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 in rgl
package, 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.