I have a LiDAR .laz file with points from Toulouse (France). I convert this file to a .las file using LAStools's las2las function. Then, using lasinfo on this .las file gives me some information, including:

GeoKeyDirectoryTag version 1.1.0 number of keys 3
  key 1024 tiff_tag_location 0 count 1 value_offset 2 - GTModelTypeGeoKey: ModelTypeGeographic
  key 2048 tiff_tag_location 0 count 1 value_offset 4326 - GeographicTypeGeoKey: GCS_WGS_84
  key 4099 tiff_tag_location 0 count 1 value_offset 9001 - VerticalUnitsGeoKey: Linear_Meter

So, I assume that my data is in the WGS84 format.

Regarding points, I have this information using lasinfo on my .las file:

scale factor x y z:         0.001 0.001 0.001
offset x y z:               1574926.999698425875977 3157519.458761402405798 142.690597958476445
min x y z:                  1574775.710 3157384.005 125.497
max x y z:                  1574981.625 3157614.866 226.186

Looking, for exemple, at the minimum point which should be located in Toulouse: (1574775.710, 3157384.005) and following the .las documentation, my real point is :

Xcoordinate = (Xrecord * Xscale) + Xoffset
Xcoordinate = (1574775.710 * 0.001) + 1574926.999698425875977 = 1576501.774698425875977
Ycoordinate = (3157384.005 * 0.001) + 3157519.458761402405798 = 3160676.842761402405798

However, as I saw on many sources, WGS_84 should be between [-90, 90] and [-180, 180], right ?

I saw this question on the forum that may be related to my problem, but even playing with the 3second-->100m that he talks about, I can't find any way to go from my data point (1574775.710, 3157384.005) to the (43.603266, 1.442261) latitude/longitude point that Google Maps gives me for Toulouse in France.

Capitole, Toulouse, France

1 Answer 1


I finally managed to solve my problem.

The weird thing is that the coordinates inside my .laz file weren't projected using WGS_84 but CC44. I still don't know why it was written GCS_WGS_84 in the lasinfo return.

An other thing that mistook me was that scaling and adding the offset gave me a less precise result than taking the raw min coordinate given by lasinfo. That's because those min and max coordinates are already scaled and translated when given by lasinfo.

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