A method and apparatus for constructing spatial representations of referents is provided. The method and apparatus have application in any area where a spatial representation of a referent is required. Examples are image processing and machine vision. In image processing the "referents" are signal sources which are being viewed by an image processing sensor, eg CCD array. The image sources will be points in a scene, for example. Currently available image systems must be aware of the relative positions of the image sensors. In prior art image systems, this information is usually provided a priori. In the present invention, no a priori information on the arrangement of the image sensors is required. Instead, a geometrical representation of the referents is produced by obtaining signals from the referents and utilizing the signals in order to provide the geometrical representation. The geometrical representation is built up purely from the signals provided by the sensors themselves. The invention assumes that behavioral differences between signals for any two referents imply a distance between the referents, and this assumption is utilized in order to build up the geometrical representation of the referents.