THE FILE FIELD GUIDE

.las

LAS Point Cloud

Maps & GPS

LAS is a point-cloud exchange format, potentially holding intensity, classification and returns alongside XYZ. It is not an image; inspect coordinate system, scale and point-record version before import.

Main use: Store 3D LiDAR points and attributes
Data type: Binary data

All sections, questions and sources

Content reviewed：2026-10-19 · Editor：Kai

Opening steps

Choose your environment or purpose to see its steps.

PDAL / LAS-capable point-cloud software

Preserve the original and inspect a working copy in a compatible application.

Load a copy in LAS-capable point-cloud software.
Inspect point count, bounds, classes and available attributes.
Establish horizontal/vertical references and display the required region.

Inspect the received file and its requirements

Establish dependencies and settings before proceeding.

Inspect LAS version and point format.
Check CRS, units, scale/offset and vertical datum.
Verify that desired attributes such as RGB actually exist.

Menu labels and support vary by app, OS and version. Preserve the original before making changes.

Troubleshooting by symptom

Map misalignment: inspect horizontal/vertical references and units.
No color: check for RGB and the selected coloring attribute.
Reader fails: compare LAS/point formats with tool support.
Coordinate precision changes: inspect output scale/offset.

LAS → LAZ / subset point cloud

Export selected points/attributes to LAZ or another point format, recording any coordinate transformation.
Verify point count, bounds, CRS and required attributes after export.

XYZ-only tables lose classifications/returns; assigning a CRS label is not transforming coordinates.

CRS versus scale and offset

Scale/offset decode stored coordinates, while a CRS describes their spatial reference. Relabeling is not proof of corrected position; compare known locations and values.

Source for these steps：PDAL project · readers.las / PDAL project · writers.las

Worked example: checks before handoff

Example: compare total/classified point counts and known coordinates before and after producing a road LAZ dataset.

Source for these steps：PDAL project · readers.las / PDAL project · writers.las

Related-format differences

Related-format differences
Format / method	Purpose and preserved information
.las	Store 3D LiDAR points and attributes
LAZ / XYZ table	LAZ is compressed point data; XYZ tables retain a different attribute set.
LAS → LAZ / subset point cloud	XYZ-only tables lose classifications/returns; assigning a CRS label is not transforming coordinates.

Handling and security

Point clouds can disclose precise locations/facilities; review survey-data sharing conditions.

Questions and answers

Is LAS a photograph?

It is a set of 3D points/attributes; photo-like color is not guaranteed.

How does LAZ differ?

LAZ is used for lossless LAS compression and requires decoding support.

Does assigning a CRS transform coordinates?

Assignment and transformation differ; verify interpretation against known locations.

Format facts: name, steward and MIME type

Formal name: LAS Point Cloud
Steward / specification: PDAL project
MIME type: Consult the producer or delivery system. The extension alone does not establish a MIME type.

Primary and official sources

Software documentationreaders.las
Reading LAS/LAZ, point attributes and record formats.
PDAL project · Link checked：2026-10-16
Software documentationwriters.las
Coordinate scale/offset, versions and output attributes.
PDAL project · Link checked：2026-10-16