Additional information regarding a fingerprint is estimated, with a given level of confidence, on the basis of characteristics of a set of minutiae corresponding to this print. Local descriptors are determined around some at least of the minutiae, so that they comprise, in relation to zones comprising additional information estimated with the given confidence level, values calculated on the basis of said information and, in relation to zones not comprising such information, erasures. The local descriptors determined are quantized according to a given number of integer values, a value being reserved for erasures. The quantized local descriptors are coded with the aid of an error-tolerant coding algorithm associated with a decoding algorithm devised to take account of errors and erasures. And a pseudo-identity is determined on the basis of some at least of the coded quantized local descriptors.