Struct gstreamer::event::Event

pub struct Event(_);

Methods

impl Event

pub unsafe fn from_glib_none(ptr: *const GstEvent) -> Self

pub unsafe fn from_glib_full(ptr: *const GstEvent) -> Self

pub unsafe fn from_glib_borrow(ptr: *const GstEvent) -> Self

pub unsafe fn into_ptr(self) -> *mut GstEvent

pub fn copy(&self) -> Self

impl Event

pub fn new_flush_start<'a>() -> FlushStartBuilder<'a>

Allocate a new flush start event. The flush start event can be sent upstream and downstream and travels out-of-bounds with the dataflow.

It marks pads as being flushing and will make them return FlowReturn::Flushing when used for data flow with Pad::push, Pad::chain, Pad::get_range and Pad::pull_range. Any event (except a EventType::FlushStop) received on a flushing pad will return false immediately.

Elements should unlock any blocking functions and exit their streaming functions as fast as possible when this event is received.

This event is typically generated after a seek to flush out all queued data in the pipeline so that the new media is played as soon as possible.

Returns

a new flush start event.

pub fn new_flush_stop<'a>(reset_time: bool) -> FlushStopBuilder<'a>

Allocate a new flush stop event. The flush stop event can be sent upstream and downstream and travels serialized with the dataflow. It is typically sent after sending a FLUSH_START event to make the pads accept data again.

Elements can process this event synchronized with the dataflow since the preceding FLUSH_START event stopped the dataflow.

This event is typically generated to complete a seek and to resume dataflow.

reset_time

if time should be reset

Returns

a new flush stop event.

pub fn new_stream_start(stream_id: &str) -> StreamStartBuilder

Create a new STREAM_START event. The stream start event can only travel downstream synchronized with the buffer flow. It is expected to be the first event that is sent for a new stream.

Source elements, demuxers and other elements that create new streams are supposed to send this event as the first event of a new stream. It should not be sent after a flushing seek or in similar situations and is used to mark the beginning of a new logical stream. Elements combining multiple streams must ensure that this event is only forwarded downstream once and not for every single input stream.

The stream_id should be a unique string that consists of the upstream stream-id, / as separator and a unique stream-id for this specific stream. A new stream-id should only be created for a stream if the upstream stream is split into (potentially) multiple new streams, e.g. in a demuxer, but not for every single element in the pipeline. PadExt::create_stream_id or PadExt::create_stream_id_printf can be used to create a stream-id. There are no particular semantics for the stream-id, though it should be deterministic (to support stream matching) and it might be used to order streams (besides any information conveyed by stream flags).

stream_id

Identifier for this stream

Returns

the new STREAM_START event.

pub fn new_caps(caps: &Caps) -> CapsBuilder

Create a new CAPS event for caps. The caps event can only travel downstream synchronized with the buffer flow and contains the format of the buffers that will follow after the event.

caps

a Caps

Returns

the new CAPS event.

pub fn new_segment<F: FormattedValue>(
    segment: &FormattedSegment<F>
) -> SegmentBuilder

Create a new SEGMENT event for segment. The segment event can only travel downstream synchronized with the buffer flow and contains timing information and playback properties for the buffers that will follow.

The segment event marks the range of buffers to be processed. All data not within the segment range is not to be processed. This can be used intelligently by plugins to apply more efficient methods of skipping unneeded data. The valid range is expressed with the start and stop values.

The time value of the segment is used in conjunction with the start value to convert the buffer timestamps into the stream time. This is usually done in sinks to report the current stream_time. time represents the stream_time of a buffer carrying a timestamp of start. time cannot be -1.

start cannot be -1, stop can be -1. If there is a valid stop given, it must be greater or equal the start, including when the indicated playback rate is < 0.

