this example as a Mathematica notebook.
Image Processing defines a large number of specialized functions
in order to increase your productivity in performing many common image analysis operations.
It is sometimes of interest to process a single subregion of an image,
leaving other regions unchanged. This is commonly referred to as region-of-interest (ROI)
processing. Image subregions may be specified conveniently by using Mathematica
graphics primitives such as Point, Line, Circle, or Polygon
or simply by listing vertex positions. Here are two demonstrations.
Read in an image and display it.
Define a region of interest. See the
for more information on interactively selecting coordinates.
Display the region of interest.
This shows the result of applying a Sobel edge detector to the region defined by roi.
As a second example, consider the application of a threshold operator to an
irregular region of interest. The vertices were selected using the point-and-click method
as described earlier.
This shows the region of interest.
This shows the result of applying the threshold operator to the region of interest.