Patents by Inventor Ken Greenebaum

Ken Greenebaum 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: 20150146107
    Abstract: Media is usually encoded using a non-linear transfer function that approximates human perception to more efficiently allocate codes to areas of dynamic range where human observers are more easily able to perceive differences in signal strength. Many common media operations, e.g., scaling, rotating, and gamut converting, must be performed in a linear representation to be correct and artifact-free. The non-linear transfer functions used are often pure-power functions, such as “gamma” functions. To avoid banding after transformation, as many as 17 bits are needed in the linear-space with 8-bit input. Thus, methods, computer readable media, and systems for reducing the number of bits required in the linear domain are described herein that substitute a piecewise linear function (e.g., a line segment followed by an offset curve) for a pure-power gamma function, such that a slope limit is applied to constrain the number of (additional) linear bits required (over the input precision).
    Type: Application
    Filed: September 30, 2014
    Publication date: May 28, 2015
    Inventors: Ken Greenebaum, Ian Hendry, David Hayward
  • Patent number: 8704859
    Abstract: The techniques disclosed herein use a display device, in conjunction with various optical sensors, e.g., an ambient light sensor or image sensors, to collect information about the ambient conditions in the environment of a viewer of the display device. Use of these optical sensors, in conjunction with knowledge regarding characteristics of the display device, can provide more detailed information about the effects the ambient conditions in the viewer's environment may have on the viewing experience. A processor in communication with the display device may create an ambient model based at least in part on the predicted effects of the ambient environmental conditions on the viewing experience. The ambient model may be used to adjust the gamma, black point, white point, or a combination thereof, of the display device's tone response curve, such that the viewer's perception remains relatively independent of the ambient conditions in which the display is being viewed.
    Type: Grant
    Filed: December 15, 2010
    Date of Patent: April 22, 2014
    Assignee: Apple Inc.
    Inventors: Ken Greenebaum, Brian Christopher Attwell
  • Publication number: 20120081279
    Abstract: The techniques disclosed herein use a display device, in conjunction with various optical sensors, e.g., an ambient light sensor or image sensors, to collect information about the ambient conditions in the environment of a viewer of the display device. Use of these optical sensors, in conjunction with knowledge regarding characteristics of the display device, can provide more detailed information about the effects the ambient conditions in the viewer's environment may have on the viewing experience. A processor in communication with the display device may create an ambient model based at least in part on the predicted effects of the ambient environmental conditions on the viewing experience. The ambient model may be used to adjust the gamma, black point, white point, or a combination thereof, of the display device's tone response curve, such that the viewer's perception remains relatively independent of the ambient conditions in which the display is being viewed.
    Type: Application
    Filed: December 15, 2010
    Publication date: April 5, 2012
    Applicant: Apple Inc.
    Inventors: Ken Greenebaum, Brian Christopher Attwell