Write LAS or LAZ files

Write a LAS or LAZ file at any step of the pipeline (typically at the end). Unlike other stages, the output won't be written into a single large file but in multiple tiled files corresponding to the original collection of files.

Usage

write_las(
  ofile = paste0(tempdir(), "/*.las"),
  filter = "",
  keep_buffer = FALSE
)

write_copc(
  ofile = paste0(tempdir(), "/*.copc.laz"),
  filter = "",
  keep_buffer = FALSE,
  max_depth = NA,
  density = "dense"
)

Arguments

ofile

character. Output file names. The string must contain a wildcard * so the wildcard can be replaced by the name of the original tile and preserve the tiling pattern. If the wildcard is omitted, everything will be written into a single file. This may be the desired behavior in some circumstances, e.g., to merge some files.

filter

the 'filter' argument allows filtering of the point-cloud to work with points of interest. For a given stage when a filter is applied, only the points that meet the criteria are processed. The most common strings are Classification == 2", "Z > 2", "Intensity < 100". For more details see filters.

keep_buffer

bool. The buffer is removed to write file but it can be preserved.

max_depth

integer. Maximum depth of the hierarchy. Default is NA meaning that is auto computes

density

character. Can be 'sparse', 'normal' or 'dense'. It controls the point density per octant. With 'sparce' each Octree octant is subdivided into 64 x 64 x 64 cells which mean that the density of point is light. Normal is 128, dense is 256.

Details

`write_las` can write a COPC LAZ file simply by naming the output file with the ".copc.laz" extension. However, users must be cautious. Writing COPC is not optimized for memory usage and requires two copies of the point cloud in memory to ensure proper sorting and writing. If the user cannot afford to keep two copies of the point cloud in RAM, they should use a more specialized writer such as Untwine (PDAL) or lascopcindex (LAStools).
`write_copc` is a wrapper around `write_las`, with a few extra arguments to control the COPC format.

Examples

f <- system.file("extdata", "Topography.las", package="lasR")
read <- reader()
tri  <- triangulate(filter = keep_ground())
normalize <- tri + transform_with(tri)
pipeline <- read + normalize + write_las(paste0(tempdir(), "/*_norm.las"))
exec(pipeline, on = f)
#> [1] "/tmp/RtmpdMMS1f/Topography_norm.las"