gstreamer/docs/gst/tmpl/gstbin.sgml

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<!-- ##### SECTION Title ##### -->
GstBin
<!-- ##### SECTION Short_Description ##### -->
Base container element
<!-- ##### SECTION Long_Description ##### -->
<para>
GstBin is the simplest of the container elements, allowing elements to
become children of itself. Pads from the child elements can be ghosted to
the bin, making the bin itself look transparently like any other element,
allowing for deep nesting of predefined sub-pipelines.
</para>
<para>
A new GstBin is created with gst_bin_new(). Use a #GstPipeline instead if you want
to create a toplevel bin because a normal bin doesn't have a scheduler of its
own.
</para>
<para>
After the bin has been created you will typically add elements to it with
gst_bin_add(). You can remove elements with gst_bin_remove().
</para>
<para>
An element can be retrieved from a bin with gst_bin_get_by_name(), using the
elements name. gst_bin_get_by_name_recurse_up() is mainly used for internal
purposes and will query the parent bins when the element is not found in the
current bin.
</para>
<para>
The list of elements in a bin can be retrieved with gst_bin_get_list().
</para>
<para>
After the bin has been set to the PLAYING state (with gst_element_set_state()),
gst_bin_iterate() is used to process the elements in the bin.
</para>
<para>
The "object_added" signal is fired whenever a new object is added to the bin.
</para>
<para>
gst_bin_destroy() is used to destroy the bin.
</para>
<para>
To control the selection of the clock in a bin, you can use the following methods:
gst_bin_auto_clock() to let the bin select a clock automatically, gst_bin_get_clock() to
get the current clock of the bin and gst_bin_use_clock() to specify a clock explicitly.
</para>
<!-- ##### SECTION See_Also ##### -->
<para>
</para>
<!-- ##### ENUM GstBinFlags ##### -->
<para>
Flags for a bin.
</para>
@GST_BIN_FLAG_MANAGER: This bin has a scheduler and can be used as a toplevel bin.
@GST_BIN_SELF_SCHEDULABLE: This bin iterates itself, so no calls to gst_bin_iterate() should be made.
@GST_BIN_FLAG_PREFER_COTHREADS: This bin preferes to have its elements scheduled with cothreads
@GST_BIN_FLAG_FIXED_CLOCK: This bin uses a fixed clock, possibly the one set with gst_bin_use_clock().
@GST_BIN_FLAG_LAST:
<!-- ##### STRUCT GstBin ##### -->
<para>
The GstBin object
</para>
<!-- ##### USER_FUNCTION GstBinPrePostIterateFunction ##### -->
<para>
The signature of the callback for the post and pre iterate function as set with
gst_bin_set_pre_iterate_function() and gst_bin_set_post_iterate_function().
</para>
@bin: The bin that performed the callback
@data: user data
<!-- ##### FUNCTION gst_bin_new ##### -->
<para>
</para>
@name:
@Returns:
<!-- ##### MACRO gst_bin_destroy ##### -->
<para>
Free the memory allocated by this bin
</para>
@bin: the bin to free
<!-- ##### FUNCTION gst_bin_add ##### -->
<para>
</para>
@bin:
@element:
<!-- ##### FUNCTION gst_bin_add_many ##### -->
<para>
</para>
@bin:
@element_1:
@Varargs:
<!-- ##### FUNCTION gst_bin_remove ##### -->
<para>
</para>
@bin:
@element:
<!-- ##### FUNCTION gst_bin_get_by_name ##### -->
<para>
</para>
@bin:
@name:
@Returns:
<!-- ##### FUNCTION gst_bin_get_by_name_recurse_up ##### -->
<para>
</para>
@bin:
@name:
@Returns:
<!-- ##### FUNCTION gst_bin_get_list ##### -->
<para>
</para>
@bin:
@Returns:
<!-- ##### FUNCTION gst_bin_iterate ##### -->
<para>
</para>
@bin:
@Returns:
<!-- ##### FUNCTION gst_bin_set_post_iterate_function ##### -->
<para>
</para>
@bin:
@func:
@func_data:
<!-- ##### FUNCTION gst_bin_set_pre_iterate_function ##### -->
<para>
</para>
@bin:
@func:
@func_data:
<!-- ##### FUNCTION gst_bin_child_state_change ##### -->
<para>
</para>
@bin:
@oldstate:
@newstate:
@child:
<!-- ##### FUNCTION gst_bin_auto_clock ##### -->
<para>
</para>
@bin:
<!-- ##### FUNCTION gst_bin_get_clock ##### -->
<para>
</para>
@bin:
@Returns:
<!-- ##### FUNCTION gst_bin_use_clock ##### -->
<para>
</para>
@bin:
@clock:
<!-- ##### SIGNAL GstBin::object-added ##### -->
<para>
is signaled whenever a new <classname>GstElement</classname> is added to the <classname>GstBin</classname>
</para>
@gstbin: the object which received the signal.
@arg1: the element that was added