Struct gstreamer_base::Aggregator

source ·

pub struct Aggregator { /* private fields */ }

Expand description

Manages a set of pads with the purpose of aggregating their buffers. Control is given to the subclass when all pads have data.

Base class for mixers and muxers. Subclasses should at least implement the GstAggregatorClass::aggregate virtual method.
Installs a GstPadChainFunction, a GstPadEventFullFunction and a GstPadQueryFunction to queue all serialized data packets per sink pad. Subclasses should not overwrite those, but instead implement GstAggregatorClass::sink_event and GstAggregatorClass::sink_query as needed.
When data is queued on all pads, the aggregate vmethod is called.
One can peek at the data on any given GstAggregatorPad with the AggregatorPadExt::peek_buffer() method, and remove it from the pad with the gst_aggregator_pad_pop_buffer () method. When a buffer has been taken with pop_buffer (), a new buffer can be queued on that pad.
When AggregatorPadExt::peek_buffer() or AggregatorPadExt::has_buffer() are called, a reference is taken to the returned buffer, which stays valid until either:

AggregatorPadExt::pop_buffer() is called, in which case the caller is guaranteed that the buffer they receive is the same as the peeked buffer.
AggregatorPadExt::drop_buffer() is called, in which case the caller is guaranteed that the dropped buffer is the one that was peeked.
the subclass implementation of GstAggregatorClass.aggregate returns.

Subsequent calls to AggregatorPadExt::peek_buffer() or AggregatorPadExt::has_buffer() return / check the same buffer that was returned / checked, until one of the conditions listed above is met.

Subclasses are only allowed to call these methods from the aggregate thread.

If the subclass wishes to push a buffer downstream in its aggregate implementation, it should do so through the AggregatorExt::finish_buffer() method. This method will take care of sending and ordering mandatory events such as stream start, caps and segment. Buffer lists can also be pushed out with AggregatorExt::finish_buffer_list().
Same goes for EOS events, which should not be pushed directly by the subclass, it should instead return GST_FLOW_EOS in its aggregate implementation.
Note that the aggregator logic regarding gap event handling is to turn these into gap buffers with matching PTS and duration. It will also flag these buffers with GST_BUFFER_FLAG_GAP and GST_BUFFER_FLAG_DROPPABLE to ease their identification and subsequent processing. In addition, if the gap event was flagged with GST_GAP_FLAG_MISSING_DATA, a custom meta is added to the resulting gap buffer (GstAggregatorMissingDataMeta).
Subclasses must use (a subclass of) AggregatorPad for both their sink and source pads. See gst_element_class_add_static_pad_template_with_gtype().

This class used to live in gst-plugins-bad and was moved to core.

This is an Abstract Base Class, you cannot instantiate it.

§Properties

§`emit-signals`

Enables the emission of signals such as samples-selected

Readable | Writeable

§`latency`

Readable | Writeable

§`min-upstream-latency`

Force minimum upstream latency (in nanoseconds). When sources with a higher latency are expected to be plugged in dynamically after the aggregator has started playing, this allows overriding the minimum latency reported by the initial source(s). This is only taken into account when larger than the actually reported minimum latency.

Readable | Writeable

§`start-time`

Readable | Writeable

§`start-time-selection`

Readable | Writeable

Object

§`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 GstBin::element-added or GstBin::element-removed signals on the parent to achieve a similar effect.

Readable | Writeable

§Signals

§`samples-selected`

Signals that the Aggregator subclass has selected the next set of input samples it will aggregate. Handlers may call AggregatorExt::peek_next_sample() at that point.

Element

§`no-more-pads`

This signals that the element will not generate more dynamic pads. Note that this signal will usually be emitted from the context of the streaming thread.

§`pad-added`

a new gst::Pad has been added to the element. Note that this signal will usually be emitted from the context of the streaming thread. Also keep in mind that if you add new elements to the pipeline in the signal handler you will need to set them to the desired target state with [ElementExtManual::set_state()][crate::gst::prelude::ElementExtManual::set_state()] or [ElementExtManual::sync_state_with_parent()][crate::gst::prelude::ElementExtManual::sync_state_with_parent()].

§`pad-removed`

a gst::Pad has been removed from the element

Object

§`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

AggregatorExt, gst::prelude::ElementExt, gst::prelude::ObjectExt, [trait@glib::ObjectExt], AggregatorExtManual

GLib type: GObject with reference counted clone semantics.

