Glossary

Plain-language definitions of terms you may encounter while using Lidarvisor.

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Allometric Equation

A mathematical formula that estimates the weight (biomass) of a tree based on easy-to-measure characteristics like height and trunk diameter. Different tree species and regions have different equations. Lidarvisor uses these to calculate carbon stock.

ASPRS

The American Society for Photogrammetry and Remote Sensing. This organization defines the standard classification codes for LiDAR points (e.g., 2 = Ground, 6 = Building). Lidarvisor follows ASPRS standards.

Biomass

The total weight of living material in a tree or area of vegetation. Measured in tonnes or kilograms. "Above-ground biomass" includes the trunk, branches, and leaves. "Below-ground biomass" includes the roots.

CAD (Computer-Aided Design)

Software used by engineers and architects for technical drawing and design. Popular CAD applications include AutoCAD and Civil 3D. Lidarvisor exports DXF files, which are compatible with CAD software.

Carbon Stock

The amount of carbon stored in trees and vegetation, measured in tonnes. Calculated from biomass (approximately 47% of above-ground biomass is carbon). Used in carbon credit projects and environmental assessments.

Catenary

The natural curve that a hanging cable forms between two support points due to gravity. Power lines hang in catenary curves. Lidarvisor models this shape when extracting power line vectors.

CHM (Canopy Height Model)

A raster map showing the height of vegetation above the ground at each location. Calculated by subtracting the DTM (bare ground) from the DSM (top surface). Areas with no vegetation have a value of zero.

Classification

The process of assigning a label (class) to each point in a point cloud — for example, Ground, Building, Vegetation, Water. Lidarvisor does this automatically using AI.

CO2 Equivalent

The amount of carbon dioxide (CO2) that would have the same climate impact as the carbon stored in a tree. Calculated by multiplying the carbon stock by 3.67 (the ratio of CO2 molecular weight to carbon atomic weight).

COPC (Cloud-Optimized Point Cloud)

A modern file format for point clouds that allows software to read only the parts of the file it needs. Built on top of the LAZ compression format. Ideal for web-based viewers and streaming.

Contour Line

A line on a map connecting points of equal elevation. Contour lines show the shape of the terrain — where lines are close together, the slope is steep; where they are far apart, the terrain is flat.

Coordinate System (CRS)

A set of rules that defines how X, Y, Z numbers in a dataset correspond to real positions on the Earth's surface. Different regions and applications use different coordinate systems. Identified by an EPSG code.

Crown (Tree Crown)

The canopy of a tree — the area covered by its branches and leaves as seen from above. In Lidarvisor, a crown is represented as a polygon outline.

DBH (Diameter at Breast Height)

A standard forestry measurement: the diameter of a tree trunk measured at 1.3 meters (4.5 feet) above the ground. Lidarvisor estimates DBH from tree height using allometric equations.

DEM (Digital Elevation Model)

A general term for any raster that represents elevation. Both DTM and DSM are types of DEMs.

DSM (Digital Surface Model)

A raster map showing the elevation of the highest surface at each location — including treetops, rooftops, and other objects above the ground.

DTM (Digital Terrain Model)

A raster map showing the elevation of the bare ground — with all vegetation, buildings, and objects removed. Also called a "bare-earth model."

DXF (Drawing Exchange Format)

A file format for CAD drawings, created by Autodesk. Used to exchange 2D and 3D designs between different CAD software. Lidarvisor exports topographic maps, vectors, and profiles in DXF format.

E57

A file format for storing 3D point cloud data, widely used in BIM (Building Information Modeling) and surveying workflows. Compatible with software like Revit, ReCap, and Cyclone.

EDL (Eye-Dome Lighting)

A rendering technique that adds subtle edge shadows to points in a point cloud, making the shape and depth of the data easier to see. Lidarvisor enables this by default.

EPSG Code

A numerical identifier for a specific coordinate reference system, maintained by the EPSG registry. For example, EPSG:4326 is WGS84 (latitude/longitude), EPSG:32632 is UTM Zone 32N.

GeoJSON

A file format for geographic vector data (points, lines, polygons) based on JSON. Widely used in web mapping and easy to read in any text editor.

GeoTIFF

A TIFF image file that includes geographic metadata (coordinate system, extent, resolution). The standard format for raster geospatial data like terrain models.

GIS (Geographic Information System)

Software for viewing, analyzing, and managing spatial data. Popular GIS applications include QGIS (free) and ArcGIS. Lidarvisor outputs can be imported into any GIS software.

Ground Points

Points in a LiDAR point cloud that represent the surface of the bare earth — not buildings, trees, or other objects.

Hectare (ha)

A unit of area equal to 10,000 square meters (a 100 m × 100 m square), or approximately 2.47 acres. Lidarvisor measures dataset area and credit consumption in hectares.

