doc updates

Original commit message from CVS:
doc updates
This commit is contained in:
Thomas Vander Stichele 2005-11-28 17:59:25 +00:00
parent 870d272630
commit 597335c574

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@ -31,64 +31,64 @@
* base class.
*
* The #GstClock returns a monotonically increasing time with the method
* gst_clock_get_time(). Its accuracy and base time depends on the specific clock
* implementation but time is always expessed in nanoseconds. Since the
* gst_clock_get_time(). Its accuracy and base time depends on the specific
* clock implementation but time is always expessed in nanoseconds. Since the
* baseline of the clock is undefined, the clock time returned is not
* meaningfull in itself, what matters are the deltas between two clock
* times.
* meaningful in itself, what matters are the deltas between two clock times.
*
* The pipeline uses the clock to calculate the stream time.
* Usually all renderers synchronize to the global clock using the buffer timestamps,
* the newsegment events and the element's base time.
* The pipeline uses the clock to calculate the stream time. Usually all
* renderers synchronize to the global clock using the buffer timestamps, the
* newsegment events and the element's base time.
*
* The time of the clock in itself is not very useful for an application.
*
* A clock implementation can support periodic and single shot clock notifications
* both synchronous and asynchronous.
* A clock implementation can support periodic and single shot clock
* notifications both synchronous and asynchronous.
*
* One first needs to create a #GstClockID for the periodic or single shot
* notification using gst_clock_new_single_shot_id() or gst_clock_new_periodic_id().
* notification using gst_clock_new_single_shot_id() or
* gst_clock_new_periodic_id().
*
* To perform a blocking wait for the specific time of the #GstClockID use the
* gst_clock_id_wait(). To receive a callback when the specific time is reached
* in the clock use gst_clock_id_wait_async(). Both these calls can be interrupted
* with the gst_clock_id_unschedule() call. If the blocking wait is unscheduled
* a return value of GST_CLOCK_UNSCHEDULED is returned.
* in the clock use gst_clock_id_wait_async(). Both these calls can be
* interrupted with the gst_clock_id_unschedule() call. If the blocking wait is
* unscheduled a return value of GST_CLOCK_UNSCHEDULED is returned.
*
* Periodic callbacks scheduled async will be repeadedly called automatically until
* it is unscheduled. To schedule an async periodic callback, gst_clock_id_wait()
* should be called repeadedly.
* Periodic callbacks scheduled async will be repeadedly called automatically
* until it is unscheduled. To schedule an async periodic callback,
* gst_clock_id_wait() should be called repeadedly.
*
* The async callbacks can happen from any thread, either provided by the
* core or from a streaming thread. The application should be prepared for this.
* The async callbacks can happen from any thread, either provided by the core
* or from a streaming thread. The application should be prepared for this.
*
* A #GstClockID that has been unscheduled cannot be used again for any wait
* operation.
*
* It is possible to perform a blocking wait on the same #GstClockID from multiple
* threads. However, registering the same #GstClockID for multiple async notifications is
* not possible, the callback will only be called once.
* It is possible to perform a blocking wait on the same #GstClockID from
* multiple threads. However, registering the same #GstClockID for multiple
* async notifications is not possible, the callback will only be called once.
*
* None of the wait operations unref the #GstClockID, the owner is
* responsible for unreffing the ids itself. This holds for both periodic and
* single shot notifications. The reason being that the owner of the #GstClockID
* has to keep a handle to the #GstClockID to unblock the wait on FLUSHING events
* or state changes and if we unref it automatically, the handle might be
* invalid.
* None of the wait operations unref the #GstClockID, the owner is responsible
* for unreffing the ids itself. This holds for both periodic and single shot
* notifications. The reason being that the owner of the #GstClockID has to
* keep a handle to the #GstClockID to unblock the wait on FLUSHING events or
* state changes and if we unref it automatically, the handle might be invalid.
*
* These clock operations do not operate on the stream time, so the callbacks
* will also occur when not in PLAYING state as if the clock just keeps on
* running. Some clocks however do not progress when the element that provided
* the clock is not PLAYING.
*
* When a clock has the GST_CLOCK_FLAG_CAN_SET_MASTER flag set, it can be slaved to
* another #GstClock with the gst_clock_set_master(). The clock will then
* automatically be synchronized to this master clock by repeadedly sampling the
* master clock and the slave clock and recalibrating the slave clock with
* gst_clock_set_calibration(). This feature is mostly usefull for plugins that have
* an internal clock but must operate with another clock selected by the #GstPipeline.
* They can track the offset and rate difference of their internal clock relative to
* the master clock by using the gst_clock_get_calibration() function.
* When a clock has the GST_CLOCK_FLAG_CAN_SET_MASTER flag set, it can be
* slaved to another #GstClock with the gst_clock_set_master(). The clock will
* then automatically be synchronized to this master clock by repeadedly
* sampling the master clock and the slave clock and recalibrating the slave
* clock with gst_clock_set_calibration(). This feature is mostly usefull for
* plugins that have an internal clock but must operate with another clock
* selected by the #GstPipeline. They can track the offset and rate difference
* of their internal clock relative to the master clock by using the
* gst_clock_get_calibration() function.
*
* Last reviewed on 2005-10-28 (0.9.4)
*/
@ -118,7 +118,7 @@ static GstAllocTrace *_gst_clock_entry_trace;
#define DEFAULT_STATS FALSE
#define DEFAULT_WINDOW_SIZE 32
#define DEFAULT_WINDOW_THRESHOLD 4
#define DEFAULT_TIMEOUT GST_SECOND / 10
#define DEFAULT_TIMEOUT GST_SECOND / 10
enum
{