gstreamer/docs/gst/tmpl/gstelement.sgml

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<!-- ##### SECTION Title ##### -->
GstElement
<!-- ##### SECTION Short_Description ##### -->
Base class for all pipeline elements
<!-- ##### SECTION Long_Description ##### -->
<para>
GstElement is the base class needed to construct an element that can be
used in a GST pipeline. As such, it is not a functional entity, and
cannot do anything when placed in a pipeline.
</para>
<para>
All GstElements have a list containing the #GstPad structure for all their
inputs and outputs. These can be added with gst_element_add_pad() or
gst_element_add_ghost_pad(), and retrieved by name with
gst_element_get_pad(), or in a list form by gst_element_get_pad_list().
</para>
<para>
gst_element_connect() is a convenience function provided to make it
simpler to connect pads of two elements together.
</para>
<!-- ##### SECTION See_Also ##### -->
<para>
</para>
<!-- ##### ENUM GstElementState ##### -->
<para>
This enum defines the standard states an element may be in. You will normally
use gst_element_set_state() to change the state of an element.
</para>
@GST_STATE_NONE_PENDING: The element is in the desired state.
@GST_STATE_NULL: Reset the state of an element.
@GST_STATE_READY: will make the element ready to start processing data. some
elements might have a non trivial way to initialize themselves.
@GST_STATE_PLAYING: means there really is data flowing through the graph.
@GST_STATE_PAUSED: means there really is data flowing temporary stops the data flow.
<!-- ##### ENUM GstElementStateReturn ##### -->
<para>
This enum defines the standard return values that an element
can return after a state change.
</para>
@GST_STATE_FAILURE: the element could not perform the state change
@GST_STATE_SUCCESS: the element successfully changed its state
@GST_STATE_ASYNC: the element will asynchronously change its state as soon as possible
<!-- ##### MACRO GST_STATE ##### -->
<para>
This macro returns the current state of the element.
</para>
@obj: Element to return state for.
<!-- ##### MACRO GST_STATE_PENDING ##### -->
<para>
This macro returns the currently pending state of the element.
</para>
@obj: Element to return the pending state for.
<!-- ##### MACRO GST_STATE_TRANSITION ##### -->
<para>
Returns the state transition this object is going through.
</para>
@obj: the Element to return the state transition for
<!-- ##### MACRO GST_STATE_NULL_TO_READY ##### -->
<para>
The Element is going from the NULL state to the READY state.
</para>
<!-- ##### MACRO GST_STATE_READY_TO_PLAYING ##### -->
<para>
The Element is going from the READY state to the PLAYING state.
</para>
<!-- ##### MACRO GST_STATE_PLAYING_TO_PAUSED ##### -->
<para>
The Element is going from the PLAYING state to the PAUSED state.
</para>
<!-- ##### MACRO GST_STATE_PAUSED_TO_PLAYING ##### -->
<para>
The Element is going from the PAUSED state to the PLAYING state.
</para>
<!-- ##### MACRO GST_STATE_PLAYING_TO_READY ##### -->
<para>
The Element is going from the PLAYING state to the READY state.
</para>
<!-- ##### MACRO GST_STATE_READY_TO_NULL ##### -->
<para>
The Element is going from the READY state to the NULL state.
</para>
<!-- ##### ENUM GstElementFlags ##### -->
<para>
This enum defines the standard flags that an element may have.
</para>
@GST_ELEMENT_COMPLEX:
@GST_ELEMENT_DECOUPLED:
@GST_ELEMENT_THREAD_SUGGESTED:
@GST_ELEMENT_NO_SEEK:
@GST_ELEMENT_NEW_LOOPFUNC:
@GST_ELEMENT_COTHREAD_STOPPING:
@GST_ELEMENT_USE_COTHREAD:
@GST_ELEMENT_EOS:
@GST_ELEMENT_FLAG_LAST:
<!-- ##### MACRO GST_ELEMENT_IS_THREAD_SUGGESTED ##### -->
<para>
Queries whether the Element should be placed in a thread.
</para>
@obj: The element to query
<!-- ##### MACRO GST_ELEMENT_IS_COTHREAD_STOPPING ##### -->
<para>
Queries whether the cothread holding this element needs to be stopped.
</para>
@obj: The element to query
<!-- ##### MACRO GST_ELEMENT_IS_EOS ##### -->
<para>
Query wether this element is in the End Of Stream state.
</para>
@obj: The element to query
<!-- ##### MACRO GST_ELEMENT_PARENT ##### -->
<para>
Get the parent object of this element.
</para>
@obj: The element to query
<!-- ##### MACRO GST_ELEMENT_NAME ##### -->
<para>
Get the name of this element.
</para>
@obj: The element to query
<!-- ##### MACRO GST_ELEMENT_PADS ##### -->
<para>
Get the pads of this elements.
</para>
@obj: The element to query
<!-- ##### STRUCT GstElement ##### -->
<para>
</para>
<!-- ##### STRUCT GstElementDetails ##### -->
<para>
This struct is used to define public information about the element. It
describes the element, mostly for the benefit of editors.
</para>
@longname:
@klass:
@description:
@version:
@author:
@copyright:
<!-- ##### STRUCT GstElementFactory ##### -->
<para>
This factory is used when registering the element, and contains the name
of the element, the GtkType value for it, as well as a pointer to the
GstElementDetails struct for the element.
