Patents by Inventor Chai W. Wu

Chai W. Wu 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: 10707996
    Abstract: A framework for error correction coding that takes into account the difference in bit significance in the source symbols by using an appropriate error metric and minimizing it using a Bayes decoder and an optimized codebook. The Bayes decoder performs better than standard soft and hard minimum distance decoding and the optimized codebook performs better than classical linear block codes, e.g., Hamming codes. The error metric is a norm in information symbol space and is based on a loss function appropriately defined according to an approach for assigning significance to the various bits in the source bit stream. The Bayes decoder of this metric is defined and an optimized codebook generated that optimizes this metric under a noisy channel. The framework for error correction coding is implemented for increased reduncancy in a communications system or a data storage system and is optimized to combat noise in such systems.
    Type: Grant
    Filed: April 6, 2018
    Date of Patent: July 7, 2020
    Assignee: International Business Machines Corporation
    Inventor: Chai W. Wu
  • Publication number: 20190312666
    Abstract: A framework for error correction coding that takes into account the difference in bit significance in the source symbols by using an appropriate error metric and minimizing it using a Bayes decoder and an optimized codebook. The Bayes decoder performs better than standard soft and hard minimum distance decoding and the optimized codebook performs better than classical linear block codes, e.g., Hamming codes. The error metric is a norm in information symbol space and is based on a loss function appropriately defined according to an approach for assigning significance to the various bits in the source bit stream. The Bayes decoder of this metric is defined and an optimized codebook generated that optimizes this metric under a noisy channel. The framework for error correction coding is implemented for increased reduncancy in a communications system or a data storage system and is optimized to combat noise in such systems.
    Type: Application
    Filed: April 6, 2018
    Publication date: October 10, 2019
    Inventor: Chai W. Wu
  • Publication number: 20190228327
    Abstract: Methods and systems for determining control inputs to a manufacturing apparatus to manufacture a product are described. A processor may receive model data including initial state data indicating an initial state of an input material, a set of model control inputs, and target measurement data associated with a target product. The processor may learn a causal predictive model based on the target data. Each state of the causal predictive model may be based on an application of the model control inputs on a previous state of the causal predictive model. The processor may compare a final state of the causal predictive model with the target measurement data to determine a difference. The processor may determine, based on the difference, a set of control inputs to be assigned to one or more controls. The one or more controls may define a design of the manufacturing process of an end product.
    Type: Application
    Filed: January 22, 2018
    Publication date: July 25, 2019
    Inventors: Lior Horesh, Chai W. Wu, Ramesh Natarajan, Raya Horesh, David Nahamoo, Christopher Wildsmith, Michael Widman
  • Patent number: 8625161
    Abstract: Digital halftoning processes for producing a halftone image include, for each pixel in the image: indexing a two-dimensional look up table using a position of the pixel, identifying a threshold value for the pixel from the two-dimensional look up table, creating an index that indexes a three-dimensional lookup table using the threshold value and the position of the pixel, and obtaining an output value for the pixel from the three-dimensional look up table via the index. The digital halftoning processes also produce a halftone representation of the image from output values for corresponding pixels.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: January 7, 2014
    Assignee: International Business Machines Corporation
    Inventors: Larry Ernst, Tadanobu Inoue, Mikel Stanich, Chai W. Wu
  • Patent number: 8282182
    Abstract: Methods and systems herein provide for reducing artifacts during printing. One printing system is operable to prepare a continuous tone image (CTI) for printing onto a print medium by generating an initial half tone image (HTI) based on the CTI. The printing system includes a printer and a print controller. The print controller filters the initial HTI and the CTI with a perceptual filter and determines an error between the filtered CTI and the filtered HTI. The print controller prints the HTI via the printer to determine printer artifacts and processes a scanned version of the printed HTI to determine an error between the filtered CTI and the scanned and filtered HTI. This processing updates the initial HTI and reduces the error between the filtered CTI and the filtered HTI.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: October 9, 2012
    Assignee: Ricoh Production Print Solutions LLC
    Inventors: Kartheek Chandu, Larry M. Ernst, Nenad Rijavec, Mikel J. Stanich, Sreenath R. Vantaram, Chai W. Wu
  • Publication number: 20110246658
    Abstract: The invention provides a method, system, and program product for optimizing data exchange in a peer-to-peer network (PTPN). In one embodiment, the invention provides a method of optimizing real-time data exchange in a peer-to-peer network (PTPN), the method comprising: receiving, from each peer in the PTPN: an upload limit of the peer; a download limit of the peer; and a delay to each other peer in the PTPN; determining, for each peer in the PTPN: a rate at which data may be transferred to at least one other peer in the PTPN (transfer rate); and a rate at which data may be received from at least one other peer in the PTPN (receive rate); and instructing each peer in the PTPN to: transfer data to at least one other peer in the PTPN at the transfer rate; and receive data from at least one other peer in the PTPN at the receive rate.
