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Last Post 15 Jan 2018 09:38 AM by  Mari Minari
ENVi Lidar--estimating tree heights
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Jessica M.



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04 Jan 2018 03:56 PM
    I am a M.S. student and plan on using ENVI Lidar as part of my thesis research in estimating tree height/canopy cover from Lidar data.
    I am not sure if the information is proprietary, but is there a way to find out/better understand how ENVI Lidar calculates the tree heights as part of processing the data? I cannot seem to find information on the algorithm.
    Any information would be helpful and thank you!

    Mari Minari



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    15 Jan 2018 09:38 AM
    The equations are proprietary but here is a high level description that might be helpful:
    • Points are classified as terrain, building, powerline or tree (vegetation)
    • The vegetation points are analyzed to find tree crowns by finding the highest vegetation point in a local area and checking if the points slope downward and outwards from this point. This calculation yields the crown center and radius.
    • Where a tree crown was detected the ground height under it is determined from the DEM and the tree height calculated by subtracting the ground height from the highest point in the tree crown.
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