Using Action Cameras to Collect Tree Measurements

Theodore Hartsook, Sarah Bisbing, Alireza Tavakkoli, Jonathan Greenberg

Abstract: This study investigated the use of a consumer-grade action camera to generate a 3D recreation of a newly established forest plot using structure from motion (SfM) techniques. We tested a novel approach that used 2 videos collected with a GoPro HERO 9 Black during plot setup. After the plot center and witness trees were identified, we recorded the approach and a short walkthrough of the plot that included the witness trees and the plot center stake. Image frames along with position and orientation metadata were extracted from each video. These images were processed in the Pix4DMapper photogrammetry software and exported as 3D point clouds. These point clouds were processed using PDAL to remove noise, identify ground points, and calculate height above ground. Tree position, DBH, and height were extracted from the point cloud and compared to field measurements to assess the utility and practicality of the terrestrial SfM point cloud.