Abstract: A method of reducing an amount of fixed pattern noise from an image signal generated by an image sensor. The method includes, for each operational pixel in the image signal, applying a recursively updated offset term to generate a corrected image signal. The offset correction terms are recursively updated by spatially filtering the corrected image signal for a current frame of the image signal; comparing the filtered corrected image signal of the current frame with a spatially filtered corrected image signal of a preceding frame of the image signal; and updating the offset correction terms with terms generated as a function of the comparison.

Abstract: A method of reducing an amount of fixed pattern noise from an image signal generated by an image sensor. The method includes, for each operational pixel in the image signal, applying a recursively updated offset term to generate a corrected image signal. The offset correction terms are recursively updated by spatially filtering the corrected image signal for a current frame of the image signal; comparing the filtered corrected image signal of the current frame with a spatially filtered corrected image signal of a preceding frame of the image signal; and updating the offset correction terms with terms generated as a function of the comparison.

Abstract: An adaptive method for removing fixed pattern noise from focal plane array (FPA) imagery. A set of correction terms is applied to the focused image from the FPA, and a filter is applied to the corrected, focused image. The set of correction terms is also applied to a blurred version of the FPA image, and the filter is applied to the corrected, blurred image. Fixed pattern noise errors are then calculated using the filtered imagery, and employed to update the correction terms. The updated correction terms are then used for processing the next image. In one embodiment, the filter is an anti-median filter. In another embodiment, the filter is an anti-mean filter.