1. An adaptive filter for filtering noise from a low-light image, the adaptive filter comprising: a digital-signal processor configured for executing instructions, said instructions comprising: (i) a morphology filter for dilating edge pixels corresponding to an edge detected in the image, thereby dividing pixels in the image into non-edge pixels and dilated edge pixels; and (ii) a comparative filter for comparing a pixel in the non-edge region to a region surrounding the pixel and optionally replacing the pixel, based on a result of the comparison, with a new pixel derived at least in part from the region surrounding the pixel.