Patents by Inventor Raja Bala

Raja Bala 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: 20120001934
    Abstract: Methods and a system for a natural language control interface are provided to enable a user to modify colors in a digital image. A textual interface is provided to select a color to be modified within the image and a direction of change for the modification. A swipe interface is provided to select a magnitude and polarity for the modification. Actions on the textual and swipe interface are converted to natural language commands which are in turn used to derive a color transformation that is applied to relevant portions of the image to yield a modified image. The modifications are displayed in real time for a user to observe as they are inputted.
    Type: Application
    Filed: June 30, 2010
    Publication date: January 5, 2012
    Applicant: XEROX CORPORATION
    Inventors: Raja Bala, Karen M. Braun, Yonghui Zhao, Zahra Langford, Robert J. Rolleston
  • Patent number: 8085434
    Abstract: The appearance of a color print viewed under UV illumination is predicted using a target comprising color patches each printed using a known coverage of printer colorant(s). In one case, the target is illuminated using a UV light source and an electronic image of the target is captured using a digital camera or the like. In another case, a spectrophotometer is used both with and without a UV cutoff filter to measure the target. The captured image data or the spectrophotometric measurements are used to derive a UV printer characterization model that relates any arbitrary combination of printer colorants to a predicted UV color appearance value. Metameric colorant mixture pairs for visible light and UV light viewing can be determined using the UV model together with a conventional visible light printer characterization model. A visual matching task is used to determine a correction factor for the UV printer characterization model.
    Type: Grant
    Filed: March 21, 2008
    Date of Patent: December 27, 2011
    Assignee: Xerox Corporation
    Inventors: Raja Bala, Yonghui Zhao
  • Publication number: 20110303571
    Abstract: Systems and methods are described that facilitate generating a color interference effect during opening and closing of a package for a product. The package includes first and second portions, each having printed thereon a color interference pattern. All or part of the second package portion is transparent, permitting the color interference pattern on the first package portion to be seen through the second package portion. The package portions are mated together (e.g., in a tube and sleeve arrangement or the like), such that the color interference patterns are aligned and overlap each other completely when the package is closed. As the package is opened (or closed), the interference patterns move or slide past each other, creating the visible color interference effect.
    Type: Application
    Filed: June 15, 2010
    Publication date: December 15, 2011
    Applicant: XEROX CORPORATION
    Inventors: Robert P. Loce, Barry G. Gombert, Raja Bala
  • Publication number: 20110305389
    Abstract: What is disclosed is a novel system and method for generating a hierarchical LUT for implementing a color transformation within a color imaging system. In one embodiment, a coarse LUT is received which comprises a plurality of sub-cubes arrayed on a plurality of coarse levels on a structured coarse grid. Each of the sub-cubes encompasses at least one coarse LUT node. Sub-cubes in the coarse grid are identified that are bisected by a boundary surface of the gamut. Then, each of the identified coarse LUT sub-cubes are associated with fine LUT which comprises a plurality of fine LUT nodes arrayed on a plurality of fine levels on a structured fine grid. A hierarchical LUT is generated from the coarse LUT and the associated fine LUTs. Thereafter, the hierarchical LUT can be used for color transformation within a color imaging system.
    Type: Application
    Filed: June 15, 2010
    Publication date: December 15, 2011
    Applicant: Xerox Corporation
    Inventors: Martin S. Maltz, Raja Bala, Lalit Keshav Mestha
  • Patent number: 8077352
    Abstract: An image processing apparatus, program product, and method determine an achievable gamut achievable by the imaging engine or engines for all spatial locations of an output image, or all utilized print engines. A reference gamut is calculated which is any gamut containing the achievable gamut. A gamut mapping is used to map gamuts from the mean gamut to the achievable gamut, and a set of transformations is calculated for each of a set of input colors to a set of target colors selected from colors in the achievable gamut. Values for a received digital image are transformed for each image pixel or clusters of pixels based on the calculated set of transformations. Output images are generated based on the transformed values.
