Patents by Inventor Brian R. Walker

Brian R. Walker 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).

  • Temporal synchronization of video watermark decoding
    Patent number: 6785401
    Abstract: A method of synchronizing a watermark decoder with a watermark encoder uses a spatio-temporal (3D) synchronization pattern added to a data pattern to produce a watermark pattern for embedment into a signal. The spatio-temporal synchronization pattern is formed by multiplying a spatial (2D) synchronization pattern with a pseudo-noise sequence for a block of signal frames having a duration of N frames. Quadrature carrier modulation may be used to increase detectability of the watermark pattern at the watermark decoder. The watermarked signal is correlated with the spatial synchronization pattern to recover a temporal synchronization signal that is used to determine a temporal offset between the watermark encoder and watermark decoder. The temporal offset is then used to synchronize the watermark decoder with the watermark encoder.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: August 31, 2004
    Assignee: Tektronix, Inc.
    Inventors: Brian R. Walker, Daniel G. Baker
  • Temporal synchronization of video watermark decoding
    Publication number: 20020164046
    Abstract: A method of synchronizing a watermark decoder with a watermark encoder uses a spatio-temporal (3D) synchronization pattern added to a data pattern to produce a watermark pattern for embedment into a signal. The spatio-temporal synchronization pattern is formed by multiplying a spatial (2D) synchronization pattern with a pseudo-noise sequence for a block of signal frames having a duration of N frames. Quadrature carrier modulation may be used to increase detectability of the watermark pattern at the watermark decoder. The watermarked signal is correlated with the spatial synchronization pattern to recover a temporal synchronization signal that is used to determine a temporal offset between the watermark encoder and watermark decoder. The temporal offset is then used to synchronize the watermark decoder with the watermark encoder.
    Type: Application
    Filed: April 9, 2001
    Publication date: November 7, 2002
    Inventors: Brian R. Walker, Daniel G. Baker