The applied_rate value provides information about any rate adjustment that has already been made to the timestamps and content on the buffers of the stream. (rate * applied_rate) should always equal the rate that has been requested for playback. For example, if an element has an input segment with intended playback rate of 2.0 and applied_rate of 1.0, it can adjust incoming timestamps and buffer content by half and output a segment event with rate of 1.0 and applied_rate of 2.0

After a segment event, the buffer stream time is calculated with:

time + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)

segment

a Segment

Returns

the new SEGMENT event.

pub fn new_stream_collection(
    stream_collection: &StreamCollection
) -> StreamCollectionBuilder

Create a new STREAM_COLLECTION event. The stream collection event can only travel downstream synchronized with the buffer flow.

Source elements, demuxers and other elements that manage collections of streams and post StreamCollection messages on the bus also send this event downstream on each pad involved in the collection, so that activation of a new collection can be tracked through the downstream data flow.

Feature: v1_10

collection

Active collection for this data flow

Returns

the new STREAM_COLLECTION event.

pub fn new_tag<'a>(tags: TagList) -> TagBuilder<'a>

Generates a metadata tag event from the given taglist.

The scope of the taglist specifies if the taglist applies to the complete medium or only to this specific stream. As the tag event is a sticky event, elements should merge tags received from upstream with a given scope with their own tags with the same scope and create a new tag event from it.

taglist

metadata list. The event will take ownership of the taglist.

Returns

a new Event

pub fn new_buffer_size<'a, V: Into<GenericFormattedValue>>(
    minsize: V,
    maxsize: V,
    async: bool
) -> BufferSizeBuilder<'a>

Create a new buffersize event. The event is sent downstream and notifies elements that they should provide a buffer of the specified dimensions.

When the async flag is set, a thread boundary is preferred.

format

buffer format

minsize

minimum buffer size

maxsize

maximum buffer size

async

thread behavior

Returns

a new Event

pub fn new_sink_message<'a>(
    name: &'a str,
    msg: &'a Message
) -> SinkMessageBuilder<'a>

Create a new sink-message event. The purpose of the sink-message event is to instruct a sink to post the message contained in the event synchronized with the stream.

name is used to store multiple sticky events on one pad.

name

a name for the event

msg

the Message to be posted

Returns

a new Event

pub fn new_stream_group_done<'a>(
    group_id: GroupId
) -> StreamGroupDoneBuilder<'a>

Create a new Stream Group Done event. The stream-group-done event can only travel downstream synchronized with the buffer flow. Elements that receive the event on a pad should handle it mostly like EOS, and emit any data or pending buffers that would depend on more data arriving and unblock, since there won't be any more data.

This event is followed by EOS at some point in the future, and is generally used when switching pads - to unblock downstream so that new pads can be exposed before sending EOS on the existing pads.

Feature: v1_10

group_id

the group id of the stream group which is ending

Returns

the new stream-group-done event.

pub fn new_eos<'a>() -> EosBuilder<'a>

Create a new EOS event. The eos event can only travel downstream synchronized with the buffer flow. Elements that receive the EOS event on a pad can return FlowReturn::Eos as a FlowReturn when data after the EOS event arrives.

The EOS event will travel down to the sink elements in the pipeline which will then post the MessageType::Eos on the bus after they have finished playing any buffered data.

When all sinks have posted an EOS message, an EOS message is forwarded to the application.

The EOS event itself will not cause any state transitions of the pipeline.

Returns

the new EOS event.

pub fn new_toc(toc: &Toc, updated: bool) -> TocBuilder

Generate a TOC event from the given toc. The purpose of the TOC event is to inform elements that some kind of the TOC was found.

toc

Toc structure.

updated

whether toc was updated or not.

Returns

a new Event.

pub fn new_protection<'a>(
    system_id: &'a str,
    data: &'a Buffer
) -> ProtectionBuilder<'a>

Creates a new event containing information specific to a particular protection system (uniquely identified by system_id), by which that protection system can acquire key(s) to decrypt a protected stream.

