Optional ReadonlyenabledPause playback while required artifacts are unprepared. A session turns
this on by default, so a preview opens with its annotations rather than
opening bare; playbackGate: false on the session turns it off. A renderer
created directly leaves it off.
Optional ReadonlyminimumPrepared lead that is enough not to start a wait at all. Defaults to
requiredAheadSeconds and is capped by it: playback stalls only below this
lead, and a stall then clears only once the lead reaches
requiredAheadSeconds. Setting it lower buys hysteresis, so a lead
hovering at the requirement does not stutter.
Optional ReadonlyrequiredPrepared lead a wait in progress must reach before an enabled gate lets playback continue. Defaults to none, which asks only that the frame about to be presented is no longer pending.
Prepared-artifact playback gate, off unless
enabledsays otherwise.Off, preparation runs behind the picture and a frame the prepared window does not cover reaches no annotation layer instead of holding playback back. On, playback waits until the prepared window leads the playhead, so masks and polygons arrive with their frame rather than after it.
The renderer can only hold a frame it is about to draw itself, so this gate reaches only a media source it pulls decoded samples from. A source that presents its own frames owns the playhead and paces itself; that is the video-engine source,
openVideoEngineMediaSourceand thecreateVideoEngineMediaRendererSourcewrapper around it, which is what most video sessions render through. On a source that presents its own frames this gate holds the start of playback and nothing after it: the wait runs once, before the producer is told to play, and the renderer reportsBufferingwhile it does. Once the producer is running, unprepared layers stay absent until preparation catches up.