Miguel Ángel 1614dd3e5a fix(cli): sample real pixels behind hidden text for contrast-audit
## What

Fixes five reported false-positive/false-negative patterns in the WCAG contrast audit (`hyperframes validate --contrast`):

1. **SVG fill vs. text color** — foreground read from CSS `color` instead of SVG `fill`.
2. **Cross-component color bleed** — background estimate bleeds into a neighboring panel/layer.
3. **Backdrop-filter glass text** — background estimate misses the blur/tint and reads the raw backdrop.
4. **Partially-overlapping translucent decoration** — a decorative shape inside or partly touching the text's bbox goes undetected.
5. **Solid-fill pill/button** — investigated, did **not** reproduce; already handled correctly by the existing own-background ancestor walk. Not touched.

## Why

The audit estimated an element's background two ways:
- foreground: always `getComputedStyle(el).color` — wrong for SVG `<text>`/`<tspan>`, which is painted via `fill`, an independent CSS property.
- background: a 4px pixel ring sampled just **outside** the text's bounding box, with a fallback to an ancestor's opaque `background-color` for solid pills/buttons.

The ring is a proximity heuristic. It's wrong whenever what's immediately outside the text differs from what's actually behind it:
- text near the edge of its own panel, with a differently-colored sibling panel/layer just past the bbox — the ring samples the neighbor.
- a `backdrop-filter: blur()` glass panel sized only a couple pixels larger than the text — the ring exits the panel into the raw, unblurred, untinted backdrop.
- a translucent decoration that only partially overlaps the ring, or sits entirely **inside** the bbox — invisible to the ring regardless of size.

## How

**SVG fill (#1):** elements inside an `<svg>` (`el.ownerSVGElement`) now prefer the computed `fill` when it resolves to a solid `rgb()`/`rgba()` color, falling back to `color` for paint values that aren't a plain color (`none`, `context-fill`, gradient/pattern refs).

**Cross-comp bleed / glass blur / partial decoration (#2–#4):** replaced the ring-sampling + own-background-ancestor-walk heuristic with a two-phase capture:
1. `__contrastAuditPrepare()` walks the DOM, computes each candidate's foreground (unchanged logic from #1), and **hides that element's own text paint** (`color`/`fill` → `transparent`, layout-neutral — no reflow).
2. The caller takes **one** screenshot with the glyphs invisible (same number of screenshots as before — just moved after the hide instead of before it).
3. `__contrastAuditFinish(imgBase64, time, candidates)` restores the original paint immediately, then samples the **real composited pixels directly inside each element's own bbox** — no proximity heuristic needed, since these are the exact pixels that were behind the glyphs.

This is a real architectural change to `contrast-audit.browser.js`'s calling contract (single `__contrastAudit` → `__contrastAuditPrepare`/`__contrastAuditFinish`), with `validate.ts`'s `runContrastAudit` updated to match, including a try/finally restore-safety-net so a mid-loop screenshot/decode failure can't leave a later sample auditing a page with stale hidden text.

Mirrored the identical change in `skills/hyperframes-creative/scripts/contrast-report.mjs`, which duplicates the same DOM-walk/sampling logic (not just the WCAG math). There, the **visible** frame for the human-facing overlay image still comes from the producer's normal `captureFrameToBuffer` path (unchanged); only the **background-sampling** capture is a plain `session.page.screenshot()` taken after hiding text — deliberately bypassing `captureFrameToBuffer`, whose static-frame dedup cache knows nothing about the DOM mutation and would hand back a stale pre-mutation buffer.

**Solid-fill pill (#5):** reproduced a rounded pill/button with a busy page background outside it. The existing own-background ancestor walk already resolves the pill's declared `background-color` correctly regardless of the rounded corners — confirmed via repro, both before and after this change report the identical (correct) result. No fix needed; left untouched, and this case is covered by the new architecture too (would give the same right answer even without the ancestor-walk fallback).

Added `packages/cli/src/commands/contrast-sample.ts` (mirroring the existing `contrast-bg.ts`/`contrast-fg.ts` pattern) hosting the pure sample-rect/grid-point computation, unit tested — the browser-injected scripts can't import it directly, so it's kept in sync by hand, same convention as the rest of this file.

