The “Flier finder” algorithm is dedicated to one of the major identified problem:
the quite common presence of anomalous data in the finalized gridded bathymetry
to the hydrographic branches (aka “fliers”). This represents a major concern since,
when fliers are found, there is considerable time and effort required to remove
as it involves re-computation and re-finalization of the grids,
which can take several days (or longer) to accomplish with the additional
that the output is no longer the authentic field submission. This algorithm
to detect fliers as early as possible in the quality control process.
Its initial implementation scans gridded bathymetry and flags abrupt depth changes
as per user-set criteria, as shown in figure (white “lassos” encircle the anomalous
Several algorithm modifications have also been testing (e.g., by including the
of additional statistic layers provided by a CUBE DTM).
The “VALSOU to grid check” and “feature scan” algorithms have their focus on the
between gridded bathymetry and submitted feature files, as well as
the adherence of those feature files to current specifications.
Wrecks, rocks, and obstructions should have appropriate representation in the
with regards to position and least depth. It is a common situation at HBs to receive
with hundreds (or even thousands) of features that need to be manually checked
against the grid
to ensure agreement, and also to ensure proper attribution.
This process can be a massive time sink and, having a monotonous nature,
makes it perfectly suited for automation. The developed algorithms scan the gridded
and feature files to ensure this agreement, and that the attributes of the feature
per current version of the NOAA Hydrographic Survey Specifications and Deliverables
(HSSD) manual (QC Tools),
or the current NOAA HCell Specifications (depending on which phase of the
that the survey is in) (HCellScan tool). An example of the agreement we wish to
observe is shown