5. The method according to claim 4 , in which the extraction process comprises disabling an error correction code and reading the modified digital word.
5. The method according to claim 4 , in which the extraction process comprises disabling an error correction code and reading the modified digital word. 7. The method according to claim 5 , furthermore comprising enabling the error correction code and reading each modified digital word, this read operation supplying the values of the bits of each initial digital word.