## Test plan

- [x] Unit tests: `contrast-fg.test.ts` (SVG fill resolution), `contrast-sample.test.ts` (sample-rect clamping/degenerate cases), plus the full `packages/cli` suite (1424 tests) passes, including an updated `layout-audit.browser.test.ts` case that called the old single-function `__contrastAudit` API directly.
- [x] Manual verification — standalone `puppeteer-core` harness against real `chrome-headless-shell`, one minimal HTML fixture per pattern, comparing the audit's reported ratio/verdict against a hand-constructed ground truth:
  - **SVG fill**: `fill:white` / no `color` on black bg → before: `fg=rgb(0,0,0)` ratio `1:1` (false FAIL); after: `fg=rgb(255,255,255)` ratio `21:1` (correct PASS).
  - **Cross-comp bleed**: text on a black sibling highlight box 2px larger than the text, white page bg outside it → before: `bg=rgb(255,255,255)` ratio `1.23:1` (false FAIL); after: `bg=rgb(0,0,0)` ratio `17.14:1` (correct PASS).
  - **Glass blur**: black text on an 18%-white-tinted `backdrop-filter: blur(14px)` panel over a yellow/blue gradient, panel only ~2px larger than the text → before: `bg=rgb(0,64,255)` (raw gradient color, blur/tint completely missed) ratio `3.18:1` (false FAIL); after: `bg=rgb(159,160,165)` (correct blurred/tinted blend) ratio `8.05:1` (correct PASS).
  - **Partial decoration**: text 92%-covered by a translucent white badge on a dark bg → before: `bg=rgb(16,16,16)` (ring never touches the badge, which sits entirely inside the bbox) ratio `17.45:1` (false PASS); after: `bg=rgb(171,171,171)` (correctly detects the badge) ratio `2.11:1` (correct FAIL).
  - **Solid pill sanity**: unaffected — `bg=rgb(10,10,10)` ratio `19.8:1` before and after.
- [x] End-to-end: ran the actual `hyperframes validate --contrast` CLI command (via `tsx src/cli.ts`) against a real scaffolded project containing all 4 patterns simultaneously — only the genuinely-failing case (the 92%-covered decoration) is reported (`1.09:1`, need `3:1`); the cross-comp-bleed, glass-blur, and solid-pill cases are correctly silent. A second vanilla scaffold with plain white-on-dark text produces zero false positives.
- [x] `oxlint`, `oxfmt --check`, and `tsc --noEmit` all pass on the changed files.
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HyperFrames

npm version npm downloads License Node.js Discord

Write HTML. Render video. Built for agents.

Quickstart | Showcase | Playground | Catalog | Docs | Discord

HyperFrames demo: HTML code on the left transforms into a rendered video on the right

HyperFrames is an open-source framework for turning HTML, CSS, media, and seekable animations into deterministic MP4 videos. Use it locally with the CLI, from AI coding agents with skills, or as the rendering core behind hosted authoring workflows.

Quick Start

With an AI coding agent

Install the HyperFrames skills, then describe the video you want:

npx skills add heygen-com/hyperframes --full-depth --yes

--full-depth does a full clone of the repo's current main. Without it, skills add fetches the skills.sh registry blob, which lags main by hours — you'd get an older copy of a skill. (hyperframes skills update already installs full-depth.)

Try a prompt like:

Using /hyperframes, create a 10-second product intro with a fade-in title, a background video, and subtle background music.

The skills teach agents the HyperFrames production loop: plan the video, write valid HTML, wire seekable animations, add media, lint, preview, and render. They work with Claude Code, Cursor, Gemini CLI, Codex, and other coding agents that support skills.

Skills

HyperFrames ships 20 skills agents load on demand. Read /hyperframes first — it's the router and capability map; it picks a workflow for any "make me a…" request — video, deck, or composition port — and points to the domain skills below.

Run npx skills add heygen-com/hyperframes --full-depth for the interactive picker, npx skills add heygen-com/hyperframes --all --full-depth to install all 20 at once (skips the picker), or npx skills add heygen-com/hyperframes --skill <name> --full-depth for just one (bare name, no leading /). Keep --full-depth — it installs the current main; without it skills add fetches the skills.sh blob, which lags by hours.

Installs stay lean after that: npx hyperframes init keeps the core set fresh (the router, the hyperframes-* domain skills, and media-use — plus whatever is already installed; /figma stays on demand) and never expands a partial install; the creation workflows install on demand — the router runs npx hyperframes skills update <workflow> before entering one. Nothing re-pulls the full set behind your back.

Router

Skill Use when
/hyperframes Read first for any request to make / create / edit / animate / render a video, animation, or motion graphic. Capability map for the domain skills and intent router for the creation workflows below.

