Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/GDB|GeoGateway+Data+Model">GeoGateway Data Model</a><hr>
<H4>Segment Organization</H4>
Data other than raster imagery is often referred to as segment data, or
as auxiliary segments. This relates back to the structure of the PCIDSK 
file; however, you can consider segments as being similar to layers or
channels.<p>
Unlike raster channels, auxiliary segments are not required to be numbered 
sequentially. For instance, in the irvine.pix PCIDSK file there are two
PCT (PseudoColour Table) segments, numbered 7 and 8. In PCIDSK files the
segment number, for a particular segment, is unique among all other segments
in that PCIDSK file. This is not generally true in other formats; for
instance, a bitonal TIFF file might have a PCT segment with the number 1, 
and a bitmap segment number 1.<p>
Each type of segment has a three letter code associated with it. This 
three letter code is often included in reports and utility programs to 
show the type.
<P>
<UL>
<LI> VEC: Vectors
<LI> BIT: Bitmap (1 bit raster)
<LI> GCP: Ground Control Points
<LI> LUT: Lookup Table
<LI> PCT: PseudoColour Table
<LI> TEX: ASCII Text
</UL>
<hr>
Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/GDB|GeoGateway+Data+Model">GeoGateway Data Model</a><br>
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