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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