Files
Vance Ingalls 4b476697ef feat(engine): gate backdrop-filter / filter:blur|drop-shadow / webgl from fast capture
drawElementImage cannot faithfully reproduce these, producing 18-49 dB damaged
frames (community eval). Add detectCssEffectRisk: scans computed styles under
the composition root for backdrop-filter (samples the compositor backdrop the
single-element capture has no access to) and filter:blur/drop-shadow (paint-record
vs compositor inconsistency), plus the accel-canvas registry for any WebGL
context (custom GLSL shaders animated via GSAP with no rAF freeze under
seek-based capture; the drawImage composite can't un-freeze them). Any match
routes the comp to the platform screenshot baseline, same contract as the
video / stacked-fade / 3D gates. HF_FAST_CAPTURE_CSSFX=true bypasses for R&D.

Verified on the 6 damaged community comps: 5 (backdrop-filter x2, filter:blur x2,
webgl x1) now fall back to screenshot (PSNR -> inf); the 6th is a deterministic
44 dB residual with no signature (imperceptible, left on the fast path).

Note: the webgl gate over-gates static/redraw-on-seek WebGL that the composite
handles cleanly; a per-frame canvas-redraw probe could re-admit those later.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-14 22:57:53 -07:00
..
2026-06-13 02:04:21 -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