Changes between Version 1 and Version 2 of Processing/LidarNoisyPoints


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Timestamp:
Feb 21, 2012 5:27:15 PM (7 years ago)
Author:
mark1
Comment:

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  • Processing/LidarNoisyPoints

    v1 v2  
    11= Post Processing LiDAR Point Clouds=
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    3 The usual form of delivery of the processed LiDAR data is in the form of a point cloud. This takes one of two forms; [link ASCII text files] or [http://www.asprs.org/Committee-General/LASer-LAS-File-Format-Exchange-Activities.html binary LAS] files. As part of the standard processing and quality checking of the LiDAR point clouds, ARSF-DAN classify 'noisy' points. This is done both by using automatic algorithms and by viewing the data. The noisy points can be one of the following:
     3The usual form of delivery of the processed LiDAR data is in the form of a point cloud. This takes one of two forms; [link ASCII text files] or binary [http://www.asprs.org/Committee-General/LASer-LAS-File-Format-Exchange-Activities.html LAS] files. The point clouds contain all the LiDAR data as vectors, a list of individual points, rather than as rasterised data.
     4
     5== Removing Noise Points ==
     6
     7As part of the standard processing and quality checking of the LiDAR point clouds, ARSF-DAN classify 'noisy' points. This is done both by using automatic algorithms and by viewing the data. The noisy points can be one of the following:
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    59 * isolated points
     
    913 * system noise
    1014
    11 It is advised that these points be removed before using the data, unless they are of specific use to your studies.
     15When a point has been identified as being 'noise' it is given a classification value of '7'. All other points will probably have classification of '0' (unclassified) or '1' (default). The classification values used follow the ASPRS standard LiDAR point classes.
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    13 == Removing Noise Points ==
     17It is advised that these points be removed before using the data, unless they are of specific use to your studies. ARSF-DAN included a utility for removing these points from the ASCII files called 'pt_cloud_filter'. To remove them from LAS files it is suggested to download the LASTools package, specifically the las2las tool.
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    15 When a point has been identified as being 'noise' it is given a classification value of '7'.
     19=== Removing noisy points from ASCII files ===
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     21
     22=== Removing noisy points from LAS files ===