VLC  4.0.0-dev
input_clock.h
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1 /*****************************************************************************
2  * input_clock.h: Input clocks synchronisation
3  *****************************************************************************
4  * Copyright (C) 2008-2018 VLC authors and VideoLAN
5  * Copyright (C) 2008 Laurent Aimar
6  *
7  * Authors: Laurent Aimar < fenrir _AT_ videolan _DOT_ org >
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU Lesser General Public License as published by
11  * the Free Software Foundation; either version 2.1 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  * GNU Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public License
20  * along with this program; if not, write to the Free Software Foundation,
21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22  *****************************************************************************/
23 
24 #ifndef LIBVLC_INPUT_CLOCK_H
25 #define LIBVLC_INPUT_CLOCK_H 1
26 
27 #include <vlc_common.h>
28 #include <vlc_input.h> /* FIXME Needed for input_clock_t */
29 
30 /** @struct input_clock_t
31  * This structure is used to manage clock drift and reception jitters
32  *
33  * This API is reentrant but not thread-safe.
34  */
36 
37 /**
38  * This function creates a new input_clock_t.
39  * You must use input_clock_Delete to delete it once unused.
40  */
42 
43 /**
44  * This function destroys a input_clock_t created by input_clock_New.
45  */
47 
48 /**
49  * This function will update a input_clock_t with a new clock reference point.
50  * It will also tell if the clock point is late regarding our buffering.
51  *
52  * \param b_buffering_allowed tells if we are allowed to bufferize more data in
53  * advanced (if possible).
54  * \return clock update delay
55  */
57  bool b_can_pace_control, bool b_buffering_allowed,
58  vlc_tick_t i_clock, vlc_tick_t i_system );
59 /**
60  * This function will reset the drift of a input_clock_t.
61  *
62  * The actual jitter estimation will not be reseted by it.
63  */
65 
66 /**
67  * This functions will return a deadline used to control the reading speed.
68  */
70 
71 /**
72  * This functions allows changing the actual reading speed.
73  */
75 
76 /**
77  * This function allows changing the pause status.
78  */
80 
81 /**
82  * This function returns the original system value date and the delay for the current
83  * reference point (a valid reference point must have been set).
84  */
85 void input_clock_GetSystemOrigin( input_clock_t *, vlc_tick_t *pi_system, vlc_tick_t *pi_delay );
86 
87 /**
88  * This function allows rebasing the original system value date (a valid
89  * reference point must have been set).
90  * When using the absolute mode, it will create a discontinuity unless
91  * called imediatly after a input_clock_Update.
92  */
93 void input_clock_ChangeSystemOrigin( input_clock_t *, bool b_absolute, vlc_tick_t i_system );
94 
95 /**
96  * This function returns the current rate.
97  */
99 
100 /**
101  * This function returns current clock state or VLC_EGENERIC if there is not a
102  * reference point.
103  */
105  vlc_tick_t *pi_stream_start, vlc_tick_t *pi_system_start,
106  vlc_tick_t *pi_stream_duration, vlc_tick_t *pi_system_duration );
107 
108 /**
109  * This function allows the set the minimal configuration for the jitter estimation algo.
110  */
112  vlc_tick_t i_pts_delay, int i_cr_average );
113 
114 /**
115  * This function returns an estimation of the pts_delay needed to avoid rebufferization.
116  * XXX in the current implementation, the pts_delay will never be decreased.
117  */
119 
120 #endif
input_clock_GetState
int input_clock_GetState(input_clock_t *cl, vlc_tick_t *pi_stream_start, vlc_tick_t *pi_system_start, vlc_tick_t *pi_stream_duration, vlc_tick_t *pi_system_duration)
This function returns current clock state or VLC_EGENERIC if there is not a reference point.
Definition: input_clock.c:344
ClockGetTsOffset
static vlc_tick_t ClockGetTsOffset(input_clock_t *)
It returns timestamp display offset due to ref/last modfied on rate changes It ensures that currently...
Definition: input_clock.c:471
input_clock_t::pi_value
vlc_tick_t pi_value[(3)]
Definition: input_clock.c:121
clock_point_t::stream
vlc_tick_t stream
Definition: clock_internal.h:58
input_clock_t::rate
float rate
Definition: input_clock.c:135
average_t
This structure holds long term moving average.
