Files
Vance Ingalls 9b51615648 fix(engine): abort sibling VST bounces when a track's chain hard-fails
processCompositionAudio's per-element loop races each track's async chain
concurrently via Promise.all, which rejects as soon as the first element
fails without waiting for siblings still in flight. A VstChainProcessingError
from one track therefore let another track's VST sidecar subprocess (up to
BOUNCE_TIMEOUT_MS = 10 minutes) keep running after the finally block deleted
workDir out from under it.

Thread an internal AbortController's signal through every element's chain
(extract/prepare/applyVstChainToWav), aborting it in a catch around
Promise.all before workDir is removed, and abort it on the caller's own
external signal too. applyVstChainToWav now accepts { signal } and kills its
spawned sidecar on abort, following runFfmpeg's existing spawn-abort
convention.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
2026-07-16 18:49:18 -07:00
..
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