title: Extracting flat-field images from scene-based image sequences using phase correlation.
abstract: Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.
authors.affiliation: Research Support Instruments, 4325-B Forbes Boulevard, Lanham, Maryland 20706, USA.
authors.forename: James N
authors.initials: JN
authors.lastname: Caron
authors.affiliation: Naval Research Laboratory, Code 7231, 4555 Overlook Avenue, SW, Washington, DC 20375, USA.
authors.forename: Marcos J
authors.initials: MJ
authors.lastname: Montes
authors.affiliation: Naval Research Laboratory, Code 8231, 4555 Overlook Avenue, SW, Washington, DC 20375, USA.
authors.forename: Jerome L
authors.initials: JL
authors.lastname: Obermark