## What Two small render-side improvements for video-heavy compositions: 1. **`packages/core/src/runtime/media.ts`** — gate the per-tick `el.currentTime = relTime` set + the `el.load()` drift-recovery retry on the *absence* of a `<img id="__render_frame_<id>__">` sibling (i.e., we're in render mode + this video's visual is bypassed by frame injection + its audio is mixed by ffmpeg from source files). 2. **`packages/engine/src/services/videoFrameInjector.ts`** — probe `window.__hfReseekGpu` and `window.__hf.colorGrading.redraw` once at the first injector call; cache the booleans; skip the per-frame `page.evaluate` round-trips when neither capability is registered. ## Why #### media.ts During render the runtime calls `el.currentTime = relTime` on every active video per sync tick. For frame-injected videos that's pure waste: - The visual comes from the `<img id="__render_frame_<id>__">` sibling injected by the producer's `videoFrameInjector` — the `<video>` element is `visibility: hidden`. - Audio is mixed by ffmpeg from the source files in `runAudioStage` (separate stage) — it never goes through the in-browser audio pipeline during render. So every per-tick seek just kicks Chrome's media pipeline (buffering checks, range fetches, decoder state changes) for no visible or audible benefit. On a 30 × 32 MB synth comp, that's ~2,400 wasted seeks per render — and the cost wasn't on the JS critical path, so it didn't show up in `avgBeforeCapture` directly. It bled into the BeginFrame compositor's per-frame screenshot time. Preview is unaffected: the injection sibling only exists during render. In preview `hasInjectionSibling` is always false → existing seek path runs unchanged. #### videoFrameInjector.ts The injector hook ran `__hfReseekGpu` and `redrawRuntimeColorGrading` via `page.evaluate` on every render frame. For comps that don't register either capability (the common case — anything without WebGL/WebGPU video sub-comps or a color-grading layer), each was a no-op page-side function preceded by a ~CDP-round-trip-worth of overhead. Probing once and caching `false` eliminates that for the rest of the render. ## How was this validated Stress shape: `synth-30-heavy` — 30 × 32 MB MP4 / 3 s each, sequenced end-to-end over a 90 s timeline (`data-composition-id` root + per-video `<video id="vid-NN" data-start data-duration data-track-index>`). Host: 8-core / 30 GB Linux. N=3 baseline against stock `origin/main` (post-#1630), N=3 with-fix on the same machine, same corpus, fresh worker pool each run. Phase timings via `[Render:trace]` JSON; per-frame sub-breakdown via a one-line `[CapturePerf]` stderr emit (kept locally, not in this PR — `dedupPerfs` already carries the data, this branch surfaces it). | | Baseline N=3 | With-fix N=3 | Δ | |---|---|---|---| | wall mean | 119.5 s ± 1.4 s | **117.3 s ± 0.9 s** | **-2.2 s (-1.8%)** | | avg screenshot / frame | 50.0 ms | **49.0 ms** | -2.0% | | avg beforeCapture / frame | 13.0 ms | **12.1 ms** | -7.0% | | avg total / frame | 66.0 ms | 63.9 ms | -3.2% | | output md5 | `5a22be64...` | identical ×3 | ✓ | The 1 ms screenshot drop is the load-bearing signal: it confirms the kicked Chrome media-pipeline work *was* bleeding into BeginFrame compositor time, even though it wasn't on the JS critical path. Per-frame budget improved 2.1 ms × 2700 / 3 workers ≈ 1.9 s of `capture_disk` savings, which matches the observed wall delta. This stacks cleanly with #1630 (which removed the injector's fileServer contention). #1630 moved the injector's PNG fetches off the fileServer's hot path; this PR keeps Chrome's media pipeline quiet during render so the BeginFrame compositor runs unhindered. ## Test plan - [x] Local-CLI render on `synth-30-heavy` × N=3 baseline + N=3 with-fix; wall, per-frame, md5 captured (above). - [x] Lint / format / typecheck via lefthook pre-commit (`oxlint`, `oxfmt`, `fallow audit`, `tsc --noEmit` across `@hyperframes/core` + `@hyperframes/engine` + `@hyperframes/producer`). - [ ] *Real-world video-heavy comp validation* — would love a Magi / Miga eye on a HF-heygen-stripe-shape or a Rahino-shape comp to confirm there's no audible artifact on unmuted videos. The change shouldn't affect them — in render mode the audio path is ffmpeg, not the in-browser pipeline — but a sanity-check render is cheap. ## Scope notes - *Not addressed in this PR*: the user-facing request for an upfront-extract concurrency cap (`Promise.all` in `extractAllVideoFrames` is currently unbounded across all videos). Filing as a follow-up PR — different layer of the pipeline, different user surface (CLI flag), worth keeping separate for review. - *Edge case*: in the calibration test-frame phase, the injection sibling may not yet exist when drift recovery first checks a video at the very start of its active window. The gate correctly defaults to "no sibling → run the seek" in that case, which is the existing behavior. _Authored by Jerrai (Rames team)._
Write HTML. Render video. Built for agents.
