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547 lines
8.9 KiB
Text
547 lines
8.9 KiB
Text
<!-- ##### SECTION Title ##### -->
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GstElement
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<!-- ##### SECTION Short_Description ##### -->
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Base class for all pipeline elements
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<!-- ##### SECTION Long_Description ##### -->
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<para>
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GstElement is the base class needed to construct an element that can be
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used in a GST pipeline. As such, it is not a functional entity, and
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cannot do anything when placed in a pipeline.
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</para>
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<para>
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All GstElements have a list containing the #GstPad structure for all their
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inputs and outputs. These can be added with gst_element_add_pad() or
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gst_element_add_ghost_pad(), and retrieved by name with
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gst_element_get_pad(), or in a list form by gst_element_get_pad_list().
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</para>
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<para>
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gst_element_connect() is a convenience function provided to make it
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simpler to connect pads of two elements together.
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</para>
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<!-- ##### SECTION See_Also ##### -->
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<para>
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#GstElementFactory
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</para>
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<!-- ##### ENUM GstElementState ##### -->
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<para>
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This enum defines the standard states an element may be in. You will normally
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use gst_element_set_state() to change the state of an element.
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</para>
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@GST_STATE_VOID_PENDING:
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@GST_STATE_NULL: Reset the state of an element.
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@GST_STATE_READY: will make the element ready to start processing data. some
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elements might have a non trivial way to initialize themselves.
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@GST_STATE_PAUSED: means there really is data flowing temporary stops the data flow.
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@GST_STATE_PLAYING: means there really is data flowing through the graph.
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<!-- ##### ENUM GstElementStateReturn ##### -->
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<para>
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This enum defines the standard return values that an element
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can return after a state change.
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</para>
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@GST_STATE_FAILURE: the element could not perform the state change
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@GST_STATE_SUCCESS: the element successfully changed its state
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@GST_STATE_ASYNC: the element will asynchronously change its state as soon as possible
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<!-- ##### MACRO GST_NUM_STATES ##### -->
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<para>
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The maximun number of states.
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</para>
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<!-- ##### MACRO GST_STATE ##### -->
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<para>
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This macro returns the current state of the element.
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</para>
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@obj: Element to return state for.
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<!-- ##### MACRO GST_STATE_PENDING ##### -->
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<para>
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This macro returns the currently pending state of the element.
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</para>
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@obj: Element to return the pending state for.
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<!-- ##### MACRO GST_STATE_TRANSITION ##### -->
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<para>
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Returns the state transition this object is going through.
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</para>
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@obj: the Element to return the state transition for
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<!-- ##### MACRO GST_STATE_NULL_TO_READY ##### -->
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<para>
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The Element is going from the NULL state to the READY state.
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</para>
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<!-- ##### MACRO GST_STATE_READY_TO_PAUSED ##### -->
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<para>
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The Element is going from the READY state to the PAUSED state.
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</para>
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<!-- ##### MACRO GST_STATE_PAUSED_TO_READY ##### -->
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<para>
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The Element is going from the PAUSED state to the READY state.
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</para>
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<!-- ##### MACRO GST_STATE_PLAYING_TO_PAUSED ##### -->
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<para>
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The Element is going from the PLAYING state to the PAUSED state.
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</para>
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<!-- ##### MACRO GST_STATE_PAUSED_TO_PLAYING ##### -->
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<para>
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The Element is going from the PAUSED state to the PLAYING state.
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</para>
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<!-- ##### MACRO GST_STATE_READY_TO_NULL ##### -->
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<para>
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The Element is going from the READY state to the NULL state.
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</para>
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<!-- ##### ENUM GstElementFlags ##### -->
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<para>
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This enum defines the standard flags that an element may have.
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</para>
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@GST_ELEMENT_COMPLEX:
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@GST_ELEMENT_DECOUPLED:
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@GST_ELEMENT_THREAD_SUGGESTED:
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@GST_ELEMENT_NO_SEEK:
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@GST_ELEMENT_NO_ENTRY:
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@GST_ELEMENT_NEW_LOOPFUNC:
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@GST_ELEMENT_COTHREAD_STOPPING:
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@GST_ELEMENT_USE_COTHREAD:
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@GST_ELEMENT_EVENT_AWARE:
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@GST_ELEMENT_FLAG_LAST:
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<!-- ##### MACRO GST_ELEMENT_IS_THREAD_SUGGESTED ##### -->
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<para>
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Queries whether the Element should be placed in a thread.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_IS_COTHREAD_STOPPING ##### -->
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<para>
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Queries whether the cothread holding this element needs to be stopped.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_IS_EOS ##### -->
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<para>
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Query wether this element is in the End Of Stream state.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_IS_EVENT_AWARE ##### -->
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<para>
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Query wether this element can handle events.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_PARENT ##### -->
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<para>
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Get the parent object of this element.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_NAME ##### -->
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<para>
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Get the name of this element.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_PADS ##### -->
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<para>
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Get the pads of this elements.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_SCHED ##### -->
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<para>
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Get the scheduler of this element.
