Shorelines subset extraction:
In many applications, shorelines (or any other limits) need to be organized as closed polygons. The shorelines extractor program aims to extract a sub-set of the original shorelines data set in a given frame and adding border lines necessary to maintain the closure of the extracted limits. The final subset is composed of closed polygons fitting the region of extraction.
Closed polygons extraction example (South Korea shorelines)
GSHHS full resolution shorelines (gray lines), extracting frame (green lines), final shorelines (red lines)
Controlling shorelines resolution:
The shorelines filtering software aims to control the level of details in a given shorelines data set. Simple data set decimation (elimination of over-densified points with respect to an arbitrary resolution) can lead to quite poor results. The shorelines filtering program allows to truly control the level of details by smoothing shorelines and possibly aggregating close islands clusters. Again, the resulting filtered shorelines is composed of closed polygons.
It can be extremely useful in numerical modeling grid semi-automized construction (shorelines sampling for unstructured meshes, land mask determination for structured grids, etc...).
Shorelines filtering example (South Korea shorelines)
GSHHS full resolution shorelines (gray lines, ~100m best resolution), final shorelines (red lines, 2 km true resolution)