ImageGear .NET allows you to specify a Region of Interest (ROI) as follows:
- Specify rectangular ROI for nearly all image processing methods 
 - Specify arbitrary ROI for most image processing methods (i.e., ellipse, polygon, and freehand) 
 - Create 1-bit mask image for identifying which pixels to include/exclude from image processing algorithms 
 
See ImGearROI Class, ImGearROIMask Class, and ImGearROIRectangle Class for more information.