Patents by Inventor Kar-Han Tan

Kar-Han Tan 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: 20100253684
    Abstract: Various embodiments of the present invention related to methods for obtaining shadow invariant and shadow-shading invariant images from a single camera image taken with a narrow-band camera sensor and assuming Plankian illuminating conditions.
    Type: Application
    Filed: April 2, 2009
    Publication date: October 7, 2010
    Inventors: Qingxiong Yang, Kar-Han Tan
  • Publication number: 20100245591
    Abstract: A projection system uses a transformation matrix to transform a projection image p in such a manner so as to compensate for surface 5irregularities on a projection surface. The transformation matrix makes use of properties of light transport relating a projector to a camera. A display pipeline of user-supplied image modification processing modules are reduced by first representing the processing modules as multiple, individual matrix operations. All the matrix operations are then combined with, i.e., multiplied to, the transformation matrix to create a modified transformation matrix. The created transformation matrix is then used in place of the original transformation matrix to simultaneously achieve both image transformation and any pre and post image processing defined by the image modification processing modules.
    Type: Application
    Filed: March 26, 2009
    Publication date: September 30, 2010
    Inventors: Kar-Han Tan, Jing Xiao
  • Publication number: 20100245381
    Abstract: For each of multiple image pixels, input color component values of the pixel in an input device-dependent color space are transformed to output color component values in an output device-dependent color space characterized by an output color gamut defined by a respective gamut range for each of the output color components. In this process, the input color component values of the pixel are multiplied with corresponding elements of a device-dependent characterization matrix to produce a set of product values. The output color component values are derived from the product values. The values of a particular one of the output color components are ascertained based on a continuous nonlinear companding function that maps a function input value derived from one or more of the product values to a function output value that increases monotonically with increasing function input values over the respective gamut range of the particular output color component.
    Type: Application
    Filed: March 28, 2009
    Publication date: September 30, 2010
    Inventors: Ramin Samadani, Kar-Han Tan
  • Publication number: 20100245684
    Abstract: A projection system uses a transformation matrix to transform a projection image p in such a manner so as to compensate for surface irregularities on a projection surface. The transformation matrix makes use of properties of light transport relating a projector to a camera. If the resolution a camera is lower than that of a projector within said projection system, then the transformation matrix will have holes where image data corresponding to a projector pixel will have been lost. In this, case, new image are generated to fill-in the holes.
    Type: Application
    Filed: March 27, 2009
    Publication date: September 30, 2010
    Inventors: Jing Xiao, Kar-Han Tan
  • Publication number: 20100238263
    Abstract: Embodiments of the present invention are directed to visual-collaborative systems enabling geographically distributed groups to engage in face-to-face, interactive collaborative video conferences. In one aspect, a visual-collaborative system comprises a transparent display (402) having a first surface (410) and a second surface (412); and a camera system positioned to face the second surface. The display is configured to show images that can be viewed by looking at the first surface. The display is also configured to transmit light scattered off of objects facing the first surface. The light passes through the display and is captured by the camera.
    Type: Application
    Filed: April 29, 2010
    Publication date: September 23, 2010
    Inventors: Ian N. Robinson, Kar-Han Tan
  • Patent number: 7794090
    Abstract: Application of dual photography is simplified by reducing the number of captured images needed to generate a light transport matrix T of (p×q) projection pixel array from (p×q) images to (p+q) images. Manipulation of the light transport matrix is also simplified by replacing the use of a matrix T with an index associating each projection pixel to only non-zero light transport values. By eliminating the use of zero-valued light transport coefficients, the memory and processing requirements for implementing dual photography are greatly reduced. This dual photography technique is applied to the calibration of projector-camera systems. A second method for calibrating projector-camera systems uses a known projection test pattern and a calibrated camera to associate projected markers on a real image to a captured image.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: September 14, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Kar-Han Tan, Jing Xiao, Anoop K. Bhattacharjya
  • Publication number: 20100188557
    Abstract: An image rendition and capture method includes rendering a first image on a surface using a first set of wavelength ranges of light. While the first image is being rendered, a second image is captured using a second set of wavelength ranges of light but not the first set. The second image is of the surface on which the first image is being rendered.
    Type: Application
    Filed: April 9, 2009
    Publication date: July 29, 2010
    Inventors: Kar Han Tan, Daniel George Gelb, Ian N. Robinson
  • Publication number: 20100188548
    Abstract: Embodiments of the present invention are directed to a visual-collaborative system enabling geographically distributed groups to engage in face-to-face, interactive collaborative video conferences. In one aspect, a visual-collaborative system comprises a display screen, a camera system, and a projector. The display screen has a first surface and a second surface, and the camera system is positioned to capture images of objects through the display screen. The projector is positioned to project images onto a projection surface of the display screen, wherein the projected images can be observed by viewing the second surface. The system includes a first filter disposed between the camera and the first surface, where the first filter passes light receives by the camera but substantially blocks the light that is produced by the projector.
    Type: Application
    Filed: April 29, 2009
    Publication date: July 29, 2010
    Inventors: Ian N. Robinson, Kar Han Tan, Ramin Samadani
  • Publication number: 20100188474
    Abstract: Embodiments of the present invention are directed to a visual-collaborative system enabling geographically distributed groups to engage in face-to-face, interactive collaborative video conferences. In one aspect, a visual-collaborative system (400) comprises a display screen, a camera system, and a projector. The display screen (402) has a first surface (410) and a second surface (416), and the camera system is positioned to capture images of objects through the display screen. The projector (404,602,702) is positioned to project images onto the first surface that can be observed by viewing the second surface. The wavelengths of light used to produce the projected images are different from with the wavelengths of light used to capture images.
    Type: Application
    Filed: January 28, 2009
    Publication date: July 29, 2010
    Inventors: Ian N. Robinson, Kar-Han Tan
  • Publication number: 20100150406
    Abstract: Disclosed are systems and methods for masking at least a portion of one image with another image. Aspects of the present invention facilitate the placing of a virtual mask onto an item in an image even if that items moves in subsequent images, such as between different image frames in a video.
    Type: Application
    Filed: December 12, 2008
    Publication date: June 17, 2010
    Inventors: Jing Xiao, Kar-Han Tan, Anoop K. Bhattacharjya
  • Publication number: 20100141651
    Abstract: Disclosed are embodiments of systems and methods for synthesizing a detailed depth map from a video image. In embodiments, the motion vectors decoded from a video stream may be classified into groups by the application of K-Model clustering techniques based on an affine model. In embodiments, a coarse depth map of the image pixels may be generated using the image segmented according to the motion vector clusters. In embodiments, high resolution gradient maps of the image may be generated using the coarse depth map as well as edge information from the image. In embodiments, a surface reconstruction algorithm, such as the Frankot-Chellappa algorithm, may be applied to the high resolution gradient maps to synthesize a detailed depth map of the image. A detailed depth map of an image may be used to render a three-dimensional surface, for example.
    Type: Application
    Filed: December 9, 2008
    Publication date: June 10, 2010
    Inventor: Kar-Han Tan
  • Publication number: 20100141780
    Abstract: A projection system uses a transformation matrix to transform a projection image p in such a manner so as to compensate for surface irregularities on a projection surface. The transformation matrix makes use of properties of light transport relating a projector to a camera. A display pipeline of user-supplied image modification processing modules are reduced by first representing the processing modules as multiple, individual matrix operations. All the matrix operations are then combined with, i.e., multiplied to, the transformation matrix to create a modified transformation matrix. The created transformation matrix is then used in place of the original transformation matrix to simultaneously achieve both image transformation and any pre and post image processing defined by the image modification processing modules.
    Type: Application
    Filed: December 9, 2008
    Publication date: June 10, 2010
    Inventors: Kar-Han Tan, Tomio Sonehara
  • Patent number: 7734088
    Abstract: Methods and systems are disclosed for processing image frames to reduce the bandwidth requirements. Embodiment of the present invention may include mode-specific image frame rendering in photorealistic and non-photorealistic modes, such as outline and cartoon modes. In embodiments, update regions may be identified and reduced by an edge position mask. In embodiments, update regions may be bounded by rectangles and such regions may be reduced in number by merging regions together using various no-cost or cost approaches. To improve compressibility, regions to be transmitted that do not require updating at the receiver may be encoded as transparent.
