Struct gstreamer::Object [−][src]
pub struct Object(_);
Expand description
Object provides a root for the object hierarchy tree filed in by the
GStreamer library. It is currently a thin wrapper on top of
GInitiallyUnowned. It is an abstract class that is not very usable on its own.
Object gives us basic refcounting, parenting functionality and locking.
Most of the functions are just extended for special GStreamer needs and can be
found under the same name in the base class of Object which is glib::Object
(e.g. g_object_ref() becomes gst_object_ref()).
Since Object derives from GInitiallyUnowned, it also inherits the
floating reference. Be aware that functions such as GstBinExt::add() and
ElementExt::add_pad() take ownership of the floating reference.
In contrast to glib::Object instances, Object adds a name property. The functions
gst_object_set_name() and GstObjectExt::name() are used to set/get the name
of the object.
controlled properties
Controlled properties offers a lightweight way to adjust gobject properties over stream-time. It works by using time-stamped value pairs that are queued for element-properties. At run-time the elements continuously pull value changes for the current stream-time.
What needs to be changed in a Element?
Very little - it is just two steps to make a plugin controllable!
-
mark gobject-properties paramspecs that make sense to be controlled, by GST_PARAM_CONTROLLABLE.
-
when processing data (get, chain, loop function) at the beginning call gst_object_sync_values(element,timestamp). This will make the controller update all GObject properties that are under its control with the current values based on the timestamp.
What needs to be done in applications? Again it’s not a lot to change.
-
create a
ControlSource. csource = gst_interpolation_control_source_new (); g_object_set (csource, “mode”, GST_INTERPOLATION_MODE_LINEAR, NULL); -
Attach the
ControlSourceon the controller to a property. gst_object_add_control_binding (object, gst_direct_control_binding_new (object, “prop1”, csource)); -
Set the control values gst_timed_value_control_source_set ((GstTimedValueControlSource *)csource,0 * GST_SECOND, value1); gst_timed_value_control_source_set ((GstTimedValueControlSource *)csource,1 * GST_SECOND, value2);
-
start your pipeline
This is an Abstract Base Class, you cannot instantiate it.
Implements
Implementations
Checks to see if there is any object named name in list. This function
does not do any locking of any kind. You might want to protect the
provided list with the lock of the owner of the list. This function
will lock each Object in the list to compare the name, so be
careful when passing a list with a locked object.
list
a list of Object to
check through
name
the name to search for
Returns
true if a Object named name does not appear in list,
false if it does.
MT safe. Grabs and releases the LOCK of each object in the list.
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.
v1_10 only.v1_10 only.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]