In order for a decryption element to decrypt media protected using a specific system, it first needs all the protection system specific information necessary to acquire the decryption key(s) for that stream. The functions defined here enable this information to be passed in events from elements that extract it (e.g., ISOBMFF demuxers, MPEG DASH demuxers) to protection decrypter elements that use it.

Events containing protection system specific information are created using Event::new_protection, and they can be parsed by downstream elements using Event::parse_protection.

In Common Encryption, protection system specific information may be located within ISOBMFF files, both in movie (moov) boxes and movie fragment (moof) boxes; it may also be contained in ContentProtection elements within MPEG DASH MPDs. The events created by Event::new_protection contain data identifying from which of these locations the encapsulated protection system specific information originated. This origin information is required as some protection systems use different encodings depending upon where the information originates.

The events returned by Event::new_protection are implemented in such a way as to ensure that the most recently-pushed protection info event of a particular origin and system_id will be stuck to the output pad of the sending element.

system_id

a string holding a UUID that uniquely identifies a protection system.

data

a Buffer holding protection system specific information. The reference count of the buffer will be incremented by one.

origin

a string indicating where the protection information carried in the event was extracted from. The allowed values of this string will depend upon the protection scheme.

Returns

a EventType::Protection event, if successful; None if unsuccessful.

pub fn new_segment_done<'a, V: Into<GenericFormattedValue>>(
    position: V
) -> SegmentDoneBuilder<'a>

Create a new segment-done event. This event is sent by elements that finish playback of a segment as a result of a segment seek.

format

The format of the position being done

position

The position of the segment being done

Returns

a new Event

pub fn new_gap<'a>(timestamp: ClockTime, duration: ClockTime) -> GapBuilder<'a>

Create a new GAP event. A gap event can be thought of as conceptually equivalent to a buffer to signal that there is no data for a certain amount of time. This is useful to signal a gap to downstream elements which may wait for data, such as muxers or mixers or overlays, especially for sparse streams such as subtitle streams.

timestamp

the start time (pts) of the gap

duration

the duration of the gap

Returns

the new GAP event.

pub fn new_qos<'a>(
    type_: QOSType,
    proportion: f64,
    diff: i64,
    timestamp: ClockTime
) -> QosBuilder<'a>

Allocate a new qos event with the given values. The QOS event is generated in an element that wants an upstream element to either reduce or increase its rate because of high/low CPU load or other resource usage such as network performance or throttling. Typically sinks generate these events for each buffer they receive.

type_ indicates the reason for the QoS event. QOSType::Overflow is used when a buffer arrived in time or when the sink cannot keep up with the upstream datarate. QOSType::Underflow is when the sink is not receiving buffers fast enough and thus has to drop late buffers. QOSType::Throttle is used when the datarate is artificially limited by the application, for example to reduce power consumption.

proportion indicates the real-time performance of the streaming in the element that generated the QoS event (usually the sink). The value is generally computed based on more long term statistics about the streams timestamps compared to the clock. A value < 1.0 indicates that the upstream element is producing data faster than real-time. A value > 1.0 indicates that the upstream element is not producing data fast enough. 1.0 is the ideal proportion value. The proportion value can safely be used to lower or increase the quality of the element.

diff is the difference against the clock in running time of the last buffer that caused the element to generate the QOS event. A negative value means that the buffer with timestamp arrived in time. A positive value indicates how late the buffer with timestamp was. When throttling is enabled, diff will be set to the requested throttling interval.

timestamp is the timestamp of the last buffer that cause the element to generate the QOS event. It is expressed in running time and thus an ever increasing value.

The upstream element can use the diff and timestamp values to decide whether to process more buffers. For positive diff, all buffers with timestamp <= timestamp + diff will certainly arrive late in the sink as well. A (negative) diff value so that timestamp + diff would yield a result smaller than 0 is not allowed.

