fluvie_cli 0.1.3

Headless renderer CLI for Fluvie compositions: capture frames with flutter test, then encode with ffmpeg.

fluvie_cli

The headless renderer for Fluvie compositions. It captures frames with flutter test (software rendering, no display needed), then encodes them with FFmpeg into a real video file.

Install

dart pub global activate fluvie_cli

You also need FFmpeg on your PATH.

Render

fluvie render <composition> --out video.mp4

Useful options:

• --out <file>: the output path (required).
• --format <mp4|gif|imageSequence|transparent>: the export format.
• --quality <low|medium|high|max>: the encode quality.
• --aspect <...>: render a composition at another aspect ratio.
• --poster <time>: also write a poster frame (for example 1.5s, 30f).
• --frames <n>: capture only the first N frames (fast draft renders).
• --no-cache, --keep-temp, --verbose: caching and debugging controls.

Run fluvie render --help for the full list.

Generate from a prompt

With the companion fluvie_ai package, the CLI writes a video from natural language and renders it in one step. Set a provider and key first:

export FLUVIE_AI_PROVIDER=claude   # or gemini, mistral, ollama
export ANTHROPIC_API_KEY=sk-...

fluvie generate "a 6s vertical title card, dark gradient, fade-in headline" \
  --out promo.mp4 --spec-out promo.fluvie.json

Refine a saved spec; on an edit the current frame is sent to a multimodal model:

fluvie edit promo.fluvie.json "make the headline yellow" --out promo.mp4

Render a spec file directly, with no model call:

fluvie render --spec promo.fluvie.json --out promo.mp4

The .fluvie.json is the reproducible artifact: re-rendering it is always byte-identical. See the authoring guide.

Determinism

The same composition renders byte-identical frames every time. FFmpeg is always invoked with an argument list (never a shell string) and bitexact flags, so re-rendering reproduces the same output on the same machine.

Documentation

See the Fluvie exporting guide.

License

MIT. See LICENSE.