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Eire/Ireland data is available to buy, and I have a sample file. It seems to be a zip of some files with SHP, PRJ, SHX and DBF extension.

I am trying to convert this data to LAZ format. I can open the file in QGIS, via the browser, but I do not know how to translate/export the data.

I could use either LAZ data or ASC DTM data; Although I need classified LAZ's, I can convert DTM ASC data using RapidLasso lastools to assign ground (2) to the data and force-classify it, and then DemZip.exe to convert format.

I have successfully opened the file in QGIS, and I get a rectangle of block colour. OSI provided a Height.csv file, which I have added as a layer, from a delimited file. The Height file has X,Y,Z and AccurLevel fields, and I have mapped to X,Y and Z accordingly. The rectangle changes colour, and becomes zoomable.

How do I output this to LAS format?

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    Your “ESRI Project” is a shapefile.
    – PolyGeo ♦
    Jun 9, 2021 at 11:22
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    Shapefile is not file geodatabase. If you provide details of what you have attempted, you are more likely to get a response on what needs to change.
    – Vince
    Jun 9, 2021 at 12:18
  • @PolyGeo - Thanks for the explanation. I was assuming it was a project because of the PRJ file. Do you know if it is possible to convert this set of files to raster format, like ASC or DTM format?
    – Steve Hibbert
    Jun 10, 2021 at 12:26
  • @Vince With respect, closing this question seems restrictive and unhelpful. I seek only guidance on how to convert a shapefile into raster format. It occurs to me that other people might be in the same boat as me, and may value an answer to this question. I have added what I have tried so far. Once I get the data in a raster format, I should be good to go, but I do not know how to do that.
    – Steve Hibbert
    Jun 10, 2021 at 12:31
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    LAS/LAZ isn't a raster format, it's a pointcloud format, which is more vector than raster. Passing a shapefile through raster to generate LAS will destroy the benefit of LiDAR collection. GIS SE is problem-solving site; we're not equipped to handle requests for "guidance and links" since these are discussion-oriented and opinion-based.
    – Vince
    Jun 10, 2021 at 12:57

2 Answers 2

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If your shapefile is not a point feature you could convert it to one with a few QGIS vector processing steps like 'Densify by...count/interval' then use SAGA tool 'Convert polygon/line vertices to points'.

Once you have a point feature you could add X, Y columns to the Attribute Table and use the Field Calculator to populate those fields with the Geometry values ($x & $y).

You could then assign your shapefile the height values using the 'Sample raster values' or 'Drape' tools in QGIS (you can find them in the Processing Toolbox, use the search feature there if needed). Name the column with prefix 'Z'.

QGIS processing

Save/export the new point feature as a .csv file. You may have to clean it up a bit to resemble the following format (note no header):

1,410449.469900,1303305.284000,0.199106916785240
2,466992.533900,1297022.722000,0.191032126545906

Then use RapidLasso tool 'txt2las' to finally convert it to LAS.

 C:\LAStools\bin>txt2las64 -i D:\pt.txt -o D:\pt_lidar.las -parse pxyz
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You can convert the shape file into another format (like CSV) using ogr2ogr, then you can use gdal_grid to create a raster.

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  • I have an ESRI shape file (X and Y) and a CSV of height values (Z) that corresponds. The aim is to make either a LAS file, or an ASC file that I can use RapidLasso tools to convert to LAS. Is that possible? Thanks for the response.
    – Steve Hibbert
    Jul 14, 2021 at 11:27

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