ArUco Online Scanner

A fast, lightweight web application for detecting and decoding ArUco markers directly in your browser.

Features

• Multi-Dictionary Detection: Automatically tests against all predefined ArUco dictionaries (4x4, 5x5, 6x6, 7x7, AprilTag, and Original).
• Robust Image Processing: Automatically attempts to decode markers in four different image variations:
  • Standard RGB
  • Inverted RGB (useful for dark-themed or inverted markers)
  • Grayscale
  • Inverted Grayscale
• Privacy-First: All image processing is done locally in your browser using OpenCV.js. No images are uploaded to any server.
• Drag & Drop: Simple interface for uploading images by dragging them onto the workspace.

How to Use

1. Open the Scanner: Open index.html in any modern web browser.
2. Upload an Image: Drag and drop an image file (PNG, JPEG, WebP) onto the upload zone, or click the zone to select a file from your device.
3. Wait for Analysis: The application uses your device's CPU to run the OpenCV.js detection engine. It may take a moment to scan through all 22+ dictionaries and 4 image variations.
4. View Results:
   • Detected markers will be highlighted on the image canvas with colorful bounding boxes and ID labels.
   • A detection report will list each unique Marker ID found, the dictionary used, and the image variation that successfully decoded it.

Technical Details

• Built with: HTML5, CSS3 (Vanilla), and JavaScript.
• Computer Vision: Powered by OpenCV.js.
• AESTHETICS: Features a dark-mode glassmorphism theme for a clean, modern look.

Local Testing

Since this tool uses standard web APIs, you can run it by opening index.html directly from your file system. Note that some advanced browser security policies (CORS) may occasionally interfere with cv.imread() on local files; if this occurs, the script will attempt to decode the error and notify you in the browser console.