Spontaneous emission of fluorophores located close to a reflecting surface is modified by the interference between direct and reflected waves. The spectral patterns of fluorescent emission near reflecting surfaces can be precisely described with a classical model that considers the relative intensity and polarization state of direct and reflected waves depending on dipole orientation. An algorithm based on the emission model and polynomial fitting built into a software application can be used for fast and efficient analysis of self-interference spectra, yielding information about the location of the emitters with subnanometer precision. Spectral information was used to study thin films of fluorescent substances on surfaces.