🌊 AR Flood Visualizer with Real Measurement

Open-source camera-based flood depth visualization with actual measurement capabilities

See potential flood levels overlaid on your camera feed with REAL measurement accuracy. Uses reference objects (doors, people) to calculate true pixel-per-inch scale for accurate water height visualization.

🚀 Features

• 📏 REAL Measurement System: Uses doors/people as reference for accurate pixel-per-inch scaling
• 📷 Real-time Camera Overlay: Stream your device camera and overlay flood water visualization
• 🎯 Two-Tap Calibration: Tap top & bottom of reference object for instant scale calculation
• 🚪 Multiple References: Standard door (80"), adult male (5'9"), adult female (5'4"), or custom
• 📊 Flexible Configuration: Use risk scores (0-10) or custom depths in meters/feet
• 💾 Screenshot & Share: Capture and share your visualization with measurement data
• 🔒 Privacy-First: All processing happens locally in your browser - no data uploaded
• 📱 Mobile & Desktop: Works on all modern devices with camera access
• ⚡ Zero Dependencies: Pure vanilla JavaScript + Tailwind CSS
• 🎓 No ML Required: Simple math achieves ±5-10% accuracy

🎯 Quick Start

1. Download the files:

   • index.html - Main application
   • ar-flood.js - Core AR logic

2. Serve over HTTPS (camera API requirement):

   # Using Python
   python -m http.server 8000
   
   # Or using Node.js
   npx http-server

3. Open in browser: Navigate to https://localhost:8000

4. Grant camera access when prompted

🎬 How to Use

Setup Your Scenario

1. Enter Configuration:

   • Location/address (optional)
   • Flood risk score (0-10) OR custom depth in m/ft
   • Click "Start AR Camera"

2. Select Reference Object:

   • Standard Door (80" / 6'8") - RECOMMENDED
   • Adult Male (69" / 5'9")
   • Adult Female (64" / 5'4")
   • Custom Height (enter your own)

Calibrate with Two Taps

3. Tap TOP of Reference:

   • Point camera at your reference (e.g., door frame)
   • Tap the TOP of the object (e.g., top of door frame)
   • Green crosshair appears

4. Tap BOTTOM of Reference:

   • Tap the BOTTOM of the same object (e.g., floor level)
   • Red crosshair appears
   • System calculates: pixelsPerInch = pixelDistance / referenceHeight

View Accurate Water Overlay

5. Water Appears:

   • Water drawn at accurate height using your scale
   • Shows measurement in meters and feet
   • "MEASURED" badge confirms calibration
   • Water height: waterY = bottomY - (waterInches × pixelsPerInch)

6. Capture & Share:

   • Tap "Photo" to download screenshot with measurements
   • Tap "Share" to use native share (mobile)

🧮 How It Works

Measurement-Based Approach

Why This Works:

• User selects known-size reference (e.g., standard door = 80 inches)
• Taps top and bottom of reference in camera view
• System calculates pixels-per-inch scale from pixel distance
• Water drawn using real-world measurement, not estimation

Math:

// Step 1: Calculate pixel distance
pixelDistance = Math.sqrt(
  (bottomX - topX)² + (bottomY - topY)²
)

// Step 2: Calculate scale
referenceHeight = 80 inches  // for standard door
pixelsPerInch = pixelDistance / referenceHeight

// Step 3: Draw water at accurate height
waterHeightInches = waterDepthMeters × 39.3701
waterHeightPixels = waterHeightInches × pixelsPerInch
waterY = bottomPoint.y - waterHeightPixels

Accuracy: ±5-10% (good enough for visualization without machine learning)

Why Doors Work Best

• Standardized: Most interior doors are exactly 80" (6'8")
• Vertical: Easy to tap top and bottom
• Common: Found in every home/building
• At Ground Level: On same plane as floor for accurate measurement

Technical Overview

2D Camera Overlay with Measurement:

• Uses getUserMedia() API for camera access
• Canvas draws: camera feed FIRST, then water overlay on top
• Pixel-per-inch scale enables real-world accuracy
• No ML or depth sensors needed

Flood Depth Source:

// Score-based (0-10)
score <= 3: 0.3m / 12"  (ankle-deep)
score 4-6:  0.6m / 24"  (knee-deep)
score 7-8:  1.2m / 48"  (waist-deep)
score 9-10: 1.8m / 72"  (chest-deep)

// Or use custom depth in meters/feet
// Converted to inches for pixel calculation

⚙️ Configuration Options

Reference Object Selection

REFERENCE_OBJECTS = {
    door: 80 inches,    // Standard interior door height
    male: 69 inches,    // Average adult male (5'9")
    female: 64 inches,  // Average adult female (5'4")
    custom: user input  // Your own measurement
}

HTML Inputs

<!-- Reference Selection -->
<select id="reference-select">
  <option value="door">Standard Door (80")</option>
  <option value="male">Adult Male (5'9")</option>
  <option value="female">Adult Female (5'4")</option>
  <option value="custom">Custom Height</option>
</select>

<!-- Custom Height -->
<input id="custom-height-input" type="number" placeholder="Height in inches">

<!-- Flood Configuration -->
<input id="address-input" placeholder="Location">
<input id="score-slider" type="range" min="0" max="10">
<input id="depth-input" type="number" step="0.1">
<select id="depth-unit">
  <option value="meters">meters</option>
  <option value="feet">feet</option>
</select>

JavaScript Config

// Set reference object
referenceObject = 'door';  // 'door' | 'male' | 'female' | 'custom'
customHeight = 60;         // inches, if using 'custom'

