12. The encoding method according to claim 11 , wherein said base code is formed by two sections of said code (4, 3, 2).
11. The encoding method according to claim 1 , wherein at least one of said local codes comprises a two-state code (4, 3, 2) setting up an association, with an input state bit, of an output state bit, as a function of four label bits, where: 4 is the length of said local code, or the number of the label bits of the local code; 3 is the size of said local code; 2 is the minimum distance from said base code.