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https://gitlab.freedesktop.org/gstreamer/gstreamer.git
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88 lines
1.3 KiB
Text
88 lines
1.3 KiB
Text
The clock
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---------
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The clock always returns reference time
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Element State change
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--------------------
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Each element receives the current clock reference time
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in the state change function.
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On PAUSED to PLAYING
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An element starts sending buffers with timestamp
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reftime + internal counter
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After a seek, the element sets internal counters to 0
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Bin state change
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----------------
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PAUSED to PLAYING
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bin propagates clock time to children
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Toplevel bin state change
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-------------------------
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PAUSED to PLAYING
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start time is set to ref time
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stream time is thus 0
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start time is sent to state change of children
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use case 1
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----------
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filesrc ! mad ! osssink
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pipeline PAUSED to PLAYING:
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start time = ref time
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filesrc state change gets starttime
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mad state change gets starttime
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osssink state change gets starttime
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mad sends buffers with timestamp starttime + internal counter
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osssink syncs these samples against the clock with starttime + timestamp
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PLAYING to PAUSED
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nothing happens
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use case 2
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----------
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{ filesrc ! mad ! queue } ! osssink
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let it play for a while
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PAUSE the thread
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PLAY the thread
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thread is not the toplevel bin, use same starttime as when
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it first started.
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do state change on elements with same starttime
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use case 3
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----------
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filesrc ! mad ! mixer ! osssink
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!
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filesrc ! mad !-^
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