Creating orthomosaic from *.las point cloud in R

Question

Is there a way to export a *.las point cloud in R to a orthomosaic? I loaded my las-file containing the points with the package lidR. I want to export a tif which shows the point cloud from above in RGB, similar to what an orthophoto would look like. The data was collected using a terrestrial laser scanner.

point cloud

this is what I want

This chapter of the book might help you https://jean-romain.github.io/lidRbook/outbox.html#outbox-multispectral-coloring. There is not a single way to achieve that so you must be more specific on how you want to aggregate your point cloud. — JRR, Mar 28 '21 at 19:07

Zoe · Accepted Answer · 2021-03-29T12:29:42.913

1

Okay, so I figured out how to do it, although it's not very elegant:

# load data
points <- readLAS(input_path)

# returns the RGB values for the highest points
RGBZ <- function(r,g,b,z) {
  bands = list(
    R = r[which.max(z)],
    G = g[which.max(z)],
    B = b[which.max(z)]
  )
  return(bands)
}

# create & save ortho
ortho <- grid_metrics(points, ~RGBZ(R,G,B,Z), res = 0.1)
writeRaster(ortho, output_path)

edited Mar 29 '21 at 12:29

answered Mar 29 '21 at 12:20

Zoe

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4
15

You can compute `which.max(z)` only once and your solution will be elegant ;-) – JRR Mar 29 '21 at 19:28

Creating orthomosaic from *.las point cloud in R

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