    Type: Grant
    Filed: January 26, 2009
    Date of Patent: December 13, 2011
    Assignee: Xerox Corporation
    Inventors: Edgar Bernal, Robert P Loce, Raja Bala
  • Patent number: 8072648
    Abstract: The predicted tone response curve for each color channel and halftone is predicted using a binary printer model and stored, wherein the “predicted tone response curve” provides a model based approximation of the actual response for the printer for each addressable pixel location in the spatial range. Also stored is an “average predicted tone response” by averaging the “predicted tone response curve” over the spatial range of the printer. With the “true average” tone response curve, the “predicted tone response curve”, and the “average predicted tone response curve”, an estimate of the true tone response curve for the color channel can then be mathematically obtained, wherein the true tone response curve defines a predicted actual response for the printer for each addressable print location in the spatial range. The “predicted” and “average” tone response curves are obtained using the 2×2 binary printer model.
    Type: Grant
    Filed: July 26, 2007
    Date of Patent: December 6, 2011
    Assignee: Xerox Corporation
    Inventors: Vishal Monga, Shen-Ge Wang, Raja Bala
  • Publication number: 20110286015
    Abstract: What is disclosed is a novel system and method for converting a set of L*a*b* values to CMYK color space in which all CMYK formulations that produce each L*a*b* value are found and enumerated. The CMYK formulations are found through a search algorithm starting with the lightest L*a*b* values then visiting neighboring L*a*b* values until the entire L*a*b* color set has been processed. The CMYK space is tessellated into a set of pentahedrons, and for each L*a*b* value, an enclosing pentahedron is found and the CMYK values corresponding to where the locus of this point penetrates each surface is recorded. Adjacent pentahedrons are then visited and this process continues until the gamut boundary is reached. The result is a piecewise linear representation of the CMYK locus containing all values that will give the target L*a*b* value. The present method provides a flexible and powerful approach for solving color management problems.
    Type: Application
    Filed: May 18, 2010
    Publication date: November 24, 2011
    Applicant: Xerox Corporation
    Inventors: Martin S. Maltz, Raja Bala, Yonghui Zhao, Matthew Frederick Hoffmann
  • Patent number: 8064100
    Abstract: A system is employed to reveal a watermark in a document. A watermark generator is utilized to select the placement and at least one colorant combination of an image and at least one colorant combination for a watermark on a document, where the at least one colorant combination of the image and the watermark form a metameric pair. A printing system receives data from the watermark generator and places the image and the watermark on the document. A decoder comprising a narrow band illumination element is selected or tuned to a wavelength corresponding to the colorant combinations utilized by the printing system to reveal the watermark placed thereon.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: November 22, 2011
    Assignee: Xerox Corporation
    Inventors: Karen M. Braun, Raja Bala, Robert P. Loce
  • Patent number: 8064637
    Abstract: A method and system for identifying a fluorescence mark in a printed document includes using an image acquisition device to derive an input digital image. For each pixel of at least one of the input image color channels, the gray value is adjusted to define a filtered digital image including a plurality of pixels each defined by an adjusted gray value. A binary image is derived that that represents the filtered digital image. The binary image includes a binary representation of the fluorescence mark and a binary representation of the background. At least one morphological operation is performed on the binary image. An ASCII character for the binary representation of the fluorescence mark (or each constituent character thereof) is derived and compared to a known security code to authenticate the printed document.
    Type: Grant
    Filed: August 14, 2008
    Date of Patent: November 22, 2011
    Assignee: Xerox Corporation
    Inventors: Raja Bala, Reiner Eschbach, Yonghui Zhao
  • Patent number: 8059134
    Abstract: A method of retaining original natural language commands along with the mathematical LUT transform of the commands and a private tag within the same ICC profile. The private tag can be read only by an exclusive or proprietary application or color management module. When a user loads a color editing profile into the proprietary application, the natural language commands could then be read from the private tag and displayed on a user interface. The user can then immediately see the qualitative effect of the color editing profile and provide selected modifications to the commands and retain a new set of commands stored in another profile.
