no code implementations • 31 Dec 2016 • Hamid Hamraz, Marco A. Contreras, Jun Zhang
This paper presents a tree segmentation approach for multi-story stands that stratifies the point cloud to canopy layers and segments individual tree crowns within each layer using a digital surface model based tree segmentation method.
no code implementations • 1 Jan 2017 • Hamid Hamraz, Marco A. Contreras, Jun Zhang
This paper presents a non-parametric approach for segmenting trees from airborne LiDAR data in deciduous forests.
no code implementations • 17 Feb 2017 • Hamid Hamraz, Marco A. Contreras, Jun Zhang
Existing segmentation procedures typically detect more than 90% of overstory trees, yet they barely detect 60% of understory trees because of the occlusion effect of higher canopy layers.
no code implementations • 17 Jul 2017 • Hamid Hamraz, Marco A. Contreras
In this chapter, we present (i) a robust segmentation method that avoids a priori assumptions about the canopy structure, (ii) a vertical canopy stratification procedure that improves segmentation of understory trees, (iii) an occlusion model for estimating the point density of each canopy stratum, and (iv) a distributed computing approach for efficient processing at the forest level.
no code implementations • 24 Feb 2018 • Hamid Hamraz, Nathan B. Jacobs, Marco A. Contreras, Chase H. Clark
Lastly, the classification accuracies of overstory trees (~90%) were more balanced than those of understory trees (~90% deciduous and ~65% coniferous), which is likely due to the incomplete capture of understory tree crowns via airborne LiDAR.