The Airborne Lidar Processing System (ALPS) was used to process data acquired by the EAARL-A and EAARL-B lidar systems. The EAARL sensors were operational between 2001 and 2014. The USGS has no plans for further development or support of EAARL or of its associated software (including this software).
The main ALPS software runs under a combination of Yorick and Tcl/Tk. The software also leverages a number of third-party software packages. Additionally, ALPS also includes a collection of stand-alone scripts and compiled utility programs that are used for tasks outside of the main program.
The install directory can be used to install the various software that ALPS requires to run. The software is expected to be installed alongside of this code repository. For example, if you want to install the software under /opt/alps, then you would put this repository at /opt/alps/lidar-processing.
To build the software, create a directory named build alongside of the repository. For example, if the repository is at /opt/alps/lidar-processing, then the build directory should be located at /opt/alps/build. Then cmake is used to generate the build files. Then you can download the software and install it. Using the example installation location of /opt/alps, here are the commands to run:
cd /opt/alps
mkdir build
cd build
cmake ../lidar-processing/install
make download
make install
Please be advised that you may also have to install additional development libraries using the package manager (such as apt-get or yum) provided by your linux distrution.
The idl subdirectory contains code that runs in the IDL programming language. IDL requires a paid license and must be installed separately from ALPS if you intend to use the small portions of the software that require it.
ALPS also contains some experimental python integration code. However, Python and its required packages are not installed as part of the installer process.
By default, the installer code will download the source code for each required package. However, it also supports using a directory of predownloaded files. It will check for a directory named sources alongside of the build and lidar-processing directories. For example, if you are installing under /opt/alps, then it will look for /opt/alps/sources.
If the sources directory exists, then the "make download" step will extract files from that directory instead of downloading from the internet.
You can generate a sources directory by following the following steps:
cd /opt/alps
mkdir build
cd build
cmake ../lidar-processing/install
make download
make archive
The final command will archive the downloaded sources into the sources directory.
This software is licensed under CC0 1.0 and is in the public domain because it contains materials that originally came from the U.S. Geological Survey (USGS), an agency of the United States Department of Interior. For more information, see the official USGS copyright policy.
This software is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The software has not received final approval by the U.S. Geological Survey (USGS). No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. The software is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the software.
The USGS provides no warranty, expressed or implied, as to the correctness of the furnished software or the suitability for any purpose. The software has been tested, but as with any complex software, there could be undetected errors. Users who find errors are requested to report them to the USGS.
References to non-USGS products, trade names, and (or) services are provided for information purposes only and do not constitute endorsement or warranty, express or implied, by the USGS, U.S. Department of Interior, or U.S. Government, as to their suitability, content, usefulness, functioning, completeness, or accuracy.
Although this program has been used by the USGS, no warranty, expressed or implied, is made by the USGS or the United States Government as to the accuracy and functioning of the program and related program material nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith.
This software is provided "AS IS."