ImageGear for C and C++ on Linux v18.8 - Updated
Image Correction
User Guide > How to Work with... > Image Processing and Cleanup > Image Correction

ImageGear provides several functions whose specific purpose is to correct an image's appearance. The functions in this group include:

IG_IP_despeckle() Removes noise from a 1-bit image, using a 3x3 median filter on the image.
IG_IP_median() Uses a median filter to reduce noise in 8-bit gray level and 24-bit images.
IG_IP_deskew_auto() De-skews a 1-bit image that was created by reading a text file. You can specify a threshold angle below which de-skewing should not be performed.
IG_IP_deskew_angle_find() Will analyze a 1-bit image and report to you the angle at which it is skewed.


In general, you would use the image correction functions with images that have been obtained by scanning text documents or graphical images.