Using LiDAR Data within Smallworld

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Using LiDAR Data within Smallworld

• Mark Field FCSI

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Overview

• LiDAR We have heard about it, but what is it?
• Hows it collected
• What data is in it
• Variations of LiDAR data
• How is it stored in Smallworld
• Example set of tools
• How this implementation can be used to develop
  useful data

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What is LiDAR?

• Light Detection And Ranging
• aka Laser Detection And Ranging (LADAR)
• Can be used in side and downward-looking
• Laser speed gun, weather radar, airborne
• Data is gathered by detecting the reflection of
  the light
• Distance, intensity, return number
• Raw results are point clouds

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LiDAR Collection Illustration
Source https//www.e-education.psu.edu/lidar/node
/1405
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Variations of LiDAR

• Raw, Unfiltered Data(LAS format)
• Contains noise, artifacts
• Filtered, Classified (LAS format)
• Contains point cloud data
• Multiple returns
• Classified into ground, vegetation, building,
  etc.
• Ground Points (LAS format)
• Contains single layer of ground
• Digital Elevation Models (DEM, DTM, TIN)
• Rasterized version of ground points

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Variations of LiDAR (cont.)

• LAZ
• Lossless Compressed LAS
• Categorized XYZ
• ASCII
• Files separated into single category

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Implementation by FCSI

• Expanded FCSIs N-Dimensional Geometry
• 5 Dimensional TIN Structure (XYZTV)
• TIN Node now contains all LiDAR Data

• X, Y, Z
• Intensity
• Return
• Number of Returns
• Scan Direction
• GPS Time

• Edge of Flight?
• Classification
• Scan Angle
• User Data
• Point Source
• Color (RGB)

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Example Tools by FCSI

• Point Viewer
• Points colored by return, intensity, elevation,
  classification
• Filter points by return, intensity,
  classification
• DEM Updater
• Update DEM values based off LiDAR
• Manual Feature Extraction

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Point Viewer
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DEM Update
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Elevation Extraction
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Issues with LiDAR

• Number of Points is extremely large
• 1000 x 100 of Missouri contains 560,000
  points!
• 5000 x 5000 5.3 to 8.2 Million points!
• 5.3 Million 463MB gdb.ds (1MB rwo.ds)
• What will it be used for?
• DEM/TIN Rasterize externally
• Ensure data is what you want to use
• Is it classified?
• Does it contain non-ground data (multiple
  returns)?
• External tools do exist that may be more effective

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How Can LiDAR Be Used?

• Very accurate terrain models
• TINs or DEMs
• Identify features for corridor management
• Buildings
• Vegetation
• Towers, Poles, Lines

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Questions?/Contact

• Mark Field
• mark_at_field-csi.com
• FCSI Booth 19
• Cell 407-376-6105
• _at_mbfbsae90
• mbfbsae90