/*****************************************************************************
- * input_clock.c: Clock/System date convertions, stream management
+ * clock.c: Clock/System date convertions, stream management
*****************************************************************************
* Copyright (C) 1999-2008 the VideoLAN team
* Copyright (C) 2008 Laurent Aimar
#include <vlc_common.h>
#include <vlc_input.h>
-#include "input_clock.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)
*/
+
/*****************************************************************************
* Constants
*****************************************************************************/
* my dice --Meuuh */
#define CR_MEAN_PTS_GAP (300000)
+/* Rate (in 1/256) at which we will read faster to try to increase our
+ * internal buffer (if we control the pace of the source).
+ */
+#define CR_BUFFERING_RATE (48)
+
+/* Extra internal buffer value (in CLOCK_FREQ)
+ * It is 60s max, remember as it is limited by the size it takes by es_out.c
+ * it can be really large.
+ */
+//#define CR_BUFFERING_TARGET (60000000)
+/* Due to some problems in es_out, we cannot use a large value yet */
+#define CR_BUFFERING_TARGET (100000)
+
/*****************************************************************************
* Structures
*****************************************************************************/
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
return p;
}
+/* */
+#define INPUT_CLOCK_LATE_COUNT (3)
+
/* */
struct input_clock_t
{
- /* Reference point */
- bool b_has_reference;
- clock_point_t ref;
+ /* */
+ vlc_mutex_t lock;
/* Last point
* It is used to detect unexpected stream discontinuities */
clock_point_t last;
- /* Maximal timestamp returned by input_clock_GetTS (in system unit) */
+ /* Maximal timestamp returned by input_clock_ConvertTS (in system unit) */
mtime_t i_ts_max;
+ /* Amount of extra buffering expressed in stream clock */
+ mtime_t i_buffering_duration;
+
/* Clock drift */
mtime_t i_next_drift_update;
average_t drift;
+ /* Late statistics */
+ struct
+ {
+ mtime_t pi_value[INPUT_CLOCK_LATE_COUNT];
+ unsigned i_index;
+ } late;
+
+ /* Reference point */
+ clock_point_t ref;
+ bool b_has_reference;
+
+ /* External clock drift */
+ mtime_t i_external_clock;
+ bool b_has_external_clock;
+
/* Current modifiers */
+ bool b_paused;
int i_rate;
+ mtime_t i_pts_delay;
+ 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 );
+static mtime_t ClockGetTsOffset( input_clock_t * );
+
/*****************************************************************************
* input_clock_New: create a new clock
*****************************************************************************/
-input_clock_t *input_clock_New( int i_cr_average, int i_rate )
+input_clock_t *input_clock_New( int i_rate )
{
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( 0, 0 );
+ cl->ref = clock_point_Create( VLC_TS_INVALID, VLC_TS_INVALID );
+ cl->b_has_external_clock = false;
- cl->last = clock_point_Create( 0, 0 );
+ cl->last = clock_point_Create( VLC_TS_INVALID, VLC_TS_INVALID );
- cl->i_ts_max = 0;
+ cl->i_ts_max = VLC_TS_INVALID;
- cl->i_next_drift_update = 0;
- AvgInit( &cl->drift, i_cr_average );
+ cl->i_buffering_duration = 0;
+
+ cl->i_next_drift_update = VLC_TS_INVALID;
+ AvgInit( &cl->drift, 10 );
+
+ cl->late.i_index = 0;