The application can use general event probes to intercept the QoS event and implement custom application specific QoS handling.

type_

the QoS type

proportion

the proportion of the qos message

diff

The time difference of the last Clock sync

timestamp

The timestamp of the buffer

Returns

a new QOS event.

pub fn new_seek<'a, V: Into<GenericFormattedValue>>(
    rate: f64,
    flags: SeekFlags,
    start_type: SeekType,
    start: V,
    stop_type: SeekType,
    stop: V
) -> SeekBuilder<'a>

Allocate a new seek event with the given parameters.

The seek event configures playback of the pipeline between start to stop at the speed given in rate, also called a playback segment. The start and stop values are expressed in format.

A rate of 1.0 means normal playback rate, 2.0 means double speed. Negatives values means backwards playback. A value of 0.0 for the rate is not allowed and should be accomplished instead by PAUSING the pipeline.

A pipeline has a default playback segment configured with a start position of 0, a stop position of -1 and a rate of 1.0. The currently configured playback segment can be queried with QueryType::Segment.

start_type and stop_type specify how to adjust the currently configured start and stop fields in playback segment. Adjustments can be made relative or absolute to the last configured values. A type of SeekType::None means that the position should not be updated.

When the rate is positive and start has been updated, playback will start from the newly configured start position.

For negative rates, playback will start from the newly configured stop position (if any). If the stop position is updated, it must be different from -1 (GST_CLOCK_TIME_NONE) for negative rates.

It is not possible to seek relative to the current playback position, to do this, PAUSE the pipeline, query the current playback position with QueryType::Position and update the playback segment current position with a SeekType::Set to the desired position.

rate

The new playback rate

format

The format of the seek values

flags

The optional seek flags

start_type

The type and flags for the new start position

start

The value of the new start position

stop_type

The type and flags for the new stop position

stop

The value of the new stop position

Returns

a new seek event.

pub fn new_navigation<'a>(structure: Structure) -> NavigationBuilder<'a>

Create a new navigation event from the given description.

structure

description of the event. The event will take ownership of the structure.

Returns

a new Event

pub fn new_latency<'a>(latency: ClockTime) -> LatencyBuilder<'a>

Create a new latency event. The event is sent upstream from the sinks and notifies elements that they should add an additional latency to the running time before synchronising against the clock.

The latency is mostly used in live sinks and is always expressed in the time format.

latency

the new latency value

Returns

a new Event

pub fn new_step<'a, V: Into<GenericFormattedValue>>(
    amount: V,
    rate: f64,
    flush: bool,
    intermediate: bool
) -> StepBuilder<'a>

Create a new step event. The purpose of the step event is to instruct a sink to skip amount (expressed in format) of media. It can be used to implement stepping through the video frame by frame or for doing fast trick modes.

A rate of <= 0.0 is not allowed. Pause the pipeline, for the effect of rate = 0.0 or first reverse the direction of playback using a seek event to get the same effect as rate < 0.0.

The flush flag will clear any pending data in the pipeline before starting the step operation.

The intermediate flag instructs the pipeline that this step operation is part of a larger step operation.

format

the format of amount

amount

the amount of data to step

rate

the step rate

flush

flushing steps

intermediate

intermediate steps

Returns

a new Event

pub fn new_reconfigure<'a>() -> ReconfigureBuilder<'a>

Create a new reconfigure event. The purpose of the reconfigure event is to travel upstream and make elements renegotiate their caps or reconfigure their buffer pools. This is useful when changing properties on elements or changing the topology of the pipeline.

Returns

a new Event

pub fn new_toc_select(uid: &str) -> TocSelectBuilder

Generate a TOC select event with the given uid. The purpose of the TOC select event is to start playback based on the TOC's entry with the given uid.

uid

UID in the TOC to start playback from.

Returns

a new Event.

pub fn new_select_streams<'a>(
    streams: &'a [&'a str]
) -> SelectStreamsBuilder<'a>

Allocate a new select-streams event.

