McInerney D., Kempeneers P. Open Source Geospatial Tools: Applications in Earth Observation

Springer, 2015. — 368 p.While there are many packages currently available that can be used for geospatial analysis, this work focuses on a specific subset of them. This is due either to their unique functionality that they provide or the fact that they underpin other software packages. For vector and raster data processing, they are:
GDAL/OGR
pktools
Orfeo Toolbox
In less detail, we also cover a number of packages that deal with three-dimensional point clouds obtained from LiDAR instruments. Rather than giving an exhaustive description, we provide a brief overview with some usage examples of the following packages:
liblas
PDAL
LAStools
PulseTools
SPDLib
A key motivating factor behind this undertaking is the capacity of the selected tools to provide highly effective capabilities for processing geospatial data. Another is the fact that while they continue to be developed at a rapid rate, the documentation and related training material associated with them are distributed on disparate websites such that the consolidation of the explanation of a particular tool and its command line options is deemed necessary. The tools that we cover in the book all have the following in common:
free and open-source;
ability to operate in batch mode (command line processing);
available on a Linux operating system and other systems.
These three requirements are described in more detail. First, free and open-source software has gained in popularity over the last decade. The terms free and open-source have been used in different contexts with different meanings. Without entering into the discussion, it is worth recalling the idea of the free software foundation (FSF), in the following terms: Free as in free speech, not as in free beer. The philosophical view of freedom is ethical and goes beyond the idea of open-source, which is rather focused on practical issues, such as making or having powerful, reliable software (Stallman 2009). Nevertheless, the two categories overlap. The unrestricted use of free software is particularly important for capacity building, in particular in developing countries. With the access to remote sensing data archives (Landsat, MODIS, Proba-V, and the upcoming Sentinel missions) becoming more open, both data and processing software are now available to a large community. This provides new opportunities for research in Earth system sciences and its related policy support.