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 #include "clock.h"
30 
31 /** @struct input_clock_t
32  * This structure is used to manage clock drift and reception jitters
33  *
34  * This API is reentrant but not thread-safe.
35  */
36 typedef struct input_clock_t input_clock_t;
37 
38 /**
39  * This function creates a new input_clock_t.
40  *
41  * You must use input_clock_Delete to delete it once unused.
42  */
44 
45 /**
46  * This function attach a clock listener to the input clock
47  *
48  * It can be called only one time, with a valid clock, before the first update
49  * (input_clock_Update()).
50  *
51  * \param clock_listener clock created with vlc_clock_main_CreateInputMaster().
52  * The input_clock_t will take ownership of this clock and drive the main
53  * clock.
54  */
56 
57 /**
58  * This function destroys a input_clock_t created by input_clock_New.
59  */
61 
62 /**
63  * This function will update a input_clock_t with a new clock reference point.
64  * It will also tell if the clock point is late regarding our buffering.
65  *
66  * \param b_buffering_allowed tells if we are allowed to bufferize more data in
67  * advanced (if possible).
68  * \return clock update delay
69  */
71  bool b_can_pace_control, bool b_buffering_allowed,
72  vlc_tick_t i_clock, vlc_tick_t i_system );
73 /**
74  * This function will reset the drift of a input_clock_t.
75  *
76  * The actual jitter estimation will not be reseted by it.
77  */
79 
80 /**
81  * This functions will return a deadline used to control the reading speed.
82  */
84 
85 /**
86  * This functions allows changing the actual reading speed.
87  */
89 
90 /**
91  * This function allows changing the pause status.
92  */
94 
95 /**
96  * This function returns the original system value date and the delay for the current
97  * reference point (a valid reference point must have been set).
98  */
99 void input_clock_GetSystemOrigin( input_clock_t *, vlc_tick_t *pi_system, vlc_tick_t *pi_delay );
100 
101 /**
102  * This function allows rebasing the original system value date (a valid
103  * reference point must have been set).
104  * When using the absolute mode, it will create a discontinuity unless
105  * called imediatly after a input_clock_Update.
106  */
107 void input_clock_ChangeSystemOrigin( input_clock_t *, bool b_absolute, vlc_tick_t i_system );
108 
109 /**
110  * This function returns the current rate.
111  */
113 
114 /**
115  * This function returns current clock state or VLC_EGENERIC if there is not a
116  * reference point.
117  */
119  vlc_tick_t *pi_stream_start, vlc_tick_t *pi_system_start,
120  vlc_tick_t *pi_stream_duration, vlc_tick_t *pi_system_duration );
121 
122 /**
123  * This function allows the set the minimal configuration for the jitter estimation algo.
124  */
126  vlc_tick_t i_pts_delay, int i_cr_average );
127 
128 /**
129  * This function returns an estimation of the pts_delay needed to avoid rebufferization.
130  * XXX in the current implementation, the pts_delay will never be decreased.
131  */
133 
134 #endif
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:214
input_clock_t * input_clock_New(float rate)
This function creates a new input_clock_t.
Definition: input_clock.c:159
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:391
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:375
void input_clock_AttachListener(input_clock_t *, vlc_clock_t *clock_listener)
This function attach a clock listener to the input clock.
Definition: input_clock.c:200
void input_clock_Reset(input_clock_t *)
This function will reset the drift of a input_clock_t.
Definition: input_clock.c:304
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:333
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:356
void input_clock_Delete(input_clock_t *)
This function destroys a input_clock_t created by input_clock_New.
Definition: input_clock.c:192
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:415
void input_clock_ChangeRate(input_clock_t *, float rate)
This functions allows changing the actual reading speed.
Definition: input_clock.c:317
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:460
float input_clock_GetRate(input_clock_t *)
This function returns the current rate.
Definition: input_clock.c:370
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:425
This structure is used to manage clock drift and reception jitters.
Definition: input_clock.c:103
bool b_paused
Definition: input_clock.c:133
vlc_tick_t i_pts_delay
Definition: input_clock.c:135
vlc_clock_t * clock_listener
Definition: input_clock.c:104
float rate
Definition: input_clock.c:134
Definition: clock.c:65
VLC object common members.
Definition: vlc_objects.h:45
This file is a collection of common definitions and types.
Input thread interface.
int64_t vlc_tick_t
High precision date or time interval.
Definition: vlc_tick.h:45