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<H4>TABLE LENGTH</H4>
In their paper, Narendra and Goldberg reported that for 6-bit
4-channel LANDSAT image data, there were about 6000 unique 4-D
histogram vectors (about 2^12.5) out of a total of 16777216 (2^24)
possible vectors. Therefore, it seemed reasonable to assume that for
8-bit 4-channel image data, there would be about 96000 (2^16.5) out
of a total of 2^32 possible vectors. Hence, the belief that a hash
table of length 99991 is sufficient.<p>
Dr. Goldberg stated that he used a maximum table length of 19993 in
his program GTC (Graph Theoretic Classifier). He said that
clustering on 8-bit resolution data is not meaningful, because of
undersampling, the need for smoothing, and the large number of
erroneous peaks in the histogram.
<P>
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