Voice assistant optimization dependent on vehicle occupancy

A vehicle system for classifying spoken utterance within a vehicle cabin as one of system-directed and non-system directed, the system comprising:

• at least one sensor configured to detect at least one occupancy signal from at least one occupant of a vehicle, wherein the occupancy signal is indicative of a presence of an occupant;
• and
• a processor programmed to:
• receive at least one audio signal from a vehicle microphone, and
• determine a number of occupants based at least in part on the occupancy signal;
• determine a classification threshold based at least in part on the number of occupants to apply to a probability that acoustic utterances spoken by at least one of the vehicle occupants is a system directed utterance.

A method for classifying spoken utterance as one of system-directed and non-system directed, the method comprising:

• receiving at least one signal indicative of a number of vehicle occupants,
• receiving at least one utterance from one of the vehicle occupants;
• identifying the one of the vehicle occupants;
• determining a probability that the at least one utterance is system directed;
• and
• determining a classification threshold based at least in part on the number of vehicle occupants and occupant-specific factors associated with the one of the vehicle occupants;
• and
• comparing the classification threshold to the probability to determine whether the at least one utterance is one of a system directed utterance and a non-system directed utterance.