z Image includes geometric distortions
– Internal distortions
– External distortions
z Geometric correction is
– To remove internal distortions
– To remove external distortions
– To identify the location of each pixels on the earth
z Overlay with map and other images
– To convert coordinate system ( such as lat-lon -> UTM )
z Parameter determination
– Systematic
– Non-Systematic ( Black box type )
– Combined