Towards accurate individual tree parameters estimation in dense forest: optimized coarse-to-fine algorithms for registering UAV and terrestrial LiDAR data

Since TLS data is too big to upload, the dataset can only contain the example ULS point cloud data in different forest types (i.e., coniferous, mixed broadleaf-coniferous, broadleaf) before coarse-to-fine registration. The fused TLS and ULS data after registration can be used for the estimation of individual tree parameters (i.e., DBH and tree height) . B-1ULS and B-3ULS represent the ULS data of plot 1 and 3 in broadleaf forests, respectively; C-2ULS and C-4ULS represent the ULS data of plot 2 and 4 in coniferous forests, respectively; M-1ULS and M-2ULS represent the ULS data of plot 1 and 2 in mixed broadleaf-coniferous forests, respectively.