Review a video before sharing it

Run one command to check the Dart source, inspect the mounted composition and capture representative pictures:

fluvie review lib/my_video.dart --json

Review executes your composition in the package-owned Flutter host. Use validate when you only want static diagnostics without running the code. The review report combines validation, actual mounted timing and resource facts, sample images and the paths needed to examine the result. It is useful to a human reviewer and to an assistant repairing a composition.

Inspect the report visually

Review writes index.html beside review.json. Open it locally to inspect the sample PNGs, diagnostics and provenance. The live authoring workspace adds exact-frame seeking, before/after comparison and export controls.

Review text and sound

Selected-frame review inspects laid-out Flutter paragraphs for overflow, declared windows too brief for the text, and requested fonts absent from the loaded font manifest. Findings include a frame or interval, a stable code, an explanation and a remedy. Reading time uses three whitespace-separated words per second plus 350 ms and is an advisory heuristic. Offstage and fully transparent subtrees are skipped. Custom painters and rasterized text are not inspected; font absence indicates portability risk rather than proven glyph substitution.

Caption reading windows use the individual cue’s interval, including when the caption layer spans the whole video. The live workspace lists each finding and its remedy; Inspect frame seeks to the finding on the reviewed source revision. A source edit makes that request fail explicitly until you review the new revision.

With --render, review also measures encoded audio. It reports silence below -50 dB lasting at least 500 ms and peaks at or above -0.05 dBFS. Near-full-scale peaks indicate clipping risk rather than proven distortion. These findings may be intentional. Missing measurement inputs are explicitly unchecked.

fluvie review lib/my_video.dart --render --strict-quality \
  --allow-quality audio_silence --json

Normal quality findings are advisory. --strict-quality fails on warnings not explicitly allowed. Allowed findings stay visible with their reason. Valid codes are text_overflow, text_too_brief, font_not_bundled, audio_silence and audio_peak. Other validation, determinism and output failures still fail review.

Strict quality also fails when an applicable encoded-audio measurement is unavailable. An export with no audio stream is explicitly inapplicable. Ordinary rendered reviews measure audio even without --strict-decode; that flag separately checks decodability. checksComplete records whether applicable measurements completed. Intentional finding exceptions never turn a failed measurement into a pass.

Choose the pictures to inspect

With no sample list, review selects representative positions. Use explicit authored frame indexes for a transition or problem area:

fluvie review lib/my_video.dart --samples 0,15,29 \
  --out-dir build/fluvie/review --json

Choose indexes within your video’s duration. Shared --project, entrypoint, tooling and output-option flags work as they do for rendering. The report keeps errors associated with their stage, resource and requested frame where available.

Check seeking and fresh initialization

fluvie review lib/my_video.dart --determinism --json

With the managed capture cache disabled, review hashes the selected RGBA pictures and performs two checks:

• same_session_reverse_seek captures the pictures in reverse order in the original session. It catches painted state that depends on seek history.
• fresh_mount unmounts the original tree, prepares a new session and captures the same pictures again. The managed adapter invokes your entry function again, so factory choices and widget initialization are checked. A custom host can pass videoFactory to runFluvieRender; without it, the same immutable video definition is remounted with fresh widget state.

The combined method is reverse_seek_and_fresh_mount. The report’s checks array gives separate outcomes and factoryEvaluated records whether the entry was invoked again. Mismatches carry a stable code, their check, an authored frame when applicable, expected/actual evidence and a remedy. Canvas, FPS and duration changes receive fresh_mount_changes_composition; pixel differences receive fresh_mount_changes_pixels. A factory or preparation failure receives fresh_mount_failed with its cause. Original sample PNGs remain available even when fresh preparation fails.

Review checks sampled frames in one host process. It does not reset process-wide globals, inspect every frame or guarantee identity across Flutter engines, platforms and fonts. Repeat independent renders when process initialization is part of your inputs. Static validation also warns about obvious SDK clock and unseeded random calls inside video construction through nondeterministic_video.

Render and verify the final output

fluvie review lib/my_video.dart --render --strict-decode --json

--render produces an encoded artifact and compares readable output facts to the resolved render intent, including audio-stream presence. A stream alone does not establish audible sound or a suitable level. --strict-decode also asks FFmpeg to decode the complete output so corruption after the container header does not pass a probe-only check. It requires --render and costs an additional decode. This verifies decodability. Verification does not judge the story, typography, framing or whether a picture is the one you intended; inspect the samples and watch the result for those decisions.

For automation, --json returns the review report as JSON. --machine writes JSON progress events followed by a final event: "review" report. The related inspect --machine and frame --machine commands finish with inspection and frame events; the frame event includes its index and output path.

Where to next

• Exporting your video: output settings and retained receipts.
• The rendering surface: custom adapters and cancellation.
• Performance: caches and bounded native decoding.