11. The computer program product according to claim 7 , further comprising: computer code for generating likelihoods of sequences of speech segments by a Hidden Markov Model representing phonemes of speech; and computer code for recognizing at least one spoken word by means of the at least one codebook and the generated likelihoods.
11. The computer program product according to claim 7 , further comprising: computer code for generating likelihoods of sequences of speech segments by a Hidden Markov Model representing phonemes of speech; and computer code for recognizing at least one spoken word by means of the at least one codebook and the generated likelihoods. 12. The computer program product according to claim 11 , wherein the computer code for determining whether the speech signal corresponds to the utterance of a native speaker or to the utterance of a non-native speaker comprises: computer code for automatically classifying the speech signal as a signal corresponding to an utterance by a native or a non-native speaker.