ cl->last.i_system = ClockStreamToSystem( cl, cl->last.i_stream );
+ cl->ref = cl->last;
+ }
- cl->i_cr_average = i_cr_average;
+ cl->i_rate = i_rate;
- cl->b_master = b_master;
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
- * input_ClockSetPCR: manages a clock reference
+ * input_clock_ChangePause:
*****************************************************************************/
-void input_ClockSetPCR( input_thread_t *p_input,
- input_clock_t *cl, mtime_t i_clock )
+void input_clock_ChangePause( input_clock_t *cl, bool b_paused, mtime_t i_date )
{
- const vlc_bool_t b_synchronize = p_input->b_can_pace_control && cl->b_master;
- const mtime_t i_mdate = mdate();
+ vlc_mutex_lock( &cl->lock );
+ assert( (!cl->b_paused) != (!b_paused) );
- if( ( cl->i_synchro_state != SYNCHRO_OK ) ||
- ( i_clock == 0 && cl->last_cr != 0 ) )
+ if( cl->b_paused )
{
- /* 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;
+ const mtime_t i_duration = i_date - cl->i_pause_date;
- if( !b_synchronize )
+ if( cl->b_has_reference && i_duration > 0 )
{
- cl->delta_cr = 0;
- cl->i_delta_cr_residue = 0;
- cl->last_update = 0;
+ cl->ref.i_system += i_duration;
+ cl->last.i_system += i_duration;
}
}
- else if ( cl->last_cr != 0 &&
- ( (cl->last_cr - i_clock) > CR_MAX_GAP ||
- (cl->last_cr - i_clock) < - CR_MAX_GAP ) )
+ cl->i_pause_date = i_date;
+ cl->b_paused = b_paused;
+
+ vlc_mutex_unlock( &cl->lock );
+}
+
+/*****************************************************************************
+ * input_clock_GetWakeup
+ *****************************************************************************/
+mtime_t input_clock_GetWakeup( input_clock_t *cl )
+{
+ mtime_t i_wakeup = 0;
+
+ vlc_mutex_lock( &cl->lock );
+
+ /* Synchronized, we can wait */
+ if( cl->b_has_reference )
+ i_wakeup = ClockStreamToSystem( cl, cl->last.i_stream );
+
+ vlc_mutex_unlock( &cl->lock );
+
+ return i_wakeup;
+}
+
+/*****************************************************************************
+ * input_clock_ConvertTS
+ *****************************************************************************/
+int input_clock_ConvertTS( input_clock_t *cl,
+ int *pi_rate, mtime_t *pi_ts0, mtime_t *pi_ts1,
+ mtime_t i_ts_bound )
+{
+ mtime_t i_pts_delay;
+
+ assert( pi_ts0 );
+ vlc_mutex_lock( &cl->lock );
+
+ if( pi_rate )
+ *pi_rate = cl->i_rate;
+
+ if( !cl->b_has_reference )
{
- /* 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( p_input, cl, cl->b_master, cl->i_cr_average );
- /* 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;
+ vlc_mutex_unlock( &cl->lock );
+ *pi_ts0 = VLC_TS_INVALID;
+ if( pi_ts1 )
+ *pi_ts1 = VLC_TS_INVALID;
+ return VLC_EGENERIC;
}
- cl->last_cr = i_clock;
- cl->last_sysdate = i_mdate;
-
- if( b_synchronize )
+ /* */
+ if( *pi_ts0 > VLC_TS_INVALID )
{
- /* 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 );
- }
+ *pi_ts0 = ClockStreamToSystem( cl, *pi_ts0 + AvgGet( &cl->drift ) );
+ if( *pi_ts0 > cl->i_ts_max )
+ cl->i_ts_max = *pi_ts0;
+ *pi_ts0 += cl->i_pts_delay;
}
- else if ( i_mdate - cl->last_update > 200000 )
+
+ /* XXX we do not ipdate i_ts_max on purpose */
+ if( pi_ts1 && *pi_ts1 > VLC_TS_INVALID )
{
- /* Smooth clock reference variations. */
- const mtime_t i_extrapoled_clock = ClockCurrent( cl );
- /* 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;
+ *pi_ts1 = ClockStreamToSystem( cl, *pi_ts1 + AvgGet( &cl->drift ) ) +
+ cl->i_pts_delay;
+ }
+
+ i_pts_delay = cl->i_pts_delay;
+ vlc_mutex_unlock( &cl->lock );
- cl->i_delta_cr_residue = i_tmp % cl->i_cr_average;
- cl->delta_cr = i_tmp / cl->i_cr_average;
+ /* Check ts validity */
+ if( i_ts_bound != INT64_MAX &&
+ *pi_ts0 > VLC_TS_INVALID && *pi_ts0 >= mdate() + cl->i_pts_delay + i_ts_bound )
+ return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+}
+/*****************************************************************************
+ * input_clock_GetRate: Return current rate
+ *****************************************************************************/
+int input_clock_GetRate( input_clock_t *cl )
+{
+ int i_rate;
+
+ vlc_mutex_lock( &cl->lock );
+ i_rate = cl->i_rate;
+ vlc_mutex_unlock( &cl->lock );
+
+ return i_rate;
+}
+
+int input_clock_GetState( input_clock_t *cl,
+ mtime_t *pi_stream_start, mtime_t *pi_system_start,
