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5

For running LASzip from the command prompt window it is also necessary to specify the path of the input file. For example, suppose the laszip.exe file is installed under the drive D: (D:\LASzip\laszip.exe) and that the .laz files are stored in D:\lidar. Then, type: D:\LASzip\laszip D:\lidar\*.laz It will decompress all LAZ files in the current folder ...


3

This is because csc.noaa.gov lidar files are stored with the .laz file format extension. It is a compressed version for .las extension. Read this* article to know more about compressed las files (.laz). In order to correctly visualize these types of files, you need to retransform them from .laz to .las. Use the open-source LiDAR compressor LASzip to ...


3

A convenient way to get point cloud data to Python is to use the PDAL Python extension. PDAL uses the concept of pipelines (much like a GDAL VRT for point clouds instead of rasters) to allow users to orchestrate the processing of point cloud data. With the PDAL Python extension, you can read a LAZ file into a Numpy array and then do whatever you need to ...


2

One caveat to using FUSION: it truncates the precision of the output coordinates to only 4 decimal places, and I required 6. I really wanted to use WhiteBox GAT, however I was unable to get it to perform the nearest-neighbor processing (it kept insisting that the units from my files were in meters, not decimal degrees) I ended up using SAGA GIS on the ...


2

The sample record you show is in projected coordinates and the two values for longitude and latitude listed in the Coordinate Reference System (CRS) are part of the parameters that defined the projection that was used, here a particular Transverse Mercator projection that is called "SVY21 / Singapore TM" and is centered near Singapore. You can use the latest ...


2

I can see no technical reason for ESRI's creation of zLAS. A decision was made that - as far as I understand - was quite heavily contested even within the ESRI management to create a format under their control. There was a big outcry by the Open Source Geospatial Consortium (OSGeo). At the time a number of misleading statements were circulated that are ...


2

Esri does support the ASPRS .las format through the latest version, 1.4. The LAS format is a pretty simple format. It doesn't support indexing or statistics on the data. For instance, the LAS header doesn't include what class codes are in the file. You have to completely scan the file to discover them. The presenter in the video referenced below mentions ...


2

This file is strange. First, an EPSG code of 0 isn't valid. LOCAL_CS["unnamed",AUTHORITY["EPSG","0"]] Second, SMRF is designed for aerial LiDAR data, not this (bridge superstructure?). Third, there's a bug in the SMRF knn code that is triggered by this particular point configuration. Please follow https://github.com/PDAL/PDAL/issues/2794 for details.


2

https://github.com/hobu/laz-perf contains an alternative implementation of LASzip that can be compiled to WASM and JavaScript using Emscripten. It is used by Potree and PlasioJS to provide LAZ support in JavaScript.


1

Use Fusion's LTKProcessor to speed up performance of PolyClipData. It is described in Appendix C from Fusion's manual (emphasis mine): Using LTKProcessor to Process Data for Large Acquisitions LTKProcessor is designed to facilitate the application of FUSION-LTK tools to large data acquisitions. It uses multiple data files to create seamless data ...


1

Yes, you spotted a bug which we have fixed a few days ago (commit reference). Simply reinstall the r.in.pdal command with g.extension to fetch the updated version.


1

There are things you can do to the files before you compress them to make the LAZ compression more efficient. Sort them based on GPSTime if you have that attribute. Sort them along a space-filling curve if you don’t. Zero out attributes you don’t need. If you have color information in raster data elsewhere, it will be much more efficient to compress them ...


1

To answer your first question: No. The tools and supporting documentation over at LASzip.org covers the details. A lossless compression is absolutely critical with LAS data and this group has ASPRS official support afaik. To answer your second question: No. Though you really ought to have tried that yourself. Also, 7zip is no improvement over WinZip, etc.


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The way I see liblas installed from brew, it does not include flags WITH_LASZIP or WITH_STATIC_LASZIP on build. See: https://github.com/Homebrew/homebrew-core/blob/master/Formula/liblas.rb


1

It is always a good idea to check any new LiDAR in LAS or LAZ format with the LAS validator tool as this will report any warnings or - more severe - failures in the file's adherence to the ASRPS specification. Also and read or decompression errors (e.g. due to rare bitflips and more common file truncations) will become obvious. You also find the free and ...


1

As mentioned by Aaron, the CanopyModel tool from Fusion can build Digital Surface Models (DSM). In order to directly use the compressed LiDAR files .laz as input of CanopyModel, it is necessary to have the file LASzip.dll from LASzip program installed within Fusion's install folder.* By default the CanopyModel will assign the elevation of the highest ...


1

Check this tutorial on Batch Processing using Processing Framework. For loading multiple files, the key is In the Batch Processing dialog, the first tab is Parameters where we define out inputs. Click the ... next to the first row in the Input layer column. Browse to the directory containing the global transportation layers that you had downloaded. ...


1

I couldn't even reproduce the inconsistency in the heights between the .laz and the .asc files, as the .laz file opened in ENVI LiDAR is now showing elevation values consistent with what shown in QGIS with the .asc file (~25m for the white building above). As explained in this document UK Environment Agency LiDAR Data, both of these products are projected ...


1

To run laszip in a command prompt in Windows you need to use the "-i" paremeter to specify your input files: laszip -i lidar.laz or laszip -i *.laz To run the above commands Laszip must be in your PATH environment variable: set path=%path%;<path_to_your_laszip_exe> set path=%path%;C:\LAStools\bin And the laz files must be in your current ...


1

It seems you are running on windows. Simply double-click the laszip.exe program and operate it via the GUI. You can browse to the folder you want to decompress via the 'browse...' rollout on the left side of the menu. Why are you needing to decompress LAZ to LAS? Is there a software you want to use that does not support LAZ natively? Which one? Check this ...


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