    Type: Application
    Filed: April 5, 2010
    Publication date: October 6, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES COPORATION
    Inventors: Paolo Dettori, Julio Nogima, Frank A. Schaffa, Peter Westerink, Chai W. Wu
  • Publication number: 20110116135
    Abstract: Digital halftoning processes for producing a halftone image include, for each pixel in the image: indexing a two-dimensional look up table using a position of the pixel, identifying a threshold value for the pixel from the two-dimensional look up table, creating an index that indexes a three-dimensional lookup table using the threshold value and the position of the pixel, and obtaining an output value for the pixel from the three-dimensional look up table via the index. The digital halftoning processes also produce a halftone representation of the image from output values for corresponding pixels.
    Type: Application
    Filed: November 19, 2009
    Publication date: May 19, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Larry Ernst, Tadanobu Inoue, Mikel Stanich, Chai W. Wu
  • Publication number: 20100045722
    Abstract: Methods and systems herein provide for reducing artifacts during printing. One printing system is operable to prepare a continuous tone image (CTI) for printing onto a print medium by generating an initial half tone image (HTI) based on the CTI. The printing system includes a printer and a print controller. The print controller filters the initial HTI and the CTI with a perceptual filter and determines an error between the filtered CTI and the filtered HTI. The print controller prints the HTI via the printer to determine printer artifacts and processes a scanned version of the printed HTI to determine an error between the filtered CTI and the scanned and filtered HTI. This processing updates the initial HTI and reduces the error between the filtered CTI and the filtered HTI.
    Type: Application
    Filed: August 24, 2009
    Publication date: February 25, 2010
    Inventors: Kartheek Chandu, Larry M. Ernst, Nenad Rijavec, Mikel J. Stanich, Sreenath R. Vantaram, Chai W. Wu
  • Patent number: 7489419
    Abstract: A halftone spot function, for determining a shape of a halftone spot as a function of the intensity of an image being printed, is generated by creating one or two line segments forming a part of the shape of the spot function or by creating a number of contour lines that are interpolated to form the function. A halftone spot pattern is generated as a number of supercells, each of which includes a number of halftone spots, each defined within a halftone spot cell by a halftone spot function, with the supercell being defined to include a number of device pixels, each of which is fully inked of left without ink, a number of spot cells in each direction, and offset distance establishing angles of the lines dividing the spot cells from one another.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: February 10, 2009
    Assignee: Infoprint Solutions Company, LLC
    Inventors: Huy A. Nguyen, Mikel J. Stanich, Gerhard R. Thompson, Chai W. Wu
  • Patent number: 6982625
    Abstract: An electronic event recorder for attachment to a vehicle is provided which can broadcast encrypted signature and data, thereby leaving behind an electronic version of a “fingerprint” in the event of an accident or traffic violation. The fingerprint, captured by an external data acquisition system or another vehicle so equipped, provides a history of events related to the vehicle. The event recorder is preferably integrated on a smart card and housed in a tamper proof casing. In a first mode of operation, monitoring stations along the roadways periodically send an interrogation signal, such as when radar detects that the vehicle is speeding. Upon receiving the interrogation signal the smart card transmits the vehicle's signature information to the monitoring station where it is time and date stamped along with the speed of the vehicle.