The select-streams event requests the specified streams to be activated.

The list of streams corresponds to the "Stream ID" of each stream to be activated. Those ID can be obtained via the Stream objects present in EventType::StreamStart, EventType::StreamCollection or MessageType::StreamCollection.

Note: The list of streams can not be empty.

Feature: v1_10

streams

the list of streams to activate

Returns

a new select-streams event or None in case of an error (like an empty streams list).

pub fn new_custom_upstream<'a>(
    structure: Structure
) -> CustomUpstreamBuilder<'a>

pub fn new_custom_downstream<'a>(
    structure: Structure
) -> CustomDownstreamBuilder<'a>

pub fn new_custom_downstream_oob<'a>(
    structure: Structure
) -> CustomDownstreamOobBuilder<'a>

pub fn new_custom_downstream_sticky<'a>(
    structure: Structure
) -> CustomDownstreamStickyBuilder<'a>

pub fn new_custom_both<'a>(structure: Structure) -> CustomBothBuilder<'a>

pub fn new_custom_both_oob<'a>(structure: Structure) -> CustomBothOobBuilder<'a>

Methods from Deref<Target = GstRc<EventRef>>

pub fn make_mut(&mut self) -> &mut T

pub fn get_mut(&mut self) -> Option<&mut T>

pub fn is_writable(&self) -> bool

pub fn add_parent<U: MiniObject>(&self, parent: &U)

pub fn remove_parent<U: MiniObject>(&self, parent: &U)

Trait Implementations

impl AsRef<EventRef> for Event

fn as_ref(&self) -> &EventRef

Performs the conversion.

impl Borrow<EventRef> for Event

fn borrow(&self) -> &EventRef

Immutably borrows from an owned value.

impl Clone for Event

fn clone(&self) -> Event

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Event

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

Formats the value using the given formatter.

impl Deref for Event

type Target = GstRc<EventRef>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl DerefMut for Event

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl From<GstRc<EventRef>> for Event

fn from(rc: GstRc<EventRef>) -> Event

Performs the conversion.

impl FromGlibContainerAsVec<*mut GstEvent, *const *mut GstEvent> for Event

unsafe fn from_glib_none_num_as_vec(
    ptr: *const *mut GstEvent,
    num: usize
) -> Vec<Self>

unsafe fn from_glib_container_num_as_vec(
    _: *const *mut GstEvent,
    _: usize
) -> Vec<Self>

unsafe fn from_glib_full_num_as_vec(
    _: *const *mut GstEvent,
    _: usize
) -> Vec<Self>

impl FromGlibContainerAsVec<*mut GstEvent, *mut *mut GstEvent> for Event

unsafe fn from_glib_none_num_as_vec(
    ptr: *mut *mut GstEvent,
    num: usize
) -> Vec<Self>

unsafe fn from_glib_container_num_as_vec(
    ptr: *mut *mut GstEvent,
    num: usize
) -> Vec<Self>

unsafe fn from_glib_full_num_as_vec(
    ptr: *mut *mut GstEvent,
    num: usize
) -> Vec<Self>

impl FromGlibPtrArrayContainerAsVec<*mut GstEvent, *const *mut GstEvent> for Event

