1. A personal identity verification process for evaluating authenticity of an input facial image against a class of different training images representing the face of an individual, the process including processing image data representing the input facial image to generate a first error correcting output code (ECOC) classifier output vector, processing image data representing the different training images of said class to generate a set of second ECOC classifier output vectors, comparing said first ECOC classifier output vector with said set of second ECOC classifier output vectors, and evaluating authenticity of said input facial image with respect to said class of training images in dependence on the comparison.