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Vectorization
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polyline. The longer segments are not added to the polyline. This allows you, for
example, to trace on maps curved isolines that are crossed by coordinate lines; the
algorithm automatically stops on intersections of traced isoline with long straight line
of grid. .The algorithm traces raster lines with a widths less than the value of the
Max width
parameter. The
Max break
parameter sets the maximum length of
ignored raster segments break. The
Approximation
parameter sets the accuracy of
approximation of raster segments by vector polyline.
Outlines
This algorithm is used to approximate outlines of flooded areas by polylines. This
algorithm creates closed polylines, approximating the boundaries of raster objects.
The boundary polylines consist only of straight segments.
The figure shows the results of vectorization with
the
Outlines
algorithm only. The original raster
fragment is on the left; the right figure illustrates
the results of vectorization.
This algorithm is controlled by the following options of the
Options
tab:
The algorithm traces raster lines whose width is greater than the value of the
Min
width
parameter. To obtain outlines of all raster objects, you only need to choose
outlines with the
Max Width
parameter to 0.
The
Approximation
parameter sets the accuracy of raster segments approximated
by vector outlines.
Hatches
Selects the algorithm for hatch recognition. WiseImage Pro recognizes simple
raster hatches and creates AutoCAD blocks, consisting of segments. The simple
raster hatch is a set of parallel raster lines. The
Hatches
algorithm searches for
hatches only if the
Lines
algorithm is also on. The accepted angles of raster lines
forming raster hatches are used as additional parameters.
Text Areas
Selects the algorithm for text recognition. WiseImage Pro distinguishes areas on the
image with raster text strings and applies the additional parameters.
The setting up of raster text string search options and the OCR module is carried
out in the
Texts
tab of the same dialog box. The setting up procedure is described
later in this chapter.
None
- does not vectorize raster text. Areas, containing
raster text strings are ignored.
Text Areas
– creates rectangles bounding raster texts.
These areas are not vectorized. Vector texts can be
entered manually with the help of the review and correction
procedure of recognized texts described below in this