Hillshade

A visualization technique that simulates sunlight shining on a terrain surface, creating shadows that make the shape of the terrain easier to see. Lidarvisor generates hillshade versions of DTM and TIN terrain models.

Intensity

A property of each LiDAR point representing how strongly the laser signal bounced back from the surface. Hard, reflective surfaces (metal, concrete) typically have high intensity; soft, absorbent surfaces (vegetation, water) have low intensity.

Interpolation

The process of estimating values between known data points to create a continuous surface. When creating a DTM, interpolation fills in the gaps between individual ground points to produce a smooth terrain model.

LAS

The standard file format for storing LiDAR point cloud data. Each point includes X, Y, Z coordinates and may include additional attributes like intensity, color, and classification.

LAZ

A compressed version of the LAS format. Contains the same data as LAS but in a much smaller file (typically 5–10 times smaller). Recommended for storage and transfer.

LiDAR (Light Detection and Ranging)

A remote sensing technology that uses laser pulses to measure distances. A LiDAR sensor emits millions of laser beams per second, measures how long each takes to return, and calculates 3D positions of the surfaces they hit.

NERC FAC-003

A North American regulatory standard (from the North American Electric Reliability Corporation) that requires utility companies to manage vegetation near transmission lines to prevent outages. Lidarvisor's vegetation encroachment analysis supports compliance with this standard.

Noise (in LiDAR context)

Erroneous points in a point cloud caused by sensor errors, atmospheric conditions, birds, or other factors. Noise points do not represent real surfaces and are typically classified as "Low Point" or "High Noise" for removal.

Orthophoto

An aerial photograph that has been geometrically corrected (orthorectified) so that it represents the ground surface accurately, like a map. Can be overlaid on LiDAR data in the viewer.

PLY (Polygon File Format)

A file format for storing 3D data, commonly used in 3D modeling and printing. Compatible with software like Blender, MeshLab, and CloudCompare.

Point Cloud

A dataset consisting of millions or billions of 3D points, each with X, Y, Z coordinates and potentially additional attributes (color, intensity, classification). Created by LiDAR sensors, photogrammetry, or other 3D scanning methods.

Raster

A data format where information is stored in a grid of regularly spaced cells (pixels), like a digital image. Each cell contains a value (elevation, height, slope, etc.). Terrain models are rasters.

RGB

Red, Green, Blue — the three color channels that define a color. In LiDAR, RGB values may be attached to each point if a camera was used alongside the sensor, giving the points natural photo-like colors.

Shapefile

A widely used GIS vector file format developed by Esri. Actually consists of several files (.shp, .shx, .dbf, etc.) typically bundled in a ZIP. Compatible with virtually all GIS software.

Slope

The steepness of the terrain at a given point, typically expressed as a percentage or angle. Lidarvisor's slope map color-codes terrain from flat (green) to very steep (dark red).

Tiling

The process of dividing a large point cloud into smaller, manageable pieces (tiles) that can be loaded progressively in a web viewer. Lidarvisor automatically tiles your data after upload so it can be explored smoothly in the browser.

TIN (Triangulated Irregular Network)

A 3D terrain representation made by connecting points into triangles. Unlike a regular grid (raster), a TIN adapts to the complexity of the terrain — more triangles in detailed areas, fewer in flat areas.

UTM (Universal Transverse Mercator)

A coordinate system that divides the Earth into 60 zones. Each zone uses a local grid measured in meters. Commonly used for LiDAR data because it provides accurate distance measurements over regional areas.

Vector

A data format where features are represented as geometric shapes — points, lines, or polygons — defined by coordinates. Unlike rasters (grids), vectors can represent precise shapes and boundaries. Contour lines, building footprints, and tree crowns are vectors.

Visualization Mode

In Lidarvisor, the method used to color points in the viewer. Options include RGB (original color), Classification (class-based colors), Intensity (grayscale), and Elevation (height-based gradient).

Watershed

An algorithm used in image processing and LiDAR analysis to segment a surface into distinct regions (like water flowing downhill into separate basins). Lidarvisor uses watershed algorithms to identify individual tree crowns.

WebGL

A web browser technology that enables hardware-accelerated 3D graphics without plugins. Lidarvisor's 3D viewer uses WebGL through the CesiumJS library.

WGS84

The World Geodetic System 1984 (EPSG:4326) — the global coordinate system used by GPS. Coordinates are expressed as latitude and longitude in degrees. Lidarvisor converts GeoJSON exports to WGS84 for universal compatibility.

3D Tiles

A format developed by Cesium for streaming massive 3D datasets (including point clouds) in web browsers. Lidarvisor converts your LAS/LAZ files to 3D Tiles for efficient visualization.