Patents by Inventor Roberto Gretter

Roberto Gretter has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Generating confidence scores from word lattices
    Patent number: 7562010
    Abstract: Systems and methods for determining word confidence scores. Speech recognition systems generate a word lattice for speech input. Posterior probabilities of the words in the word lattice are determined using a forward-backward algorithm. Next, time slots are defined for the word lattice, and for all transitions that at least partially overlap a particular time slot, the posterior probabilities of transitions that have the same word label are combined for those transitions. The combined posterior probabilities are used as confidence scores. A local entropy can be computed on the competitor transitions of a particular time slot and also used as a confidence score.
    Type: Grant
    Filed: June 23, 2006
    Date of Patent: July 14, 2009
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Roberto Gretter, Giuseppe Riccardi
  • Generating confidence scores from word lattices
    Patent number: 7092883
    Abstract: Systems and methods for determining word confidence scores. Speech recognition systems generate a word lattice for speech input. Posterior probabilities of the words in the word lattice are determined using a forward-backward algorithm. Next, time slots are defined for the word lattice, and for all transitions that at least partially overlap a particular time slot, the posterior probabilities of transitions that have the same word label are combined for those transitions. The combined posterior probabilities are used as confidence scores. A local entropy can be computed on the competitor transitions of a particular time slot and also used as a confidence score.
    Type: Grant
    Filed: September 25, 2002
    Date of Patent: August 15, 2006
    Assignee: AT&T
    Inventors: Roberto Gretter, Giuseppe Riccardi