Model Export in .las format does not set .las spatial reference system headers

General Feedback & Requests
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1

Hi,
i am currently running into a problem, where i would need the spacial reference headers of my .las export file to be set to my project output coordinate system to let PDAL or other softwares know about the assigned coordinate system.

Reality capture currently only sets the .las header as follows.
When exporting in “grid_plane” the wkt is left empty as expected, but when exporting using “project_output” the wkt is set to the following value:

"wkt": "LOCAL_CS["unnamed",UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Easting",EAST],AXIS["Northing",NORTH]]"

This poses problems for me, as the headers are set, but to a value that is unusable in PDAL…
If i receive a .las file exported by someone else, i have no way of knowing in which coordinate system it is, except them telling me directly.
Is there a way to get the coordinate system of the .las file?

The .las file is exported using the following settings:

<Configuration>
  <entry key="ModelExportFormatVersion" value="0"/>
  <entry key="MvsMeshExportCamerasAsModelPart" value="false"/>
  <entry key="MvsMeshExportTexturingAllowed" value="0"/>
  <entry key="MvsExportScaleZ" value="1.0"/>
  <entry key="MvsExportIsModelCoordinates" value="0"/>
  <entry key="MvsExportIsGeoreferenced" value="0x1"/>
  <entry key="MvsMeshExportNormals" value="false"/>
  <entry key="MvsExportScaleY" value="1.0"/>
  <entry key="MvsExportScaleX" value="1.0"/>
  <entry key="MvsExportcoordinatesystemtype" value="1"/>
  <entry key="MvsMeshExportNormalsAllowed" value="-1"/>
  <entry key="MvsMeshExportNumberFormatAllowed" value="0"/>
  <entry key="MvsExportMoveZ" value="0.0"/>
  <entry key="MvsExportMoveX" value="0.0"/>
  <entry key="MvsExportNormalRange" value="ZeroToOne"/>
  <entry key="MvsExportMoveY" value="0.0"/>
  <entry key="MvsMeshExportInfoFile" value="true"/>
  <entry key="MvsMeshExportByParts" value="0"/>
  <entry key="MvsMeshExportClassificationAllowed" value="-1"/>
  <entry key="MvsMeshExportMaterialsAllowed" value="0"/>
  <entry key="MvsExportRotationY" value="0.0"/>
  <entry key="MvsExportNormalFlipZ" value="false"/>
  <entry key="MvsExportRotationX" value="0.0"/>
  <entry key="MvsExportNormalFlipY" value="false"/>
  <entry key="MvsExportNormalSpace" value="Mikktspace"/>
  <entry key="MvsMeshExportCamerasAllowed" value="0"/>
  <entry key="MvsMeshExportColors" value="true"/>
  <entry key="MvsExportNormalFlipX" value="false"/>
  <entry key="MvsExportTransformationPreset" value="[[Default]]"/>
  <entry key="MvsExportRotationZ" value="0.0"/>
  <entry key="MvsMeshExportFileTypeSelectionDisplay" value="0"/>
  <entry key="MvsMeshExportClassificationLayer" value="-1"/>
</Configuration>

Similar Problem with xyz export:

2

Hello Manik,
where are you checking the LAS header? Was your system set to IGS97?

3

i check the header of the exported .las file using PDAL

pdal info --metadata model.las

The project output coordinate sytem and the output coordinate system are both set to WGS84 in reality capture

I found this error because I wanted to apply a reprojection with PDAL. When I don’t specify an input SRS, the reprojection filter reads the input SRS from the last metadata. But I get the error message below in the case of las files exported from Reality Capture. Of course, I could overwrite the in SRS with PDAL, but it would be nice if it were already correct in the exported LAS file. For instance, las files from the DJI Lidar drones already come with the correct SRS in the metadata, such that I don’t need to overwrite the input SRS.

ERROR 6: Cannot find coordinate operations from

{
  "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
  "type": "EngineeringCRS",
  "name": "unnamed",
  "datum": {
    "name": "Unknown engineering datum"
  },
  "coordinate_system": {
    "subtype": "Cartesian",
    "axis": [
      {
        "name": "Easting",
        "abbreviation": "",
        "direction": "east",
        "unit": "metre"
      },
      {
        "name": "Northing",
        "abbreviation": "",
        "direction": "north",
        "unit": "metre"
      }
    ]
  }
}

to ‘EPSG:25832’

4

Thank you for this report, I created a bug and notified our developers about it.
We are sorry for the inconveniences.

5

Thank you for the quick response!