1. A computer-implemented method for applying a filter to an image comprising: receiving a filter setting; selecting a selected filter from a family of filters stored on a computer-readable storage medium, based at least on the filter setting, wherein the family of filters comprises a plurality of filters each being an approximation of a function on different orders; determining parameters of the selected filter; and applying the selected filter to a stored image with a processor; wherein the family of filters comprise Gaussian blur filters and the filter setting comprises blur strength; wherein the Gaussian blur filter is an approximation of a Gaussian function represented by h a ⁡ ( k ) = ∑ i = 0 n ⁢ ⁢ a i ⁢ ⅇ - λ i ⁢ k σ ; wherein σ is a standard deviation value based at least on the blur strength, i is a filter order, a i and λ i are parameters; and wherein determining parameters of the Gaussian blur filter comprises calculating a i and λ i by minimizing a mean square error function of h a (k).