Definition: clock_internal.h:36
clock_internal.h
input_clock_t::i_external_clock
vlc_tick_t i_external_clock
Definition: input_clock.c:130
vlc_common.h
input_clock_ChangeSystemOrigin
void input_clock_ChangeSystemOrigin(input_clock_t *, bool b_absolute, vlc_tick_t i_system)
This function allows rebasing the original system value date (a valid reference point must have been ...
Definition: input_clock.c:360
input_clock_t
Definition: input_clock.c:105
clock_point_Create
static clock_point_t clock_point_Create(vlc_tick_t system, vlc_tick_t stream)
Definition: clock_internal.h:61
INPUT_CLOCK_LATE_COUNT
#define INPUT_CLOCK_LATE_COUNT
Definition: input_clock.c:102
input_clock_GetSystemOrigin
void input_clock_GetSystemOrigin(input_clock_t *cl, vlc_tick_t *pi_system, vlc_tick_t *pi_delay)
This function returns the original system value date and the delay for the current reference point (a...
Definition: input_clock.c:382
input_clock_GetRate
float input_clock_GetRate(input_clock_t *)
This function returns the current rate.
Definition: input_clock.c:339
AvgUpdate
void AvgUpdate(average_t *avg, double value)
Definition: clock_internal.c:50
AvgReset
void AvgReset(average_t *avg)
Definition: clock_internal.c:44
input_clock_t::i_next_drift_update
vlc_tick_t i_next_drift_update
Definition: input_clock.c:115
input_clock_Update
vlc_tick_t input_clock_Update(input_clock_t *, vlc_object_t *p_log, bool b_can_pace_control, bool b_buffering_allowed, vlc_tick_t i_clock, vlc_tick_t i_system)
This function will update a input_clock_t with a new clock reference point.
Definition: input_clock.c:192
clock_point_t
Definition: clock_internal.h:55
input_clock_ChangePause
void input_clock_ChangePause(input_clock_t *cl, bool b_paused, vlc_tick_t i_date)
This function allows changing the pause status.
Definition: input_clock.c:304
VLC_EGENERIC
#define VLC_EGENERIC
Unspecified error.
Definition: vlc_common.h:474
ClockSystemToStream
static vlc_tick_t ClockSystemToStream(input_clock_t *, vlc_tick_t i_system)
Definition: input_clock.c:461
input_clock_GetWakeup
vlc_tick_t input_clock_GetWakeup(input_clock_t *)
This functions will return a deadline used to control the reading speed.
Definition: input_clock.c:325
vlc_input.h
clock_point_t::system
vlc_tick_t system
Definition: clock_internal.h:57
input_clock.h
input_clock_t::b_has_external_clock
bool b_has_external_clock
Definition: input_clock.c:131
input_clock_t::i_index
unsigned i_index
Definition: input_clock.c:122
AvgClean
void AvgClean(average_t *avg)
Definition: clock_internal.c:39
input_clock_GetSystemOrigin
void input_clock_GetSystemOrigin(input_clock_t *, vlc_tick_t *pi_system, vlc_tick_t *pi_delay)
This function returns the original system value date and the delay for the current reference point (a...
Definition: input_clock.c:382
input_clock_t::b_paused
bool b_paused
Definition: input_clock.c:134
msg_Warn
#define msg_Warn(p_this,...)
Definition: vlc_messages.h:104
input_clock_t::i_buffering_duration
vlc_tick_t i_buffering_duration
Definition: input_clock.c:112
CR_MEAN_PTS_GAP
#define CR_MEAN_PTS_GAP
Definition: input_clock.c:86
input_clock_SetJitter
void input_clock_SetJitter(input_clock_t *cl, vlc_tick_t i_pts_delay, int i_cr_average)
This function allows the set the minimal configuration for the jitter estimation algo.
Definition: input_clock.c:392
input_clock_GetWakeup
vlc_tick_t input_clock_GetWakeup(input_clock_t *cl)
This functions will return a deadline used to control the reading speed.
Definition: input_clock.c:325
vlc_tick_t
int64_t vlc_tick_t
High precision date or time interval.
Definition: vlc_tick.h:45
input_clock_t::b_has_reference
bool b_has_reference
Definition: input_clock.c:127
CR_MAX_GAP
#define CR_MAX_GAP
Definition: input_clock.c:82
AvgInit
void AvgInit(average_t *avg, int range)
Definition: clock_internal.c:33
VLC_TICK_INVALID
#define VLC_TICK_INVALID
Definition: vlc_config.h:44
input_clock_Update
vlc_tick_t input_clock_Update(input_clock_t *cl, vlc_object_t *p_log, bool b_can_pace_control, bool b_buffering_allowed, vlc_tick_t i_ck_stream, vlc_tick_t i_ck_system)
This function will update a input_clock_t with a new clock reference point.
