Minicut — Web Video Editor

A simple web-based video editor with timeline editing, overlay support, and FFmpeg-powered export.

Features

• Upload video/audio files (MP4, MOV, WebM, MKV) via drag-and-drop or file picker
• Timeline editing with 4 tracks (1 main + 3 overlay layers)
• Trim, split, and reorder clips on the main track
• Multi-layer overlay with position, size, and opacity controls
• Canvas preview with real-time compositing
• Export to MP4 (H.264 + AAC) via FFmpeg
• Range request support for streaming large files

Tech Stack

• Backend: Node.js (built-in http module, no frameworks)
• Frontend: Vanilla HTML/CSS/JS + HTML5 Canvas
• Media processing: FFmpeg / ffprobe via child_process
• Storage: Local filesystem (no database)

Project Structure

project/
├── server.js              # All backend logic
├── public/
│   ├── index.html          # Main page
│   ├── style.css           # Styles
│   └── editor.js           # Editor logic
├── uploads/                # Uploaded source files
├── output/                 # Exported files + job status
├── SPEC.md                 # Project specification
└── AGENTS.md               # AI execution protocol

Getting Started

Prerequisites

• Node.js 18+
• FFmpeg and ffprobe installed and available in PATH

Installation

# No dependencies to install — uses only Node.js built-in modules

Running

node server.js

Open http://localhost:3000 in a browser.

Set a custom port:

PORT=8080 node server.js

Usage

1. Upload media — Click "Add media" or drag files into the upload area
2. Edit timeline — Drag clips to reorder, resize to trim, use Split to divide clips
3. Add overlays — Drag media onto overlay tracks (1-3), adjust position and opacity
4. Preview — Use the canvas preview and transport controls
5. Export — Click "Export" to render the final video

API Reference

Upload

Method	Path	Description
POST	/api/upload	Upload a video/audio file (multipart/form-data)
GET	/api/media/:id	Get media info
GET	/api/media/:id/stream	Stream media file (supports Range)

Export

Method	Path	Description
POST	/api/export	Start export job with timeline JSON
GET	/api/export/:jobId/status	Get export job status and progress
GET	/api/export/:jobId/download	Download exported file (supports Range)

Export Settings

• Container: MP4
• Video: mpeg4
• Audio: AAC, 128kbps
• Default resolution: 1280x720 @ 30fps

License

GNU General Public License v3 (GPLv3) — see LICENSE file