Help Specifying datum in WKT

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guy.m...@dnr.wa.gov

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May 6, 2021, 9:53:45 AM5/6/21
to LAStools - efficient tools for LiDAR processing
I have many lidar projects in version 1.4 format, that have been re-projected.
The original WKT header has the Datum information and vertical units specified in the only VLR.

variable length header record 1 of 1:
  reserved             0
  user ID              'LASF_Projection'
  record ID            2112
  length after header  915
  description          'WKT Projection'
    WKT OGC COORDINATE SYSTEM:
    COMPD_CS["NAD83(2011) / UTM zone 10N + NAVD88 height - Geoid12B (meters)",PROJCS["NAD83(2011) / UTM zone 10N",GEOGCS
["NAD83(2011)",DATUM["NAD83 (National Spatial Reference System 2011)",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORIT
Y["EPSG","7019"]],AUTHORITY["EPSG","1116"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199
433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","6318"]],PROJECTION["Transverse_Mercator"],PARAMETER["latitude_of_origin"
,0],PARAMETER["central_meridian",-123],PARAMETER["scale_factor",0.9996],PARAMETER["false_easting",500000],PARAMETER["fal
se_northing",0],UNIT["meter",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","6339"]],VERT_C
S["NAVD88 height - Geoid12B (meters)",VERT_DATUM["North American Vertical Datum 1988",2005,AUTHORITY["EPSG","5103"]],UNI
T["meter",1,AUTHORITY["EPSG","9001"]],AXIS["Up",UP],AUTHORITY["EPSG","5703"]]]

Once I project it from UTM to WA State Plane, I define a Geotiff for the projcetion, and specify the vertical Units.  I use -set_ogc_wkt to create the WKT.  But I have lost the datum information, and the vertical units are unrecognized in ESRI products.

variable length header record 1 of 2:
  reserved             0
  user ID              'LASF_Projection'
  record ID            34735
  length after header  40
  description          'by LAStools of rapidlasso GmbH'
    GeoKeyDirectoryTag version 1.1.0 number of keys 4
      key 1024 tiff_tag_location 0 count 1 value_offset 1 - GTModelTypeGeoKey: ModelTypeProjected
      key 3072 tiff_tag_location 0 count 1 value_offset 32149 - ProjectedCSTypeGeoKey: NAD83 / Washington South
      key 3076 tiff_tag_location 0 count 1 value_offset 9003 - ProjLinearUnitsGeoKey: Linear_Foot_US_Survey
      key 4099 tiff_tag_location 0 count 1 value_offset 9002 - VerticalUnitsGeoKey: Linear_Foot
variable length header record 2 of 2:
  reserved             0
  user ID              'LASF_Projection'
  record ID            2112
  length after header  758
  description          'by LAStools of rapidlasso GmbH'
    WKT OGC COORDINATE SYSTEM:
    PROJCS["NAD83 / NAD83 / Washington South",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","6269"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],PROJECTION["Lambert_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",47.3333333333333],PARAMETER["standard_parallel_2",45.8333333333333],PARAMETER["latitude_of_origin",45.3333333333333],PARAMETER["central_meridian",-120.5],PARAMETER["false_easting",1640416.66666677],PARAMETER["false_northing",0],UNIT["US survey foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],AXIS["Easting",EAST],AXIS["Northing",NORTH],AUTHORITY["EPSG","32149"]]

Is there a way within LASTools to retain the datum information?   Put it back in?  And get the VERT Units specified?
Or will I have to get into writing GDAL scripts if I need to do this?

Any help greatly appreciated!
Guy McWethy

Martin Isenburg

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May 9, 2021, 8:29:45 AM5/9/21
to LAStools - efficient command line tools for LIDAR processing
Could you provide a small example of such a LAZ file (as a link, not as an attachment) before the transform together with the las2las command that you use for the transform?

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