TargAn

The TargAn software package is dedicated to parameterizing backscatter image regions of interest (ROIs), derived by marine geo-acoustical instrumentation (e.g., Side Scan Sonars, Synthetic Aperture Sonars and Multi-Beam Echo-Sounders).

The ROIs, whose boundaries are marked out either manually or via simple segmentation techniques, are analyzed for as many as thirty-seven features. The adopted and developed methodologies lead to the extraction of:

1. intensity (1st order) and texture analysis statistics estimated from the inner ROI,
2. descriptives that measure the discreteness of the ROI in comparison to the intensity characteristics of the peripheral seabed,
3. shape geometry descriptives of the ROI’s boundary itself and
4. regional statistics of distinct (segmented) objects possibly included in the ROI.

TargAn is implemented in Matlab, with a graphical user interface (GUI) that helps the user have control over the digitization, segmentation and feature extraction processes involved. It also provides tools for the construction of compact geo-databases (georeferenced points, polygons and b/w images), suitable for geostatistical analysis and visualization in popular Geographical Information Systems, concerning the extracted descriptives and the geographic features (e.g., ROIs’ boundaries, skeletons, segmented objects) that have been considered for ROIs analyses.  The TargAn software has proven to be useful in the objective quantification of large amounts of image ROIs, a fact that has been demonstrated through case studies of geological and biological interest.