+ for( int i = 0; i < INPUT_CLOCK_LATE_COUNT; i++ )
+ cl->late.pi_value[i] = 0;
cl->i_rate = i_rate;
+ cl->i_pts_delay = 0;
+ cl->b_paused = false;
+ cl->i_pause_date = VLC_TS_INVALID;
return cl;
}
void input_clock_Delete( input_clock_t *cl )
{
AvgClean( &cl->drift );
+ vlc_mutex_destroy( &cl->lock );
free( cl );
}
* i_ck_stream: date in stream clock
* i_ck_system: date in system clock
*****************************************************************************/
-void input_clock_Update( input_clock_t *cl,
- vlc_object_t *p_log, bool b_can_pace_control,
+void input_clock_Update( input_clock_t *cl, vlc_object_t *p_log,
+ bool *pb_late,
+ bool b_can_pace_control, bool b_buffering_allowed,
mtime_t i_ck_stream, mtime_t i_ck_system )
{
bool b_reset_reference = false;
- if( ( !cl->b_has_reference ) ||
- ( i_ck_stream == 0 && cl->last.i_stream != 0 ) )
+ 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 != 0 &&
+ 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 ) )
{
* warning from the stream control facilities (dd-edited
* stream ?). */
msg_Warn( p_log, "clock gap, unexpected stream discontinuity" );
- cl->i_ts_max = 0;
+ 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 = 0;
+ 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 ) );
+ cl->b_has_external_clock = false;
}
+ /* Compute the drift between the stream clock and the system clock
+ * when we don't control the source pace */
if( !b_can_pace_control && cl->i_next_drift_update < i_ck_system )
{
const mtime_t i_converted = ClockSystemToStream( cl, i_ck_system );
cl->i_next_drift_update = i_ck_system + CLOCK_FREQ/5; /* FIXME why that */
}
+
+ /* Update the extra buffering value */
+ if( !b_can_pace_control || b_reset_reference )
+ {
+ cl->i_buffering_duration = 0;
+ }
+ else if( b_buffering_allowed )
+ {
+ /* Try to bufferize more than necessary by reading
+ * CR_BUFFERING_RATE/256 faster until we have CR_BUFFERING_TARGET.
+ */
+ const mtime_t i_duration = __MAX( i_ck_stream - cl->last.i_stream, 0 );
+
+ cl->i_buffering_duration += ( i_duration * CR_BUFFERING_RATE + 255 ) / 256;
+ if( cl->i_buffering_duration > CR_BUFFERING_TARGET )
+ cl->i_buffering_duration = CR_BUFFERING_TARGET;
+ }
+ //fprintf( stderr, "input_clock_Update: %d :: %lld\n", b_buffering_allowed, cl->i_buffering_duration/1000 );
+
+ /* */
cl->last = clock_point_Create( i_ck_stream, i_ck_system );
+
+ /* It does not take the decoder latency into account but it is not really
+ * the goal of the clock here */
+ const mtime_t i_system_expected = ClockStreamToSystem( cl, i_ck_stream + AvgGet( &cl->drift ) );
+ const mtime_t i_late = ( i_ck_system - cl->i_pts_delay ) - i_system_expected;
+ *pb_late = i_late > 0;
+ if( i_late > 0 )
+ {
+ cl->late.pi_value[cl->late.i_index] = i_late;
+ cl->late.i_index = ( cl->late.i_index + 1 ) % INPUT_CLOCK_LATE_COUNT;
+ }
+
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
*****************************************************************************/
void input_clock_Reset( input_clock_t *cl )
{
+ vlc_mutex_lock( &cl->lock );
+
cl->b_has_reference = false;
- cl->ref = clock_point_Create( 0, 0 );
- cl->i_ts_max = 0;
+ cl->ref = clock_point_Create( VLC_TS_INVALID, VLC_TS_INVALID );
+ cl->b_has_external_clock = false;
+ cl->i_ts_max = VLC_TS_INVALID;
+
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