Creation workflows

Skill Use when
/product-launch-video Marketing / launching / promoting a product — from its URL, a brief, or a script (even if the site is only named). Up to ~3 min (sweet spot 30-90s).
/website-to-video Turning a general website into a video — site tour, portfolio / landing-page showcase, social clip from the site's own visuals.
/faceless-explainer Explaining a topic / concept from arbitrary text — no product, no URL, no website capture; every visual is LLM-invented (typography / abstract / diagram / data-viz).
/pr-to-video A GitHub pull request (PR URL, owner/repo#N ref, or "this PR") → changelog / feature-reveal / fix / refactor explainer, read via the gh CLI.
/embedded-captions Adding captions / subtitles to an existing talking-head video (footage untouched) — verbatim rail, embedded climax behind the subject, or pure-cinematic embed.
/talking-head-recut Packaging an existing talking-head / interview / podcast video with designed graphic overlays — lower-thirds, data callouts, kinetic titles, pull-quotes, side panels, PiP.
/motion-graphics A short, unnarrated, design-led motion graphic (~under 10s) — kinetic type, stat / chart hit, logo sting, lower-third, animated tweet / headline. MP4 or transparent overlay.
/music-to-video A music track (audio file, or video to pull audio from) → a beat-synced video — lyric, slideshow, or kinetic promo; music drives pacing.
/slideshow A presentation / pitch deck / interactive deck — discrete slides, fragment reveals, branching, hotspot navigation, presenter mode. Output is a navigable deck, not a rendered video.
/general-video Anything else — longer or multi-scene pieces, brand / sizzle reel, title card, static loop, freeform composition. Input- and length-agnostic fallback.
/remotion-to-hyperframes Porting an existing Remotion (React) composition's source to HyperFrames HTML. One-way migration, not creation.

Domain skills (loaded on demand)

Atomic capabilities the creation workflows compose against — pull one when you need that specific layer.

Skill Covers
/hyperframes-core The composition contract — data-* timing attributes, class="clip", tracks, sub-compositions, variables, framework-owned media playback, determinism rules.
/hyperframes-animation All animation knowledge — atomic motion rules, scene blueprints, transitions, runtime adapters (GSAP / Lottie / Three.js / Anime.js / CSS / WAAPI / TypeGPU).
/hyperframes-keyframes Seek-safe keyframe authoring across runtimes — GSAP timelines, CSS keyframes, Anime.js, WAAPI, FLIP, paths, masks, SVG morph/draw, 3D depth — plus hyperframes keyframes diagnostics for rendered motion.
/hyperframes-creative Non-animation creative direction — frame.md / design.md, palettes, typography, narration, beat planning, audio-reactive visuals, composition patterns.
/media-use The media OS — resolve any media need (BGM, SFX, image, icon, logo, voice, color grade, LUT) into a frozen local file or paste-ready block + ledger record, generate via TTS/music/image models when the catalog misses, transcribe, caption, remove backgrounds, and reuse assets across projects. One shared audio engine + manifest tracking.
/hyperframes-cli CLI dev loop — init, lint, validate, inspect, preview, render, publish, doctor, plus AWS Lambda cloud rendering (lambda deploy / render / progress).
/hyperframes-registry Install and wire registry blocks and components into compositions via hyperframes add. Authoring a new block or component to contribute upstream.
/figma Import Figma assets, tokens, components, and storyboard sections → reconstructed motion (frames read as states, not slides) (REST/CLI) plus Motion animations (MCP) and shaders (MCP source / native export) into a composition.

For visual design handoff workflows, see the Claude Design guide and Open Design guide.

Manually with the CLI

npx hyperframes init my-video
cd my-video
npx hyperframes preview      # preview in browser with live reload
npx hyperframes render       # render to MP4

Requirements: Node.js 22+, FFmpeg

What You Can Build

Need ideas? Browse the Showcase for finished videos you can watch, read, run, and remix.

  • Product launch videos and feature announcements
  • PR walkthroughs with animated code diffs, narration, and captions
  • Data visualizations, chart races, and map animations
  • Social videos with kinetic captions, overlays, and music
  • Docs-to-video, PDF-to-video, and website-to-video explainers
  • Reusable motion graphics for automated content pipelines

Frame.md

frame.md — your design system, ready for video.

Every brand has a design.md. None of them were written for a camera. frame.md is the missing translation layer: it takes your web-context design spec and inverts it for the frame — the same tokens, the same rules, but rewritten so an AI agent can compose a promo video without guessing at scale or reaching for web chrome.

The output is a DESIGN.md superset your whole toolchain can read. Atoms stay sacred. Composition stays free. Numbers come from the script.

Biennale Yellow
Biennale Yellow
BlockFrame
BlockFrame
Blue Professional
Blue Professional
Bold Poster
Bold Poster
Broadside
Broadside
Capsule
Capsule
Cartesian
Cartesian
Cobalt Grid
Cobalt Grid
Coral
Coral
Creative Mode
Creative Mode

Browse and remix them all at hyperframes.dev/design.

How It Works

Define a video as HTML. Add data attributes for timing and tracks. Use GSAP, CSS, Lottie, Three.js, Anime.js, WAAPI, or your own frame adapter for seekable animation.

