Files
miga-heygen aee81b76a6 docs(engine): ship the fast-capture-limitations.md every gate points at
drawElementService.ts, frameCapture.ts, compileStage.ts,
fallbackCaptureProfile.ts, validate-fast-video.ts, and the fast-video CI
workflow all cite `docs/fast-capture-limitations.md` (several by specific
`Lim N` number) as the reference for why a composition falls back to
screenshot capture -- but the file never existed anywhere in the repo, so
every one of those pointers was dangling and nothing was ever shipped in
the published @hyperframes/engine package either.

Add packages/engine/docs/fast-capture-limitations.md covering every
fallback gate (SwiftShader, video capture, unsupported CSS effects, 3D
contexts, supersampling, clip-cut boundaries, the at-risk-timeline
predictor) plus the operational requirements and per-frame recoverable
errors, and add "docs" to the package's `files` so it actually publishes.

Add a regression test asserting the doc exists and still defines every
limitation number cited by name elsewhere in the codebase.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
2026-09-11 17:58:07 +00:00
..
2026-03-21 22:43:56 -07:00

@hyperframes/engine

Seekable web-page-to-video rendering engine built on Puppeteer and FFmpeg.

Framework-agnostic: works with GSAP, Lottie, Three.js, CSS animations, or any web content that implements the window.__hf seek protocol.

Install

npm install @hyperframes/engine

Requirements: Node.js >= 22, Chrome/Chromium (auto-downloaded by Puppeteer), FFmpeg

What it does

The engine opens your HTML composition in a headless Chrome instance, seeks frame-by-frame using Chrome's HeadlessExperimental.beginFrame API, captures screenshots, and encodes them into video with FFmpeg.

Key services

Service Description
browserManager Launches and pools headless Chrome instances (chrome-headless-shell)
frameCapture Manages capture sessions — seek, screenshot, buffer lifecycle
screenshotService BeginFrame-based capture with CDP (Chrome DevTools Protocol)
chunkEncoder FFmpeg encoding with chunked concat, GPU detection, faststart
streamingEncoder Pipe frames to FFmpeg in real time (no intermediate PNGs on disk)
audioMixer Parse <audio> elements and mix audio tracks via FFmpeg
videoFrameExtractor Extract frames from <video> elements for compositing
parallelCoordinator Split frame ranges across worker processes
fileServer Serve local HTML files to the browser via Hono

Usage

import {
  acquireBrowser,
  createCaptureSession,
  initializeSession,
  captureFrame,
  closeCaptureSession,
} from "@hyperframes/engine";

// 1. Launch browser
const browserLease = await acquireBrowser({ captureMode: "beginFrame" });

// 2. Open a capture session
const session = createCaptureSession({
  browser: browserLease.browser,
  url: "http://localhost:3000/my-composition.html",
  width: 1920,
  height: 1080,
  fps: 30,
});
await initializeSession(session);

// 3. Capture frames
for (let i = 0; i < totalFrames; i++) {
  await captureFrame(session, i, `/tmp/frames/frame-${i}.png`);
}

// 4. Clean up
await closeCaptureSession(session);
await browserLease.release();

Most users should use @hyperframes/producer or the hyperframes CLI instead of calling the engine directly.

Documentation

Full documentation: hyperframes.heygen.com/packages/engine