remotion-to-hyperframes

---
name: remotion-to-hyperframes
description: Translate an existing Remotion (React-based) video composition into a HyperFrames HTML composition. Use ONLY when the user explicitly asks to port, convert, migrate, translate, or rewrite a Remotion composition as HyperFrames — for example "port my Remotion project to HyperFrames", "convert this Remotion code to HyperFrames", "migrate from Remotion", "translate this Remotion comp", or "rewrite this as HyperFrames HTML". Do NOT use when (a) the user is authoring a NEW HyperFrames composition, even if they have or are A/B-testing a similar Remotion video; (b) the user mentions Remotion in passing without asking for migration; (c) the user shares Remotion code as reference material rather than asking for a translation; (d) the user asks for "the same video as my Remotion one" without explicitly asking to migrate the source — treat that as a fresh HyperFrames build. When in doubt, default to authoring a native HyperFrames composition with the `hyperframes` skill instead. Skill detects unsupported patterns (useState, useEffect with side effects, async calculateMetadata, third-party React component libraries, `@remotion/lambda` features) and recommends the runtime interop escape hatch instead of attempting a lossy translation.
---

# Remotion to HyperFrames

## Overview

Translate Remotion (React-based) video compositions into HyperFrames (HTML + GSAP) compositions. Most Remotion idioms have direct HyperFrames equivalents — the translation is mechanical for ~80% of typical compositions. This skill encodes the mapping and guards against the lossy 20% by refusing to translate patterns that don't fit HF's seek-driven model and recommending the runtime interop pattern from [PR #214](https://github.com/heygen-com/hyperframes/pull/214) instead.

The skill ships with a **tiered test corpus** (T1–T4, 4 fixtures total) that grades translations against measured SSIM thresholds. Don't translate without running the eval — a translation that "looks right" but renders 0.05 SSIM lower than the validated baseline is silently wrong.

## Workflow

### Step 1: Lint the source

Run [`scripts/lint_source.py`](scripts/lint_source.py) over the Remotion source directory. The lint detects patterns that can't translate cleanly:

- **Blockers** (refuse + recommend interop): `useState`, `useReducer`, `useEffect`/`useLayoutEffect` with non-empty deps, async `calculateMetadata`, third-party React UI libraries (MUI, Chakra, Mantine, antd, shadcn, Radix, NextUI).
- **Warnings** (translate after dropping the construct): `@remotion/lambda` config, `delayRender`, `useCallback`, `useMemo`, custom hooks.
- **Info** (translate with note): `staticFile`, `interpolateColors`.

If any blocker fires, **stop**. Read [`references/escape-hatch.md`](references/escape-hatch.md) and surface the recommendation message. Warnings don't stop translation — drop the offending construct in step 3 and note the gap in `TRANSLATION_NOTES.md`. `@remotion/lambda` config is the canonical warning case: the skill drops the import + `renderMediaOnLambda(...)` calls but translates the rest of the composition.

### Step 2: Plan the translation

Read [`references/api-map.md`](references/api-map.md) — the index of every Remotion API and its HF equivalent or per-topic reference. Identify which topic references you'll need based on what the source uses:

| Source contains                                                           | Load reference                                |
| ------------------------------------------------------------------------- | --------------------------------------------- |
| `Composition`, `defaultProps`, `schema`, `calculateMetadata`              | [`parameters.md`](references/parameters.md)   |
| `Sequence`, `Series`, `Loop`, `AbsoluteFill`, `Freeze`                    | [`sequencing.md`](references/sequencing.md)   |
| `useCurrentFrame`, `interpolate`, `spring`, `Easing`, `interpolateColors` | [`timing.md`](references/timing.md)           |
| `Audio`, `Video`, `Img`, `IFrame`, `staticFile`, `delayRender`            | [`media.md`](references/media.md)             |
| `TransitionSeries`, `@remotion/transitions`                               | [`transitions.md`](references/transitions.md) |
| `@remotion/lottie`                                                        | [`lottie.md`](references/lottie.md)           |
| `@remotion/google-fonts/<Family>`, `Font.loadFont`, `@font-face`          | [`fonts.md`](references/fonts.md)             |

Don't load all of them — load only what the specific source needs.