    Type: Grant
    Filed: October 7, 2008
    Date of Patent: November 15, 2011
    Assignee: Xerox Corporation
    Inventors: Raja Bala, Geoffrey J Woolfe
  • Patent number: 8049929
    Abstract: Aspects of color of a halftoned image are controlled or adjusted. A method for adjustment can include determining a color description of a color of an area or window associated with a target halftoned pixel, determining a desired adjustment to the color associated with the target pixel, determining a color change value based on the desired adjustment and the color description associated with the target pixel, combining the color change value with at least one value of the target halftoned pixel, thereby generating at least one combined target pixel value and quantizing the at least one combined target pixel value. For instance error diffusion and/or rank-ordered error diffusion is used to perform the quantization. Color adjustments can be based on user preference and/or calibration compensations between original and target devices.
    Type: Grant
    Filed: September 2, 2005
    Date of Patent: November 1, 2011
    Assignee: Xerox Corporation
    Inventors: Robert Paul Loce, Beilei Xu, Raja Bala
  • Patent number: 8035688
    Abstract: A computer program product and method for calibrating and characterizing a color display perform calibrating and characterizing steps. A light source is operated in order to emit light from one or more light emitters on the light source. A color capture device, e.g., a digital camera, is calibrated and characterized based on the emitted light. Then, color images are displayed on the color display and captured on the color capture device. The color display is calibrated and characterized based on the captured color images. Computer program instructions are recorded on the computer readable medium, and are executable by a processor, for performing the calibrating and characterizing steps. A method for generating a controlled light source includes displaying light source selections to a user and receiving a user light source selection. Selected light emitters produce a light output matching the user light source selection.
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: October 11, 2011
    Assignee: Xerox Corporation
    Inventors: David Snyderman, Geoffrey John Woolfe, Raja Bala
  • Patent number: 8035855
    Abstract: What is provided herein is a method for automatically selecting a subset of pages from a multi-page document for image processing wherein each selected page is substantially different from all other pages according to certain features of interest and wherein the combined content of the selected pages approximately represents the content in the entire document. Selected pages are clustered wherein each page is represented by a feature vector meaningfully related to the task to be performed. A matrix of feature vectors is analyzed. Basis vectors are extracted from the matrix using rank-reduction techniques. Clustering is performed by subspace projection of page features onto the basis vectors with each page being assigned to a cluster to which that page maximally projects. Representative pages are selected from each cluster. The representative pages can then be used as input to a secondary process.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: October 11, 2011
    Assignee: Xerox Corporation
    Inventors: Vishal Monga, Raja Bala
  • Publication number: 20110222080
    Abstract: This disclosure provides methods, systems and apparatus for jointly optimizing node locations and corresponding output value of a color look-up-table (LUT) associated with an imaging device. According to one exemplary method, initially a set of LUT node locations are generated by solving a first optimization problem and subsequently, a set of LUT node values are generated by solving a second optimization problem.
    Type: Application
    Filed: March 15, 2010
    Publication date: September 15, 2011
    Inventors: Vishal Monga, Raja Bala
  • Publication number: 20110216968
    Abstract: A system and method for resizing a digitally represented color image are presented. A color image with pixels defined by luminance and at least one chrominance value is received. For each pixel of the color image, a luminance spatial variation and respective chrominance spatial variations in the respective neighborhood of the each pixel are computed. The luminance spatial variation and the respective chrominance spatial variations are combined to produce a respective importance value for each pixel. Selected pixels are identified based upon their respective importance values and are removed by seam carving of the color image. The seam carving identifies seams of pixels based upon the respective importance values of pixels within the seams of pixels to create a resized color image. The resized color image is produced to an image output device.