Quickstart | Showcase | Playground | Catalog | Docs | Discord
HyperFrames is an open-source framework for turning HTML, CSS, media, and seekable animations into deterministic MP4 videos. Use it locally with the CLI, from AI coding agents with skills, or as the rendering core behind hosted authoring workflows.
Quick Start
With an AI coding agent
Install the HyperFrames skills, then describe the video you want:
npx skills add heygen-com/hyperframes
Try a prompt like:
Using
/hyperframes, create a 10-second product intro with a fade-in title, a background video, and subtle background music.
The skills teach agents the HyperFrames production loop: plan the video, write valid HTML, wire seekable animations, add media, lint, preview, and render. They work with Claude Code, Cursor, Gemini CLI, Codex, and other coding agents that support skills.
For visual design handoff workflows, see the Claude Design guide and Open Design guide.
Manually with the CLI
npx hyperframes init my-video
cd my-video
npx hyperframes preview # preview in browser with live reload
npx hyperframes render # render to MP4
Requirements: Node.js 22+, FFmpeg
What You Can Build
Need ideas? Browse the Showcase for finished videos you can watch, read, run, and remix.
- Product launch videos and feature announcements
- PR walkthroughs with animated code diffs, narration, and captions
- Data visualizations, chart races, and map animations
- Social videos with kinetic captions, overlays, and music
- Docs-to-video, PDF-to-video, and website-to-video explainers
- Reusable motion graphics for automated content pipelines
Frame.md
frame.md — your design system, ready for video.
Every brand has a design.md. None of them were written for a camera. frame.md is the missing translation layer: it takes your web-context design spec and inverts it for the frame — the same tokens, the same rules, but rewritten so an AI agent can compose a promo video without guessing at scale or reaching for web chrome.
The output is a DESIGN.md superset your whole toolchain can read. Atoms stay sacred. Composition stays free. Numbers come from the script.
Biennale Yellow |
BlockFrame |
Blue Professional |
Bold Poster |
Broadside |
Capsule |
Cartesian |
Cobalt Grid |
Coral |
Creative Mode |
Browse and remix them all at hyperframes.dev/design.
How It Works
Define a video as HTML. Add data attributes for timing and tracks. Use GSAP, CSS, Lottie, Three.js, Anime.js, WAAPI, or your own frame adapter for seekable animation.
<div id="stage" data-composition-id="launch" data-start="0" data-width="1920" data-height="1080">
<video
class="clip"
data-start="0"
data-duration="6"
data-track-index="0"
src="intro.mp4"
muted
playsinline
></video>
<h1 id="title" class="clip" data-start="1" data-duration="4" data-track-index="1">Launch day</h1>
<audio
data-start="0"
data-duration="6"
data-track-index="2"
data-volume="0.5"
src="music.wav"
></audio>
<script src="https://cdn.jsdelivr.net/npm/gsap@3/dist/gsap.min.js"></script>
<script>
const tl = gsap.timeline({ paused: true });
tl.from("#title", { opacity: 0, y: 40, duration: 0.8 }, 1);
window.__timelines = window.__timelines || {};
window.__timelines.launch = tl;
</script>
</div>
Preview instantly in the browser. Render locally or in Docker. The renderer seeks each frame in headless Chrome and encodes the result with FFmpeg, so the same input produces the same video.
