Patents by Inventor Michael R. Portnoff

Michael R. Portnoff 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).

  • Patent number: 4246617
    Abstract: Representation of a speech signal by its short-time Fourier transform and the application of this representation to the problem of time compression and expansion of speech are presented. A time-frequency representation for linear time-varying systems is applied to a model for speech production to formulate a quasi-stationary representation for the speech waveform. This representation has the property that simple time scaling of the parameters of the representation corresponds to changing the rate of the speech. Given a real speech signal, short-time Fourier analysis provides a technique for estimating and modifying these parameters. The results of the theoretical analysis are used to design a high-quality speech rate-change system which are simulated on a general-purpose digital mini-computer.
    Type: Grant
    Filed: July 30, 1979
    Date of Patent: January 20, 1981
    Assignee: Massachusetts Institute of Technology
    Inventor: Michael R. Portnoff