waveformvoxel: waveformvoxel

In waveformlidar: Waveform LiDAR Data Processing and Analysis

Description

The function allows you to project raw waveforms into 3d voxels from hyperpointcloud with self defined resolution. For the intensity of each grid, four kinds of values were available to be used: the total number of intensity in each voxel, maximum intensity of the voxel, mean intensity of the voxel, and total intensity of the voxel.

Usage

waveformvoxel(hpc, res = c(0.8, 0.8, 0.15), quan = NULL)

Arguments

hpc	the objetcs from hyperpointcloud function.
res	the voxel size with x, y, and z spatial resolution. Default is 0.8*0.8*0.15.
quan	The quantile of intenisty in the given grid or voxel. Defalut is NULL.

Value

A dataframe with 7 columns including geolocation and intensities. Specifically,"index","cx","cy","length_maxi_meani_totali.1","length_maxi_meani_totali.2", "length_maxi_meani_totali.3","length_maxi_meani_totali.4").

index	The index of the voxel
cx	The average x of the voxel center
cy	The average y of the voxel center
cz	The average z of the voxel center
intensity.length	The number of intensity in the voxel
intensity.maxi	The maximum intensity of waveforms in the voxel
intensity.meani	The mean intensity of waveforms in the voxel
intensity.totali	The total intensity of waveforms in the voxel
...	Percentile intensity based on the quan

References

Tan Zhou, Sorin Popescu, Lonesome Malambo, Kaiguang Zhao, Keith Krause. From LiDAR waveforms to Hyper Point Clouds: a novel data product to characterize vegetation structure. Remote Sensing 2018, 10(12), 1949; https://doi.org/10.3390/rs10121949

Examples

data(return)  ###import raw return waveforms
data(geo)  ###import corresponding reference geolocation

#' ### you should know which columns corresponding to above column names
## before run the hyperpointcloud when you used your own new datasets, this is very important step
colnames(geo)[2:9]<-c("x","y","z","dx","dy","dz","or","fr")

hpr<- hyperpointcloud(waveform = return,geo = geo)

##beofre run waveformvoxel, we need to create hyperpointcloud first
##this exampel we just used 100000 points to reduce processing time

voxr<-waveformvoxel(hpc = hpr,res=c(1,1,0.3))

waveformlidar documentation built on Aug. 1, 2020, 5:07 p.m.