detect tree stems and estimate DBH using TreeLS package

treels_stem_dbh() is an all-in-one function to process height normalized .las|.laz files using the functionality of the TreeLS package. The function generates a list of stems and estimates DBH directly from the point cloud. treels_stem_dbh() outputs:

A .laz file with the Classification data updated to: ground points (class 2); water points (class 9); stem points (class 4); non-stem (class 5).
A vector data file in gpkg format with the tree identification stem locations, heights, and DBH estimates.

The order of operations is:

Detect tree stems/boles from the height normalized point cloud using TreeLS::treeMap() with the TreeLS::map.hough() algorithm
Merge overlapping tree coordinates using TreeLS::treeMap.merge()
Assign tree IDs to the original points using TreeLS::treePoints() with the TreeLS::trp.crop() algorithm
Flag only the stem points using TreeLS::stemPoints() with the TreeLS::stm.hough() algorithm
Perform DBH estimation using TreeLS::tlsInventory() with the TreeLS::shapeFit() algorithm

Usage

treels_stem_dbh(
  folder,
  outfolder,
  min_height = 2,
  max_dbh = 2,
  chunk_these = FALSE
)

Arguments

folder: string. The path of a folder containing a set of las/laz files. Can also be a vector of file paths.
outfolder: string. The path of a folder to write the tiled vector files to
min_height: numeric. Set the minimum height (m) for individual tree detection
max_dbh: numeric. Set the largest tree diameter (m) expected in the point cloud
chunk_these: logical. Do the las/laz files need to be tiled to work with smaller subsets? See is_chunked_grid in chunk_las_catalog()

Value

Returns an sf data.frame with TreeLS detected trees and DBH estimated directly from the point cloud. Exports files in the outfolder defined by the user in the function call.

References

https://github.com/tiagodc/TreeLS

Examples

 if (FALSE) { # \dontrun{
 o <- "../data"
 i <- "../data/normlasdata"
 r <- cloud2trees::treels_stem_dbh(folder = i, outfolder = o)
 r %>% names()
 } # }