Patent ID: 8612225

Claim:
A voice recognition device that recognizes a voice of an input voice signal, comprising: an acoustic model storage unit that stores an acoustic model used for word string search; a voice model storage unit that stores in advance a predetermined voice model having a plurality of detail levels, said plurality of detail levels being information indicating a feature property of a voice for said voice model, the voice model having a size smaller than that of the acoustic model used for word string search; a detail level selection unit that selects a detail level, closest to a feature property of a portion of an input voice signal, from the detail levels of the voice model stored in said voice model storage unit; a parameter setting unit that sets parameters for recognizing the portion of the input voice signal according to the detail level selected by said detail level selection unit, the parameters being set prior to use of the acoustic model to recognize the portion of the input voice signal; and a distance calculation unit that calculates distance information indicating a difference between each of the plurality of detail levels of the voice model stored in the voice model storage unit and the feature property of the input voice signal, wherein the detail level selection unit selects a detail level based on the distance information calculated by the distance calculation unit.