    Type: Grant
    Filed: January 11, 2007
    Date of Patent: June 8, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Anoop K Bhattacharjya, Victor Ivashin, Kar-Han Tan
  • Publication number: 20100106998
    Abstract: Disclosed are systems and methods for developing robust features for representing data. In embodiments, a linear generative model is computed using data. In embodiments, based upon a robustness measure, a set of features is selected. In embodiments, the set of features may be evaluated to gauge the capacity of the set of features to represent the data. Responsive to the set of features not satisfying an evaluation criterion or criteria, the set of features may be refined until the selected set of features complies with the evaluation criterion or criteria.
    Type: Application
    Filed: October 24, 2008
    Publication date: April 29, 2010
    Inventors: Jing Xiao, Kar-Han Tan, Anoop K. Bhattacharjya
  • Publication number: 20100085425
    Abstract: A 3D image is created by using two digital projectors having overlapping projection regions. The two digital projectors both emit polarized light, and one are arranged at different angles to each other, such that individual images projected from respective digital projectors can be discerned by the use of polarized eyeglasses. Individualized light transport matrices are used to coordinate together the two digital projectors.
    Type: Application
    Filed: October 7, 2008
    Publication date: April 8, 2010
    Inventor: Kar-Han Tan
  • Publication number: 20100021048
    Abstract: Embodiments of the present invention enable fault detection in a printed dot-pattern image. Certain applications of the present invention are its use in various embodiments of a system for inspection of a printed circuit board (“PCB”) substrate. In embodiments, a generated distortion map is based on a comparison of a reconstructed dot-pattern image, a simulated reference bitmap, and an error map representing differences between the reconstructed dot-pattern image and the reference bitmap. In embodiments, the pixels of the distortion map are color coded to identify the locations and types of aberrations that were discovered as a result of the comparison.
    Type: Application
    Filed: July 23, 2008
    Publication date: January 28, 2010
    Inventors: Ali Zandifar, Kar-Han Tan
  • Publication number: 20100020167
    Abstract: Embodiments of the present invention enable image capture, alignment, and registration. Certain applications of the present invention are its use in various embodiments of a system for inspection of a printed circuit board (“PCB”) substrate. In embodiments, an image capture system comprising a camera and a two-dimensional surface supporting an image may be calibrated based on configuration parameters of an image to be captured and of a simulated reference bitmap based on the image. In embodiments, the position of the image to be captured on the two-dimensional surface is determined based on calibration parameters. In embodiments, a sequence of images may be captured of sections of an image that cannot be captured in a single scan. A scan path across the image may be determined that is based in part on calibration parameters.
    Type: Application
    Filed: July 24, 2008
    Publication date: January 28, 2010
    Inventors: Ali Zandifar, Kar-Han Tan, Jing Xiao
  • Publication number: 20090091615
    Abstract: A method and system for optimizing a data structure for manipulation of matrices in a parallel environment limits computational branching. The data structure further is further optimized for linear data storage and synchronization among multiple processing threads.
    Type: Application
    Filed: July 24, 2008
    Publication date: April 9, 2009
    Inventors: Kar-Han Tan, Yong Zhao
  • Publication number: 20090086081
    Abstract: Disclosed are embodiments of systems and methods for identifying features using color information in an image. The image may be formed from one or more display images comprising color information and features or feature components. Because color information may be used to identify features, more than one feature or feature component may be displayed in a display image. Because a plurality of features may be identified in a calibration image, an image system, such as a projector-camera system, can reduce the number of display images needed to calibrate the system.
    Type: Application
    Filed: December 5, 2008
    Publication date: April 2, 2009
    Inventors: Kar-Han Tan, Jing Xiao, Anoop K. Bhattacharjya
  • Publication number: 20090073324
    Abstract: A method and system for compensating for a moving object placed between a projector and a projection scene is shown. The method/system dividing a movement pattern of the moving object into N discrete position states, and for each of said N position states determining a corresponding view projection matrix. While projecting an image within any of the N position states, multiplying a desired projection image by the corresponding view projection matrix.
    Type: Application
    Filed: June 18, 2008
    Publication date: March 19, 2009
    Inventors: Kar-Han Tan, Edward Bagg