View/Open - ARAN

The start of this study contains a glossary of terms, which are probably familiar to
most readers, and the next three chapters will refer to some terms which are
specific to this type of analysis. The first term is aerial imagery which is a
reference to all the spectral data obtained during the study. When described as
aerial imagery or raster polygons the reference is to an aerial image corrected to
allow for distortions such as slopes so that it corresponds to the vector mapping.
The second term which is repeated is the vector data, which refers to ordnance
survey data which was captured through a mix of photogrammetry and field
surveying. Although most readers are probably familiar with the .tiff file format it
is probably worth noting that the input photography files for the study are in the
GeoTIFF format. This format complies with the TIFF 6.0 standard and gives the
input data the flexibility to be accessed in a wide range of programs; which
allowed the imagery to be viewed outside the study software as the work was
undertaken. The key metadata components of this file format for this study are the
georeferencing coordinates which allow the sections being analyzed to be
accessed. This format is also recognized by the GDAL library being used in the
study. The projection used in all the files used in the study is ITM. This is not vital
to the success of the algorithm but making use of an additional projection requires
the inclusion of a transform function whenever the datasets intersect. The
following three chapters form chronological record of the study; starting with the
suggested algorithm (Chapter 2), followed by the sampling section necessary for
the basis of the procedure (Chapter 3) and finishing with a test on known polygons
for specific search values (Chapter 4).
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