gstreamer/docs/gst/tmpl/gstpad.sgml
Wim Taymans 51cbf22624 This is a megapatch with the following changes:
Original commit message from CVS:
This is a megapatch with the following changes:

- moved the gchar *name to GstObject, removed the ones in GstElement and
GstPad.
- moved the parent handling completely into GstObject. This cause *all* of
the plugins to fail (except those that used gst_pad_get_parent)
- rearanged the XML save handling.
- GstObject now has a class function save/restore_thyself.
- GstObject has a generic method gst_object_save_thyself, this makes it
possible to fire a signal wehever a new object is loaded. This is needed
so we can add XML save hooks.
- GstXML API has changed slightly. You now have to create a GstXML object
first before you can actually load something. This makes it possible to
attach a signal to GstXML whenever an object is loaded. I'm not sure we
will keep this interface.
- GstObject can now print the path_string without knowing about the GstPad and
GstElement types.
- Added gst_bin_get_by_name_recurse_up to lookup an element in the current
element hierarchy.
- added XML namespaces to the saved pipelines the namespace is:
http://gstreamer.net/gst-core/1.0/
namespaces are needed to distinguish user generated XML from the core XML.

Note that the plugins still contain a macro GST_OBJECT_PARENT that will be
replaced with gst_pad_get_parent shortly.
2001-01-29 00:06:02 +00:00

780 lines
11 KiB
Text

<!-- ##### SECTION Title ##### -->
GstPad
<!-- ##### SECTION Short_Description ##### -->
The connection between Elements
<!-- ##### SECTION Long_Description ##### -->
<para>
Elements are connected to each other via "pads", which are extremely light-weight generic
connections.
</para>
<!-- ##### SECTION See_Also ##### -->
<para>
</para>
<!-- ##### MACRO GST_PAD_NAME ##### -->
<para>
Get the name of the pad.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_ELEMENT_PRIVATE ##### -->
<para>
Get the private data set by the element that owns the pad.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_PARENT ##### -->
<para>
Get the parent element of this pad.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_PADTEMPLATE ##### -->
<para>
Get the padtemplate that was used to create this pad. NULL if no padtemplate
was used.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_REALIZE ##### -->
<para>
Return the real pad of this pad.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_DIRECTION ##### -->
<para>
Get the pad direction.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_CAPS ##### -->
<para>
Get the capabilities of a pad.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_PEER ##### -->
<para>
Get the peerpad of this pad.
</para>
@pad: the pad to query
<!-- ##### MACRO GST_PAD_CONNECTED ##### -->
<para>
Is this pad connected.
</para>
@pad: the pad to check
<!-- ##### MACRO GST_PAD_CAN_PULL ##### -->
<para>
Can this pad be used to pull a buffer.
</para>
@pad: the pad to check
<!-- ##### STRUCT GstPad ##### -->
<para>
</para>
<!-- ##### USER_FUNCTION GstPadChainFunction ##### -->
<para>
The function that will be called when chaining buffers.
</para>
@pad: the pad that performed the chain
@buf: the buffer that is chained
<!-- ##### USER_FUNCTION GstPadGetFunction ##### -->
<para>
The function that will be called when pulling a buffer.
</para>
@pad: the pad to get a buffer from
@Returns: a #GstBuffer
<!-- ##### USER_FUNCTION GstPadGetRegionFunction ##### -->
<para>
The function that will be called when pulling a region buffer.
</para>
@pad: the pad to get a buffer from
@offset: the offset of the region to get
@size: the size of the region to get
@Returns: a #GstBuffer
<!-- ##### USER_FUNCTION GstPadQoSFunction ##### -->
<para>
The function that will be called when a QoS message is sent.
</para>
@pad: the pad that sent the QoS message
@qos_message: the message
<!-- ##### USER_FUNCTION GstPadEOSFunction ##### -->
<para>
The function that will be called in an EOS case.
</para>
@pad: the pad that needs to be set to EOS state
@Returns: TRUE if EOS was successful, FALSE otherwise
<!-- ##### USER_FUNCTION GstPadPushFunction ##### -->
<para>
The function that will be called when pushing a buffers.
</para>
@pad: the pad to push
@buf: a GstBuffer to push
<!-- ##### USER_FUNCTION GstPadPullFunction ##### -->
<para>
The function that will be called when pulling buffers.