*****************************************************************************/
void input_clock_ChangeRate( input_clock_t *cl, int i_rate )
{
- /* Move the reference point */
- if( cl->b_has_reference )
- cl->ref = cl->last;
+ vlc_mutex_lock( &cl->lock );
+ if( cl->b_has_reference )
+ {
+ /* Move the reference point (as if we were playing at the new rate
+ * from the start */
+ cl->ref.i_system = cl->last.i_system - (cl->last.i_system - cl->ref.i_system) * i_rate / cl->i_rate;
+ }
cl->i_rate = i_rate;
+
+ vlc_mutex_unlock( &cl->lock );
+}
+
+/*****************************************************************************
+ * input_clock_ChangePause:
+ *****************************************************************************/
+void input_clock_ChangePause( input_clock_t *cl, bool b_paused, mtime_t i_date )
+{
+ vlc_mutex_lock( &cl->lock );
+ assert( (!cl->b_paused) != (!b_paused) );
+
+ if( cl->b_paused )
+ {
+ const mtime_t i_duration = i_date - cl->i_pause_date;
+
+ if( cl->b_has_reference && i_duration > 0 )
+ {
+ cl->ref.i_system += i_duration;
+ cl->last.i_system += i_duration;
+ }
+ }
+ cl->i_pause_date = i_date;
+ cl->b_paused = b_paused;
+
+ vlc_mutex_unlock( &cl->lock );
}
/*****************************************************************************
*****************************************************************************/
mtime_t input_clock_GetWakeup( input_clock_t *cl )
{
- /* Not synchronized, we cannot wait */
+ 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 + AvgGet( &cl->drift ) - cl->i_buffering_duration );
+
+ 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 )
+{
+ assert( pi_ts0 );
+ vlc_mutex_lock( &cl->lock );
+
+ if( pi_rate )
+ *pi_rate = cl->i_rate;
+
if( !cl->b_has_reference )
- return 0;
+ {
+ vlc_mutex_unlock( &cl->lock );
+ *pi_ts0 = VLC_TS_INVALID;
+ if( pi_ts1 )
+ *pi_ts1 = VLC_TS_INVALID;
+ return VLC_EGENERIC;
+ }
/* */
- return ClockStreamToSystem( cl, cl->last.i_stream );
-}
+ const mtime_t i_ts_buffering = cl->i_buffering_duration * cl->i_rate / INPUT_RATE_DEFAULT;
+ const mtime_t i_ts_delay = cl->i_pts_delay + ClockGetTsOffset( cl );
+ /* */
+ if( *pi_ts0 > VLC_TS_INVALID )
+ {
+ *pi_ts0 = ClockStreamToSystem( cl, *pi_ts0 + AvgGet( &cl->drift ) );
+ if( *pi_ts0 > cl->i_ts_max )
+ cl->i_ts_max = *pi_ts0;
+ *pi_ts0 += i_ts_delay;
+ }
+
+ /* XXX we do not ipdate i_ts_max on purpose */
+ if( pi_ts1 && *pi_ts1 > VLC_TS_INVALID )
+ {
+ *pi_ts1 = ClockStreamToSystem( cl, *pi_ts1 + AvgGet( &cl->drift ) ) +
+ i_ts_delay;
+ }
+
+ vlc_mutex_unlock( &cl->lock );
+
+ /* Check ts validity */
+ if( i_ts_bound != INT64_MAX &&
+ *pi_ts0 > VLC_TS_INVALID && *pi_ts0 >= mdate() + i_ts_delay + i_ts_buffering + i_ts_bound )
+ return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+}
/*****************************************************************************
- * input_clock_GetTS: manages a PTS or DTS
+ * input_clock_GetRate: Return current rate
*****************************************************************************/
-mtime_t input_clock_GetTS( input_clock_t *cl,
- mtime_t i_pts_delay, mtime_t i_ts )
+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 )
{
- mtime_t i_converted_ts;
+ vlc_mutex_lock( &cl->lock );
if( !cl->b_has_reference )
- return 0;
+ {
+ 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, bool b_absolute, mtime_t i_system )
+{
