1. A method for converting a binary image signal having a first resolution to a gray image signal having a desired resolution, comprising the steps of: (a) receiving the binary image signal having the first resolution; (b) electronically simulating, using the received binary image signal, a printing process using a function resembling a Gaussian function to generate a first continuous gray image signal from the received binary image signal; (c) sampling the first continuous gray image signal at a second resolution to produce a sampled gray image signal, the second resolution being higher than the first resolution; (d) filtering the sampled gray image signal to produce a bandlimited gray image signal; (e) linearly interpolating the bandlimited gray image signal to produce a second continuous gray image signal; and (f) sampling the second continuous gray image signal at a certain frequency, thereby producing a gray image signal having the desired resolution.