</para>
@pad: the pad to pull
@Returns: a GstBuffer
<!-- ##### USER_FUNCTION GstPadPullRegionFunction ##### -->
<para>
The function that will be called when pulling a region buffer.
</para>
@pad: the pad to pull
@offset: the offset of the region to pull
@size: the size of the region to pull
@Returns: a GstBuffer
<!-- ##### ENUM GstPadDirection ##### -->
<para>
The direction this pad is.
</para>
@GST_PAD_UNKNOWN: direction is unknown
@GST_PAD_SRC: this is a source pad
@GST_PAD_SINK: this is a sink pad
<!-- ##### ENUM GstPadFlags ##### -->
<para>
Flags for the pad.
</para>
@GST_PAD_DISABLED: the pad is disabled
@GST_PAD_EOS: the pad is in end of stream state
@GST_PAD_FLAG_LAST: subclasses can use this number to enumerate their flags
<!-- ##### FUNCTION gst_pad_new ##### -->
<para>
</para>
@name:
@direction:
@Returns:
<!-- ##### MACRO gst_pad_destroy ##### -->
<para>
Destroy the pad.
</para>
@pad: the pad to destroy
<!-- ##### FUNCTION gst_pad_new_from_template ##### -->
<para>
</para>
@templ:
@name:
@Returns:
<!-- # Unused Parameters # -->
@temp:
<!-- ##### FUNCTION gst_pad_get_direction ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_set_chain_function ##### -->
<para>
</para>
@pad:
@chain:
<!-- ##### FUNCTION gst_pad_set_get_function ##### -->
<para>
</para>
@pad:
@get:
<!-- ##### FUNCTION gst_pad_set_getregion_function ##### -->
<para>
</para>
@pad:
@getregion:
<!-- ##### FUNCTION gst_pad_set_qos_function ##### -->
<para>
</para>
@pad:
@qos:
<!-- ##### FUNCTION gst_pad_set_eos_function ##### -->
<para>
</para>
@pad:
@eos:
<!-- ##### FUNCTION gst_pad_set_caps_list ##### -->
<para>
</para>
@pad:
@caps:
<!-- ##### FUNCTION gst_pad_get_caps_list ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_get_caps_by_name ##### -->
<para>
</para>
@pad:
@name:
@Returns:
<!-- ##### FUNCTION gst_pad_check_compatibility ##### -->
<para>
</para>
@srcpad:
@sinkpad:
@Returns:
<!-- ##### FUNCTION gst_pad_set_name ##### -->
<para>
</para>
@pad:
@name:
<!-- ##### FUNCTION gst_pad_get_name ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_set_element_private ##### -->
<para>
</para>
@pad:
@priv:
<!-- ##### FUNCTION gst_pad_get_element_private ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_set_parent ##### -->
<para>
</para>
@pad:
@parent:
<!-- ##### FUNCTION gst_pad_get_parent ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_add_ghost_pad ##### -->
<para>
</para>
@pad:
@ghostpad:
<!-- ##### FUNCTION gst_pad_remove_ghost_pad ##### -->
<para>
</para>
@pad:
@ghostpad:
<!-- ##### FUNCTION gst_pad_get_ghost_pad_list ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_get_peer ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_connect ##### -->
<para>
</para>
@srcpad:
@sinkpad:
<!-- ##### FUNCTION gst_pad_disconnect ##### -->
<para>
</para>
@srcpad:
@sinkpad:
<!-- ##### FUNCTION gst_pad_push ##### -->
<para>
</para>
@pad:
@buffer:
<!-- ##### FUNCTION gst_pad_pull ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_pull_region ##### -->
<para>
</para>
@pad:
@offset:
@size:
@Returns:
<!-- ##### MACRO gst_pad_pullregion ##### -->
<para>
</para>
@pad:
@offset:
@size:
<!-- ##### FUNCTION gst_pad_select ##### -->
<para>
</para>
@nextpad:
@Varargs:
@Returns:
<!-- ##### FUNCTION gst_pad_set_eos ##### -->
<para>
</para>
@pad:
@Returns:
<!-- ##### FUNCTION gst_pad_handle_qos ##### -->
<para>
</para>
@pad:
@qos_message:
<!-- ##### MACRO gst_pad_eos ##### -->
<para>
Call the EOS function of the pad
</para>
@pad: the pad to call the eos function of.