### Step 3: Generate the HF composition

Emit `index.html` with:

- Root `<div id="stage">` carrying the composition's `data-composition-id`, `data-start="0"`, `data-duration` (in seconds), `data-fps`, `data-width`, `data-height`, plus one `data-*` per scalar prop.
- A flat list of scene divs with `data-start` / `data-duration` / `data-track-index`.
- Inline `<style>` for layout; CSS sets the `from` state of every animated property.
- A single `<script>` tag at the bottom containing one paused `gsap.timeline({paused: true})`. Every Remotion `useCurrentFrame()` derivation becomes a tween on this timeline at the right offset.
- `window.__timelines["<composition-id>"] = tl;` registers the timeline with HF's runtime.

Custom React subcomponents inline as repeated HTML using the prop interface as the template (see [`parameters.md`](references/parameters.md) for the per-instance `data-*` pattern).

### Step 4: Validate

Run the eval harness — [`references/eval.md`](references/eval.md) for the full guide. Quick path:

```bash
# Render Remotion baseline (after npm install in the fixture)
cd remotion-src && npx remotion render <CompositionId> out/baseline.mp4

# Render HF translation
cd ../hf-src && npx hyperframes render --output ../hf.mp4

# SSIM diff
../../scripts/render_diff.sh ./remotion-src/out/baseline.mp4 ./hf.mp4 ./diff
```

Threshold: ~0.02 below `p05` of the source's complexity tier (see `eval.md`'s validated thresholds table). If the diff fails, run [`scripts/frame_strip.sh`](scripts/frame_strip.sh) to see _which_ frames diverged, then re-read the relevant timing/sequencing/media reference.

**Critical**: both renders must use matching pixel format. Set `Config.setVideoImageFormat("png")` + `Config.setColorSpace("bt709")` in the Remotion source's `remotion.config.ts` — otherwise the diff measures encoder differences (~0.05 SSIM hit), not translation fidelity.

### Step 5: Document gaps

Anything that didn't translate cleanly (volume ramps dropped, custom presentations approximated, fonts substituted) gets a `TRANSLATION_NOTES.md` written next to the HF output. See [`references/limitations.md`](references/limitations.md) for the format.

## What this skill explicitly does NOT do

- **Translate React state machines.** Compositions that drive animation via `useState` + `useEffect` are not deterministic frame-capture targets in HyperFrames' seek-driven model. Recommend the runtime interop pattern.
- **Run Remotion's render pipeline alongside HyperFrames.** That's the runtime interop pattern from [PR #214](https://github.com/heygen-com/hyperframes/pull/214) — a separate solution for compositions that fail this skill's lint.

(`@remotion/lambda` is _not_ a blocker — Lambda config is deployment, not animation. The skill drops it as a warning and translates the rest. See [`references/escape-hatch.md`](references/escape-hatch.md).)

## How to grade your own translation

Run the test corpus orchestrator:

```bash
./assets/test-corpus/run.sh
```

It runs T1, T2, T3 (render + diff) and T4 (lint validation), prints a per-tier pass/fail table, and emits an aggregate JSON report. Use this to verify the skill is working end-to-end on a clean checkout — and as a regression check after editing any reference.

Validated baseline (as of 2026-04-27):

| Tier | Composition shape                           | Mean SSIM | Threshold |
| ---- | ------------------------------------------- | --------- | --------- |
| T1   | single-element fade-in                      | 0.974     | 0.95      |
| T2   | multi-scene + spring + audio + image        | 0.985     | 0.95      |
| T3   | data-driven, custom subcomponents, count-up | 0.953     | 0.90      |
| T4   | escape-hatch (8 lint cases)                 | 8/8 pass  | n/a       |