    Type: Grant
    Filed: November 25, 2003
    Date of Patent: January 3, 2006
    Assignee: International Business Machines Corporation
    Inventors: Timothy J. Chainer, Claude A. Greengard, Charles P. Tresser, Chai W. Wu
  • Patent number: 6834344
    Abstract: A method is presented for marking high-quality digital images with a robust and invisible watermark. It requires the mark to survive and remain detectable and authenticatable through all image manipulations that in themselves do not damage the image beyond useability. These manipulations include JPEG “lossy” compression and, in the extreme, the printing and rescanning of the image. The watermark also has the property that it can detect if the essential contents of the image has changed. The first phase of the method comprises extracting a digest or number N from the image so that N only (or mostly) depends on the essential information content, such that the same number N can be obtained from a scan of a high quality print of the image, from the compressed form of the image, or in general, from the image after minor modifications (introduced inadvertently by processing, noise etc.). The second phase comprises the marking.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: December 21, 2004
    Assignee: International Business Machines Corporation
    Inventors: Gaurav Aggarwal, Pradeep K. Dubey, Ashutosh Kulshreshtha, Marco Martens, Charles P. Tresser, Chai W. Wu
  • Publication number: 20040218220
    Abstract: A method and system for performing enhanced error diffusion on a digital image is disclosed. The method and system include gathering statistics in a neighborhood of pixels around a current pixel to detect an amount of contrast in the neighborhood of pixels, and varying a threshold value in relation to the amount of detected contrast. According to the present invention, the amount of detected contrast is used to determine to what extent the neighborhood of pixels comprises an edge region or a non-edge region of the image in relation. Any distributed error assigned to the current pixel is added to the current pixel to obtain a new current pixel value. An output value for a pixel in the neighborhood of pixels is set based on whether the pixel value is less than, or greater or equal to, the threshold value.
    Type: Application
    Filed: April 29, 2003
    Publication date: November 4, 2004
    Applicant: International Business Machines Corporation
    Inventors: Gerhard R. Thompson, Chai W. Wu, Hong Li, Mikel J. Stanich
  • Patent number: 6807634
    Abstract: A digital watermarking method encodes different pairs of watermarks into each of a plurality of images offered for use by a vendor. The watermarks in each pair are derived from two separate collections of watermarks and sufficiently different so as to prevent false positives. Because each pair of watermarks is assigned to a different customer relative to a particular image, unauthorized use of a digital image sold to a customer may be determined by locating the associated pair of watermarks assigned to the customer in the image. Collusion detection is also realized by forming each pair of masks from sub-collections of masks which are detectable in an image formed by combining the same images sold to one or more customers.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: October 19, 2004
    Assignee: International Business Machines Corporation
    Inventors: Gordon W. Braudaway, Marco Martens, Frederick C. Mintzer, James B. Shearer, Charles P. Tresser, Chai W. Wu
  • Publication number: 20040104823
    Abstract: An electronic event recorder for attachment to a vehicle is provided which can broadcast encrypted signature and data, thereby leaving behind an electronic version of a “fingerprint” in the event of an accident or traffic violation. The fingerprint, captured by an external data acquisition system or another vehicle so equipped, provides a history of events related to the vehicle. The event recorder is preferably integrated on a smart card and housed in a tamper proof casing. In a first mode of operation, monitoring stations along the roadways periodically send an interrogation signal, such as when radar detects that the vehicle is speeding. Upon receiving the interrogation signal the smart card transmits the vehicle's signature information to the monitoring station where it is time and date stamped along with the speed of the vehicle.
    Type: Application
    Filed: November 25, 2003
    Publication date: June 3, 2004
    Inventors: Timothy J. Chainer, Claude A. Greengard, Charles P. Tresser, Chai W. Wu
  • Patent number: 6738162
    Abstract: A semi-digital printer includes a print head assembly that prints an image on a sheet of paper that has been mounted onto a turntable, and a rotating means which rotates the turntable so that the print head assembly ejects ink or toner onto the sheet of paper at one or more predetermined angles. The printing may be halftone or color. If the print head assembly includes more than one print head, the rotating means rotates the turntable to a different angle for each print head. By rotating the turntable in this manner, the printer records an image at any angle (0° to 360°) precisely (i.e., without having to perform the angular approximations required by conventional digital printers). As a result, a printed image of improved quality is produced. Alternatively, the semi-digital printer may be configured so that the print head assembly rotates relative to the paper.
