Axiom Cut

A complete, code-directed video editing Agent. Import real footage, describe the result in natural language, keep every operation editable on a timeline, and render a real downloadable MP4 with FFmpeg.

What v1.0 includes

• Persistent local media library with FFprobe metadata
• Multi-video timeline with trim, split, duplicate, move, speed, volume, and deletion
• 16:9, 9:16, 1:1, 4:3, and 4:5 output
• Live brightness, contrast, saturation, temperature, and vignette preview
• Editable title and timed subtitle tracks
• FFmpeg shot-change, silence, and suggested-cut analysis
• DeepSeek structured planning from a natural-language brief
• Project-scoped self-evolution: critique, three mutations, selection, memory, and rollback
• Undo/redo, autosave, project JSON import/export, and version snapshots
• Real queued FFmpeg rendering with progress, cancellation, and MP4 download
• H.264 video, AAC audio, Chinese title/subtitle burn-in, and multi-clip concatenation
• Built-in NEON SYNC media pack with nine full-duration 720p source proxies and one Agent result
• A separate presentation mode with two 100% React/SVG code films and one licensed real-footage before/after film

Run locally

Requirements:

• Node.js 20 or newer
• FFmpeg and FFprobe available on PATH

On macOS, FFmpeg can be installed with brew install ffmpeg.

npm install
cp .env.example .env
npm run dev

Open http://127.0.0.1:4173.

How to use it

1. Click 导入真实视频 and choose one or more video files.
2. Click 分析当前素材 to detect shots, silence, and possible cut points.
3. In Agent, describe the target, such as “做成 9:16 高密度口播，前两秒先给结论，去掉停顿并加入字幕”.
4. Click 执行剪辑. The plan and every active step remain visible while executable changes are written to the timeline.
5. Fine-tune clips in 调整: trim, speed, volume, aspect, color, title, and captions.
6. Use the timeline toolbar to split, duplicate, move, or delete a selected clip. Undo and redo are always available.
7. Open 导出, click 开始真实渲染, wait for 100%, and download the MP4.
8. Use 版本 or project JSON export whenever a reversible checkpoint is needed.

The media store lives in the operating system's temporary Axiom Cut directory and is recovered after a server restart. Project structure is autosaved in the browser. A downloaded project JSON contains references and editing data, not the media bytes or API key.

DeepSeek setup

Put the key in the server-side .env file:

DEEPSEEK_API_KEY=your_key
DEEPSEEK_MODEL=deepseek-v4-flash

The browser calls /api/plan and /api/evolve; the key is never sent to the client bundle. When the key is absent or the provider is unavailable, the editor keeps working with a deterministic local planning fallback. Media pixels are never sent to DeepSeek; only the written brief and non-visual technical metadata are used for planning.

Real rendering pipeline

Persistent source videos + editable project timeline
        ↓
FFprobe metadata + FFmpeg shot/silence analysis
        ↓
DeepSeek plan + deterministic, reversible project actions
        ↓
FFmpeg scale/crop → trim → speed → grade → audio → concat
        ↓
ASS title/subtitle burn-in → H.264/AAC MP4 → download

Run the real renderer smoke test with:

npm run test:render

The test creates two temporary videos, uploads and analyzes them, renders an intentionally out-of-order timeline with real black/silent gaps, applies color and ASS overlays, verifies title placement and subtitle fallback at pixel level, then confirms H.264/AAC with FFprobe. Temporary test artifacts are removed afterward.

Demo mode

Click 展示 Demo to open the presentation-oriented films:

• Derivative / local linearity — an 18-second, four-chapter mathematical story with a code-drawn car, exact Bézier curve, secant, tangent, shrinking delta, and limit formula.
• Flux Note product launch — a 12-second product film with staged typography, device UI, feature cards, and CTA motion.
• Neon Sync performance cut — a synchronized 14-second before/after comparison built from real dance footage: a continuous wide take on the left and a seven-shot, dual-angle, color-graded, titled, beat-driven Agent edit on the right. Use the draggable split to compare both versions at the same output timecode.

The first two demos are built from React/SVG frame logic. Neon Sync uses licensed Pexels footage and a fully reproducible FFmpeg build; no generated image is used.

The editor's built-in NEON SYNC library contains nine full-duration, silent 1280×720 source proxies from one verified shoot, plus the 14-second Agent result:

• Neon indoor set · 4: 13648582, 13648584, 13648585, and 13648588
• Rooftop set · 5: 13648581, 13648583, 13648586, 13648587, and 13648589

These assets appear in the media library but are never added to the timeline automatically; select one and use 加入时间线 when needed. Rebuild missing assets with:

npm run demo:neon

Force regeneration of every proxy, poster, and comparison output with:

AXIOM_DEMO_FORCE=1 npm run demo:neon

All nine source clips are by khanhhoangminh on Pexels and are used under the Pexels License. Attribution is included even though it is not required. The depicted dancers and creator do not endorse, sponsor, or represent Axiom Cut. See public/demo/neon-sync/CREDITS.md for the exact asset record.

API overview

• GET /api/status
• GET /api/media
• POST /api/media
• GET /api/media/:id
• GET /api/media/:id/file
• POST /api/media/:id/analyze
• DELETE /api/media/:id
• POST /api/plan
• POST /api/evolve
• GET /api/render
• POST /api/render
• GET /api/render/:id
• DELETE /api/render/:id
• GET /api/render/:id/download

Boundaries

• The subtitle track is fully editable and rendered into the MP4. v1.0 does not bundle a speech-to-text model; Agent-created caption text is a draft, not a claimed transcription.
• The included queue is deliberately local and single-worker. A hosted multi-user deployment should move media and jobs to isolated persistent workers.
• The server accepts videos up to 500 MB and renders up to 12 clips / 60 minutes per job.

Open-source notes

• License: MIT
• Bundled Neon Sync footage remains subject to the Pexels license described in its credits file; the application source code remains MIT.
• See THIRD_PARTY_NOTICES.md for the repository-level media notice.
• No 3Blue1Brown artwork, logo, or source material is included. The mathematical demo uses an original code-native visual system.
• Never commit .env or API keys.

Tech stack

React 19, TypeScript, Vite, Express, HTML5 Video, SVG/CSS, DeepSeek API, FFmpeg, FFprobe, and ASS/libass.