We present a possibility to model morphology of surfaces of nanostructured semiconductor films by use of methods of nonlinear physics. We also describe experimental photoluminescence and absorption spectra in nanostructured fractal medium. By use of our theory we describe the new experimental fact of light localization in non-crystalline films. We suggest a fractal model for energy spectra of excitons in nanostructured semiconductors with porous structure. We obtain equations for exciton and multi-exciton energy depending on energy of exciting photon.