<!-- ##### FUNCTION gst_pad_load_and_connect ##### -->
<para>
</para>
@self:
@parent:
<!-- # Unused Parameters # -->
@element:
@elements:
<!-- ##### STRUCT GstRealPad ##### -->
<para>
</para>
@pad:
@caps:
@direction:
@threadstate:
@peer:
@bufpen:
@chainfunc:
@getfunc:
@getregionfunc:
@qosfunc:
@eosfunc:
@pushfunc:
@pullfunc:
@pullregionfunc:
@ghostpads:
<!-- ##### MACRO GST_RPAD_DIRECTION ##### -->
<para>
Get the direction of the real pad.
</para>
@pad: the realpad to query.
<!-- ##### MACRO GST_RPAD_CAPS ##### -->
<para>
Get the caps of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_PEER ##### -->
<para>
Get the peer element of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_BUFPEN ##### -->
<para>
Get the bufpen of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_CHAINFUNC ##### -->
<para>
Get the chain function of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_GETFUNC ##### -->
<para>
Get get getfunction of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_GETREGIONFUNC ##### -->
<para>
Get the getregion function of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_PUSHFUNC ##### -->
<para>
Get the pushfunction of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_PULLFUNC ##### -->
<para>
Get the pullfunction of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_PULLREGIONFUNC ##### -->
<para>
Get the pullregion function of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_QOSFUNC ##### -->
<para>
Get the QoS function of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_RPAD_EOSFUNC ##### -->
<para>
Get the EOS function of the real pad.
</para>
@pad: the real pad to query.
<!-- ##### MACRO GST_GPAD_REALPAD ##### -->
<para>
Get the real pad of this ghost pad.
</para>
@pad: the real pad to query.
<!-- ##### STRUCT GstGhostPad ##### -->
<para>
</para>
@pad:
@realpad:
<!-- ##### FUNCTION gst_ghost_pad_new ##### -->
<para>
</para>
@name:
@pad:
@Returns:
<!-- ##### TYPEDEF GstPadFactoryEntry ##### -->
<para>
Defines an entry for a padfactory.
</para>
<!-- ##### TYPEDEF GstPadFactory[] ##### -->
<para>
The padfactory.
</para>
<!-- ##### MACRO GST_PAD_FACTORY_SOMETIMES ##### -->
<para>
Indicate that this pad will become available depending
on the media type. Use this in the factory definition.
</para>
<!-- ##### MACRO GST_PAD_FACTORY_ALWAYS ##### -->
<para>
Indicate that this pad will always be available.
Use this in the factory definition.
</para>
<!-- ##### MACRO GST_PAD_FACTORY_REQUEST ##### -->
<para>
Indicates that this pad will be available on request. Use
this in the factory definition.
</para>
<!-- ##### MACRO GST_PAD_FACTORY_SINK ##### -->
<para>
Indicates a sinkpad for the padfactory.
</para>
<!-- ##### MACRO GST_PAD_FACTORY_SRC ##### -->
<para>
Indicates a srcpad for the padfactory.
</para>
<!-- ##### MACRO GST_PAD_FACTORY_CAPS ##### -->
<para>
Starts the declaration of a the capabilities for this padtemplate.
</para>
@a...: a capability factory
<!-- ##### ENUM GstPadPresence ##### -->
<para>
Indicates when this pad will become available.
</para>
@GST_PAD_ALWAYS: the pad is always available
@GST_PAD_SOMETIMES: the pad will become available depending on the media stream
@GST_PAD_REQUEST:
<!-- ##### STRUCT GstPadTemplate ##### -->
<para>
</para>
@object:
@name_template:
@direction:
@presence:
@caps:
<!-- ##### FUNCTION gst_padtemplate_new ##### -->
<para>
</para>
@factory:
@Returns:
<!-- ##### FUNCTION gst_padtemplate_create ##### -->
<para>
</para>
@name_template:
@direction:
@presence:
@caps:
@Returns:
<!-- ##### FUNCTION gst_padtemplate_load_thyself ##### -->
<para>
</para>
@parent:
@Returns:
<!-- ##### FUNCTION gst_padtemplate_save_thyself ##### -->
<para>
</para>
@templ:
@parent:
@Returns:
<!-- # Unused Parameters # -->
@pad: