Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/ISOCLUS">ISOCLUS</a><hr>
<H3>PARAMETERS</H3>
ISOCLUS is controlled by the following global parameters:
<P>
<pre>Name     Prompt                                  Count     Type
FILE     Database File Name                      1-64      Char
DBIC     Database Input Channel List             1-16      Int
DBOC     Clustering Result Output Channel        0-1       Int
MASK     Area Mask (Window or Bitmap)            0-4       Int
NUMCLUS  Number of Clusters Desired              1         Int
MAXCLUS  Maximum No. of Clusters                 0-1       Int
MINCLUS  Minimum No. of Clusters                 0-1       Int
SEEDFILE Text File for Initial Seeds             0-64      Char
MAXITER  Maximum Number of Iterations            0-1       Int
MOVETHRS Movement Threshold                      0-1       Real
SIGGEN   Generate Signatures: YES/NO             0-4       Char
SAMPRM   Minimum Sample Threshold                0-1       Int
STDV     Standard Deviation                      1         Real
LUMP     Lumping Parameter                       0-1       Real
MAXPAIR  Maximum No. of Lumping Pairs            0-1       Int
BACKVAL  Background Grey level Value             0-1       Int
NSAM     Number of image points used in the samp ing       0-1
REPORT   Report Mode: TERM/OFF/filename          0-64      Char
</pre>
<H4>FILE</H4>
Specifies the name of the PCIDSK image file for which clustering
will be performed.
<P>
<PRE>
 EASI&gt;FILE=&quot;filespec&quot;
</PRE>
<H4>DBIC</H4>
Specifies the input channels to be used. These can be 8 bit, 16 bit,
or 32 bit real mixed in any way. Up to 16 input channels can be
specified.
<P>
<PRE>
 EASI&gt;DBIC=i,j,k,l,...
</PRE>
<UL>
<LI> Ranges of channels can be specified with negative values. For
example: {1,-4,10} is internally expanded to {1,2,3,4,10}. 
<LI> Duplicate channels are NOT allowed. 
</UL>
<H4>DBOC</H4>
Specifies the output channel for the clustering results. If no value
is specified, results will not be saved into a channel. For
signature generation, DBOC must be specified.
<P>
<PRE>
 EASI&gt;DBOC=i
 EASI&gt;DBOC=
</PRE>
DBOC can be equal to DBIC. Only the area under MASK is written to
DBOC.
<P>
<H4>MASK</H4>
Specifies the area in the input channel which should be processed.
This can be any one of the following:
<P>
<PRE>
 EASI&gt;MASK=xoff,yoff,xsize,ysize        | process window
 EASI&gt;MASK=                             | process entire channel
 EASI&gt;MASK=b                            | process only under bitmap
                                        | stored in segment b
</PRE>
<H4>NSAM</H4>
Specifies the number of samples to collect on which to perform the
the iterative clustering. This defaults to 262144 if not provided by
the user. If the indicated number is large than the total number of
pixels in the image then all the pixels in the image will be used.<p>
The time to compute each iteration is proportional to the number of
samples used, so using a lot more than the default number of samples
can make the clustering process much slower. Also, all the samples
are stored in memory, so a large NSAM value can lead to requirements
for a lot of memory. With 262144 samples, and five bands of 8-bit
input data the program would require approximately 1.3MB of memory
while with NSAM set to 2000000, it would take 10MB.
<P>
<PRE>
 EASI&gt;NSAM=             | Default to the normal 262144 samples
 EASI&gt;NSAM=1500000      | Use up to 1500000 sample pixels
</PRE>
<H4>REPORT</H4>
Specifies the file to which the generated report should be appended.
<P>
<PRE>
 EASI&gt;REPORT=&quot;filename&quot;
 EASI&gt;REPORT=           | defaults to terminal output
</PRE>
The following names have special meaning:
<P>
<PRE>
 EASI&gt;REPORT=&quot;TERM&quot;     | generates reports on your terminal
 EASI&gt;REPORT=&quot;DISK&quot;     | generates reports on file &quot;IMPRPT.LST&quot;
 EASI&gt;REPORT=&quot;OFF&quot;      | will switch off report generation
</PRE>
<H4>NUMCLUS</H4>
<PRE>
  Valid Values:   1 &lt;= x &lt;= 32
  Default:        16
</PRE>
Specifies the number of clusters (classes) desired. It should be
noted that this is only an estimate. The final number of clusters
may vary. However, the user can limit the variation by setting the
parameters MAXCLUS and MINCLUS. Since cluster 256 is reserved for
clusters discarded during clustering, the range of NUMCLUS is 0 &lt;
NUMCLUS &lt; 256.
<P>
<PRE>
 EASI&gt;NUMCLUS=x
 EASI&gt;NUMCLUS=          | defaults to 16
</PRE>
<H4>MAXCLUS</H4>
<PRE>
  Valid Values:   1 &lt;= x &lt;= 32
  Default:        16
</PRE>
Specifies the maximum number of clusters allowed. This parameter
limits the total number of clusters allowed during splitting.
<P>
<PRE>
 EASI&gt;MAXCLUS=x
 EASI&gt;MAXCLUS=          | defaults to 16
</PRE>
<H4>MINCLUS</H4>
<PRE>
  Valid Values:   1 &lt;= x &lt;= 32
  Default:        16
</PRE>
Specifies the minimum number of clusters allowed. This parameter
limits the number of clusters allowed during Lumping.