Struct gstreamer_base::AggregatorCopy item path

§Properties

§emit-signals

§latency

§min-upstream-latency

§start-time

§start-time-selection

Object

§name

§parent

§Signals

§samples-selected

Element

§no-more-pads

§pad-added

§pad-removed

Object

§deep-notify

§Implements

Implementations§

impl Aggregator

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

Trait Implementations§

impl Clone for Aggregator

fn clone(&self) -> Self

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

impl Debug for Aggregator

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

impl HasParamSpec for Aggregator

type ParamSpec = ParamSpecObject

type SetValue = Aggregator

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

fn param_spec_builder() -> Self::BuilderFn

impl Hash for Aggregator

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

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

impl<T: AggregatorImpl> IsSubclassable<T> for Aggregator

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

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

impl Ord for Aggregator

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

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

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

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd,

impl ParentClassIs for Aggregator

type Parent = Element

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

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

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

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

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

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

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

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

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

impl StaticType for Aggregator

fn static_type() -> Type

impl Eq for Aggregator

impl IsA<Element> for Aggregator

impl IsA<Object> for Aggregator

impl Send for Aggregator

impl Sync for Aggregator

Auto Trait Implementations§

impl Freeze for Aggregator

impl RefUnwindSafe for Aggregator

impl Unpin for Aggregator

impl UnwindSafe for Aggregator

Blanket Implementations§

impl<O> AggregatorExt for Owhere O: IsA<Aggregator>,

fn finish_buffer(&self, buffer: Buffer) -> Result<FlowSuccess, FlowError>

fn finish_buffer_list( &self, bufferlist: BufferList, ) -> Result<FlowSuccess, FlowError>

fn buffer_pool(&self) -> Option<BufferPool>

fn is_force_live(&self) -> bool

fn ignores_inactive_pads(&self) -> bool

fn latency(&self) -> Option<ClockTime>

fn negotiate(&self) -> bool

fn peek_next_sample(&self, pad: &impl IsA<AggregatorPad>) -> Option<Sample>

fn set_force_live(&self, force_live: bool)

fn set_ignore_inactive_pads(&self, ignore: bool)

fn set_latency( &self, min_latency: ClockTime, max_latency: impl Into<Option<ClockTime>>, )

Struct gstreamer_base::Aggregator

§`emit-signals`

§`latency`

§`min-upstream-latency`

§`start-time`

§`start-time-selection`

§`name`

§`parent`

§`samples-selected`

§`no-more-pads`

§`pad-added`

§`pad-removed`

§`deep-notify`

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

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

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

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

fn clamp(self, min: Self, max: Self) -> Self
where Self: Sized + PartialOrd,

impl<O> AggregatorExt for O
where O: IsA<Aggregator>,

impl<O> AggregatorExtManual for O
where O: IsA<Aggregator>,

impl<T> Any for T
where T: 'static + ?Sized,

impl<T> Borrow<T> for T
where T: ?Sized,

impl<T> BorrowMut<T> for T
where T: ?Sized,

impl<T> Cast for T
where T: ObjectType,

fn upcast<T>(self) -> T
where T: ObjectType, Self: IsA<T>,

fn upcast_ref<T>(&self) -> &T
where T: ObjectType, Self: IsA<T>,

fn downcast<T>(self) -> Result<T, Self>
where T: ObjectType, Self: MayDowncastTo<T>,

fn downcast_ref<T>(&self) -> Option<&T>
where T: ObjectType, Self: MayDowncastTo<T>,

fn dynamic_cast<T>(self) -> Result<T, Self>
where T: ObjectType,

fn dynamic_cast_ref<T>(&self) -> Option<&T>
where T: ObjectType,

unsafe fn unsafe_cast<T>(self) -> T
where T: ObjectType,

unsafe fn unsafe_cast_ref<T>(&self) -> &T
where T: ObjectType,

impl<T> CloneToUninit for T
where T: Clone,

impl<O> ElementExt for O
where O: IsA<Element>,

fn foreach_pad<P>(&self, func: P) -> bool
where P: FnMut(&Element, &Pad) -> bool,

fn foreach_sink_pad<P>(&self, func: P) -> bool
where P: FnMut(&Element, &Pad) -> bool,

fn foreach_src_pad<P>(&self, func: P) -> bool
where P: FnMut(&Element, &Pad) -> bool,