Player timer

Collaboration diagram for Player timer:

Data Structures
struct	vlc_player_timer_point
	Player timer point. More...
struct	vlc_player_timer_smpte_timecode
	Player smpte timecode. More...
struct	vlc_player_timer_cbs
	Player timer callbacks. More...
struct	vlc_player_timer_smpte_cbs
	Player smpte timer callbacks. More...

Typedefs
typedef struct vlc_player_timer_id	vlc_player_timer_id
	Player timer opaque structure.

Functions
vlc_player_timer_id *	vlc_player_AddTimer (vlc_player_t *player, vlc_tick_t min_period, const struct vlc_player_timer_cbs *cbs, void *cbs_data)
	Add a timer in order to get times updates.
vlc_player_timer_id *	vlc_player_AddSmpteTimer (vlc_player_t *player, const struct vlc_player_timer_smpte_cbs *cbs, void *cbs_data)
	Add a smpte timer in order to get accurate video frame updates.
void	vlc_player_RemoveTimer (vlc_player_t *player, vlc_player_timer_id *timer)
	Remove a player timer.
int	vlc_player_timer_point_Interpolate (const struct vlc_player_timer_point *point, vlc_tick_t system_now, vlc_tick_t *out_ts, double *out_pos)
	Interpolate the last timer value to now.
vlc_tick_t	vlc_player_timer_point_GetNextIntervalDate (const struct vlc_player_timer_point *point, vlc_tick_t system_now, vlc_tick_t interpolated_ts, vlc_tick_t next_interval)
	Get the date of the next interval.

Detailed Description

Typedef Documentation

vlc_player_timer_id

typedef struct vlc_player_timer_id vlc_player_timer_id

Player timer opaque structure.

Function Documentation

vlc_player_AddSmpteTimer()

vlc_player_timer_id * vlc_player_AddSmpteTimer	(	vlc_player_t *	player,
		const struct vlc_player_timer_smpte_cbs *	cbs,
		void *	cbs_data
	)

Add a smpte timer in order to get accurate video frame updates.

Parameters

player	player instance (locked or not)
cbs	pointer to a vlc_player_timer_smpte_cbs structure, the structure must be valid during the lifetime of the player
cbs_data	opaque pointer used by the callbacks

Returns

a valid vlc_player_timer_id or NULL in case of memory allocation error

References vlc_player_timer_id::cbs, vlc_player_timer_id::data, vlc_player_timer_id::last_update_date, vlc_player_timer::lock, vlc_player_timer_id::node, vlc_player_timer_cbs::on_update, vlc_player_timer_id::period, vlc_player_timer_id::smpte_cbs, vlc_player_t::timer, vlc_list_append(), vlc_mutex_lock(), vlc_mutex_unlock(), and VLC_TICK_INVALID.

vlc_player_AddTimer()

vlc_player_timer_id * vlc_player_AddTimer	(	vlc_player_t *	player,
		vlc_tick_t	min_period,
		const struct vlc_player_timer_cbs *	cbs,
		void *	cbs_data
	)

Add a timer in order to get times updates.

Parameters

player	player instance (locked or not)
min_period	corresponds to the minimum period between each updates, use it to avoid flood from too many source updates, set it to VLC_TICK_INVALID to receive all updates.
cbs	pointer to a vlc_player_timer_cbs structure, the structure must be valid during the lifetime of the player
cbs_data	opaque pointer used by the callbacks

Returns

a valid vlc_player_timer_id or NULL in case of memory allocation error

References vlc_player_timer_id::cbs, vlc_player_timer_id::data, vlc_player_timer_id::last_update_date, vlc_player_timer::lock, vlc_player_timer_id::node, vlc_player_timer_cbs::on_update, vlc_player_timer_id::period, vlc_player_t::timer, vlc_list_append(), vlc_mutex_lock(), vlc_mutex_unlock(), VLC_TICK_0, and VLC_TICK_INVALID.

vlc_player_RemoveTimer()

void vlc_player_RemoveTimer	(	vlc_player_t *	player,
		vlc_player_timer_id *	timer
	)

Remove a player timer.

Parameters

player	player instance (locked or not)
timer	timer created by vlc_player_AddTimer()

References vlc_player_timer::lock, vlc_player_timer_id::node, vlc_player_t::timer, vlc_list_remove(), vlc_mutex_lock(), and vlc_mutex_unlock().

vlc_player_timer_point_GetNextIntervalDate()

vlc_tick_t vlc_player_timer_point_GetNextIntervalDate	(	const struct vlc_player_timer_point *	point,
		vlc_tick_t	system_now,
		vlc_tick_t	interpolated_ts,
		vlc_tick_t	next_interval
	)

Get the date of the next interval.

Can be used to setup an UI timer in order to update some widgets at specific interval. A next_interval of VLC_TICK_FROM_SEC(1) can be used to update a time widget when the media reaches a new second.

Note

The media time doesn't necessarily correspond to the system time, that is why this function is needed and use the rate of the current point.

Parameters

point	time update obtained via the vlc_player_timer_cbs.on_update()
system_now	current system date
interpolated_ts	ts returned by vlc_player_timer_point_Interpolate() with the same system now
next_interval	next interval

Returns

the absolute system date of the next interval

References vlc_player_timer_point::rate, and VLC_TICK_INVALID.

vlc_player_timer_point_Interpolate()

int vlc_player_timer_point_Interpolate	(	const struct vlc_player_timer_point *	point,
		vlc_tick_t	system_now,
		vlc_tick_t *	out_ts,
		double *	out_pos
	)

Interpolate the last timer value to now.

Parameters

point	time update obtained via the vlc_player_timer_cbs.on_update() callback
system_now	current system date
out_ts	pointer where to set the interpolated ts, subtract this time with VLC_TICK_0 to get the original value.
out_pos	pointer where to set the interpolated position

Returns

VLC_SUCCESS in case of success, an error in the interpolated ts is negative (could happen during the buffering step)

References vlc_player_timer_point::length, vlc_player_timer_point::position, vlc_player_timer_point::rate, vlc_player_timer_point::system_date, vlc_player_timer_point::ts, unlikely, VLC_EGENERIC, VLC_SUCCESS, VLC_TICK_0, VLC_TICK_INVALID, and VLC_TICK_MAX.

Referenced by vlc_player_GetTimerPoint().