+ mtime_t *pi_stream_duration, mtime_t *pi_system_duration )
+{
+ vlc_mutex_lock( &cl->lock );
- cl->last_update = i_mdate;
+ if( !cl->b_has_reference )
+ {
+ vlc_mutex_unlock( &cl->lock );
+ return VLC_EGENERIC;
}
+
+ *pi_stream_start = cl->ref.i_stream;
+ *pi_system_start = cl->ref.i_system;
+
+ *pi_stream_duration = cl->last.i_stream - cl->ref.i_stream;
+ *pi_system_duration = cl->last.i_system - cl->ref.i_system;
+
+ vlc_mutex_unlock( &cl->lock );
+
+ return VLC_SUCCESS;
+}
+
+void input_clock_ChangeSystemOrigin( input_clock_t *cl, mtime_t i_system )
+{
+ vlc_mutex_lock( &cl->lock );
+
+ assert( cl->b_has_reference );
+ const mtime_t i_offset = i_system - cl->ref.i_system;
+
+ cl->ref.i_system += i_offset;
+ cl->last.i_system += i_offset;
+
+ vlc_mutex_unlock( &cl->lock );
+}
+
+#warning "input_clock_SetJitter needs more work"
+void input_clock_SetJitter( input_clock_t *cl,
+ mtime_t i_pts_delay, int i_cr_average )
+{
+ vlc_mutex_lock( &cl->lock );
+
+ /* TODO always save the value, and when rebuffering use the new one if smaller
+ * TODO when increasing -> force rebuffering
+ */
+ if( cl->i_pts_delay < i_pts_delay )
+ cl->i_pts_delay = i_pts_delay;
+
+ /* */
+ if( i_cr_average < 10 )
+ i_cr_average = 10;
+
+ if( cl->drift.i_divider != i_cr_average )
+ AvgRescale( &cl->drift, i_cr_average );
+
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
- * input_ClockResetPCR:
+ * ClockStreamToSystem: converts a movie clock to system date
*****************************************************************************/
-void input_ClockResetPCR( input_thread_t * p_input, input_clock_t *cl )
+static mtime_t ClockStreamToSystem( input_clock_t *cl, mtime_t i_stream )
{
- cl->i_synchro_state = SYNCHRO_REINIT;
- cl->last_pts = 0;
+ if( !cl->b_has_reference )
+ return VLC_TS_INVALID;
+
+ return ( i_stream - cl->ref.i_stream ) * cl->i_rate / INPUT_RATE_DEFAULT +
+ cl->ref.i_system;
}
/*****************************************************************************
- * input_ClockGetTS: manages a PTS or DTS
+ * ClockSystemToStream: converts a system date to movie clock
+ *****************************************************************************
+ * Caution : a valid reference point is needed for this to operate.
*****************************************************************************/
-mtime_t input_ClockGetTS( input_thread_t * p_input,
- input_clock_t *cl, mtime_t i_ts )
+static mtime_t ClockSystemToStream( input_clock_t *cl, mtime_t i_system )
{
- if( cl->i_synchro_state != SYNCHRO_OK )
- return 0;
-
- cl->last_pts = ClockToSysdate( cl, i_ts + cl->delta_cr );
- return cl->last_pts + p_input->i_pts_delay;
+ assert( cl->b_has_reference );
+ return ( i_system - cl->ref.i_system ) * INPUT_RATE_DEFAULT / cl->i_rate +
+ cl->ref.i_stream;
}
/*****************************************************************************
- * input_ClockSetRate:
+ * Long term average helpers
*****************************************************************************/
-void input_ClockSetRate( input_thread_t *p_input, input_clock_t *cl )
+static void AvgInit( average_t *p_avg, int i_divider )
{
- /* Move the reference point */
- if( cl->i_synchro_state == SYNCHRO_OK )
- ClockNewRef( cl, cl->last_cr, cl->last_sysdate );
+ p_avg->i_divider = i_divider;
+ AvgReset( p_avg );
+}
+static void AvgClean( average_t *p_avg )
+{
+ VLC_UNUSED(p_avg);
+}
+static void AvgReset( average_t *p_avg )
+{
+ p_avg->i_value = 0;
+ p_avg->i_residue = 0;
+ p_avg->i_count = 0;
+}
+static void AvgUpdate( average_t *p_avg, mtime_t i_value )
+{
+ const int i_f0 = __MIN( p_avg->i_divider - 1, p_avg->i_count );
+ const int i_f1 = p_avg->i_divider - i_f0;
+
+ const mtime_t i_tmp = i_f0 * p_avg->i_value + i_f1 * i_value + p_avg->i_residue;
+
+ p_avg->i_value = i_tmp / p_avg->i_divider;
+ p_avg->i_residue = i_tmp % p_avg->i_divider;
- cl->i_rate = p_input->p->i_rate;
+ p_avg->i_count++;
}
+static mtime_t AvgGet( average_t *p_avg )
+{
+ return p_avg->i_value;
+}
+static void AvgRescale( average_t *p_avg, int i_divider )
+{
+ const mtime_t i_tmp = p_avg->i_value * p_avg->i_divider + p_avg->i_residue;
+ p_avg->i_divider = i_divider;
+ p_avg->i_value = i_tmp / p_avg->i_divider;
+ p_avg->i_residue = i_tmp % p_avg->i_divider;
+}