ImageGear for C and C++ on Windows v19.9 - Updated
Area Detection and Processing
User Guide > How to Work with... > Image Processing and Cleanup > Area Detection and Processing

Area detection functions allow you to detect an area in the image, using a predefined or custom pixel checking method.

See also the Red-Eye Removal group.

IG_IP_detect_area() Detects an area of pixels using a user-defined pixel checker.
IG_IP_detect_area_with_threshold() Detects an area of pixels using a specified threshold.
IG_IP_process_area Processes all pixels in the ROI area using a specified pixel processor.