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Converting waveform LiDAR to discrete return format, in R?


I have an LVIS waveform LiDAR file which looks like this:

head(lidar) V1 V2 V3 V4 V5 V6 V7 V8 V9 [1,] 529437.4 4966194 0.000608380 0.000067737 0.000212176 0.000171945 0.000062599 0.000913602 0.001354659 [2,] 529401.1 4966205 0.000574129 -0.000083901 0.000598198 -0.000124780 0.001289195 -0.000069118 0.001239798 [3,] 529421.0 4966211 0.001361471 0.000759721 0.002047902 0.001531523 0.000785660 0.000718898 0.001417265 [4,] 529441.0 4966216 0.001550620 0.001439063 0.001425855 0.001602712 0.002766050 0.001392409 0.001316686 [5,] 529429.3 4966235 0.001218291 0.000860475 0.000587853 0.000646795 0.000652875 0.000569392 0.001172389 [6,] 529409.2 4966229 0.000363583 0.001409501 0.000631517 0.000835653 0.000849753 0.000280018 0.000865165 V10 V11 V12 V13 V14 V15 V16 V17 [1,] 0.000707322 0.000922818 0.000865636 0.000487058 0.000429923 0.000910006 0.001296637 0.000787348 [2,] 0.000653536 0.000597434 0.000572901 0.001305983 0.000599163 0.001322806 -0.000088809 0.001266157 [3,] 0.001407048 0.002147792 0.000798765 0.001396288 0.001446622 0.001452398 0.001384238 0.002826389 [4,] 0.000155622 0.001480598 0.000775280 0.001507099 0.001487691 0.001259001 0.000203995 0.001371990 [5,] 0.001352416 0.001410255 0.000734748 0.001138494 0.001381453 0.001323874 0.001337453 0.001337283 [6,] 0.000906885 0.000114350 0.001470484 0.000979770 0.001269763 0.001143270 0.000623536 0.001674105 > str(lidar) num [1:12414, 1:153] 529437 529401 529421 529441 529429… - attr(*, "dimnames")=List of 2… $ : NULL… $ : chr [1:153] "V1" "V2" "V3" "V4"…

Column V1 is the X coordinate and column V2 is the Y coordinate.

The rest of the columns (3-153) represent the waveforms.

How do I convert this data to a discrete return LiDAR format (or to something approximating discrete return format), one with x, y, and z columns representing the X coordinate, Y coordinate and elevation?

I ask because my goal is to visualize this data inrglpackage, hence why I hope to find a solution in R. But I am opened to use a different tool, if not possible with R.

The CSV file of waveform LiDAR data is available for free download here.

I think the values in columns 3-153 are small because they represent a 'standardized signal'. See the attached image.


Full waveform LiDAR is still an evolving field with very few software being available. However, the PulseWaves API and tools are able to read the original LVIS files (that are binary and not in CSV format). The best place to inquire about full waveform LiDAR is in this discussion forum here: http://pulsewaves.org


Watch the video: LiDAR Remote Sensing Part 3: Data Analysis (October 2021).