- inference.ts: force `.toColourspace("b-w")` on the resized mask. Sharp upcasts
the 1-channel raw input to RGB-interleaved during resize, so `fullMask[i]`
was reading R,G,B,R,G,B... of pixels 0..691199 instead of the alpha for all
2,073,600 pixels. Visible symptom: horizontal scanline alpha artifact in
every transparent webm — the avatar appeared semi-transparent throughout.
- pipeline.ts: add BT.709 + limited-range colorspace tags so Chrome's YUV→RGB
matches the source mp4 (without these, ffmpeg's default RGB→YUV is BT.601
and skin tones drift visibly when the cutout is overlaid on its source).
- pipeline.ts: add Quality preset type ("fast"/"balanced"/"best" → CRF 30/18/12).
Default raised from CRF 30 → 18 ("balanced") so the most common pattern
(text-behind-subject) works out of the box without visible doubling.
- remove-background.ts: wire `--quality` flag with validation, +2 examples.
- Tests: BT.709 tags present, quality preset → CRF mapping, default is balanced.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
hyperframes
CLI for creating, previewing, and rendering HTML video compositions.
Install
npm install -g hyperframes
Or use directly with npx:
npx hyperframes <command>
Requirements: Node.js >= 22, FFmpeg
Commands
init
Scaffold a new Hyperframes project from a template:
npx hyperframes init my-video
cd my-video
preview
Start the live preview studio in your browser:
npx hyperframes preview
# Studio running at http://localhost:3002
npx hyperframes preview --port 4567
render
Render a composition to MP4:
npx hyperframes render ./my-composition.html -o output.mp4
lint
Validate your Hyperframes HTML:
npx hyperframes lint ./my-composition
npx hyperframes lint ./my-composition --json # JSON output for CI/tooling
npx hyperframes lint ./my-composition --verbose # Include info-level findings
By default only errors and warnings are shown. Use --verbose to also display informational findings (e.g., external script dependency notices). Use --json for machine-readable output with errorCount, warningCount, infoCount, and a findings array.
compositions
List compositions found in the current project:
npx hyperframes compositions
benchmark
Run rendering benchmarks:
npx hyperframes benchmark ./my-composition.html
doctor
Check your environment for required dependencies (Chrome, FFmpeg, Node.js):
npx hyperframes doctor
browser
Manage the bundled Chrome/Chromium installation:
npx hyperframes browser
info
Print version and environment info:
npx hyperframes info
docs
Open the documentation in your browser:
npx hyperframes docs
upgrade
Check for updates and show upgrade instructions:
npx hyperframes upgrade
npx hyperframes upgrade --check --json # machine-readable for agents
Documentation
Full documentation: hyperframes.heygen.com/packages/cli
Related packages
@hyperframes/core— types, parsers, frame adapters@hyperframes/engine— rendering engine@hyperframes/producer— render pipeline@hyperframes/studio— composition editor UI