warmup method

Stream<WarmupProgress> warmup()

Perform any slow early initialisation required by this backend.

Common uses:

• Downloading FFmpeg shared libraries on first run.
• Fetching a remote ML model.
• Warming up a JIT or shader cache.

Emit WarmupProgress events as work proceeds. The stream must complete (fire onDone) when all work is done or has failed. Failures should be emitted as WarmupProgress events with a non-null WarmupProgress.error — the stream itself must not error.

The default implementation returns an empty stream (no warmup needed). Backends that need no early initialisation do not need to override this.

Implementation

Stream<WarmupProgress> warmup() => const Stream.empty();