    Type: Application
    Filed: March 5, 2010
    Publication date: September 8, 2011
    Applicant: Xerox Corporation
    Inventors: CLAUDE S. FILLION, Vishal Monga, Raja Bala
  • Patent number: 8009329
    Abstract: A fluorescence-based correlation mark is included in a printed document by encoding the correlation mark as phase shifts in the yellow halftone image only of a printed color document. The correlation mark transparency key is likewise printed using only yellow colorant or can be printed in black or with another colorant or mixture of colorants that will appear dark or black when subjected to UV illumination. UV illumination of the document without use of the transparency key, and use of the transparency key without UV illumination of the document are insufficient to reveal the fluorescence-based correlation mark. UV illumination of the document while the transparency key is overlaid with the document will allow the correlation mark to be perceived.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: August 30, 2011
    Assignee: Xerox Corporation
    Inventors: Raja Bala, Shen-Ge Wang, Reiner Eschbach
  • Patent number: 7956867
    Abstract: In accordance with the disclosure, a method is provided for processing color images for rendering on a color image. The method comprises receiving a plurality of device color separations for an image intended for rendering on a color image device; forming at least one intermediate image by interleaving pixels from at least two of the device color separations, compressing the at least one intermediate image in a compression module; decompressing the at least one intermediate image in a decompression module; processing the at least one decompressed intermediate image through a multidimensional calibration transform to output a calibrated device color separation; and, the device color separations include at least three colors.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: June 7, 2011
    Assignee: Xerox Corporation
    Inventors: Raja Bala, Vishal Monga
  • Publication number: 20110129147
    Abstract: This disclosure provides methods, apparatus and systems for performing image processing regression for approximating multidimensional color transformation. According to an exemplary method, a shaping matrix is selected to minimize a cost function associated with a local linear regression representation of the color transformation. In addition, an alternating least squares algorithm is utilized to jointly optimize regression and shaping parameters.
    Type: Application
    Filed: November 30, 2009
    Publication date: June 2, 2011
    Applicant: XEROX CORPORATION
    Inventors: Vishal Monga, Raja Bala
  • Patent number: 7933053
    Abstract: A spot color dictionary is fine tuned or updated. Localized color production models are determined for spot colors of interest to be produced by an associated document processing system or printer. Measurements are made of colors of produced spot colors. Optionally, measurements are made of colors of test patches that are based on perturbations from the colors of the spot colors. In determining a model for the production of a target spot color, measurement data related to colors that are closer in color space to a given target color is given a higher weight than is measurement data related to colors that are further in color space from the target color. Accordingly, the model is localized to the region of color space about the target color and therefore, more accurately predicts a colorant recipe for the target color than would interpolation based on a full gamut, or more general model.
    Type: Grant
    Filed: December 1, 2006
    Date of Patent: April 26, 2011
    Assignee: Xerox Corporation
    Inventors: Edul N. Dalal, Wencheng Wu, Raja Bala
  • Patent number: 7903291
    Abstract: A method for encryption of a digital watermark by intelligent halftoning includes receiving image data that define at least a portion of a document to be printed in terms of at least three halftone images corresponding respectively to three printing colorants, each of the three halftone images comprising a plurality of halftone cells. The image data are modified by phase-shifting some of the halftone cells of at least one of the halftone images relative to the other halftone images to encode a watermark within the portion of the document such that the at least one phase-shifted halftone image includes a phase-shifted region and a non-phase-shifted region. The modified image data are used to print the portion of the document on a substrate that will fluoresce when subjected to UV illumination. The printed portion of the document includes a first printed pattern resulting from the phase-shifted region and a second printed pattern resulting from the non-phase-shifted region.
    Type: Grant
    Filed: January 14, 2008
    Date of Patent: March 8, 2011
    Assignee: Xerox Corporation
    Inventors: Raja Bala, Shen-ge Wang, Reiner Eschbach