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Region-of-Interest Processing

It is sometimes of interest to process a single sub-region of an image leaving other regions unchanged. This is commonly referred to as region-ot-interest (ROI) processing. Here we show an example of edge detection in a rectangular ROI using a real image. This loads the example image.


Here we define a region-of-interest. Image regions may be conveniently selected using the mouse and keyboard. To select a particular region, click the displayed graphics object. In Windows (for other systems consult Input/Get Graphics Coordinates ), press the [Ctrl] key and click a point of interest. The point will be selected. This may be repeated for as many points as desired. Use the Copy and Paste command to paste the recorded list of positions to any cell or expression in the notebook.


This shows the result of applying a Sobel edge detector to the region defined by roi.



Further reading

User's Guide: Sections  5.6, 7.3.

Function Index: ImageRead, EdgeMagnitude, RegionProcessing, SobelFilter.