Patents by Inventor Lai Chee Man

Lai Chee Man 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: 8014036
    Abstract: A form of stochastic random distribution is used to print an invisible watermark using a typical, e.g., 600 dpi, printer. The watermark contains such information as “Do Not Copy,” or other such information. Although the watermark is not visible on a first generation version of a document that is printed, various techniques are used to print the watermark in such a way that it becomes readily apparent when the first generation document is photocopied. The preferred embodiment of the invention is concerned with a technique for improving such techniques, for example so that gray levels are improved to address variations from printer to printer. Another preferred embodiment of the invention is also concerned with a technique for performing error diffusion watermarking without the need for performing a calibration step.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: September 6, 2011
    Assignee: Electronics For Imaging, Inc.
    Inventor: Lai Chee Man
  • Publication number: 20110085209
    Abstract: A form of stochastic random distribution is used to print an invisible watermark using a typical, e.g., 600 dpi, printer. The watermark contains such information as “Do Not Copy,” or other such information. Although the watermark is not visible on a first generation version of a document that is printed, various techniques are used to print the watermark in such a way that it becomes readily apparent when the first generation document is photocopied. The preferred embodiment of the invention is concerned with a technique for improving such techniques, for example so that gray levels are improved to address variations from printer to printer. Another preferred embodiment of the invention is also concerned with a technique for performing error diffusion watermarking without the need for performing a calibration step.
    Type: Application
    Filed: December 9, 2010
    Publication date: April 14, 2011
    Inventor: Lai Chee MAN
  • Patent number: 7880934
    Abstract: A form of stochastic random distribution is used to print an invisible watermark using a typical, e.g., 600 dpi, printer. The watermark contains such information as “Do Not Copy,” or other such information. Although the watermark is not visible on a first generation version of a document that is printed, various techniques are used to print the watermark in such a way that it becomes readily apparent when the first generation document is photocopied. The preferred embodiment of the invention is concerned with a technique for improving such techniques, for example so that gray levels are improved to address variations from printer to printer. Another preferred embodiment of the invention is also concerned with a technique for performing error diffusion watermarking without the need for performing a calibration step.
    Type: Grant
    Filed: December 6, 2007
    Date of Patent: February 1, 2011
    Assignee: Electronics for Imaging, Inc.
    Inventor: Lai Chee Man
  • Patent number: 7653890
    Abstract: A Wafer Image Modeling and Prediction System (“WIMAPS”) is described that includes systems and methods that generate and/or apply models of resolution enhancement techniques (“RET”) and printing processes in integrated circuit (“IC”) fabrication. The WIMAPS provides efficient processes for use by designers in predicting the RET and wafer printing process so as to allow designers to filter predict printed silicon contours prior to application of RET and printing processes to the circuit design.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: January 26, 2010
    Assignee: Cadence Design Systems, Inc.
    Inventors: Chi-Ming Tsai, Lai-Chee Man, Yao-Ting Wang, Fang-Cheng Chang
  • Patent number: 7636180
    Abstract: Methods and apparatus are provided to smooth a jagged outline of a reconstructed text generated through any of a variety of systems, such as, for example, an image scanner. Given the reconstructed text with a jagged outline, the methods smooth the outline of the text first through location of horizontal and vertical edges, and subsequent gray scale reconstruction of the edge ink level from a one-bit or a low number of bits edge pattern. The methods then provide identification of the local text outline pattern and corresponding ink level adjustment of the center pixel. The methods produce text having very smooth horizontal and vertical edges. The methods then smooth slanted edges, mend holes in the text, and remove isolated pixels of ink.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: December 22, 2009
    Assignee: Electronics for Imaging, Inc.
    Inventors: Ron J. Karidi, Lai Chee Man
  • Patent number: 7307761
    Abstract: A form of stochastic random distribution is used to print an invisible watermark using a typical, e.g. 600 dpi, printer. The watermark contains such information as “Do Not Copy,” or other such information. While the watermark is not visible on a first generation version of a document that is printed, various techniques are used to print the watermark in such a way that it becomes readily apparent when the first generation document is photocopied. The preferred embodiment of the invention is concerned with a technique for improving such techniques, for example so that gray levels are improved to address variations from printer to printer. Another preferred embodiment of the invention is also concerned with a technique for performing error diffusion watermarking without the need for performing a calibration step.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: December 11, 2007
    Assignee: Electronics for Imaging, Inc.