+ vlc_mutex_lock( &cl->lock );
+
+ assert( cl->b_has_reference );
+ mtime_t i_offset;
+ if( b_absolute )
+ {
+ i_offset = i_system - cl->ref.i_system - ClockGetTsOffset( cl );
+ }
+ else
+ {
+ if( !cl->b_has_external_clock )
+ {
+ cl->b_has_external_clock = true;
+ cl->i_external_clock = i_system;
+ }
+ i_offset = i_system - cl->i_external_clock;
+ }
+
+ cl->ref.i_system += i_offset;
+ cl->last.i_system += i_offset;
+
+ vlc_mutex_unlock( &cl->lock );
+}
+
+void input_clock_GetSystemOrigin( input_clock_t *cl, mtime_t *pi_system, mtime_t *pi_delay )
+{
+ vlc_mutex_lock( &cl->lock );
+
+ assert( cl->b_has_reference );
+
+ *pi_system = cl->ref.i_system;
+ if( pi_delay )
+ *pi_delay = cl->i_pts_delay;
+
+ 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 );
+
+ /* Update late observations */
+ const mtime_t i_delay_delta = i_pts_delay - cl->i_pts_delay;
+ mtime_t pi_late[INPUT_CLOCK_LATE_COUNT];
+ for( int i = 0; i < INPUT_CLOCK_LATE_COUNT; i++ )
+ pi_late[i] = __MAX( cl->late.pi_value[(cl->late.i_index + 1 + i)%INPUT_CLOCK_LATE_COUNT] - i_delay_delta, 0 );
+
+ for( int i = 0; i < INPUT_CLOCK_LATE_COUNT; i++ )
+ cl->late.pi_value[i] = 0;
+ cl->late.i_index = 0;
+
+ for( int i = 0; i < INPUT_CLOCK_LATE_COUNT; i++ )
+ {
+ if( pi_late[i] <= 0 )
+ continue;
+ cl->late.pi_value[cl->late.i_index] = pi_late[i];
+ cl->late.i_index = ( cl->late.i_index + 1 ) % INPUT_CLOCK_LATE_COUNT;
+ }
+
+ /* 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;
/* */
- i_converted_ts = ClockStreamToSystem( cl, i_ts + AvgGet( &cl->drift ) );
- if( i_converted_ts > cl->i_ts_max )
- cl->i_ts_max = i_converted_ts;
+ if( i_cr_average < 10 )
+ i_cr_average = 10;
+
+ if( cl->drift.i_divider != i_cr_average )
+ AvgRescale( &cl->drift, i_cr_average );
- return i_converted_ts + i_pts_delay;
+ vlc_mutex_unlock( &cl->lock );
+}
+
+mtime_t input_clock_GetJitter( input_clock_t *cl )
+{
+ vlc_mutex_lock( &cl->lock );
+
+#if INPUT_CLOCK_LATE_COUNT != 3
+# error "unsupported INPUT_CLOCK_LATE_COUNT"
+#endif
+ /* Find the median of the last late values
+ * It works pretty well at rejecting bad values
+ *
+ * XXX we only increase pts_delay over time, decreasing it is
+ * not that easy if we want to be robust.
+ */
+ const mtime_t *p = cl->late.pi_value;
+ mtime_t i_late_median = p[0] + p[1] + p[2] - __MIN(__MIN(p[0],p[1]),p[2]) - __MAX(__MAX(p[0],p[1]),p[2]);
+ mtime_t i_pts_delay = cl->i_pts_delay ;
+
+ vlc_mutex_unlock( &cl->lock );
+
+ return i_pts_delay + i_late_median;
}
/*****************************************************************************
static mtime_t ClockStreamToSystem( input_clock_t *cl, mtime_t i_stream )
{
if( !cl->b_has_reference )
- return 0;
+ return VLC_TS_INVALID;
return ( i_stream - cl->ref.i_stream ) * cl->i_rate / INPUT_RATE_DEFAULT +
cl->ref.i_system;
cl->ref.i_stream;
}
+/**
+ * It returns timestamp display offset due to ref/last modfied on rate changes
+ * It ensures that currently converted dates are not changed.
+ */
+static mtime_t ClockGetTsOffset( input_clock_t *cl )
+{
+ return cl->i_pts_delay * ( cl->i_rate - INPUT_RATE_DEFAULT ) / INPUT_RATE_DEFAULT;
+}
+
/*****************************************************************************
* Long term average helpers
*****************************************************************************/
{
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;
+}