183 articles Terrasolid Tools, Tips and Workflows Page 2 / 19

Classifying by Groups in TerraScan

Beginning in 2014, some grouping tools were introduced to TerraScan.  Those tools applied to mobile LIDAR applications as they were aimed at classifying moving cars and trees. In late 2016, additional grouping tools were introduced to enable a new method of conducting above ground classifications in airborne LIDAR datasets beyond the standard classification routines.  Prior…

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Edit Several Blocks

It is possible to edit the definition of multiple blocks in a project simultaneously. In the Project Window, simply select multiple blocks and selected ‘Edit definition’ for the ‘Block’ drop down menu. When more than one block is selected then the ‘Edit definition’ tool becomes an ‘Edit several blocks’ tool that can be used to change…

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Loss of VLR information by TerraScan

With the release of TerraScan v017.001 for CE, TerraScan should now be preserving the projection VLR information in the LAS header. However, when processing with TerraScan, either directly or indirectly through GeoCue, there are some scenarios in which VLRs can be stripped from your data, or at least appear to be removed. Scenario 1: Reading…

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Tie Line Statistics in TerraMatch

Terrasolid products provide statistical information about the fit of LIDAR and imagery data. This article is the second in a series that provides meaning to this type of information. We will conduct a brief review of the relevant statistics and discuss how these principles are applied to the use of tie lines for laser calibration.…

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Setting the USGS Overage Flags in TerraScan

Introduction For many years users have been working with the concept of ‘cutting overlap’ in LIDAR data production. With the onset of LAS v1.4 and the USGS LIDAR Base Specification, the way in which this concept is implemented has significantly changed.  Specifically, USGS standards require a change in the way overlap points are managed and…

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Create as Profile Model

In the Triangulate Surface dialogue there is a new “Create as Profile Model” option. The “Create as Profile Model” option appears when you have an element selected when you Triangulate Elements. The “create as a profile model” option allows you to create a surface from a single vector element. This allows you then to use…

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Apply Correction is Very Slow

Symptom: Applying tie line fluctuation corrections using TerraMatch, either on loaded points, project points, or by using the Apply Corrections macro step runs very slow. Probable Resolution: Apply correction takes a long time if the points are not sorted by time stamp. The Apply correction process computes the scanner position for small intervals of consecutive time…

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Intensity Custom vs Automatic Coloring

Color by Intensity custom/auto settings display the points according to their intensity value. The default grey scale of TerraScan stretches from dark grey for low intensity values to white for high intensity values. Intensity auto uses a more homogeneous grey-scale coloring scheme. The intensity values are fitted to the grey values of the coloring scheme…

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TerraScan LAS v1.4 Flagged classes

TerraScan’s implementation of flags on classes show in all tools and routines as a classification number. It can be handy to know how the classes correspond with the classification code and classification flags of the LAS v1.4 specification to better understand how to quickly modify your routines, macros, tool buttons, etc. Table 1 – TerraScan LAS v1.4 Classes Class…

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Control Point Statistics in TerraScan

Terrasolid software offers a variety of ways to gauge the accuracy of LIDAR and imagery data.  From using control points to determine the vertical accuracy of a ground surface, tie lines to measure and correct the mismatch between overlapping flight lines, and tie points to correct aerial imagery positions, each of these tools provide the…

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