1 /*****************************************************************************
2 * clock.h: clocks synchronisation
3 *****************************************************************************
4 * Copyright (C) 2008 the VideoLAN team
5 * Copyright (C) 2008 Laurent Aimar
8 * Authors: Laurent Aimar < fenrir _AT_ videolan _DOT_ org >
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
25 #ifndef LIBVLC_INPUT_CLOCK_H
26 #define LIBVLC_INPUT_CLOCK_H 1
28 #include <vlc_common.h>
29 #include <vlc_input.h> /* FIXME Needed for input_clock_t */
31 /** @struct input_clock_t
32 * This structure is used to manage clock drift and reception jitters
34 * XXX input_clock_GetTS can be called from any threads. All others functions
35 * MUST be called from one and only one thread.
39 * This function creates a new input_clock_t.
40 * You must use input_clock_Delete to delete it once unused.
42 input_clock_t *input_clock_New( int i_rate );
45 * This function destroys a input_clock_t created by input_clock_New.
47 void input_clock_Delete( input_clock_t * );
50 * This function will update a input_clock_t with a new clock reference point.
51 * It will also tell if the clock point is late regarding our buffering.
53 * \param b_buffering_allowed tells if we are allowed to bufferize more data in
54 * advanced (if possible).
56 void input_clock_Update( input_clock_t *, vlc_object_t *p_log,
58 bool b_can_pace_control, bool b_buffering_allowed,
59 mtime_t i_clock, mtime_t i_system );
61 * This function will reset the drift of a input_clock_t.
63 * The actual jitter estimation will not be reseted by it.
65 void input_clock_Reset( input_clock_t * );
68 * This functions will return a deadline used to control the reading speed.
70 mtime_t input_clock_GetWakeup( input_clock_t * );
73 * This functions allows to change the actual reading speed.
75 void input_clock_ChangeRate( input_clock_t *, int i_rate );
78 * This function allows to change the pause status.
80 void input_clock_ChangePause( input_clock_t *, bool b_paused, mtime_t i_date );
83 * This function returns the original system value date and the delay for the current
84 * reference point (a valid reference point must have been set).
86 void input_clock_GetSystemOrigin( input_clock_t *, mtime_t *pi_system, mtime_t *pi_delay );
89 * This function allows to rebase the original system value date (a valid
90 * reference point must have been set).
91 * When using the absolute mode, it will create a discontinuity unless
92 * called imediatly after a input_clock_Update.
94 void input_clock_ChangeSystemOrigin( input_clock_t *, bool b_absolute, mtime_t i_system );
97 * This function converts a pair of timestamp from stream clock to system clock.
99 * If pi_rate is provided it will be filled with the rate value used for
101 * p_ts0 is a pointer to a timestamp to be converted (in place) and must be non NULL.
102 * p_ts1 is a pointer to a timestamp to be converted (in place) and can be NULL.
104 * It will return VLC_EGENERIC if i_ts_bound is not INT64_MAX and if the value *p_ts0
105 * after conversion is not before the deadline mdate() + i_pts_delay + i_ts_bound.
106 * It will also return VLC_EGENERIC if the conversion cannot be done successfully. In
107 * this case, *p_ts0 and *p_ts1 will hold an invalid timestamp.
108 * Otherwise it will return VLC_SUCCESS.
110 int input_clock_ConvertTS( input_clock_t *, int *pi_rate, mtime_t *pi_ts0, mtime_t *pi_ts1, mtime_t i_ts_bound );
113 * This function returns the current rate.
115 int input_clock_GetRate( input_clock_t * );
118 * This function returns current clock state or VLC_EGENERIC if there is not a
121 int input_clock_GetState( input_clock_t *,
122 mtime_t *pi_stream_start, mtime_t *pi_system_start,
123 mtime_t *pi_stream_duration, mtime_t *pi_system_duration );
126 * This function allows the set the minimal configuration for the jitter estimation algo.
128 void input_clock_SetJitter( input_clock_t *,
129 mtime_t i_pts_delay, int i_cr_average );
132 * This function returns an estimation of the pts_delay needed to avoid rebufferization.
133 * XXX in the current implementation, the pts_delay will never be decreased.
135 mtime_t input_clock_GetJitter( input_clock_t * );