Abstract: The statistical tools used to compare images are often based on multivariate statistics and use images as observations. This approach does not take into account the spatial and dependence structures in the images. Here we follow another approach in the sense that the number of pixels in the images is the number of observations. We also take into account spatial and dependence structures by modelling images with Gibbs random fields with nearest-neighbors interactions. The idea of the proposed method of comparison of images is to model the images by Gibbs random fields with a finite number of parameters and to test equality of parameters between the pooled images of each group. We obtain a test statistic that is easy to calculate, and the limiting distribution of the statistic is a chi-square distribution. Applications to handwrittens signatures and pattern recognition are presented.