Scale Resolution
Analytics also help with distance and area calculation from aerial drone images from disparate points of time and real-world GPS coordinates.
The following prompts and responses explain these:
Case 1:
Prompt:
Given the attached aerial drone image and its Estimated Coordinates: Latitude = 42.3736, Longitude = -71.1097 and its scale resolution as 2cm in image=50feet in actual distance, find the square footage occupied by the building with a circular structure.
Response:
The square footage occupied by the building with the circular structure in the attached aerial image is approximately 81,300 square feet.frame5.jpg
Calculation Method
• The circular structure was located and its size was estimated using the image's pixel dimensions and known scale: 2 cm in image = 50 feet actual.frame5.jpg
• The circle's diameter was estimated visually based on the image dimensions, and this scale was used to convert pixel measurements into real-world feet.
• The area was then calculated using the formula for the area of a circle: πr2\pi r^2πr2, with the radius converted to feet.frame5.jpg
Assumptions
• The building's central circular feature fully encompasses the occupied area (overestimating the whole structure if non-circular parts extend the actual footprint).
• Image DPI was assumed to be 96 if metadata was missing, which is standard for web images.frame5.jpg
• Manual visual estimation introduces possible error, but provides a close real-world approximation given the described scale and visible features.
• frame5.jpg
Case 2:
Prompt:
Given the bounding box locations of the nearest (Latitude 42.37043, Longitude: -71.12165) and the farthest (Latitude: 42.37125, Longitude: -71.11733) points on the rectangular area covered by the drone in its tour and a scale resolution of 2cm on image = 50 feet on ground, what was the total area in square miles surveyed by the drone.
Response:
Ground area covered: 0.012494 square miles
This can be confirmed with:
from math import radians, cos, sin, asin, sqrt
# Step 1: Haversine function to compute distances in meters
def haversine(lat1, lon1, lat2, lon2):
R = 6371000 # Earth's radius in meters
dlat = radians(lat2 - lat1)
dlon = radians(lon2 - lon1)
a = sin(dlat/2)**2 + cos(radians(lat1))*cos(radians(lat2))*sin(dlon/2)**2
c = 2 * asin(sqrt(a))
return R * c
# Bounding rectangle corners (nearest and farthest)
lat_min, lon_min = 42.37043, -71.12165
lat_max, lon_max = 42.37125, -71.11733
# Compute east-west (width) and north-south (height) ground distances, in meters
height_m = haversine(lat_min, lon_min, lat_max, lon_min)
width_m = haversine(lat_min, lon_min, lat_min, lon_max)
# Step 2: Area in square meters
area_m2 = width_m * height_m
# Step 3: Convert to square feet (1 m = 3.28084 ft)
area_ft2 = area_m2 * (3.28084 ** 2)
# Step 4: Convert to square miles (1 sq mile = 27,878,400 sq ft)
area_miles2 = area_ft2 / 27878400
print(f"Ground area covered: {area_miles2:.6f} square miles")
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