Patents by Inventor John Stach

John Stach 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: 20020172396
    Abstract: A signal embedder hides auxiliary data in a media signal such that the auxiliary data is humanly imperceptible yet recoverable by an automated auxiliary data reader. The embedding method comprises segmenting the media signal into regions, determining statistics for the regions, and adapting quantization bins for each region based on the statistics calculated for the region. To hide auxiliary data in the regions, the method quantizes signal characteristics in the regions into the quantization bins adapted for the regions. The quantization bins correspond to auxiliary data symbols and the signal characteristics are quantized into selected bins depending on the auxiliary data symbol to be embedded in the signal characteristics. A compatible reading method performs a similar adaptive process to define the quantization bins before mapping signal characteristics into the adapted bins to extract the hidden data.
    Type: Application
    Filed: March 22, 2002
    Publication date: November 21, 2002
    Inventors: John Stach, Hugh L. Brunk, Ravi K. Sharma
  • Publication number: 20020136429
    Abstract: The present invention provides steganographic embedding techniques. A digital watermark signal is reduced to a set of spatial positions. The set of spatial positions sufficiently conveys the digital watermark signal. Message objects are positioned according to the set of spatial positions. Non-message objects are combined with the message objects to form an image or design. The message objects include distinguishable characteristics, e.g., via color, contrast, gray-scale level or luminance, in comparison to the non-message objects. The digital watermark signal is detected by distinguishing the message objects from the non-message objects (e.g., via color or contrast differences) and analyzing the relative placement of the message objects within the image or design.
    Type: Application
    Filed: February 11, 2002
    Publication date: September 26, 2002
    Inventors: John Stach, Geoffrey B. Rhoads