Struct gstreamer::Object

pub struct Object { /* private fields */ }

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 ControlSource on 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.

Properties

name

Readable | Writeable | Construct

parent

The parent of the object. Please note, that when changing the ‘parent’ property, we don’t emit notify and deep-notify signals due to locking issues. In some cases one can use element-added or element-removed signals on the parent to achieve a similar effect.

Readable | Writeable

Signals

deep-notify

The deep notify signal is used to be notified of property changes. It is typically attached to the toplevel bin to receive notifications from all the elements contained in that bin.

Detailed

Implements

GstObjectExt, [trait@glib::ObjectExt]

GLib type: GObject with reference counted clone semantics.

Implementations

impl Object

pub const NONE: Option<&'static Object> = None

pub fn check_uniqueness(list: &[Object], name: &str) -> bool

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

impl Clone for Object

fn clone(&self) -> Self

Makes a clone of this shared reference.

This increments the strong reference count of the object. Dropping the object will decrement it again.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Object

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Object

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl HasParamSpec for Object

type ParamSpec = ParamSpecObject

type SetValue = Object

Preferred value to be used as setter for the associated ParamSpec.

type BuilderFn = fn(_: &str) -> ParamSpecObjectBuilder<'_, Object>

fn param_spec_builder() -> Self::BuilderFn

impl Hash for Object

fn hash<H>(&self, state: &mut H)

where H: Hasher,

Hashes the memory address of this object.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T: GstObjectImpl> IsSubclassable<T> for Object

fn class_init(class: &mut Class<Self>)

Override the virtual methods of this class for the given subclass and do other class initialization.

fn instance_init(instance: &mut InitializingObject<T>)

Instance specific initialization.

impl Ord for Object

fn cmp(&self, other: &Self) -> Ordering

Comparison for two GObjects.

Compares the memory addresses of the provided objects.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl ParentClassIs for Object

type Parent = Object

impl<OT: ObjectType> PartialEq<OT> for Object

fn eq(&self, other: &OT) -> bool

Equality for two GObjects.

Two GObjects are equal if their memory addresses are equal.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<OT: ObjectType> PartialOrd<OT> for Object

fn partial_cmp(&self, other: &OT) -> Option<Ordering>

Partial comparison for two GObjects.

Compares the memory addresses of the provided objects.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for Object

fn static_type() -> Type

Returns the type identifier of Self.

impl Eq for Object

impl IsA<Object> for Allocator

impl IsA<Object> for Bin

impl IsA<Object> for BufferPool

impl IsA<Object> for Bus

impl IsA<Object> for Clock

impl IsA<Object> for ControlBinding

impl IsA<Object> for ControlSource

impl IsA<Object> for Device

impl IsA<Object> for DeviceMonitor

impl IsA<Object> for DeviceProvider

impl IsA<Object> for DeviceProviderFactory

impl IsA<Object> for Element

impl IsA<Object> for ElementFactory

impl IsA<Object> for GhostPad

impl IsA<Object> for Pad

impl IsA<Object> for PadTemplate

impl IsA<Object> for Pipeline

impl IsA<Object> for Plugin

impl IsA<Object> for PluginFeature

impl IsA<Object> for ProxyPad

impl IsA<Object> for Registry

impl IsA<Object> for Stream

impl IsA<Object> for StreamCollection

impl IsA<Object> for SystemClock

impl IsA<Object> for TagSetter

impl IsA<Object> for Task

impl IsA<Object> for TaskPool

impl IsA<Object> for TocSetter

impl IsA<Object> for Tracer

impl IsA<Object> for TracerFactory

impl IsA<Object> for TypeFindFactory

impl Send for Object

impl Sync for Object