Definition: input_clock.c:192
input_clock_GetRate
float input_clock_GetRate(input_clock_t *cl)
This function returns the current rate.
Definition: input_clock.c:339
input_clock_GetJitter
vlc_tick_t input_clock_GetJitter(input_clock_t *cl)
This function returns an estimation of the pts_delay needed to avoid rebufferization.
Definition: input_clock.c:427
input_clock_t::i_pause_date
vlc_tick_t i_pause_date
Definition: input_clock.c:137
input_clock_New
input_clock_t * input_clock_New(float rate)
This function creates a new input_clock_t.
Definition: input_clock.c:148
input_clock_GetState
int input_clock_GetState(input_clock_t *, vlc_tick_t *pi_stream_start, vlc_tick_t *pi_system_start, vlc_tick_t *pi_stream_duration, vlc_tick_t *pi_system_duration)
This function returns current clock state or VLC_EGENERIC if there is not a reference point.
Definition: input_clock.c:344
AvgGet
double AvgGet(average_t *avg)
Definition: clock_internal.c:70
input_clock_ChangeSystemOrigin
void input_clock_ChangeSystemOrigin(input_clock_t *cl, bool b_absolute, vlc_tick_t i_system)
This function allows rebasing the original system value date (a valid reference point must have been ...
Definition: input_clock.c:360
input_clock_Delete
void input_clock_Delete(input_clock_t *)
This function destroys a input_clock_t created by input_clock_New.
Definition: input_clock.c:180
input_clock_SetJitter
void input_clock_SetJitter(input_clock_t *, vlc_tick_t i_pts_delay, int i_cr_average)
This function allows the set the minimal configuration for the jitter estimation algo.
Definition: input_clock.c:392
AvgRescale
void AvgRescale(average_t *avg, int range)
Definition: clock_internal.c:75
CR_BUFFERING_RATE
#define CR_BUFFERING_RATE
Definition: input_clock.c:91
vlc_object_t
VLC object common members.
Definition: vlc_objects.h:43
input_clock_ChangeRate
void input_clock_ChangeRate(input_clock_t *, float rate)
This functions allows changing the actual reading speed.
Definition: input_clock.c:290
VLC_SUCCESS
#define VLC_SUCCESS
No error.
Definition: vlc_common.h:472
input_clock_ChangePause
void input_clock_ChangePause(input_clock_t *, bool b_paused, vlc_tick_t i_date)
This function allows changing the pause status.
Definition: input_clock.c:304
VLC_TICK_FROM_MS
#define VLC_TICK_FROM_MS(ms)
Definition: vlc_tick.h:122
CR_BUFFERING_TARGET
#define CR_BUFFERING_TARGET
Definition: input_clock.c:99
ClockStreamToSystem
static vlc_tick_t ClockStreamToSystem(input_clock_t *, vlc_tick_t i_stream)
Definition: input_clock.c:448
input_clock_t::last
clock_point_t last
Definition: input_clock.c:109
input_clock_Reset
void input_clock_Reset(input_clock_t *cl)
This function will reset the drift of a input_clock_t.
Definition: input_clock.c:280
input_clock_Delete
void input_clock_Delete(input_clock_t *cl)
This function destroys a input_clock_t created by input_clock_New.
Definition: input_clock.c:180
input_clock_GetJitter
vlc_tick_t input_clock_GetJitter(input_clock_t *)
This function returns an estimation of the pts_delay needed to avoid rebufferization.
Definition: input_clock.c:427
average_t::range
int range
Definition: clock_internal.h:63
input_clock_t::i_pts_delay
vlc_tick_t i_pts_delay
Definition: input_clock.c:136
input_clock_t::late
struct input_clock_t::@9 late
input_clock_ChangeRate
void input_clock_ChangeRate(input_clock_t *cl, float rate)
This functions allows changing the actual reading speed.
Definition: input_clock.c:290
input_clock_t::ref
clock_point_t ref
Definition: input_clock.c:126
input_clock_New
input_clock_t * input_clock_New(float rate)
This function creates a new input_clock_t.
Definition: input_clock.c:148
p
#define p(t)
input_clock_t::drift
average_t drift
Definition: input_clock.c:116
input_clock_Reset
void input_clock_Reset(input_clock_t *)
This function will reset the drift of a input_clock_t.
Definition: input_clock.c:280