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  Engauge Digitizer - Point Match Requirements</H2>
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<H3>Separation of Points</H3>
<P>Engauge is limited in terms of types of point graphs that can be
automatically digitized in <A HREF="tutorautopointgraph.html">point graph mode</A>.</P>
<P>The point graph on the left below may be automatically digitized by Engauge, because
each point is easily distinguished from its closest neighbors. Engauge will recognize
the 22 points.</P>
<P>The point graph on the right below cannot be automatically digitized by Engauge, 
because every point is connected to its neighbors. Even worse, some points are overlapping.
In this case, Engauge will not be able to distinguish each curve point its neighbors, and
from the curve line.</P>
<IMG SRC="pointmatchrequirements.png" ALIGN=MIDDLE ALT="Good graph points are separated">
<P>Your point graph should look more like the left figure if you wish to use
point graph mode.</P>
<H3>Image Size</H3>
<P>Point Matching involves a lot of mathematical calculations, and a lot of computer
memory, especially for larger images.</P>
<P>Engauge can easily handle a 2000x2000 pixel image, on a 512 megabyte Linux system. 
However, larger images and reduced memory may cause problems.</P>
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