View source for GStreamer Daemon - Flush start/Flush stop

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This wiki shows how to send a flush event to a given pipeline. Sometimes it is important to flush a current pipeline and then restart the flushing pipeline.  

== Sending an flush start event ==

Elements should unlock functions when some function is blocked once the event is received with a success code.
This event flush all queued data in the pipeline for new media play.

A new flush start event is sent to a pipeline using the command shown below.
 <b>event_flush_start <i>pipeline</i> </b>
        Creates a new flush start event and sends it to <i>pipeline</i>.

== Sending an flush stop event ==

Allocate a new flush stop event. This event should send after a flush start event, to able the pad and receives data.  
When this event is completed sends a seek and resume dataflow. 

A new flush stop event is sent to a pipeline using the command shown below.
 <b>event_flush_stop <i>pipeline</i> <i>reset&#61;true</i> </b>
        Creates a new flush stop event and sends it to <i>pipeline</i>.


For example:
<br>&rArr; ''Gstd Commands:''
<syntaxhighlight lang="bash" line="line" style="background-color:lavender">
pipeline_create p1 videotestsrc ! autovideosink
pipeline_play p1
event_flush_start p1 
event_flush_stop p1 true 
pipeline_stop p1
pipeline_play p1
</syntaxhighlight>
will respectively
# Create a pipeline ''p1''
# Put it to playing
# Send a flush start event to it
# Send a flush stop event to it
# Put it to stop  ''p1''
# Put it to playing

The '''event_flush''' command will typically fail for any of the following:
* No pipeline was given
* The given pipeline doesn't exist
* Wrong flush event property 

Alternatively, a pipeline can be created using the [[Gstd-1.0 - Low-level Implementation for Applications|low level CRUD syntax]]:
<br>&rArr; ''Gstd Commands:''
<syntaxhighlight lang="bash" line="line" style="background-color:lavender">
create /pipelines/p1/event flush_start 
create /pipelines/p1/event flush_stop true 
</syntaxhighlight>




== API Summary ==

<html>
<table class="wikitable">
  <tr>
    <th>High Level Command</th>
    <th>Low Level CRUD</th> 
    <th>Description</th> 
  </tr>
  <tr>
    <td>event_flush_start &#60;pipeline&#62; </td>
    <td>create /pipelines/&#60;name&#62;/event flush_start </td> 
    <td>Put the pipeline in flushing mode </td> 
  </tr>
  <tr>
    <td>event_flush_stop  &#60;pipeline&#62; &#60;reset=true&#62; </td>
    <td>create /pipelines/&#60;name&#62;/event flush_stop &#60;reset=true&#62; </td> 
    <td>Take the pipeline out of flushing mode </td> 
  </tr>
</tr>
</tr>
</table>
</html>

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