Module scene 

Real-time playback of a Scene.

ScenePlayer opens every placement on the base video track of a Scene and plays them back in order, mapping each clip’s frame PTS to the unified timeline coordinate. The Scene is a model-agnostic description an engine derives from its editing model.

Type	Role
ScenePlayer	Thin builder: call open
SceneRunner	Owns the decode pipelines; move to a thread and call run
PlayerHandle	Shared, cloneable control handle

Audio

When any placement on the base video track carries an audio stream, ScenePlayer::open creates an AudioMixer with one track per audio-bearing clip. A background AudioDecoder thread is started for the active clip and pushes mono samples via AudioTrackHandle. On clip transition or seek the old thread is cancelled and a new one is started. PlayerHandle::pop_audio_samples calls AudioMixer::mix and returns interleaved stereo f32 output.

Structs

Scene

A whole timeline’s worth of playback work, described without the editing model.

SceneAudioPlacement

One audio-only clip placed on the timeline.

SceneAudioTrack

One dedicated audio-only track (A1, A2, …).

ScenePlacement

One video clip placed on the timeline.

ScenePlayer

Thin builder for a (SceneRunner, PlayerHandle) pair backed by a Scene.

SceneRunner

Exclusive owner of the timeline decode pipeline.

SceneVideoTrack

One video track: an ordered list of clip placements along the timeline. The track’s index in Scene::video_tracks is its compositing order (0 = base).

Enums

Pacing

How SceneRunner::run paces frame delivery.

SceneSource

The video source backing a ScenePlacement: a decoded media file, or a generated (solid-colour / text) source rendered without a file — the preview counterpart of the engine’s ClipSource. Generated sources are produced by ff-filter’s SolidSource / TextSource (the same color / drawtext filters the export path uses), so preview matches export.

Traits

PreviewCompositor

An external compositor the preview runner can use in place of its built-in CPU compositor. Implemented by avio over ff-render; see the module docs.

Functions

apply_xfade

Blends the outgoing frame a and incoming frame b (packed RGBA, w*h*4) at transition progress alpha (0 = all A, 1 = all B) using the xfade kind.