Files
James df80182452 fix(engine): add bt709 color space + range conversion to H.264/H.265 encoding
Chrome captures frames in full-range sRGB, which maps to BT.709. Without
explicit color metadata, players guess the wrong color space and range,
causing color shifts and crushed dark values across devices.

Changes:
- Embed bt709 color info in H.264/H.265 VUI via x264-params/x265-params
  (colorprim, transfer, colormatrix) and FFmpeg metadata flags
- Add scale filter (in_range=pc:out_range=tv) to convert full-range
  Chrome screenshots to limited/TV range expected by H.264 decoders
- Chain range conversion with VAAPI's existing hwupload filter
- Add -video_track_timescale 90000 for consistent A/V timing
- Skip color metadata and range conversion for VP9/ProRes
- 8 new regression tests for color space, range filter, VAAPI chain,
  GPU skip, VP9 skip, and timescale

Verified via ffprobe: color_space=bt709, color_transfer=bt709,
color_primaries=bt709, color_range=tv, time_base=1/90000.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-04-07 16:58:28 +00:00
..
2026-04-03 04:36:19 +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,
  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