</para>
@name:
@type:
@details:
@padtemplates:
@numpadtemplates:
<!-- ##### USER_FUNCTION GstElementLoopFunction ##### -->
<para>
This function type is used to specify a loop function for the element. It
is passed the element in question, and is expect to return only in error
circumstances.
</para>
@element: The element in question.
<!-- ##### FUNCTION gst_element_new ##### -->
<para>
</para>
@Returns:
<!-- ##### MACRO gst_element_destroy ##### -->
<para>
</para>
@element: the element to destroy
<!-- ##### FUNCTION gst_element_set_loop_function ##### -->
<para>
</para>
@element:
@loop:
<!-- ##### FUNCTION gst_element_set_name ##### -->
<para>
</para>
@element:
@name:
<!-- ##### FUNCTION gst_element_get_name ##### -->
<para>
</para>
@element:
@Returns:
<!-- ##### FUNCTION gst_element_set_manager ##### -->
<para>
</para>
@element:
@manager:
<!-- ##### FUNCTION gst_element_get_manager ##### -->
<para>
</para>
@element:
@Returns:
<!-- ##### FUNCTION gst_element_set_parent ##### -->
<para>
</para>
@element:
@parent:
<!-- ##### FUNCTION gst_element_get_parent ##### -->
<para>
</para>
@element:
@Returns:
<!-- ##### FUNCTION gst_element_add_pad ##### -->
<para>
</para>
@element:
@pad:
<!-- ##### FUNCTION gst_element_get_pad ##### -->
<para>
</para>
@element:
@name:
@Returns: GList of pads
<!-- ##### FUNCTION gst_element_get_pad_list ##### -->
<para>
</para>
@element:
@Returns:
<!-- ##### FUNCTION gst_element_get_padtemplate_list ##### -->
<para>
</para>
@element:
@Returns:
<!-- ##### FUNCTION gst_element_get_padtemplate_by_name ##### -->
<para>
</para>
@element:
@name:
@Returns:
<!-- ##### FUNCTION gst_element_add_ghost_pad ##### -->
<para>
</para>
@element:
@pad:
@name:
<!-- ##### FUNCTION gst_element_remove_ghost_pad ##### -->
<para>
</para>
@element:
@pad:
<!-- ##### FUNCTION gst_element_request_compatible_pad ##### -->
<para>
</para>
@element:
@templ:
@Returns:
<!-- ##### FUNCTION gst_element_request_pad_by_name ##### -->
<para>
</para>
@element:
@name:
@Returns:
<!-- ##### FUNCTION gst_element_connect ##### -->
<para>
</para>
@src:
@srcpadname:
@dest:
@destpadname:
<!-- ##### FUNCTION gst_element_disconnect ##### -->
<para>
</para>
@src:
@srcpadname:
@dest:
@destpadname:
<!-- ##### FUNCTION gst_element_set_state ##### -->
<para>
</para>
@element:
@state:
@Returns:
<!-- ##### FUNCTION gst_element_error ##### -->
<para>
</para>
@element:
@error:
<!-- ##### FUNCTION gst_element_get_factory ##### -->
<para>
</para>
@element:
@Returns:
<!-- ##### FUNCTION gst_element_signal_eos ##### -->
<para>
</para>
@element:
<!-- ##### FUNCTION gst_element_load_thyself ##### -->
<para>
</para>
@self:
@parent:
@Returns:
<!-- # Unused Parameters # -->
@elements:
<!-- ##### FUNCTION gst_elementfactory_new ##### -->
<para>
</para>
@name:
@type:
@details:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_destroy ##### -->
<para>
</para>
@elementfactory:
<!-- ##### FUNCTION gst_elementfactory_add_padtemplate ##### -->
<para>
</para>
@elementfactory:
@templ:
<!-- # Unused Parameters # -->
@temp:
@pad:
<!-- ##### FUNCTION gst_elementfactory_find ##### -->
<para>
</para>
@name:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_get_list ##### -->
<para>
</para>
@Returns:
<!-- ##### FUNCTION gst_elementfactory_can_src_caps ##### -->
<para>
</para>
@factory:
@caps:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_can_sink_caps ##### -->
<para>
</para>
@factory:
@caps:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_create ##### -->
<para>
</para>
@factory:
@name:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_make ##### -->
<para>
</para>
@factoryname:
@name:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_save_thyself ##### -->
<para>
</para>
@factory:
@parent:
@Returns:
<!-- ##### FUNCTION gst_elementfactory_load_thyself ##### -->
<para>
</para>
@parent:
@Returns:
<!-- ##### SIGNAL GstElement::state-change ##### -->
<para>
Is trigered whenever the state of an element changes
</para>
@gstelement: the object which received the signal.
@arg1: the new state of the object
<!-- ##### SIGNAL GstElement::new-pad ##### -->
<para>
Is trigered whenever a new pad is added to an element
</para>
@gstelement: the object which received the signal.
@arg1: the new pad that was added
<!-- ##### SIGNAL GstElement::new-ghost-pad ##### -->
<para>
Is trigered whenever a new ghost pad is added to an element
</para>
@gstelement: the object which received the signal.
@arg1: the new ghost pad that was added
<!-- ##### SIGNAL GstElement::error ##### -->
<para>
Is trigered whenever an error occured
</para>
@gstelement: the object which received the signal.
@arg1: the error message
<!-- ##### SIGNAL GstElement::eos ##### -->
<para>
</para>
@gstelement: the object which received the signal.