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</para>
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@obj: The element to query
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<!-- ##### MACRO GST_ELEMENT_MANAGER ##### -->
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<para>
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Get the manager of this element.
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</para>
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@obj: The element to query
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<!-- ##### STRUCT GstElement ##### -->
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<para>
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</para>
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<!-- ##### USER_FUNCTION GstElementLoopFunction ##### -->
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<para>
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This function type is used to specify a loop function for the element. It
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is passed the element in question, and is expect to return only in error
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circumstances.
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</para>
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@element: The element in question.
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<!-- ##### FUNCTION gst_element_class_add_padtemplate ##### -->
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<para>
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</para>
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@klass:
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@templ:
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<!-- # Unused Parameters # -->
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@element:
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<!-- ##### MACRO gst_element_destroy ##### -->
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<para>
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Destroy the element. This is potentially dangerous, use gst_object_unref
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instead.
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</para>
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@element: the element to destroy
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<!-- ##### FUNCTION gst_element_set_loop_function ##### -->
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<para>
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</para>
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@element:
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@loop:
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<!-- ##### FUNCTION gst_element_set_name ##### -->
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<para>
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</para>
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@element:
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@name:
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<!-- ##### FUNCTION gst_element_get_name ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- ##### FUNCTION gst_element_get_sched ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- ##### FUNCTION gst_element_set_sched ##### -->
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<para>
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</para>
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@element:
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@sched:
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<!-- ##### FUNCTION gst_element_set_parent ##### -->
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<para>
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</para>
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@element:
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@parent:
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<!-- ##### FUNCTION gst_element_get_parent ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- ##### FUNCTION gst_element_add_pad ##### -->
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<para>
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</para>
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@element:
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@pad:
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<!-- ##### FUNCTION gst_element_remove_pad ##### -->
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<para>
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</para>
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@element:
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@pad:
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<!-- ##### FUNCTION gst_element_get_pad ##### -->
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<para>
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</para>
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@element:
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@name:
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@Returns: GList of pads
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<!-- ##### FUNCTION gst_element_get_pad_list ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- ##### FUNCTION gst_element_get_padtemplate_list ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- ##### FUNCTION gst_element_get_padtemplate_by_name ##### -->
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<para>
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</para>
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@element:
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@name:
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@Returns:
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<!-- ##### FUNCTION gst_element_add_ghost_pad ##### -->
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<para>
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</para>
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@element:
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@pad:
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@name:
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<!-- ##### FUNCTION gst_element_remove_ghost_pad ##### -->
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<para>
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</para>
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@element:
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@pad:
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<!-- ##### FUNCTION gst_element_request_compatible_pad ##### -->
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<para>
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</para>
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@element:
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@templ:
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@Returns:
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<!-- ##### FUNCTION gst_element_request_pad_by_name ##### -->
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<para>
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</para>
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@element:
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@name:
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@Returns:
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<!-- ##### FUNCTION gst_element_connect ##### -->
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<para>
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</para>
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@src:
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@srcpadname:
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@dest:
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@destpadname:
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<!-- ##### FUNCTION gst_element_disconnect ##### -->
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<para>
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</para>
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@src:
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@srcpadname:
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@dest:
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@destpadname:
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<!-- ##### FUNCTION gst_element_set_state ##### -->
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<para>
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</para>
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@element:
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@state:
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@Returns:
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<!-- ##### FUNCTION gst_element_get_state ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- # Unused Parameters # -->
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@elem:
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<!-- ##### FUNCTION gst_element_wait_state_change ##### -->
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<para>
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</para>
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@element:
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<!-- ##### FUNCTION gst_element_statename ##### -->
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<para>
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</para>
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@state:
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@Returns:
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<!-- ##### FUNCTION gst_element_error ##### -->
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<para>
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</para>
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@element:
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@error:
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<!-- ##### FUNCTION gst_element_get_factory ##### -->
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<para>
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</para>
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@element:
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@Returns:
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<!-- ##### FUNCTION gst_element_signal_eos ##### -->
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<para>
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</para>
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@element:
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<!-- ##### FUNCTION gst_element_restore_thyself ##### -->
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<para>
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</para>
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@self:
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@parent:
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@Returns:
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<!-- ##### SIGNAL GstElement::state-change ##### -->
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<para>
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Is trigered whenever the state of an element changes
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</para>
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@gstelement: the object which received the signal.
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@arg1: the new state of the object
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@arg2:
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<!-- ##### SIGNAL GstElement::new-pad ##### -->
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<para>
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Is trigered whenever a new pad is added to an element
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</para>
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@gstelement: the object which received the signal.
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@arg1: the new pad that was added
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<!-- ##### SIGNAL GstElement::pad-removed ##### -->
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<para>
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</para>
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@gstelement: the object which received the signal.
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@arg1: The pad that was removed.
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<!-- ##### SIGNAL GstElement::error ##### -->
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<para>
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Is trigered whenever an error occured
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</para>
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@gstelement: the object which received the signal.
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@arg1: the error message
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<!-- ##### SIGNAL GstElement::eos ##### -->
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<para>
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</para>
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@gstelement: the object which received the signal.
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