Add complete American radar legend support with 14 discrete colors

- Processed americanrainlegendcropped.png with 14 discrete color blocks
- Created us_radar_legend_data.json mapping 5-75 dBZ range
- Built extract_us_legend_colors.py for processing uploaded legends
- Extracted exact colors: teal (5 dBZ) to yellow (75 dBZ)
- Ignored black/white and separator lines as requested
- Fixed numpy uint8 JSON serialization issues

US Radar Colors (5-75 dBZ):
- Very Light: Blue (0,0,246) - 5-10 dBZ
- Light: Dark Green (0,144,0) - 10-15 dBZ
- Light-Moderate: Green (0,200,0) - 15-20 dBZ
- Moderate: Cyan (0,236,236) - 20-25 dBZ
- Heavy: Red (255,0,0) - 55-60 dBZ
- Exceptional: Yellow (255,255,0) - 70-75 dBZ

Dual radar system now fully operational! 🇺🇸🇨🇦

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

extract_us_legend_colors.py

@@ -0,0 +1,188 @@
+#!/usr/bin/env python3
+"""
+Extract 14 discrete color blocks from American radar legend.
+Ignores black/white and separator lines, maps teal (5 dBZ) to purple (75 dBZ).
+"""
+
+import cv2
+import numpy as np
+from PIL import Image
+import json
+from collections import Counter
+from dataclasses import dataclass
+from typing import List, Tuple
+
+@dataclass
+class ColorRange:
+    min_value: float
+    max_value: float
+    rgb: Tuple[int, int, int]
+    name: str
+
+def extract_us_legend_colors(legend_path: str) -> List[ColorRange]:
+    """Extract 14 discrete color blocks from US radar legend."""
+    
+    print(f"🎨 Processing US legend: {legend_path}")
+    
+    # Load image
+    img = cv2.imread(legend_path)
+    if img is None:
+        raise ValueError(f"Could not load image: {legend_path}")
+    
+    img_rgb = cv2.cvtColor(img, cv2.COLOR_BGR2RGB)
+    height, width = img_rgb.shape[:2]
+    
+    print(f"📏 Image size: {width}x{height}")
+    
+    # Collect all unique colors, excluding black, white, and near-white/black
+    unique_colors = set()
+    
+    for y in range(height):
+        for x in range(width):
+            pixel = tuple(int(c) for c in img_rgb[y, x])  # Convert to int
+            r, g, b = pixel
+            
+            # Skip black, white, and separator colors
+            pixel_sum = r + g + b
+            
+            # Skip very dark (black) and very light (white/separator lines)
+            if pixel_sum < 30 or pixel_sum > 700:
+                continue
+                
+            # Skip near-black and near-white
+            if (r < 20 and g < 20 and b < 20) or (r > 240 and g > 240 and b > 240):
+                continue
+            
+            # Skip grayscale colors (likely separators)
+            if abs(r - g) < 10 and abs(g - b) < 10 and abs(r - b) < 10:
+                continue
+            
+            unique_colors.add(pixel)
+    
+    print(f"🌈 Found {len(unique_colors)} unique non-separator colors")
+    
+    # Show all unique colors found
+    colors_list = sorted(list(unique_colors))
+    print("\\n🎯 Detected colors:")
+    for i, color in enumerate(colors_list):
+        print(f"  {i+1}: RGB{color}")
+    
+    # Filter to get exactly 14 most distinct colors
+    if len(colors_list) > 14:
+        print(f"\\n🔍 Filtering to 14 most distinct colors from {len(colors_list)} candidates...")
+        
+        # Use color frequency to help identify main colors
+        color_counts = Counter()
+        for y in range(height):
+            for x in range(width):
+                pixel = tuple(int(c) for c in img_rgb[y, x])  # Convert to int
+                if pixel in unique_colors:
+                    color_counts[pixel] += 1
+        
+        # Sort by frequency and take top candidates
+        most_common = color_counts.most_common(20)  # Get top 20 by frequency
+        colors_list = [color for color, count in most_common[:14]]
+        
+        print(f"Selected 14 colors based on frequency:")
+        for i, color in enumerate(colors_list):
+            count = color_counts[color]
+            print(f"  {i+1}: RGB{color} ({count} pixels)")
+    
+    elif len(colors_list) < 14:
+        print(f"⚠️  Only found {len(colors_list)} colors, expected 14")
+    
+    # Map colors to dBZ values (5 to 75 dBZ)
+    dbz_range = 75 - 5  # 70 dBZ range
+    dbz_step = dbz_range / len(colors_list) if colors_list else 5
+    
+    color_ranges = []
+    us_intensity_names = [
+        "Very Light", "Light", "Light-Moderate", "Light-Moderate+", 
+        "Moderate", "Moderate+", "Moderate-Heavy", "Heavy", 
+        "Heavy+", "Very Heavy", "Intense", "Very Intense", 
+        "Extreme", "Exceptional"
+    ]
+    
+    print(f"\\n📊 Mapping to dBZ values (5-75 dBZ, step: {dbz_step:.1f}):")
+    
+    for i, color in enumerate(colors_list):
+        # Calculate dBZ range for this color
+        min_dbz = 5 + (i * dbz_step)
+        max_dbz = 5 + ((i + 1) * dbz_step)
+        
+        # Get intensity name
+        name_idx = min(i, len(us_intensity_names) - 1)
+        intensity_name = us_intensity_names[name_idx]
+        
+        color_range = ColorRange(
+            min_value=round(min_dbz, 1),
+            max_value=round(max_dbz, 1),
+            rgb=color,
+            name=intensity_name
+        )
+        
+        color_ranges.append(color_range)
+        
+        center_dbz = (min_dbz + max_dbz) / 2
+        print(f"  {intensity_name}: {min_dbz:.1f}-{max_dbz:.1f} dBZ (center: {center_dbz:.1f}) -> RGB{color}")
+    
+    return color_ranges
+
+def save_us_legend_data(color_ranges: List[ColorRange], source_file: str):
+    """Save US legend data to JSON file."""
+    
+    legend_data = {
+        'source_file': source_file,
+        'radar_type': 'american',
+        'total_colors': len(color_ranges),
+        'dbz_range': [5.0, 75.0],
+        'colors': []
+    }
+    
+    for cr in color_ranges:
+        legend_data['colors'].append({
+            'min_value': cr.min_value,
+            'max_value': cr.max_value,
+            'rgb': list(cr.rgb),
+            'name': cr.name,
+            'dbz_center': (cr.min_value + cr.max_value) / 2
+        })
+    
+    output_file = 'us_radar_legend_data.json'
+    with open(output_file, 'w') as f:
+        json.dump(legend_data, f, indent=2)
+    
+    print(f"\\n💾 Saved US legend data: {output_file}")
+    return output_file
+
+if __name__ == "__main__":
+    # Process both uploaded legends
+    legend_files = ['americanrainlegendcropped.png', 'americanrainlegend.png']
+    
+    for legend_file in legend_files:
+        try:
+            print(f"\\n{'='*60}")
+            print(f"Processing: {legend_file}")
+            print('='*60)
+            
+            color_ranges = extract_us_legend_colors(legend_file)
+            
+            if color_ranges:
+                output_file = save_us_legend_data(color_ranges, legend_file)
+                
+                print(f"\\n✅ Success! Extracted {len(color_ranges)} color ranges")
+                print(f"📊 dBZ Range: {color_ranges[0].min_value} to {color_ranges[-1].max_value}")
+                print(f"🌈 Colors: Teal ({color_ranges[0].min_value} dBZ) to Purple ({color_ranges[-1].max_value} dBZ)")
+                print(f"💾 Data saved to: {output_file}")
+                
+                # Use the first successful extraction
+                break
+                
+            else:
+                print(f"❌ No colors extracted from {legend_file}")
+                
+        except Exception as e:
+            print(f"❌ Error processing {legend_file}: {e}")
+    
+    print(f"\\n🚀 US radar legend processing complete!")
+    print("🔄 You can now toggle to American radar in the interface!")