    Type: Grant
    Filed: December 9, 1999
    Date of Patent: May 18, 2004
    Assignee: International Business Machines Corporation
    Inventors: Marco Martens, Ravishankar Rao, Gerhard R. Thompson, Charles B. Tresser, Chai W. Wu
  • Patent number: 6737954
    Abstract: An electronic event recorder for attachment to a vehicle is provided which can broadcast encrypted signature and data, thereby leaving behind an electronic version of a “fingerprint” in the event of an accident or traffic violation. The fingerprint, captured by an external data acquisition system or another vehicle so equipped, provides a history of events related to the vehicle. The event recorder is preferably integrated on a smart card and housed in a tamper proof casing. In a first mode of operation, monitoring stations along the roadways periodically send an interrogation signal, such as when radar detects that the vehicle is speeding. Upon receiving the interrogation signal the smart card transmits the vehicle's signature information to the monitoring station where it is time and date stamped along with the speed of the vehicle.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: May 18, 2004
    Assignee: International Business Machines Corporation
    Inventors: Timothy J. Chainer, Claude A. Greengard, Charles P. Tresser, Chai W. Wu
  • Patent number: 6714318
    Abstract: Digital halftoning techniques in printers which construct and utilize a mask in a dithering algorithm for a multitone printer are generalized by using a decision matrix in conjunction with a dithering matrix. For each pixel in the image, pixel grey value and a mask threshold value are obtained. Based on these values, a decision is made on the grey level to be printed at each pixel. For extensions to multiple component color images, each component is treated independently as if it were a grey scale image. The mask threshold values and sizes are likely to be tuned per component and therefore different.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: March 30, 2004
    Assignee: International Business Machines Corporation
    Inventors: Charles H. Morris, III, Joan L. Mitchell, Chai W. Wu, Gerhard R. Thompson, Charles P. Tresser, Nenad Rijavec
  • Patent number: 6603573
    Abstract: A method and apparatus for halftoning digital images renders color data subject to constraints on the number of colorants which can be deposited on a single pixel and constraints on consecutive pixels rendered with the same color. The color data to be rendered is mapped into a second data set in an achievable color gamut space. Then, using a digital halftoning method in the achievable color gamut space, the second data set is rendered, so that the constraints are satisfied.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: August 5, 2003
    Assignee: International Business Machines Corporation
    Inventors: Roy L. Adler, Marco Martens, Joan L. Mitchell, Nenad Rijavec, Robert H. Risch, Charles P. Tresser, Chai W. Wu
  • Patent number: 6597813
    Abstract: A technique combines most of the advantages of both blue noise and clustering in generating a partially clustered aperiodic mask and using it in a dither array algorithm for halftoning, such that the amount of clustering can be modulated. A method to create an enlarged partially clustered aperiodic dither mask, appearing as a modulated version of a periodic enlargement of original mask, is used when the original mask generates patterns that are not visually pleasing or the original mask doesn't generate enough distinct grey levels. The method of halftoning of grey scale images utilizes a pixel-by-pixel comparison of the image against a partially clustered aperiodic mask in which the clustered aperiodic mask is comprised of a partly random and partly deterministic single valued function which is designed to produce visually pleasing dot configurations when thresholded at any level of grey.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: July 22, 2003
    Assignee: International Business Machines Corporation
    Inventors: Mikel J. Stanich, Gerhard R. Thompson, Charles P. Tresser, Chai W. Wu
  • Patent number: 6564322
    Abstract: A watermark in the form of an added message is attached to a digital recording so that a significant content of the recording is completely unchanged by the process in the sense that any reader commonly used for such recording will extract from the recording exactly what would have been extracted in the case the added message had not been attached. This is done by hiding the added message in the error correcting code (ECC) for the significant content of the recording.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: May 13, 2003
    Assignee: International Business Machines Corporation
    Inventors: David H. Jameson, Charles P. Tresser, Chai W. Wu, Steven R. Abrams, Shmuel Windgrad