Patents by Inventor Kok Chen

Kok Chen 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: 8587603
    Abstract: Methods and apparatuses for color correction that includes gamma correction. One embodiment of the present invention pre-processes the native device information of a color device (e.g., a color display device) to generate pseudo-native device information such that when a single, unique function is applied on the pseudo-native device information, a customized look up table for gamma correction in a video card is generated. The customized look up table is calibrated for the optimization of color rendering for skin tone in one region in a color space while maintaining the gray colors for the user interface elements in another region in the color space.
    Type: Grant
    Filed: July 10, 2006
    Date of Patent: November 19, 2013
    Assignee: Apple Inc.
    Inventors: Kok Chen, Gabriel G. Marcu, Steve Swen
  • Patent number: 8452090
    Abstract: A system and method for performing Bayer reconstruction of images using a programmable graphics processing unit (GPU) are described herein. A Bayer filtered image in RAW format is uploaded to the GPU, unpacked, and reconstructed. Optionally, the reconstructed image may be transformed into any desired color space and/or displayed by a video card in which the GPU resides. The reconstruction is performed independently on each of the red, blue, and green image fields. The red and blue image fields are reconstructed using first and second interpolation passes in first and second orthogonal directions. Each reconstruction pass preferably employs a two-lobed Lanczos filter. The green image field is interpolated using a single interpolation pass in a direction diagonal to the first and second orthogonal directions, and preferably employs a box filter.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: May 28, 2013
    Assignee: Apple Inc.
    Inventors: Ralph Brunner, Mark Zimmer, Kok Chen
  • Publication number: 20110249141
    Abstract: Methods and apparatuses for color correction of color device for various operating conditions. In at least one embodiment of the present invention, operating under a current condition, a color correction operation that is derived from color correction operations defined for other conditions is performed on the color data. In another embodiment, a device profile for managing colors for a color device operating under one condition is interpolated from the device profiles for the color device operating under other conditions (e.g., based on the input received from a user interface according to the perception of the user or based on the measurement of a sensor). The interpolation can be based on the input received from a user interface according to the perception of the user or it can be based on the measurement of a sensor or a set of sensors. Various operating conditions for a color device (e.g.
    Type: Application
    Filed: June 23, 2011
    Publication date: October 13, 2011
    Inventors: Kok Chen, Gabriel G. Marcu, Wei Chen, John Z.Z. Zhong
  • Patent number: 7969478
    Abstract: Methods and apparatuses for color correction of color device for various operating conditions. In at least one embodiment of the present invention, operating under a current condition, a color correction operation that is derived from color correction operations defined for other conditions is performed on the color data. In another embodiment, a device profile for managing colors for a color device operating under one condition is interpolated from the device profiles for the color device operating under other conditions (e.g., based on the input received from a user interface according to the perception of the user or based on the measurement of a sensor). The interpolation can be based on the input received from a user interface according to the perception of the user or it can be based on the measurement of a sensor or a set of sensors. Various operating conditions for a color device (e.g.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: June 28, 2011
    Assignee: Apple Inc.
    Inventors: Kok Chen, Gabriel G. Marcu, Wei Chen, John Z. Z. Zhong
  • Patent number: 7688328
    Abstract: White point is corrected without degrading luminance on a display device. A white point manager modifies the balance between red, green and blue according to a target white point up to a threshold gray value. As the gray scale approaches white from the threshold gray value, the white point manager blends the balance between red, green and blue from the target white point substantially towards the native white point for the display device, so as not to degrade luminance as the gray scale approaches white.
    Type: Grant
    Filed: November 2, 2005
    Date of Patent: March 30, 2010
    Assignee: Apple Inc.
    Inventors: Kok Chen, Gabriel G. Marcu
  • Patent number: 7460129
    Abstract: A method, device and computer system for creating a smooth, continuous height (scalar or vector) field are described. The described techniques permit arbitrary closed regions to be smoothly shaded without producing unnatural smoothness at the region's edges or boundaries.
    Type: Grant
    Filed: May 7, 2007
    Date of Patent: December 2, 2008
    Assignee: Apple Inc.
    Inventors: Mark Zimmer, Kok Chen
  • Patent number: 7456843
    Abstract: Methods and apparatuses for performing gamma corrections to maintain a plurality of colors substantially consistent with a color point. In one aspect of the present invention, a method to generate correction functions for performing color correction for a device for signals of different color components in a color space includes: generating a first correction function for a first color component in the color space; and generating second correction functions for second color components in the color space by reducing first color differences between a target White point and white points of a plurality of grays corrected by the first and second correction functions. The second color components are the color components in the color space other than the first color component. The first color differences are minimized relative to a chromaticity diagram.
    Type: Grant
    Filed: December 10, 2004
    Date of Patent: November 25, 2008
    Assignee: Apple Inc.
    Inventors: Kok Chen, Gabriel G. Marcu
  • Patent number: 7397964
    Abstract: A Gaussian blur approximation is applied to an image by repeated down-sampling operations followed by an up-sample operation. By using a truncated Gaussian filter as the down-sample filter, the frequency spectrum removed during down-sampling operations closely approximates the frequency spectrum lost during a true Gaussian blur operation. While any “good” up-sample filter may be used, up-sampling via linear interpolation may be especially beneficial in systems having a dedicated graphics processing unit. One benefit of the described technique is that it is computationally less costly to implement than a Gaussian blur. Another benefit is that this computational benefit increases as the size of the blur increases—becoming significant even for small blurs. Yet another benefit of the invention is that a judicious selection of pixel address to convolve with the filter leads to substantially reduced number of texture lookups required to effect a convolution.
    Type: Grant
    Filed: June 24, 2004
    Date of Patent: July 8, 2008
    Assignee: Apple Inc.
    Inventors: Ralph Brunner, Kok Chen, John Harper
  • Publication number: 20080024805
    Abstract: Undesirable artifacts appearing in color images, such as blooming or smudging around the edges of text, are avoided through selective reduction of the color gamut for objects which form the image. Individual component color values are modified by taking into account combinations of colors and their effect upon the artifacts to be eliminated. Only those parameter values which contribute to the artifact are modified. Other parameter values are left intact, to maintain the original image characteristics. When a color value is modified, all components of that color are modified in a symmetrical manner, to preserve the hue of the original color. The impact on the image is further minimized by selectively applying color correction only to those objects in which the artifact is pronounced.
    Type: Application
    Filed: September 25, 2007
    Publication date: January 31, 2008
    Applicant: Apple Inc.
    Inventors: Kevin Andresen, Kok Chen
  • Publication number: 20070206028
    Abstract: A method, device and computer system for creating a smooth, continuous height (scalar or vector) field are described. The described techniques permit arbitrary closed regions to be smoothly shaded without producing unnatural smoothness at the region's edges or boundaries.
    Type: Application
    Filed: May 7, 2007
    Publication date: September 6, 2007
    Applicant: APPLE INC.
    Inventors: Mark Zimmer, Kok Chen
  • Patent number: 7227551
    Abstract: A method, device and computer system for creating a smooth, continuous height (scalar or vector) field are described. The described techniques permit arbitrary closed regions to be smoothly shaded without producing unnatural smoothness at the region's edges or boundaries.
    Type: Grant
    Filed: December 23, 2004
    Date of Patent: June 5, 2007
    Assignee: Apple Inc.
    Inventors: Mark Zimmer, Kok Chen
  • Publication number: 20070121167
    Abstract: Successive frames or images of an input image that are presented to the output device are individually halftoned. A starting location within the input image for tiling one of one or more halftone techniques over the frame or image is determined. The starting location is then offset from the previously used starting location after a certain number of frames or images have been halftoned. Any halftoning technique may be used to halftone the frames or images. The halftoned frames or images are then viewed in a sequence in time.
    Type: Application
    Filed: January 26, 2007
    Publication date: May 31, 2007
    Inventors: Kok Chen, Gabriel Marcu
  • Publication number: 20060250412
    Abstract: Methods and apparatuses for color correction that includes gamma correction. One embodiment of the present invention pre-processes the native device information of a color device (e.g., a color display device) to generate pseudo-native device information such that when a single, unique function is applied on the pseudo-native device information, a customized look up table for gamma correction in a video card is generated. The customized look up table is calibrated for the optimization of color rendering for skin tone in one region in a color space while maintaining the gray colors for the user interface elements in another region in the color space.
    Type: Application
    Filed: July 10, 2006
    Publication date: November 9, 2006
    Inventors: Kok Chen, Gabriel Marcu, Steve Swen
  • Patent number: 7084881
    Abstract: Methods and apparatuses for color correction that includes gamma correction. One embodiment of the present invention pre-processes the native device information of a color device (e.g., a color display device) to generate pseudo-native device information such that when a single, unique function is applied on the pseudo-native device information, a customized look up table for gamma correction in a video card is generated. The customized look up table is calibrated for the optimization of color rendering for skin tone in one region in a color space while maintaining the gray colors for the user interface elements in another region in the color space.
