<br><font size=2 face="sans-serif">Hi,</font>
<br>
<br><font size=2 face="sans-serif">I hope someone has some experience with
this:</font>
<br>
<br><font size=2 face="sans-serif">I am classifying pixel values from a
tiff file (converted from asc). The values are in range 0-100 and I need
to clasify them in a following manner (don't bother the COLOR values :-):</font>
<br>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] <=
35)</font>
<br><font size=2 face="sans-serif"> NAME '35dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
35 and [pixel] <=40)</font>
<br><font size=2 face="sans-serif"> NAME '40dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
40 and [pixel] <=45)</font>
<br><font size=2 face="sans-serif"> NAME '45dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
45 and [pixel] <=50)</font>
<br><font size=2 face="sans-serif"> NAME '50dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
50 and [pixel] <=55)</font>
<br><font size=2 face="sans-serif"> NAME '55dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
55 and [pixel] <=60)</font>
<br><font size=2 face="sans-serif"> NAME '60dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
60 and [pixel] <=65)</font>
<br><font size=2 face="sans-serif"> NAME '65dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
65 and [pixel] <=70)</font>
<br><font size=2 face="sans-serif"> NAME '70dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
70 and [pixel] <=75)</font>
<br><font size=2 face="sans-serif"> NAME '75dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
75 and [pixel] <=80)</font>
<br><font size=2 face="sans-serif"> NAME '80dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br><font size=2 face="sans-serif"> CLASS</font>
<br><font size=2 face="sans-serif"> EXPRESSION ([pixel] >
80)</font>
<br><font size=2 face="sans-serif"> NAME '>80dB(A)'</font>
<br><font size=2 face="sans-serif"> COLOR 255 255 255</font>
<br><font size=2 face="sans-serif"> TEMPLATE "void"</font>
<br><font size=2 face="sans-serif"> END # Class</font>
<br>
<br>
<br><font size=2 face="sans-serif">Since this can be slow, can I make some
performance improvements by using PROCESSING SCALE=min,max and SCALE_BUCKETS
parameters? I have tried something like:</font>
<br>
<br><font size=2 face="sans-serif">PROCESSING "SCALE=1,100"</font>
<br><font size=2 face="sans-serif">PROCESSING "SCALE_BUCKETS=20"</font>
<br>
<br><font size=2 face="sans-serif">but I didn't really see much difference.
Is this OK? Is it enough anyway to add those two statements and leave the
classes intact?</font>
<br>
<br><font size=2 face="sans-serif">thanks very much</font>
<br>
<br><font size=2 face="sans-serif">regards, dejan</font>