A bivariate fractal interpolation surface with an individual vertical scaling factor

In this paper, a lemma, and two theorems for a bivariate fractal interpolation surface (BFIS) generated by an iterated function system (IFS) with an individual vertical scaling factor, are provided. Further, as a demonstration for the effect of the individual vertical scaling factor which characterizes the BFIS, the examples of higher resolution reconstructions from low resolution images are illustrated.