treepos_FT: 'ForestTools' tree top detection

In gisma/uavRst: Unmanned Aerial Vehicle Remote Sensing Tools

'ForestTools' tree top detection

Description

Implements the variable window filter algorithm (Popescu & Wynne, 2004) for detecting treetops from a canopy height model. Andrew Plowright: R package ForestTools

Usage

treepos_FT(
  chm = NULL,
  winFun = function(x) {
     0.5 * ((x^2) * 0.009 + 2.51)
 },
  minTreeAlt = 2,
  maxCrownArea = maxCrownArea,
  verbose = TRUE
)

Arguments

chm	Canopy height model in raster, lasmetrics, matrix or object of class LAS. Should be the same that was used to create the input for treepos.
winFun	function. The function that determines the size of the window at any given location on the canopy. It should take the value of a given CHM pixel as its only argument, and return the desired radius of the circular search window when centered on that pixel.
minTreeAlt	Height threshold (m) below a pixel cannot be a local maximum. Local maxima values are used to define tree tops.
maxCrownArea	numeric. A single value of the maximum individual tree crown radius expected.
verbose	quiet (1) height of treepos.

Value

raster* object

Examples

##- required packages
 require(uavRst)

 data(chm_seg)
 
##- call ForestTools treepos function
 tposFT <- treepos_FT(chm = chm_seg[[1]],
            minTreeAlt = 10,
            maxCrownArea = 150)
            
##- visualize it
# mapview::mapview(tposFT)
raster::plot(tposFT)

gisma/uavRst documentation built on June 25, 2024, 3:07 a.m.