    Type: Grant
    Filed: August 7, 2003
    Date of Patent: August 1, 2006
    Assignee: Apple Computer, Inc.
    Inventors: Kok Chen, Gabriel G. Marcu, Steve Swen
  • Publication number: 20060139369
    Abstract: A method, device and computer system for creating a smooth, continuous height (scalar or vector) field are described. The described techniques permit arbitrary closed regions to be smoothly shaded without producing unnatural smoothness at the region's edges or boundaries.
    Type: Application
    Filed: December 23, 2004
    Publication date: June 29, 2006
    Applicant: Apple Computer, Inc.
    Inventors: Mark Zimmer, Kok Chen
  • Publication number: 20060050080
    Abstract: White point is corrected without degrading luminance on a display device. A white point manager modifies the balance between red, green and blue according to a target white point up to a threshold gray value. As the gray scale approaches white from the threshold gray value, the white point manager blends the balance between red, green and blue from the target white point substantially towards the native white point for the display device, so as not to degrade luminance as the gray scale approaches white.
    Type: Application
    Filed: November 2, 2005
    Publication date: March 9, 2006
    Inventors: Kok Chen, Gabriel Marcu
  • Publication number: 20050286794
    Abstract: A Gaussian blur approximation is applied to an image by repeated down-sampling operations followed by an up-sample operation. By using a truncated Gaussian filter as the down-sample filter, the frequency spectrum removed during down-sampling operations closely approximates the frequency spectrum lost during a true Gaussian blur operation. While any “good” up-sample filter may be used, up-sampling via linear interpolation may be especially beneficial in systems having a dedicated graphics processing unit. One benefit of the described technique is that it is computationally less costly to implement than a Gaussian blur. Another benefit is that this computational benefit increases as the size of the blur increases—becoming significant even for small blurs. Yet another benefit of the invention is that a judicious selection of pixel address to convolve with the filter leads to substantially reduced number of texture lookups required to effect a convolution.
    Type: Application
    Filed: June 24, 2004
    Publication date: December 29, 2005
    Applicant: Apple Computer, Inc.
    Inventors: Ralph Brunner, Kok Chen, John Harper
  • Patent number: 6972772
    Abstract: White point is corrected without degrading luminance on a display device. A white point manager modifies the balance between red, green and blue according to a target white point up to a threshold gray value. As the gray scale approaches white from the threshold gray value, the white point manager blends the balance between red, green and blue from the target white point substantially towards the native white point for the display device, so as not to degrade luminance as the gray scale approaches white.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: December 6, 2005
    Assignee: Apple Computer, Inc.
    Inventors: Kok Chen, Gabriel G. Marcu
  • Patent number: 6954193
    Abstract: A method and apparatus is described for providing a consistent visual appearance of pixels of a display screen with respect to a viewing position. Variations between perceived pixel level values associated with the pixels and corresponding pixel level values may be compensated for. Variations are associated with a viewing angle between pixel location and the viewing position and compensated for by applying a respective different correction factor to each of the corresponding pixel level values based on a respective viewing angle. Accordingly different non-linear correction curves corresponding to locations may be established relating a range of pixel level values to a corresponding range of corrected pixel level values associated with the viewing position. A calibration pattern may be further be displayed and user inputs associated with locations received responsive to calibration pattern.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: October 11, 2005
    Assignee: Apple Computer, Inc.
    Inventors: Jose Olav Andrade, Kok Chen, Peter N. Graffagnino, Gabriel G. Marcu
  • Publication number: 20050099429
    Abstract: Methods and apparatuses for performing gamma corrections to maintain a plurality of colors substantially consistent with a color point. In one aspect of the present invention, a method to generate correction functions for performing color correction for a device for signals of different color components in a color space includes: generating a first correction function for a first color component in the color space; and generating second correction functions for second color components in the color space by reducing first color differences between a target White point and white points of a plurality of grays corrected by the first and second correction functions. The second color components are the color components in the color space other than the first color component. The first color differences are minimized relative to a chromaticity diagram.
    Type: Application
    Filed: December 10, 2004
    Publication date: May 12, 2005
    Inventors: Kok Chen, Gabriel Marcu