Struct gstreamer_editing_services::BaseEffect

pub struct BaseEffect(_, _);

A BaseEffect is some operation that applies an effect to the data it receives.

Time Effects

Some operations will change the timing of the stream data they receive in some way. In particular, the gst::Element that they wrap could alter the times of the segment they receive in a gst::EventType::Segment event, or the times of a seek they receive in a gst::EventType::Seek event. Such operations would be considered time effects since they translate the times they receive on their source to different times at their sink, and vis versa. This introduces two sets of time coordinates for the event: (internal) sink coordinates and (internal) source coordinates, where segment times are translated from the sink coordinates to the source coordinates, and seek times are translated from the source coordinates to the sink coordinates.

If you use such an effect in GES, you will need to inform GES of the properties that control the timing with BaseEffectExt::register_time_property, and the effect's timing behaviour using BaseEffectExt::set_time_translation_funcs.

Note that a time effect should not have its TrackElement:has-internal-source set to true.

In addition, note that GES only fully supports time effects whose mapping from the source to sink coordinates (those applied to seeks) obeys:

• Maps the time 0 to 0. So initial time-shifting effects are excluded.
• Is monotonically increasing. So reversing effects, and effects that jump backwards in the stream are excluded.
• Can handle a reasonable gst::ClockTime, relative to the project. So this would exclude a time effect with an extremely large speed-up that would cause the converted gst::ClockTime seeks to overflow.
• Is 'continuously reversible'. This essentially means that for every time in the sink coordinates, we can, to 'good enough' accuracy, calculate the corresponding time in the source coordinates. Moreover, this should correspond to how segment times are translated from sink to source.
• Only depends on the registered time properties, rather than the state of the gst::Element or the data it receives. This would exclude, say, an effect that would speedup if there is more red in the image it receives.

Note that a constant-rate-change effect that is not extremely fast or slow would satisfy these conditions. For such effects, you may wish to use EffectClass::register_rate_property.

Implements

BaseEffectExt, TrackElementExt, TimelineElementExt, glib::object::ObjectExt, ExtractableExt, TimelineElementExtManual

Trait Implementations

impl Clone for BaseEffect

fn clone(&self) -> BaseEffect

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for BaseEffect

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

Formats the value using the given formatter.

impl Eq for BaseEffect

impl Hash for BaseEffect

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

Feeds this value into the given Hasher.

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

Feeds a slice of this type into the given Hasher.

impl IsA<BaseEffect> for Effect

impl IsA<Extractable> for BaseEffect

impl IsA<TimelineElement> for BaseEffect

impl IsA<TrackElement> for BaseEffect

impl Ord for BaseEffect

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

This method returns an Ordering between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl<T: ObjectType> PartialEq<T> for BaseEffect

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<T: ObjectType> PartialOrd<T> for BaseEffect

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

This method returns an ordering between self and other values if one exists.

#[must_use]fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]fn le(&self, other: &Rhs) -> bool

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

#[must_use]fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]fn ge(&self, other: &Rhs) -> bool

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

impl StaticType for BaseEffect

fn static_type() -> Type

Returns the type identifier of Self.