// Calibration state
calibrationStep = 'select_ref';  // 'select_ref' | 'tap_top' | 'tap_bottom' | 'complete'
topPoint = { x, y };             // First tap coordinates
bottomPoint = { x, y };          // Second tap coordinates
pixelsPerInch = null;            // Calculated scale

// Water calculation
waterHeightInches = waterDepthMeters * 39.3701;
waterHeightPixels = waterHeightInches * pixelsPerInch;
waterY = bottomPoint.y - waterHeightPixels;

🎨 Customization

Adjust Reference Heights

// In REFERENCE_OBJECTS constant
REFERENCE_OBJECTS = {
    door: { height: 80 },    // Change if non-standard doors
    male: { height: 69 },    // Adjust for regional averages
    female: { height: 64 },
    custom: { height: 60 }   // Default custom value
}

Change Marker Colors

// In drawFrame() function
// TOP marker: Green
ctx.strokeStyle = '#10b981';
ctx.fillStyle = '#10b981';

// BOTTOM marker: Red  
ctx.strokeStyle = '#ef4444';
ctx.fillStyle = '#ef4444';

// Connecting line: Purple
ctx.strokeStyle = '#a855f7';

Adjust Performance

const TARGET_FPS = 30;  // Lower for older devices (e.g., 20)

💡 Best Practices

For Most Accurate Measurements

1. Use Standard Doors: Most reliable reference (80" exactly)
2. Ensure Vertical Reference: Object should be perpendicular to ground
3. Same Plane as Ground: Reference should be at same depth as area you're measuring
4. Steady Camera: Hold device still during tapping
5. Good Lighting: Helps you see reference boundaries clearly
6. Tap Precisely: Tap exact top and bottom edges

Common Use Cases

• Home Evacuation Planning: Visualize water in your rooms
• Educational Demos: Show students real flood depths
• Emergency Preparedness: Train staff on flood scenarios
• Risk Communication: Help clients understand flood impact
• Property Assessment: Show potential damage zones

📱 Browser Compatibility

Browser	Desktop	Mobile	Notes
Chrome	✅	✅	Best performance
Safari	✅	✅	Requires HTTPS
Firefox	✅	✅	Full support
Edge	✅	✅	Chromium-based

Requirements:

• HTTPS connection (or localhost)
• Camera permission granted
• Modern browser (ES6+ support)

⚠️ Important Disclaimers

This is an EDUCATIONAL VISUALIZATION TOOL with measurement capabilities:

• ✅ Provides ±5-10% measurement accuracy using reference objects
• ✅ Great for educational demos and scenario visualization
• ✅ Helps understand flood depths in relatable terms
• ❌ NOT a precise flood prediction model
• ❌ NOT for emergency decision-making
• ❌ NOT a replacement for official FEMA flood maps
• ❌ NOT a survey-grade measurement tool

Measurement Limitations:

• Assumes reference object is at same depth plane as measurement area
• Accuracy depends on camera angle and user tapping precision
• Does not account for camera lens distortion
• Simple 2D calculation, not true 3D spatial measurement

Always consult:

• Official FEMA flood maps for regulatory decisions
• Local emergency management authorities
• Professional surveyors for property assessments
• Licensed engineers for structural planning

🔒 Privacy & Security

• No data collection: Nothing sent to servers
• No tracking: No analytics or cookies
• Local processing: All rendering happens in browser
• No storage: Camera feed not saved (unless you screenshot)
• Open source: Audit the code yourself

📄 License

MIT License - feel free to use, modify, and distribute!

🤝 Contributing

Contributions welcome! Ideas:

• Horizontal reference support (door width for side views)
• Auto-detection of door frames using edge detection
• Multiple calibration points for better accuracy
• 3D depth visualization with perspective correction
• Lens distortion compensation
• Historical flood event presets
• Multi-language support
• Accessibility improvements (voice guidance)

🙏 Credits

Originally developed for RisqMap - a comprehensive climate risk intelligence platform.

Measurement technique inspired by Grok AI's suggestion to use real-world reference objects for pixel-per-inch scale calculation. Open-sourced to help the community visualize flood risk with actual measurement capabilities.

🐛 Troubleshooting

Camera won't open:

• Ensure HTTPS connection (or use localhost)
• Check browser permissions for camera access
• Try different browser (Chrome recommended)
• On iOS: Safari only, Chrome uses Safari engine

Wrong water height:

• Ensure reference object is on same ground plane
• Use standard door for best accuracy (80" exactly)
• Tap precisely at top and bottom edges
• Hold camera steady during calibration
• Ensure good lighting to see boundaries

Calibration markers not showing:

• Check that you've selected a reference object
• Verify camera stream is active
• Try tapping more firmly/precisely
• Refresh page and try again

Water appears in wrong position:

• Complete full two-tap calibration
• Ensure reference is vertical (perpendicular to ground)
• Check that bottomPoint is actually at floor level
• Camera angle should be roughly horizontal

Performance issues:

• Lower TARGET_FPS to 20 (from 30)
• Close other browser tabs
• Use newer device if possible
• Ensure good WiFi/network (though processing is local)
• Check browser permissions (Settings > Privacy > Camera)
• Ensure HTTPS connection
• Try different browser

Water appears wrong height:

• Use calibration feature
• Tap on actual floor/door frame
• Check that camera is level

Performance issues:

• Lower TARGET_FPS in JavaScript
• Close other tabs
• Try on newer device

Screenshot not working:

• Check browser storage permissions
• Try different browser

📧 Support

Having issues? Open an issue on GitHub or contact us.

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