<div id="stage" data-composition-id="launch" data-start="0" data-width="1920" data-height="1080">
  <video
    class="clip"
    data-start="0"
    data-duration="6"
    data-track-index="0"
    src="intro.mp4"
    muted
    playsinline
  ></video>

  <h1 id="title" class="clip" data-start="1" data-duration="4" data-track-index="1">Launch day</h1>

  <audio
    data-start="0"
    data-duration="6"
    data-track-index="2"
    data-volume="0.5"
    src="music.wav"
  ></audio>

  <script src="https://cdn.jsdelivr.net/npm/gsap@3/dist/gsap.min.js"></script>
  <script>
    const tl = gsap.timeline({ paused: true });
    tl.from("#title", { opacity: 0, y: 40, duration: 0.8 }, 1);
    window.__timelines = window.__timelines || {};
    window.__timelines.launch = tl;
  </script>
</div>

Preview instantly in the browser. Render locally or in Docker. The renderer seeks each frame in headless Chrome and encodes the result with FFmpeg, so the same input produces the same video.

HyperFrames Stack

HyperFrames is the open-source rendering engine, plus a growing set of tools around HTML-native video creation.

Piece Status What it does
CLI Available Scaffold, preview, lint, inspect, and render local video projects
Core / Engine / Producer Available Parse compositions, drive headless Chrome, encode video, and mix audio
Catalog Available Reusable blocks and components for transitions, overlays, captions, charts, maps, and effects
Agent skills Available Teach coding agents the video-production patterns that generic web docs miss
Studio Available, evolving Browser surface for previewing and editing compositions
AWS Lambda rendering Available Deploy a distributed render stack and drive renders from your laptop or CI
hyperframes.dev Available Community playground for previewing, iterating, sharing, and rendering HTML-native video projects
frame.md Available Invert your design system for the camera — a DESIGN.md superset an agent can compose video from

Catalog

Install ready-to-use blocks and components:

npx hyperframes add flash-through-white   # shader transition
npx hyperframes add instagram-follow      # social overlay
npx hyperframes add data-chart            # animated chart

Browse the catalog at hyperframes.heygen.com/catalog.

Why HyperFrames?

  • HTML-native: compositions are HTML files with data attributes. No React requirement, no proprietary timeline format.
  • Agent-friendly: agents already write HTML, and the CLI is non-interactive by default.
  • Deterministic: same input, same frames, same output. Built for CI, regression tests, and automated rendering.
  • No build step: an index.html composition plays as-is and can be previewed directly in the browser.
  • Adapter-based animation: bring GSAP, CSS animations, Lottie, Three.js, Anime.js, WAAPI, or a custom runtime.
  • Open source: Apache 2.0 license, with no per-render fees or commercial-use thresholds.

HyperFrames vs Remotion

HyperFrames is inspired by Remotion. Both tools render video with headless Chrome and FFmpeg. The main difference is the authoring model: Remotion's bet is React components; HyperFrames' bet is plain HTML that humans and agents can both write easily.

HyperFrames Remotion
Authoring HTML + CSS + seekable animation React components
Build step None; index.html plays as-is Bundler required
Agent handoff Plain HTML files JSX / React project
Library-clock animations Seekable, frame-accurate via adapters Wall-clock animation patterns need care
Distributed rendering Local and AWS Lambda render paths Remotion Lambda, mature cloud renderer
License Apache 2.0 Source-available Remotion License

Read the full comparison in the HyperFrames vs Remotion guide.

Documentation

Full documentation: hyperframes.heygen.com/introduction

Packages

Package Description
hyperframes CLI for creating, previewing, linting, and rendering compositions
@hyperframes/core Types, parsers, generators, linter, runtime, and frame adapters
@hyperframes/engine Seekable page-to-video capture engine using Puppeteer and FFmpeg
@hyperframes/producer Full rendering pipeline for capture, encode, and audio mix
@hyperframes/studio Browser-based composition editor UI
@hyperframes/player Embeddable <hyperframes-player> web component
@hyperframes/shader-transitions WebGL shader transitions for compositions
@hyperframes/aws-lambda AWS Lambda SDK and deployment surface for distributed renders

Community

HyperFrames is used in production at HeyGen, with community examples from teams like tldraw, TanStack, and others in ADOPTERS.md. Open a PR if your team is using HyperFrames.

Development Note

The repo uses Git LFS for golden regression-test baselines under packages/producer/tests/**/output.mp4 (about 240 MB of .mp4 files). If you're cloning the full repo for development, install Git LFS first:

# macOS
brew install git-lfs

# Ubuntu / Debian
sudo apt install git-lfs

# Windows
winget install GitHub.GitLFS

# Then, once per machine
git lfs install

If you only need source files, you can skip LFS content:

GIT_LFS_SKIP_SMUDGE=1 git clone https://github.com/heygen-com/hyperframes.git

License

Apache 2.0

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Write HTML. Render video. Built for agents.
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