Files
Miguel Ángel 8e1ea7adc2 feat(studio): marquee selection, AE presets, per-keyframe ease + velocity fitting
Marquee selection: click+drag on empty canvas draws a dashed selection
rectangle. All elements whose OBB intersects are group-selected via
SAT. Shift+marquee adds to selection. Click on empty deselects.

Per-keyframe easing: each keyframe segment has its own ease, editable
via expandable bezier curve editor in the Animation panel. Parser
preserves per-keyframe ease through round-trips (ease-only updates
preserve existing properties).

AE Easy Ease presets: correct After Effects bezier values (0.333, 0,
0.667, 1) in the preset grid.

Velocity-based curve fitting: gesture recordings analyze velocity
profile and assign per-keyframe custom eases automatically.

Gesture smoothing: Gaussian-weighted moving average (from PR #1658)
+ easeEach support for keyframed tweens + fetch-cancellation race
fix in useGsapAnimationsForElement.
2026-06-24 00:42:14 -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