IRS standard data products are offered with two processing levels - radiometrically corrected and system corrected. System corrected is the higher level, which includes the radiometric and geometric correction of the data.
During the radiometric correction, distortions arising due to the non-uniform response of the detectors and the failure of specific detector elements will be corrected. The results are stored as integer values with eight or ten bit resolution.
The geometric correction takes care of several system dependent geometric distortions. This includes earth rotation effects, sensor focal plane detector geometry, optical axis alignment with respect to the spacecraft attitude reference, multi-band and multi-array misregistration and altitude and attitude variations.
Geometric corrections are performed using a dynamic model representing the imaging geometry. By using this model, an image to ground mapping is achieved. The result is projected into a path oriented or north oriented output image space by employing the user specified map projection and a resampling method.