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>9.2. Events</A
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> Events are control particles that are sent both up- and downstream in
a pipeline along with buffers. Downstream events notify fellow elements
of stream states. Possible events include seeking, flushes,
end-of-stream notifications and so on. Upstream events are used both
in application-element interaction as well as element-element interaction
to request changes in stream state, such as seeks. For applications,
only upstream events are important. Downstream events are just
explained to get a more complete picture of the data concept.
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> Since most applications seek in time units, our example below does so
too:
</P
><PRE
CLASS="programlisting"
> static void
seek_to_time (GstElement *element,
guint64 time_ns)
{
GstEvent *event;
event = gst_event_new_seek (1.0, GST_FORMAT_TIME,
GST_SEEK_FLAG_NONE,
GST_SEEK_METHOD_SET, time_ns,
GST_SEEK_TYPE_NONE, G_GUINT64_CONSTANT (0));
gst_element_send_event (element, event);
}
</PRE
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> The function <CODE
CLASS="function"
>gst_element_seek ()</CODE
> is a shortcut
for this. This is mostly just to show how it all works.
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