1. A method of filtering a digital image of a physical scene using an approximated bilateral filter, the method comprising: adding a bilateral correction term to a first value of a signal at a point to produce a filtered signal value, the bilateral correction term being a product of a summation term and an approximation of a normalization factor of an exact bilateral filter, wherein the summation term comprises a summation of products of a convolution kernel coefficient, a photometric weight, and a difference between the first value of the signal and a second value of the signal at a neighboring point, wherein the signal represents the digital image, and wherein adding a bilateral correction term is performed in a bilateral filter system; and outputting the filtered signal value representing a filtered digital image, the outputted filtered signal value being one or both of stored in memory and displayed for viewing by a user.