Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/GDB|GeoGateway+Data+Model">GeoGateway Data Model</a><hr>
<H4>Bitmap Masks (BIT)</H4>
A bitmap segment is a special raster layer with each pixel having either
the value of 0 or 1. They are normally used as masks for an area of operation,
for instance: training areas in classification.<p>
Bitmaps are rectangular raster grids, much like image layers, and must have
the same number of pixels and lines as any other raster layer in the
database. The georeferencing associated with the raster layers 
is also assumed to apply to bitmap layers.
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Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/GDB|GeoGateway+Data+Model">GeoGateway Data Model</a><br>
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