1. An imaging device comprising: an image sensor comprising an array of pixels; a processor coupled with the image sensor; and a mask coupled with the image sensor, the mask configured to darken a plurality of isolated pixels or groups of pixels interspersed within the array of pixels; wherein the array of pixels comprises a plurality of un-darkened pixels, and the processor is configured to: receive image data from the image sensor including a signal for each pixel in the array of pixels, and determine a dark current fixed pattern noise based on the image data received from the plurality of darkened pixels or groups of pixels; for each of the plurality of un-darkened pixels in the array of pixels, determine nearby darkened pixels that are nearest to each of the plurality of un-darkened pixels; determine a change in a dark current fixed pattern of each of the nearby darkened pixels from a previously recorded dark current fixed pattern of each of the nearby darkened pixels; determine a change in a dark current fixed pattern for each of the plurality of un-darkened pixels from a previously recorded dark current fixed pattern of each of the plurality of un-darkened pixels, based on an interpolation of the change in the dark current fixed pattern of each of the nearby darkened pixels that are nearest to each of the plurality of un-darkened pixels; determine a dark current fixed pattern of each of the plurality of un-darkened pixels based on the change in a dark current fixed pattern for each of the plurality of un-darkened pixels; and subtract the dark current fixed pattern of each of the plurality of un-darkened pixels from the signal for each of the plurality of un-darkened pixels.