Files
hyperframes/packages/engine
Miguel Ángel 84edce908a fix: address code review feedback on process cleanup
- Blocker: arm 3s force-exit timer BEFORE awaiting cleanup, not
  inside .finally(). Prevents hang if drainBrowserPool() blocks on
  dead Chrome.
- Reorder cleanup: killTrackedProcesses() (sync, fast) runs first,
  then async browser drain. Ffmpeg dies immediately instead of
  surviving if the hard timer fires early.
- SIGKILL escalation: processTracker now SIGTERMs all tracked
  processes, then SIGKILLs survivors after 500ms grace period.
- Scope pgrep to current user (pgrep -u $(id -u)) so orphan
  detection doesn't touch other users' Chrome on shared machines.
- Add process.on('exit') handler for crash paths (unhandled
  exceptions/rejections that bypass signal handlers).
- Document Windows no-op behavior on killProcessTree handlers.
2026-05-22 23:53:46 -04:00
..
2026-05-22 13:37:28 -04:00

@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,
  releaseBrowser,
  createCaptureSession,
  initializeSession,
  captureFrame,
  closeCaptureSession,
} from "@hyperframes/engine";

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

// 2. Open a capture session
const session = createCaptureSession({
  browser: browser.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 releaseBrowser(browser);

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

Documentation

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