Struct LavfiSource 

pub struct LavfiSource { /* private fields */ }

Generates video frames from an FFmpeg lavfi filtergraph string (e.g. color=s=1920x1080:c=black@0.0,drawtext=text='Title'), so a host such as the preview runner can feed a timeline-level generated overlay into a RealtimeComposer as pushed frames.

The output is rgba and preserves the graph’s own alpha (no canvas is composited underneath), matching the export path’s topmost lavfi layer. Frames are produced sequentially via pull; the source exposes no seek, so a host that seeks rebuilds it from scratch.

Implementations

impl LavfiSource

pub fn new(lavfi: &str) -> Result<Self, FilterError>

Builds a source from a lavfi filtergraph string.

Errors

Returns FilterError when the underlying FFmpeg graph cannot be built (e.g. the movie / lavfi demuxer is unavailable, or the string is invalid).

pub fn pull(&mut self) -> Result<Option<VideoFrame>, FilterError>

Pulls the next generated frame (rgba), or None when none is buffered yet or at end-of-stream.

Errors

Returns FilterError on an unexpected FFmpeg error.