1. A method for recognition of an identifier, comprising: for each of a plurality of objects, storing a first visual signature, which has been extracted from at least a part of a respective first image of the object captured at a first location, the first visual signature comprising a multidimensional statistical representation of pixels of at least the part of the respective first image, and first information associated with the first captured image, the first information comprising a first time stamp; computing a measure of similarity between a second visual signature and at least some of the first visual signatures to identify a matching one of the first visual signatures, based on the computed measure of similarity, the second visual signature having been extracted from at least a part of a second image of a second object captured at a second location, based on at least a part of the second image, the second visual signature comprising a multidimensional statistical representation of pixels of at least the part of the second image; retrieving the stored first information associated with the matching one of the first visual signatures and stored second information associated with the second captured image, the second information comprises a second time stamp which is later in time than the first time stamp; performing a test which is a function of the retrieved stored first time stamp and the stored second time stamp; and recognizing an identifier of the second object based on a captured image of the second object, only when it is confirmed that the test has been met.