HyperFrames Stack
HyperFrames is the open-source rendering engine, plus a growing set of tools around HTML-native video creation.
| Piece | Status | What it does |
|---|---|---|
| CLI | Available | Scaffold, preview, lint, inspect, and render local video projects |
| Core / Engine / Producer | Available | Parse compositions, drive headless Chrome, encode video, and mix audio |
| Catalog | Available | Reusable blocks and components for transitions, overlays, captions, charts, maps, and effects |
| Agent skills | Available | Teach coding agents the video-production patterns that generic web docs miss |
| Studio | Available, evolving | Browser surface for previewing and editing compositions |
| AWS Lambda rendering | Available | Deploy a distributed render stack and drive renders from your laptop or CI |
| hyperframes.dev | Available | Community playground for previewing, iterating, sharing, and rendering HTML-native video projects |
| frame.md | Available | Invert your design system for the camera — a DESIGN.md superset an agent can compose video from |
Catalog
Install ready-to-use blocks and components:
npx hyperframes add flash-through-white # shader transition
npx hyperframes add instagram-follow # social overlay
npx hyperframes add data-chart # animated chart
Browse the catalog at hyperframes.heygen.com/catalog.
Why HyperFrames?
- HTML-native: compositions are HTML files with data attributes. No React requirement, no proprietary timeline format.
- Agent-friendly: agents already write HTML, and the CLI is non-interactive by default.
- Deterministic: same input, same frames, same output. Built for CI, regression tests, and automated rendering.
- No build step: an
index.htmlcomposition plays as-is and can be previewed directly in the browser. - Adapter-based animation: bring GSAP, CSS animations, Lottie, Three.js, Anime.js, WAAPI, or a custom runtime.
- Open source: Apache 2.0 license, with no per-render fees or commercial-use thresholds.
HyperFrames vs Remotion
HyperFrames is inspired by Remotion. Both tools render video with headless Chrome and FFmpeg. The main difference is the authoring model: Remotion's bet is React components; HyperFrames' bet is plain HTML that humans and agents can both write easily.
| HyperFrames | Remotion | |
|---|---|---|
| Authoring | HTML + CSS + seekable animation | React components |
| Build step | None; index.html plays as-is |
Bundler required |
| Agent handoff | Plain HTML files | JSX / React project |
| Library-clock animations | Seekable, frame-accurate via adapters | Wall-clock animation patterns need care |
| Distributed rendering | Local and AWS Lambda render paths | Remotion Lambda, mature cloud renderer |
| License | Apache 2.0 | Source-available Remotion License |
Read the full comparison in the HyperFrames vs Remotion guide.
Documentation
Full documentation: hyperframes.heygen.com/introduction
Packages
| Package | Description |
|---|---|
hyperframes |
CLI for creating, previewing, linting, and rendering compositions |
@hyperframes/core |
Types, parsers, generators, linter, runtime, and frame adapters |
@hyperframes/engine |
Seekable page-to-video capture engine using Puppeteer and FFmpeg |
@hyperframes/producer |
Full rendering pipeline for capture, encode, and audio mix |
@hyperframes/studio |
Browser-based composition editor UI |
@hyperframes/player |
Embeddable <hyperframes-player> web component |
@hyperframes/shader-transitions |
WebGL shader transitions for compositions |
@hyperframes/aws-lambda |
AWS Lambda SDK and deployment surface for distributed renders |
Community
HyperFrames is used in production at HeyGen, with community examples from teams like tldraw, TanStack, and others in ADOPTERS.md. Open a PR if your team is using HyperFrames.
- Questions and ideas: Discord
- Bugs and feature requests: GitHub Issues
- Security reports: SECURITY.md
- Contributions: CONTRIBUTING.md
Development Note
The repo uses Git LFS for golden regression-test baselines under packages/producer/tests/**/output.mp4 (about 240 MB of .mp4 files). If you're cloning the full repo for development, install Git LFS first:
# macOS
brew install git-lfs
# Ubuntu / Debian
sudo apt install git-lfs
# Windows
winget install GitHub.GitLFS
# Then, once per machine
git lfs install
If you only need source files, you can skip LFS content:
GIT_LFS_SKIP_SMUDGE=1 git clone https://github.com/heygen-com/hyperframes.git










