mirror of
https://github.com/heygen-com/hyperframes.git
synced 2026-09-03 04:38:33 +00:00
Vance IngallsandClaude Sonnet 5
8052f3e68f
Renders what B3 already routes in preview: a group's members sub-mix into
one PCM WAV at full composition length (adelay already places each member
at its composition position, so the group WAV's t=0 IS composition time),
run through the group's own FX chain and automation via the same
applyAudioFxChain/envelope-bake path a member uses, then fold into the flat
track list as one processed AudioTrack — the final mixAudioTracks call
never has to know groups exist.
Gain law verified against plans/spikes/amix-nesting-spike.sh (brought over
from the plans branch, along with audioMixer.grouping.test.ts, since both
were committed there and never merged to origin/main — every step branch in
this stack descends from origin/main): the sub-mix's own amix prefers
normalize=0 (nulls exactly against a flat mix), falling back to per-node
compensation by the group's OWN member count only when this ffmpeg build's
amix rejects the option. Carrying any other count into a nested amix node
is the exact +2.499 dB silent failure the spike measured — confirmed by a
manual mutation check (wrong-count compensation landed 3.5 dB hot, exactly
20*log10(3/2) for a 2-member group compensated as 3; reverted after
confirming the level test catches it).
A group element carrying data-hidden drops every member before the sub-mix
ever runs (RULES: mute-by-drop, never mute-by-volume-0) — parseAudioElements
now resolves groups once per parse and skips hidden-group members the same
way it already skips data-hidden ancestors.
HfAudioGroup (packages/core/src/audioGroups.ts, from B1) gains fxChain,
automation, volume and hidden, read off the group element the same way
resolveAudioGroups already reads data-label — audioGroups.test.ts updated
for the wider shape plus new coverage for the added reads.
it.todo("mixes a grouped composition at the same level as the ungrouped
one") is now a real, passing test; two more added per the step doc (FX
routing isolation, member-level envelope survives grouping).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
@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
Related packages
@hyperframes/core— types, parsers, frame adapters@hyperframes/producer— high-level render pipeline built on this enginehyperframes— CLI