Patents by Inventor Johan Paul Linnartz

Johan Paul Linnartz 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).

  • Publication number: 20070044139
    Abstract: A system for authenticating a physical object includes an enrolment device, an authentication device, and a storage for storing authentication data. The enrolment device includes an input for receiving a property set Y of the object measured using a measurement procedure. A processor is used for creating a property set I from the measured property set Y that meet a predetermined robustness criterion. It then creating a property set A from the property set I that includes less information on the actual properties than property set Y, and finally generates a control value Vin dependence on properties of the property set A. An output is used for supplying the control value to the storage as part of the authentication data. The enrolment device operates in an analogous way.
    Type: Application
    Filed: May 13, 2004
    Publication date: February 22, 2007
    Inventors: Pim Tuyls, Theodoru Jacobus Denteneer, Johan Paul Linnartz, Evgeny Verbitskiy
  • Publication number: 20060274614
    Abstract: PHNL031053 An apparatus for processing data from an optical disk (20) generates a data signal by decoding information from the track (21) and a track position signal that is indicative of the radial position and/or depth of the track (21), and/or jitter in the position of edges of bit signals from the track (21). From the track position signal, values of plurality of characteristic measures are computed so that the computed values are substantially invariant under a phase of disk rotation, for example by determining the absolute values of Fourier transform components at multiples of the revolution frequency. Conditional use of the data signal is controlled dependent on the values computed for the characteristic measures. In one embodiment access is granted when the computed values match predetermined values for the disk.
    Type: Application
    Filed: August 27, 2004
    Publication date: December 7, 2006
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Antonius Akkermans, Johan Paul Linnartz
  • Publication number: 20060093080
    Abstract: A diversity receiver has multiple antenna receiving branches. Each branch has means for estimating at least a receiving channel parameter, and the channel parameter estimating means in one branch are coupled to the channel parameter estimating means in an other branch. This way at least a part of the channel parameter estimate in the one branch is used as an aid for estimating at least a receiving channel parameter in the other branch. This saves processing time and processing power in the diversity receiver, and even results in a higher accuracy when selecting the best antenna and receiving branch.
    Type: Application
    Filed: November 6, 2003
    Publication date: May 4, 2006
    Inventor: Johan Paul Linnartz
  • Publication number: 20060087950
    Abstract: A method of and device (110) for granting access to content on a storage medium (101), comprising obtaining cryptographic data (Y) from a property (102), such as a wobble, of the storage medium (101), reading helper data (W) from the storage medium (101), and granting the access based on an application of a delta-contracting function to the cryptographic data (Y) and the helper data (W). The delta-contracting function allows the choice of an appropriate value of the helper data (W), such that any value of the cryptographic data (Y) which sufficiently resembles said original primary input value leads to the same output value. Substantially different values of the cryptographic data (Y) lead to different values of the output.
    Type: Application
    Filed: December 24, 2003
    Publication date: April 27, 2006
    Inventor: Johan Paul Linnartz
  • Publication number: 20050254371
    Abstract: A digital media recorder and method of controlling such is shown. During attempts to copy media content such as audio or a video sequences, sub-sequences are extracted from an input media sequence. A digital fingerprint of the sub-sequence is calculated and compared with at least one first reference fingerprint from a database. The outcome of the comparison determines the action to take in the further processing. Recording of the input media sequence on the media carrier is either allowed or obstructed, e.g. disallowed. In the case recording of the sequence is allowed, the database is updated with information that the digital media sequence has been recorded. This has the effect of a “speed bump,” which limits the rate at which those copies of media content can be made, i.e. the effect is that of prohibiting more than a given number of copies within a given time frame.
    Type: Application
    Filed: June 23, 2003
    Publication date: November 17, 2005
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Gijsbrecht Wirtz, Antonius Adrianus Kalker, Antonius Staring, Jaap Haitsma, Johan Paul Linnartz