Abstract: There is provided a speech synthesizer comprising a processor configured to receive one or more linguistic units, convert said one or more linguistic units into a sequence of speech vectors for synthesizing speech, and output the sequence of speech vectors. Said conversion comprises modelling higher and lower spectral frequencies of the speech data as separate high and low spectral streams by applying a first set of one or more statistical models to the higher spectral frequencies and a second set of one or more statistical models to the lower spectral frequencies.

Abstract: A controller for a dialog manager, the dialog manager being configured to receive a representation of an input utterance from a user and control the flow of conversation with the user. The controller is configured to implement a parameterized policy for defining the behavior of a dialog manager. The parameterized policy is configured to operate with an ontology-independent parameter as an input. The controller has a processor for parameterizing an end user ontology such that the parameterized policy can define the behavior of a dialog manager for the end user ontology. The processor is configured to define a slot of the end user ontology in terms of at least one of the ontology-independent parameters such that it is suitable for being used as an input to the parameterized policy.

Abstract: There is provided a speech synthesiser comprising a processor configured to receive one or more linguistic units, convert said one or more linguistic units into a sequence of speech vectors for synthesising speech, and output the sequence of speech vectors. Said conversion comprises modelling higher and lower spectral frequencies of the speech data as separate high and low spectral streams by applying a first set of one or more statistical models to the higher spectral frequencies and a second set of one or more statistical models to the lower spectral frequencies.

Abstract: A controller for a dialogue manager, the dialogue manager being configured to receive a representation of an input utterance from a user and control the flow of conversation with the user. The controller is configured to implement a parameterised policy for defining the behaviour of a dialogue manager. The parameterised policy is configured to operate with an ontology-independent parameter as an input. The controller has a processor for parameterising an end user ontology such that the parameterised policy can define the behaviour of a dialogue manager for the end user ontology. The processor is configured to define a slot of the end user ontology in terms of at least one of the ontology-independent parameters such that it is suitable for being used as an input to the parameterised policy.

Abstract: Natural-sounding synthesized speech is obtained from pieced elemental speech units that have their super-class identities known (e.g. phoneme type), and their line spectral frequencies (LSF) set in accordance with a correlation between the desired fundamental frequency and the LSF vectors that are known for different classes in the super-class. The correlation between a fundamental frequency in a class and the corresponding LSF is obtained by, for example, analyzing the database of recorded speech of a person and, more particularly, by analyzing frames of the speech signal.