Struct gstreamer::Bin [−][src]
pub struct Bin(_);
Expand description
Bin is an element that can contain other Element, allowing them to be
managed as a group.
Pads from the child elements can be ghosted to the bin, see GhostPad.
This makes the bin look like any other elements and enables creation of
higher-level abstraction elements.
A new Bin is created with new(). Use a Pipeline instead if you
want to create a toplevel bin because a normal bin doesn’t have a bus or
handle clock distribution of its own.
After the bin has been created you will typically add elements to it with
GstBinExt::add(). You can remove elements with GstBinExt::remove().
An element can be retrieved from a bin with GstBinExt::by_name(), using the
elements name. GstBinExt::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.
An iterator of elements in a bin can be retrieved with
GstBinExtManual::iterate_elements(). Various other iterators exist to retrieve the
elements in a bin.
gst_object_unref() is used to drop your reference to the bin.
The signal::Bin::element-added signal is fired whenever a new element is added to
the bin. Likewise the signal::Bin::element-removed signal is fired whenever an
element is removed from the bin.
A Bin internally intercepts every Message posted by its children and
implements the following default behaviour for each of them:
-
GST_MESSAGE_EOS: This message is only posted by sinks in the PLAYING state. If all sinks posted the EOS message, this bin will post and EOS message upwards. -
GST_MESSAGE_SEGMENT_START: Just collected and never forwarded upwards. The messages are used to decide when all elements have completed playback of their segment. -
GST_MESSAGE_SEGMENT_DONE: Is posted byBinwhen all elements that posted a SEGMENT_START have posted a SEGMENT_DONE. -
GST_MESSAGE_DURATION_CHANGED: Is posted by an element that detected a change in the stream duration. The duration change is posted to the application so that it can refetch the new duration with a duration query.
Note that these messages can be posted before the bin is prerolled, in which case the duration query might fail.
Note also that there might be a discrepancy (due to internal buffering/queueing) between the stream being currently displayed and the returned duration query.
Applications might want to also query for duration (and changes) by
listening to the GST_MESSAGE_STREAM_START message, signaling the active start
of a (new) stream.
GST_MESSAGE_CLOCK_LOST: This message is posted by an element when it can no longer provide a clock.
The default bin behaviour is to check if the lost clock was the one provided by the bin. If so and the bin is currently in the PLAYING state, the message is forwarded to the bin parent.
This message is also generated when a clock provider is removed from the bin. If this message is received by the application, it should PAUSE the pipeline and set it back to PLAYING to force a new clock distribution.
GST_MESSAGE_CLOCK_PROVIDE: This message is generated when an element can provide a clock. This mostly happens when a new clock provider is added to the bin.
The default behaviour of the bin is to mark the currently selected clock as dirty, which will perform a clock recalculation the next time the bin is asked to provide a clock.
This message is never sent to the application but is forwarded to the parent of the bin.
- OTHERS: posted upwards.
A Bin implements the following default behaviour for answering to a
Query:
-
GST_QUERY_DURATION: The bin will forward the query to all sink elements contained within and will return the maximum value. If no sinks are available in the bin, the query fails. -
GST_QUERY_POSITION: The query is sent to all sink elements in the bin and the MAXIMUM of all values is returned. If no sinks are available in the bin, the query fails. -
OTHERS: the query is forwarded to all sink elements, the result of the first sink that answers the query successfully is returned. If no sink is in the bin, the query fails.
A Bin will by default forward any event sent to it to all sink
( EventTypeFlags::DOWNSTREAM ) or source ( EventTypeFlags::UPSTREAM ) elements
depending on the event type.
If all the elements return true, the bin will also return true, else false
is returned. If no elements of the required type are in the bin, the event
handler will return true.
Implements
GstBinExt, ElementExt, GstObjectExt, glib::ObjectExt, ChildProxyExt, ElementExtManual, ChildProxyExtManual
Implementations
Trait Implementations
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <=
operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
Returns the type identifier of Self.
Auto Trait Implementations
Blanket Implementations
Mutably borrows from an owned value. Read more
Upcasts an object to a superclass or interface T. Read more
Upcasts an object to a reference of its superclass or interface T. Read more
Tries to downcast to a subclass or interface implementor T. Read more
Tries to downcast to a reference of its subclass or interface implementor T. Read more
Tries to cast to an object of type T. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast and upcast will do many checks at compile-time already. Read more
Tries to cast to reference to an object of type T. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast and upcast will do many checks at compile-time already. Read more
Casts to T unconditionally. Read more
Casts to &T unconditionally. Read more
Returns true if the object is an instance of (can be cast to) T.
pub fn set_properties(
&self,
property_values: &[(&str, &dyn ToValue)]
) -> Result<(), BoolError>[src]pub fn set_properties_from_value(
&self,
property_values: &[(&str, Value)]
) -> Result<(), BoolError>[src]pub fn set_property<'a, N, V>(
&self,
property_name: N,
value: V
) -> Result<(), BoolError> where
V: ToValue,
N: Into<&'a str>, [src]pub fn set_property_from_value<'a, N>(
&self,
property_name: N,
value: &Value
) -> Result<(), BoolError> where
N: Into<&'a str>, [src]pub fn property<'a, N>(&self, property_name: N) -> Result<Value, BoolError> where
N: Into<&'a str>, [src]Safety Read more
Safety Read more
Safety Read more
Safety Read more
pub fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec) + Send + Sync, [src]pub fn connect_notify_local<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec), [src]pub unsafe fn connect_notify_unsafe<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: Fn(&T, &ParamSpec), [src]pub fn has_property<'a, N>(&self, property_name: N, type_: Option<Type>) -> bool where
N: Into<&'a str>, [src]pub fn find_property<'a, N>(&self, property_name: N) -> Option<ParamSpec> where
N: Into<&'a str>, [src]pub fn connect<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value> + Send + Sync + 'static,
N: Into<&'a str>, [src]Same as connect but takes a SignalId instead of a signal name.
pub fn connect_local<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value> + 'static,
N: Into<&'a str>, [src]Same as connect_local but takes a SignalId instead of a signal name.
pub unsafe fn connect_unsafe<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value>,
N: Into<&'a str>, [src]Same as connect_unsafe but takes a SignalId instead of a signal name.
Emit signal by signal id.
Emit signal with details by signal id.
Emit signal by it’s name.
pub fn bind_property<'a, O, N, M>(
&'a self,
source_property: N,
target: &'a O,
target_property: M
) -> BindingBuilder<'a> where
O: ObjectType,
N: Into<&'a str>,
M: Into<&'a str>, [src]Same as emit but takes Value for the arguments.
Same as emit_by_name but takes Value for the arguments.
Returns a SendValue clone of self.
impl<'a, T, C> FromValueOptional<'a> for T where
C: ValueTypeChecker<Error = ValueTypeMismatchOrNoneError>,
T: FromValue<'a, Checker = C>, [src]