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Updated: May 2, 2026
Video Movement Analysis Using Smartphones ViMAS: A Pilot Study
Published on: March 14, 2017
Single Shot High-Accuracy Diameter at Breast Height Measurement with Smartphone Embedded Sensors
Wang Xiang1, Songlin Fei2, Song Zhang1
1School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA.
None:
Tree diameter at breast height (DBH) is a fundamental metric in forest inventory and management. This paper presents a novel method for DBH estimation using the built-in light detection and ranging (LiDAR) and red, green and blue (RGB) sensors of an iPhone 13 Pro, aiming to improve measurement accuracy and field usability. A single snapshot of a tree, capturing both depth and RGB images, is used to reconstruct a 3D point cloud. The trunk orientation is estimated based on the point cloud to locate the breast height, enabling robust DBH estimation independent of the capture angle. The DBH is initially estimated by the geometrical relationship between trunk size on the image and the depth of the trunk. Finally, a pre-computed lookup table (LUT) is employed to improve the initial DBH estimates into accurate values. Experimental evaluation on 294 trees within a capture range of 0.25 m to 5 m demonstrates a mean absolute error of 0.53 cm and a root mean square error of 0.63 cm.
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