Radiometrically-calibrated scene-based nonuniformity correction for infrared array sensors

This paper describes how a limited form of black-body-based calibration can be integrated into a recently developed algebraic scene-based algorithm for nonuniformity correction (NUC) in focal-plane arrays. The result of this integration is a scene-based NUC algorithm that is radiometrically accurate. By calibrating only those detectors that are on the array perimeter and relying on the scene-based algorithm to calibrate the interior detectors, using the perimeter detectors as a reference, radiometric accuracy can be achieved without disturbing the functionality of interior array elements. What makes this possible is the fact that the scene-based NUC algorithm used here is algebraic in nature and does not rely on any statistical assumptions on the scene irradiance in the image sequence. The algorithm utilizes knowledge of inter-frame motion to "lock" the biases of the interior array elements to those on the boundary. Notably, this can be achieved regardless of the spatial diversity in the scene and with, typically, a minimal number of frames in an image sequence. The performance of the technique is demonstrated using real infrared data.