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Vectorization
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The vectorization process is directly influenced by the setting of the geometrical
parameters of recognition, which are located in the
Options
tab of this dialog box.
Points
This algorithm is intended for recognizing elevations marks on geodesic plans and
similar images.
WiseImage will recognize a raster point with a size not less than 2x2 pixels (objects
smaller than this are considered as speckle and ignored), and which maximum
vertical and horizontal extents are not greater than
Max Width
value.
A point-object can be only recognized in automatic mode.
Do not switch this mode on when recognizing images of poor quality or images
containing many speckles, since speckles cam be recognized as points.
Lines
Turns on the algorithm for line recognition. As a result of this algorithm LINE entities
are created.
The figure shows vectorization results when
only the
Lines
algorithm is on. The original
raster fragment is shown on the left; the
figure on the right represents the
vectorization results when the objects width
display option is off.
There are the following additional parameters:
Arrows
If this option is on, then WiseImage searches for raster analogues
of dimension lines (lines with one or two arrows at the end points)
and, if the arrows are found, creates appropriate AutoCAD
dimension objects (DIMENSION).
Line Types
If this option is on, then WiseImage recognizes dashed and dash-
dotted straight lines, creating vector lines with the corresponding
line type.
This algorithm is influenced by the following options of the
Parameters
tab:
It recognizes raster objects with lengths greater than the value of the
Min length
parameter and with widths less than the value of the
Max width
parameter.
The
Max break
parameter sets the maximum length of the ignored raster line break.
The
Approximation
parameter sets the accuracy of raster lines approximated by
vector objects. If the raster quality is poor, then you need to reduce this parameter
so that the algorithm can recognize raster objects with significant form distortions.
If the
Orthogonalization
option is on, then recognized segments are aligned both
parallel and perpendicular to the direction specified in the
Base angle
field. The
segments with small angles of deviation from the appropriate directions are aligned.
The accepted deviation value, for which orthogonalization is performed, is