Retrieve individual pulses, flightlines or scanlines
Retrieve each individual pulse, individual flightline or individual scanline and assigns a number to each point. The LAS object must be properly populated according to LAS specifications otherwise users could find unexpected outputs.
retrieve_pulses(las) retrieve_flightlines(las, dt = 30) retrieve_scanlines(las)
las |
A LAS object |
dt |
numeric. The threshold time-lag used to retrieve flightlines |
retrieve_pulsesRetrieves each individual pulse. It uses GPS time. An attribute
pulseID is added in the LAS object
retrieve_scanlinesRetrieves each individual scanline. When data are sampled according to a
saw-tooth pattern (oscillating mirror), a scanline is one line, or row of data. The function relies
on the GPS field time to order the data. Then, the ScanDirectionFlag attribute is used to
retrieve each scanline. An attribute scanlineID is added in the LAS object
retrieve_flightlinesRetrieves each individual flightline. It uses GPS time. In a
continuous dataset, once points are ordered by GPS time, the time between two consecutive points
does not exceed a few milliseconds. If the time between two consecutive points is too long it means
that the second point is from a different flightline. The default threshold is 30 seconds.
An attribute flightlineID is added in the LAS object.
An object of class LAS
LASfile <- system.file("extdata", "Megaplot.laz", package="lidR")
las <- readLAS(LASfile)
las <- retrieve_pulses(las)
las
las <- retrieve_flightlines(las)
#plot(las, color = "flightlineID")Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.