1. A method for image processing, comprising: receiving, at an image processor, an input datacube created from a scan of a scene and from which an input scene image is derived, wherein the input datacube is a three dimensional set of measurements at a plurality of cross-scan locations (x's), along-scan locations (y's), and wavelength values (w's); transforming, at the image processor, the input datacube into a residual datacube by projecting out one or more basis vectors from each spatial pixel in the input datacube, the residual datacube being used to derive a three dimensional (3D) residual image, wherein each spatial pixel specifies a cross-scan location (x), an along-scan location (y), and contains measurements at a plurality of wavelengths (w's) in the input scene image; for each of a plurality of focal plane pixels in a focal plane used to scan the scene, identifying samples of the 3D residual image contributed by a subject focal plane pixel, wherein the samples are generated at a plurality of along-scan locations (y's) for a specific cross-scan location (x) and a specific wavelength (w) as the subject focal plane pixel is scanned along the scene; determining, at the image processor, a statistical parameter value for the identified samples of each focal plane pixel, the determined statistical parameter value encompassing the plurality of along-scan locations (y's) for the specific cross-scan location (x) and the specific wavelength (w); identifying, at the image processor, anomalous focal plane pixels based upon a comparison of the determined statistical parameter value of each focal plane pixel in the 3D residual image with the respective determined statistical parameter values of remaining focal plane pixels; comparing, at the image processor, residual values at the specific cross-scan location (x) and the specific wavelength (w) for each scanned sample of the identified anomalous focal plane pixels with values of corresponding scanned samples in the input datacube; determining, at the image processor, an estimation of at least one of a gain correction value and an offset correction value for the anomalous focal plane pixels based upon the comparing; and reconstructing, at the image processor, the input datacube based upon the estimation of at least one of the gain correction value and the offset correction value.