Using an array of overlapping images, such as those collected using a drone, this tool generates a high-density point cloud based on user-selectable parameters. Employing the principles of photogrammetry in which measurements are derived from photographs, the Pixels-to-Points tool analyzes the relationship between recognizable objects in adjacent images to determine the three-dimensional coordinates of the corresponding surface. As a by-product of the point cloud generation capability, the Pixels-to-Points tool also offers the option of creating an orthorectified image, which effectively stitches the images together and adjusts them to reflect the inherent three-dimensional coordinates.
Quickly reclassify points with seven different classification types.
Automatically reclassify buildings, trees, ground points and above-ground utility cables with conveniently located button in the LiDAR tool bar. The Global Mapper LiDAR Module features improved classification to filter out likely buildings, trees and power lines along with additional parameters controls in the Ground Classify dialog. Machines with multiple cores will experience faster automatic classification of ground points. The user can also perform automatic classification on just selected points to speed up processing.
The LiDAR module offers an array of tools for improving the quality of a point cloud. Points can be manually or automatic reclassified, cropped to the extent of an area of interest and noise points can be automatically identified and removed. The vertical accuracy of the data can be validated against surveyed control points and adjusted if needed.
Access the LiDAR filtering options from the "Options" tab in the "Configuration Window" to allow easily filtering by classification and/or return type. Filter LiDAR points by class, elevation, color, scan-angle, source-ID, intensity, height-above-ground, NDVI and NDWI (when available), and return type when exporting, gridding, and selecting from point clouds.
Feature extraction allows the user to render buildings, trees and power lines for greater visualization of LiDAR data. This new and powerful feature in Global Mapper is something normally only seen in software that costs thousands of dollars for a single user license. The Global Mapper Lidar module enables users to easily and quickly conduct feature extraction rendering appropriately classified lidar points as 2D and 3D feature objects. This powerful data will assist users that wish to create better and more exact earth models with realistically representative objects.
Using the new Perpendicular Path Profile function, a series of custom spaced cross-sectional views are created perpendicular to a defined path through a point cloud. 3D vertices can be quickly and accurately placed at regular intervals within each successive profile view. When the sequence is complete, either a 3D linear or area feature is created using Global Mapper's standard Digitizing tool. This is an ideal tool for delineating curbs, utility cables, pipelines, drainage ditches, or building rooflines from high-resolution point cloud data.
The display of points can be adjusted to reflect many of the attributes within the point cloud, including:
When overlaid on a raster or gridded layer, the RGB or NIR value from each underlying pixel can be added to the associated point.
With robust gridding techniques for faster, extremely flexible creation of elevation surfaces, including smart decimation through binning, and other techniques.
The module also includes the ability to leverage the LiDAR toolbar directly in the Path Profile viewer for faster management, editing and reclassifying of points. The module includes two selection options for selecting points in the Path Profile viewer, to select by a click and drag method or selection by drawing a custom polygon to select points.