unsafe fn from_glib_none_as_vec(ptr: *const *mut GstEvent) -> Vec<Self>

unsafe fn from_glib_container_as_vec(_: *const *mut GstEvent) -> Vec<Self>

unsafe fn from_glib_full_as_vec(_: *const *mut GstEvent) -> Vec<Self>

impl FromGlibPtrArrayContainerAsVec<*mut GstEvent, *mut *mut GstEvent> for Event

unsafe fn from_glib_none_as_vec(ptr: *mut *mut GstEvent) -> Vec<Self>

unsafe fn from_glib_container_as_vec(ptr: *mut *mut GstEvent) -> Vec<Self>

unsafe fn from_glib_full_as_vec(ptr: *mut *mut GstEvent) -> Vec<Self>

impl FromGlibPtrBorrow<*const GstEvent> for Event

unsafe fn from_glib_borrow(ptr: *const GstEvent) -> Self

impl FromGlibPtrBorrow<*mut GstEvent> for Event

unsafe fn from_glib_borrow(ptr: *mut GstEvent) -> Self

impl FromGlibPtrFull<*const GstEvent> for Event

unsafe fn from_glib_full(ptr: *const GstEvent) -> Self

impl FromGlibPtrFull<*mut GstEvent> for Event

unsafe fn from_glib_full(ptr: *mut GstEvent) -> Self

impl FromGlibPtrNone<*const GstEvent> for Event

unsafe fn from_glib_none(ptr: *const GstEvent) -> Self

impl FromGlibPtrNone<*mut GstEvent> for Event

unsafe fn from_glib_none(ptr: *mut GstEvent) -> Self

impl<'a> FromValueOptional<'a> for Event

unsafe fn from_value_optional(v: &'a Value) -> Option<Self>

impl GlibPtrDefault for Event

type GlibType = *mut GstEvent

impl Into<GstRc<EventRef>> for Event

fn into(self) -> GstRc<EventRef>

Performs the conversion.

impl SetValue for Event

unsafe fn set_value(v: &mut Value, s: &Self)

impl SetValueOptional for Event

unsafe fn set_value_optional(v: &mut Value, s: Option<&Self>)

impl StaticType for Event

fn static_type() -> Type

Returns the type identifier of Self.

impl<'a> ToGlibContainerFromSlice<'a, *const *mut GstEvent> for Event

type Storage = (Vec<Stash<'a, *mut GstEvent, Event>>, Option<Vec<*mut GstEvent>>)

fn to_glib_none_from_slice(
    t: &'a [Event]
) -> (*const *mut GstEvent, Self::Storage)

fn to_glib_container_from_slice(
    _: &'a [Event]
) -> (*const *mut GstEvent, Self::Storage)

fn to_glib_full_from_slice(_: &[Event]) -> *const *mut GstEvent

impl<'a> ToGlibContainerFromSlice<'a, *mut *mut GstEvent> for Event

type Storage = (Vec<Stash<'a, *mut GstEvent, Event>>, Option<Vec<*mut GstEvent>>)

fn to_glib_none_from_slice(
    t: &'a [Event]
) -> (*mut *mut GstEvent, Self::Storage)

fn to_glib_container_from_slice(
    t: &'a [Event]
) -> (*mut *mut GstEvent, Self::Storage)

fn to_glib_full_from_slice(t: &[Event]) -> *mut *mut GstEvent

impl<'a> ToGlibPtr<'a, *const GstEvent> for Event

type Storage = Stash<'a, *const GstEvent, GstRc<EventRef>>

fn to_glib_none(&'a self) -> Stash<'a, *const GstEvent, Self>

Transfer: none.

fn to_glib_full(&self) -> *const GstEvent

Transfer: full.

fn to_glib_container(&'a self) -> Stash<'a, P, Self>

Transfer: container.

impl<'a> ToGlibPtr<'a, *mut GstEvent> for Event

type Storage = Stash<'a, *mut GstEvent, GstRc<EventRef>>

fn to_glib_none(&'a self) -> Stash<'a, *mut GstEvent, Self>

Transfer: none.

fn to_glib_full(&self) -> *mut GstEvent

Transfer: full.

fn to_glib_container(&'a self) -> Stash<'a, P, Self>

Transfer: container.

impl<'a> ToGlibPtrMut<'a, *mut GstEvent> for Event

type Storage = StashMut<'a, *mut GstEvent, GstRc<EventRef>>

fn to_glib_none_mut(&'a mut self) -> StashMut<*mut GstEvent, Self>

Transfer: none.