A method of encoding an initial digital signal in an encoded signal, where the initial digital signal includes a sequence of samples representing a multidimensional space, and each sample may be assigned at least one physical magnitude. The method may include, for at least some of the current samples, locally encoding the signal in encoded local digital signals, with the encodings being performed in local reference frames each including the current sample considered and two reference samples. The reference samples may be chosen based upon a minimum gradient of the at least one physical magnitude, from among the available samples of the sequence, and the encoded signal may include the encoded local digital signals.