Struct TestAudioSource 

pub struct TestAudioSource { /* private fields */ }

Generates a synthetic sine-wave tone — GStreamer’s audiotestsrc equivalent. No real capture device involved: TestAudioSource::run fabricates however many samples wall-clock time now owes on a drift-free absolute schedule (expected = elapsed * sample_rate, needed = expected - samples_emitted — the same shape WasapiCaptureSource::fill_silence_gap/AudioMixer::mix_tick both use, not a fixed per-tick sample count, which would drift the same way a fixed-duration thread::sleep-only schedule would), stamps it with an increasing pts (one sample per tick of TestAudioSource::time_base’s units), and pushes it straight downstream — useful for exercising AudioMixer/an encoder/a muxer without a real microphone.

Always emits Sample::F32(Packed) — the same fixed internal format AudioMixer mixes in, so this can feed a MixerHandle input directly with nothing to resample (though MixerInputSink resamples regardless if fed something else instead, so this isn’t load-bearing).

Runs until Stop — never reaches Eos on its own, same as every other live source in this crate (no sample-count limit is exposed, deliberately, mirroring a live capture source more than a file).

Implementations

impl TestAudioSource

pub fn new(name: impl Into<String>, options: TestAudioOptions) -> Self

Creates an unbounded synthetic sine-wave source with the requested output definition.

pub fn time_base(&self) -> Rational

The unit each emitted frame’s pts is expressed in.

Trait Implementations

impl Element for TestAudioSource

fn name(&self) -> Arc<str>

Returns a cheap clone (refcount bump, not a deep copy) of this element’s name — crate::bus::BusEvent stores names as Arc<str> for exactly this reason: a hot path like crate::queue::Queue posting BusEvent::Dropped once per overflowed buffer shouldn’t pay for a fresh heap allocation every time it wants to report which element it is.

fn element_type(&self) -> ElementType

See ElementType.

fn pp_log(&self) -> &PpLog

This element’s identity for crate::bus::Bus::post — same id/name as Element::name, just already wrapped as the crate::pp_log::PpLog its pp_info!/pp_warn!/pp_error! macros need. A stored private field, not built fresh per call, for the same reason name() returns a cheap Arc<str> clone instead of a fresh String — see its own docs.

fn pp_log_mut(&mut self) -> &mut PpLog

Mutable access to the same field Element::pp_log reads — used by crate::pipeline::ChainBuilder to stamp the owning crate::pipeline::Pipeline’s id onto every element that passes through it, via element_pp_log. Not meant to be called from anywhere else.

fn graph_id(&self) -> Option<ElementId>

A pre-reserved graph identity for elements that expose dynamic attachment handles. Most elements receive an ID from ChainBuilder and keep the default None implementation.

fn attach_context(&mut self, _context: &Arc<Context>)

Hands this element the pipeline it is being wired into, at the moment and for the reason Element::pp_log_mut hands it the pipeline’s identity: the clock, the playback clock and the bus are the pipeline’s to give, not the caller’s to choose.

impl Send for TestAudioSource

impl Source for TestAudioSource

fn src_pads(&mut self) -> &mut [SrcPad]

Returns every output pad owned by this element.

impl SourceElement for TestAudioSource

fn is_live(&self) -> bool

Whether this source produces data from a live, externally advancing input rather than from a finite or application-controlled timeline.

fn is_seekable(&self) -> bool

Whether this source can reposition its own input timeline through Self::seek.

fn run(&mut self, control: &ControlReceiver, bus: &Bus) -> Result<()>

Drives this source until Eos (normal completion), crate::pipeline::Pipeline::finish, or Stop (see ControlMsg::Stop) — call crate::control::drain_control once per loop iteration to make control responsive between blocking reads.

fn seek(&mut self, _target: Duration) -> Result<Duration>

Repositions this source to target, an absolute position from the start of the media (e.g. av_seek_frame for crate::elements::FileDemuxer). Called by crate::control::drain_control as part of handling ControlMsg::Seek, before that message is forwarded to the source’s own pads — so whatever’s read next comes from the new position by the time downstream elements receive the new timeline announcement. Buffered and stateful old-timeline data is discarded by the preceding ControlMsg::Flush.

fn on_control(&mut self, _msg: &ControlMsg)

Reacts to one control message before it is forwarded to this source’s own pads — the same ordering Self::seek gets, and for the same reason: whatever this source holds must already reflect the message by the time downstream elements see it.