Dear Researchers, <br><br>I wrote a code in R to processing around 1.2 GB of laser data derived by a Terrestrial Laser Scanning in a forested area. There are few techniques to derive a DEM from the ground points. One is create a grid of 0.5 x 0.5 m and give for each pixel the minimum Z value of the points inside the voxel (0.5 x 0.5 m by the Hmax of vegetation). Normally, In this ground points there are a component of outlier. The normal techniques proposed are:<br>
<br><br><img alt="Inline image 1" src="cid:ii_1386bc9eb89f76a7"><br><br><br><br>1. remove manually<br>2. special filter based on the angle of neighboured points <br>3 . RANSAC <br><br> I used locoutNeighbor of library(mvoutlie) with good result using these set parametrs:<br>
<br>Myres <- locoutNeighbor(as.matrix(ppZmin.df.clean$z),ppZmin.df.clean$x,ppZmin.df.clean$y,<br> variant="knn",<br> usemax=1,<br> chisqqu=0.999,<br> propneighb=1,npoints=nrow(ppZmin.df.clean))<br>
<br><br>I just make some try yesterday night <br><br><img alt="Inline image 2" src="cid:ii_1386bcbf00256579" height="481" width="381"><br><br>I am interest to comapre on my data more Outlier removing techniques and any suggest is really appreciate<br>
<br>Thanks in advance<br>Gianni<br><br><br><br><br><br><br><br>