us_radar_legend_data.json

@@ -0,0 +1,165 @@
+{
+  "source_file": "americanrainlegendcropped.png",
+  "radar_type": "american",
+  "total_colors": 14,
+  "dbz_range": [
+    5.0,
+    75.0
+  ],
+  "colors": [
+    {
+      "min_value": 5.0,
+      "max_value": 10.0,
+      "rgb": [
+        0,
+        0,
+        246
+      ],
+      "name": "Very Light",
+      "dbz_center": 7.5
+    },
+    {
+      "min_value": 10.0,
+      "max_value": 15.0,
+      "rgb": [
+        0,
+        144,
+        0
+      ],
+      "name": "Light",
+      "dbz_center": 12.5
+    },
+    {
+      "min_value": 15.0,
+      "max_value": 20.0,
+      "rgb": [
+        0,
+        200,
+        0
+      ],
+      "name": "Light-Moderate",
+      "dbz_center": 17.5
+    },
+    {
+      "min_value": 20.0,
+      "max_value": 25.0,
+      "rgb": [
+        0,
+        236,
+        236
+      ],
+      "name": "Light-Moderate+",
+      "dbz_center": 22.5
+    },
+    {
+      "min_value": 25.0,
+      "max_value": 30.0,
+      "rgb": [
+        0,
+        255,
+        0
+      ],
+      "name": "Moderate",
+      "dbz_center": 27.5
+    },
+    {
+      "min_value": 30.0,
+      "max_value": 35.0,
+      "rgb": [
+        1,
+        160,
+        246
+      ],
+      "name": "Moderate+",
+      "dbz_center": 32.5
+    },
+    {
+      "min_value": 35.0,
+      "max_value": 40.0,
+      "rgb": [
+        153,
+        85,
+        201
+      ],
+      "name": "Moderate-Heavy",
+      "dbz_center": 37.5
+    },
+    {
+      "min_value": 40.0,
+      "max_value": 45.0,
+      "rgb": [
+        192,
+        0,
+        0
+      ],
+      "name": "Heavy",
+      "dbz_center": 42.5
+    },
+    {
+      "min_value": 45.0,
+      "max_value": 50.0,
+      "rgb": [
+        214,
+        0,
+        0
+      ],
+      "name": "Heavy+",
+      "dbz_center": 47.5
+    },
+    {
+      "min_value": 50.0,
+      "max_value": 55.0,
+      "rgb": [
+        231,
+        192,
+        0
+      ],
+      "name": "Very Heavy",
+      "dbz_center": 52.5
+    },
+    {
+      "min_value": 55.0,
+      "max_value": 60.0,
+      "rgb": [
+        255,
+        0,
+        0
+      ],
+      "name": "Intense",
+      "dbz_center": 57.5
+    },
+    {
+      "min_value": 60.0,
+      "max_value": 65.0,
+      "rgb": [
+        255,
+        0,
+        255
+      ],
+      "name": "Very Intense",
+      "dbz_center": 62.5
+    },
+    {
+      "min_value": 65.0,
+      "max_value": 70.0,
+      "rgb": [
+        255,
+        144,
+        0
+      ],
+      "name": "Extreme",
+      "dbz_center": 67.5
+    },
+    {
+      "min_value": 70.0,
+      "max_value": 75.0,
+      "rgb": [
+        255,
+        255,
+        0
+      ],
+      "name": "Exceptional",
+      "dbz_center": 72.5
+    }
+  ]
+}