<P>
<PRE>
 EASI&gt;MINCLUS=x
 EASI&gt;MINCLUS=          | defaults to 16
</PRE>
<H4>SEEDFILE</H4>
<PRE>
  Valid Values:   &lt;filename, max. 64 characters&gt;
  Default:        &lt;none&gt;
</PRE>
Specifies the text file name to read in initial seeds. If no
filename is given, seeds will be generated diagonally along the
n-dimensional histogram.
<P>
<PRE>
 EASI&gt;SEEDFILE=&quot;filename&quot;
</PRE>
To specify the seeds for 4 channels and 6 clusters in a text file,
you can follow the format as follows:
<P>
<PRE>
    1   1   1   1            | 1st seed position in channel 1,2,3,4
    5   3   5   9            | 2nd seed position in channel 1,2,3,4
   40  43  20  10            | 3rd seed position in channel 1,2,3,4
  100 101 140  50            | 4th seed position in channel 1,2,3,4
  150 155 200 175            | 5th seed position in channel 1,2,3,4
  240 200 195 140            | 6th seed position in channel 1,2,3,4
</PRE>
<H4>MAXITER</H4>
<PRE>
  Valid Values:   1 &lt;= x &lt;= 20
  Default:        20
</PRE>
Specifies the total number of iterations in calculating the cluster
mean positions.
<P>
<PRE>
 EASI&gt;MAXITER=x
 EASI&gt;MAXITER=          | defaults to 20
</PRE>
<H4>MOVETHRS</H4>
<PRE>
  Valid Values:   0.0 &lt;= x &lt;= 1.0
  Default:        0.01
</PRE>
Specifies the movement threshold in percentage of cluster means.
<P>
<PRE>
 EASI&gt;MOVETHRS=x
 EASI&gt;MOVETHRS=         | defaults to 0.01
</PRE>
If the movement of all cluster means is less than MOVETHRS , the
program has converged. For example, for all cluster means, the
following situation terminates the program:
<P>
<PRE>
  New cluster mean position - Old cluster mean position
  ----------------------------------------------------- &lt; MOVETHRS
              Old cluster mean position
</PRE>
<H4>SIGGEN</H4>
<PRE>
  Valid Values:   YES,NO
  Default:        NO
</PRE>
Specifies whether the signature for each cluster will be generated.
The user can utilize the signatures as inputs for the MLC (Maximum
Likelihood Classification) program to class other images.
<P>
<PRE>
  YES     generate signatures
  NO      no signature generated
</PRE>
DBOC must be specified if SIGGEN is YES.
<P>
<H4>SAMPRM</H4>
<PRE>
  Valid Values:   0 &lt;= x &lt;= 255
  Default:        5
</PRE>
Specifies the minimum sample threshold. The number of samples in a
cluster domain is compared to SAMPRM in the following way:
<P>
<PRE>
 EASI&gt;SAMPRM=x
 EASI&gt;SAMPRM=           | defaults to 5
</PRE>
When the number of samples in a cluster is less than SAMPRM, the
cluster will be discarded and the total number of clusters will be
reduced by 1.<p>
For a cluster,
<P>
<UL>
<LI> if the standard deviation is greater than STDV, and 
<LI> if the average distance of samples from the cluster center is
greater than the overall average distance of the samples from
their respective cluster centers, and 
<LI> if the total number of clusters is less than MAXCLUS, and 
<LI> if the number of samples in the cluster is greater than 2(SAMPRM
+ 1), or 
<LI> the number of clusters is less than or equal to NUMCLUS / 2, 
</UL>
then splitting of the cluster will occur.
<P>
<H4>STDV</H4>
<PRE>
  Valid Values:   x &gt;= 0.0
  Default:        10.0
</PRE>
Specifies the standard deviation. If a cluster has a standard
deviation greater than STDV, splitting may occur. A STDV value of
10.0 is reasonable.
<P>
<PRE>
 EASI&gt;STDV=x
 EASI&gt;STDV=             | defaults to 10.0
</PRE>
<H4>LUMP</H4>
<PRE>
  Valid Values:   x &gt;= 0.0
  Default:        1.0
</PRE>
Specifies the lumping parameter which is used in the following way:<p>
If the distance between two cluster centers is less than LUMP, the
total number of clusters is greater than MINCLUS, and the number of
Lumped pairs is less than MAXPAIR, then lumping of clusters will
occur.
<P>
<PRE>
 EASI&gt;LUMP=x
 EASI&gt;LUMP=             | defaults to 1.0
</PRE>
<H4>MAXPAIR</H4>
<PRE>
  Valid Values:   0 &lt;= x &lt;= 255
  Default:        5
</PRE>
Specifies the maximum number of pairs of cluster centres which can
be lumped during each iteration.
<P>
<PRE>
 EASI&gt;MAXPAIR=x
 EASI&gt;MAXPAIR=          | defaults to 5
</PRE>
<H4>BACKVAL</H4>
<PRE>
  Valid Values:   &lt;any integer, positive or negative&gt;
  Default:        &lt;none&gt;
</PRE>
Optionally specifies a background grey level value to be ignored
during classification. If this parameter is specified, pixels with
the background grey level value will be assigned class 0 (null
class).
<P>
<PRE>
 EASI&gt;BACKVAL=i
</PRE>
<hr>
Parent Topic: <A href="http://www.pcigeomatics.com/cgi-bin/pcihlp/ISOCLUS">ISOCLUS</a><br>
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