30. The system of claim 29 , wherein the one or more programs further include instructions for: decomposing at least one spectral signature of an input speech signal into at least one content-independent characteristic unit; comparing the at least one content-independent characteristic unit to at least one of the content-independent recognition distribution values; and determining that the input speech signal is associated with the user if the at least one content-independent characteristic unit is within a threshold limit of the at least one of the content-independent recognition distribution values.
29. A system for speaker identification, comprising: one or more processors; memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for: receiving a plurality of different spoken utterances from a user; for each of the plurality of different spoken utterances: generating a respective phoneme-independent representation from the spoken utterance, the respective phoneme-independent representation including a respective spectral signature for each of a plurality of frames sampled from the spoken utterance; and decomposing the respective phoneme-independent representation to obtain a respective content-independent recognition unit for the user; calculating a content-independent recognition distribution value for the user based on the respective content-independent recognition units generated from the plurality of different spoken utterances; and providing the content-independent recognition distribution value for use in a speaker identification process.