mirror of
https://github.com/heygen-com/hyperframes.git
synced 2026-09-01 19:42:03 +00:00
## Summary Fix four interrelated bugs in the opacity pipeline. The headline fix: the HDR compositor was effectively ignoring direct-on-`<video>` opacity animation because the engine itself was clobbering inline opacity with `opacity: 0 !important` — switching to `visibility: hidden` resolves the bug at the root. ## Why `Chunk 1` of `plans/hdr-followups.md`. This was the most user-visible bug in the entire follow-ups list: a GSAP-controlled opacity tween directly on a `<video>` element under HDR rendered at full brightness instead of fading. ## What changed **1A — Stop clobbering native `<video>` opacity.** `screenshotService.injectVideoFramesBatch` and `syncVideoFrameVisibility` were applying `opacity: 0 !important` to native `<video>` elements to hide them under the injected `<img>`. That stomp clobbered any GSAP-controlled inline opacity, so the next seek read 0 from computed style and the comp went black. Switched to `visibility: hidden !important` only. Visibility hides the element from rendering without changing its opacity, so subsequent reads (and `queryElementStacking`) see the real GSAP value on every frame. The `parseFloat(...) || 1` recovery hack at `injectVideoFramesBatch` was specifically there to compensate for this stomp; it's now replaced with a `Number.isNaN` guard that defaults to 1 only when parsing actually fails. **1B — `Number.isNaN` guards in `queryVideoElementBounds`.** `parseFloat(style.opacity) || 1` silently coerced a real opacity of 0 into 1. Switched to explicit `Number.isNaN` checks so opacity 0 stays 0. Same fix for `parseFloat(style.zIndex)`. **1C — `instanceof HTMLElement` instead of cast.** `resolveRadius` cast `el as HTMLElement` to read `offsetWidth`/`Height`. SVG and other non-HTML elements would have crashed at runtime. Replaced the cast with an `instanceof HTMLElement` guard, and made the numeric fallback `Number.isNaN`-safe. **1D — Opacity walk starts from the element itself.** The walk in `queryVideoElementBounds` started from `el.parentElement` for HDR videos to skip past the engine's forced `opacity: 0` on the element itself. Now that the engine never sets opacity, the special case is unnecessary — always walk from `el`. Kept the `isHdrEl` lookup because transform/border-radius logic further down still branches on it. ## Test plan - [x] `bun run --filter @hyperframes/engine typecheck` clean. - [x] `bun run --filter @hyperframes/engine test` — 308/308 passing. - [x] `bun run --filter @hyperframes/producer typecheck` clean. - [x] `oxlint` + `oxfmt --check` on both touched files. - [x] `hdr-regression` Window C (the direct-opacity window) now passes against the regenerated golden — see follow-up PR in this stack which tightens the budget. ## Stack Chunk 1 of `plans/hdr-followups.md`. Window C of the regression suite documents the bug; the next PR in the stack regenerates the golden and tightens its `maxFrameFailures` budget.
@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
Related packages
@hyperframes/core— types, parsers, frame adapters@hyperframes/producer— high-level render pipeline built on this enginehyperframes— CLI