Advantages in Using Colour Calibration for Orthophoto Reconstruction

Area of Science:

• Agricultural Science
• Remote Sensing
• Photogrammetry

Background:

• Unmanned Aerial Vehicles (UAVs) are increasingly vital sensor platforms in precision agriculture.
• Photogrammetry using UAVs is crucial for crop and environmental monitoring.
• Atmospheric conditions can significantly impact the accuracy of photogrammetric data.

Purpose of the Study:

• To evaluate the impact of color calibration on photogrammetric performance in precision agriculture.
• To assess how different weather conditions affect color-calibrated and uncalibrated UAV imagery.
• To determine if color calibration can rectify atmospheric distortions in agricultural field monitoring.

Main Methods:

• Conducted light drone flights over an experimental agricultural field for three consecutive days.
• Performed thirty random photogrammetric reconstructions across six different field areas.
• Compared color-calibrated orthophotos against uncalibrated ones to analyze differences in color representation and quantitative parameters.

Main Results:

• Color-calibrated orthophotos exhibited greener and brighter appearances, more accurately reflecting the scene's true colors.
• Calibrated reconstructions consistently showed lower parameter reporting errors.
• Significant differences were noted in camera station percentages and reprojection errors between calibrated and uncalibrated data.

Conclusions:

• Color calibration algorithms can effectively rectify atmospheric conditions, leading to improved orthophoto quality.
• The proposed color calibration protocol enhances the reliability of UAV-based photogrammetric data for agricultural monitoring.
• This protocol is potentially valuable for integration into robotic platforms for diverse environmental exploration and monitoring tasks.