proj lib integration¶

PROJ is a generic coordinate transformation software that transforms geospatial coordinates from one coordinate reference system (CRS) to another. This includes cartographic projections as well as geodetic transformations. PROJ is used and utilized in LAStools (las2las) to transform LiDAR data between various coordinate reference systems and to retrieve detailed
represenations and information about CRS (lasinfo).

Key features include:

Transformation of point coordinates between different CRS.
Conversion and representation of CRS in various formats (EPSG, WKT, PROJ string, PROJJSON).
Retrieval of metadata such as ellipsoids, axes, and datum information related to a CRS.

The integration of the PROJ library provides a flexible and powerful means to perform geodetic transformations directly within LAStools.

The source code for the PROJ library is available at https://github.com/OSGeo/PROJ.

Installing the PROJ Library¶

To use the PROJ library in LAStools, it must be installed on your system (possibly via qigis or OSGeo4W). If the PROJ library is not already installed, here are several methods to install it:

Package Managers¶

Conda: Install PROJ with the following command:

conda install -c conda-forge proj

And for the PROJ data:

conda install -c conda-forge proj-data

Docker: Get the Docker image with:
```
docker pull osgeo/proj
```

QGIS/OSGeo4W Installation¶

By installing QGIS, you automatically get the PROJ library installed and configured.

Windows:

Download the QGIS installer from the [QGIS setup] (https://www.qgis.org/download/).
Run the installer and follow the installation steps.
Once QGIS is installed, the PROJ library will be available.

Or use the [OSGeo4W setup] (https://download.osgeo.org/osgeo4w/v2/) and select “proj” under “Commandline_Utilities”. The OSGeo4W installer allows you to install QGIS along with the PROJ library.
Linux: Debian/Ubuntu: QGIS can also be installed on Linux distributions, which will include the PROJ library.

Add the QGIS repository:

sudo add-apt-repository ppa:ubuntugis/ppa
sudo apt update

Install QGIS:

sudo apt install qgis qgis-plugin-grass

The PROJ library is now installed with QGIS.

Fedora::

sudo dnf install qgis qgis-grass

Further installation options¶

Linux: Debian/Ubuntu:

sudo apt-get install proj-bin

Fedora:

sudo dnf install proj

Red Hat:

sudo yum install proj

Mac OS X: Using Homebrew:

brew install proj

Or MacPorts:

sudo port install proj

Required Files for PROJ in LASTools¶

To ensure that the PROJ library functions correctly with LASTools, you need to have the following library files available:

proj
libcrypto
libcurl
libssl
sqlite3
tiff
zlib

Additionally, ensure that the PROJ data files, including the proj.db, are installed for full functionality.

File and Data Locations¶

file and data standart Directories: If LAStools uses the PROJ library, the files and data of the library are automatically searched for in the standard directories of the installation via Conda or QGIS/OSGeo4W.
Custom Directory: Alternatively, you can place the library files and PROJ data in custom directories of your choice. To use these custom directories, set the environment variables as follows:
```
set LASTOOLS_PROJ=...
```
for the PROJ library directory, and
```
set PROJ_LIB=...
```
for the PROJ data directory.

Important Note¶

Ensure that the version of the PROJ data matches the version of the PROJ library to avoid compatibility issues. For more information and detailed instructions about the installation, refer to the official PROJ installation page https://proj.org/install.html

License¶

This library is free to use.

PROJ is released under the X/MIT open source License. For more information about the license and usage of the PROJ library, refer to the official PROJ repository or the official website https://proj.org.

Support¶

To get more information about LAStools just goto the LAStools Google Group and enter the tool name in the search function. You will get plenty of samples to this tool.

To get further support see our rapidlasso service page

Check for latest updates at https://rapidlasso.de/category/blog/releases/

If you have any suggestions please let us (info@rapidlasso.de) know.