    Inventor: Lai Chee Man
  • Patent number: 7248752
    Abstract: Methods and apparatus are provided for converting binary image data at a first resolution to binary image data at a second resolution, the methods including detecting the edges of the binary image data, sampling a corresponding point on or substantially near each of the edges, fitting a curve between the sampled points, and re-sampling the curve at the second resolution.
    Type: Grant
    Filed: August 27, 2003
    Date of Patent: July 24, 2007
    Assignee: Electronics For Imaging, Inc.
    Inventor: Lai Chee Man
  • Patent number: 7177472
    Abstract: A text detection technique comprises local ramp detection, identification of intensity troughs (candidate text strokes), determination of stroke width, preliminary detection of text based on contrast and stroke width, and a consistency check.
    Type: Grant
    Filed: July 9, 2004
    Date of Patent: February 13, 2007
    Assignee: Electronics for Imaging, Inc.
    Inventors: Ron J. Karidi, Lai Chee Man
  • Publication number: 20050268256
    Abstract: A Wafer Image Modeling and Prediction System (“WIMAPS”) is described that includes systems and methods that generate and/or apply models of resolution enhancement techniques (“RET”) and printing processes in integrated circuit (“IC”) fabrication.
    Type: Application
    Filed: April 1, 2005
    Publication date: December 1, 2005
    Inventors: Chi-Ming Tsai, Lai-Chee Man, Yao-Ting Wang, Fang-Cheng Chang
  • Patent number: 6885477
    Abstract: Methods and apparatus are provided to smooth a jagged outline of a reconstructed text generated through any of a variety of systems, such as, for example, an image scanner. Given the reconstructed text with a jagged outline, the methods smooth the outline of the text first through location of horizontal and vertical edges, and subsequent gray scale reconstruction of the edge ink level from a one-bit or a low number of bits edge pattern. The methods then provide identification of the local text outline pattern and corresponding ink level adjustment of the center pixel. The methods produce text having very smooth horizontal and vertical edges. The methods then smooth slanted edges, mend holes in the text, and remove isolated pixels of ink.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: April 26, 2005
    Assignee: Electronics for Imaging, Inc.
    Inventors: Ron J. Karidi, Lai Chee Man
  • Publication number: 20050047680
    Abstract: Methods and apparatus are provided for converting binary image data at a first resolution to binary image data at a second resolution, the methods including detecting the edges of the binary image data, sampling a corresponding point on or substantially near each of the edges, fitting a curve between the sampled points, and re-sampling the curve at the second resolution.
    Type: Application
    Filed: August 27, 2003
    Publication date: March 3, 2005
    Inventor: Lai Chee Man
  • Publication number: 20040240736
    Abstract: A text detection technique comprises local ramp detection, identification of intensity troughs (candidate text strokes), determination of stroke width, preliminary detection of text based on contrast and stroke width, and a consistency check.
    Type: Application
    Filed: July 9, 2004
    Publication date: December 2, 2004
    Inventors: Ron J. Karidi, Lai Chee Man
  • Patent number: 6778700
    Abstract: A text detection technique comprises local ramp detection, identification of intensity troughs (candidate text strokes), determination of stroke width, preliminary detection of text based on contrast and stroke width, and a consistency check.
    Type: Grant
    Filed: March 14, 2001
    Date of Patent: August 17, 2004
    Assignee: Electronics for Imaging, Inc.
    Inventors: Ron J. Karidi, Lai Chee Man
  • Publication number: 20040114190
    Abstract: A form of stochastic random distribution is used to print an invisible watermark using a typical, e.g. 600 dpi, printer. The watermark contains such information as “Do Not Copy,” or other such information. While the watermark is not visible on a first generation version of a document that is printed, various techniques are used to print the watermark in such a way that it becomes readily apparent when the first generation document is photocopied. The preferred embodiment of the invention is concerned with a technique for improving such techniques, for example so that gray levels are improved to address variations from printer to printer. Another preferred embodiment of the invention is also concerned with a technique for performing error diffusion watermarking without the need for performing a calibration step.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 17, 2004
    Inventor: Lai Chee Man
  • Publication number: 20030123094
    Abstract: Methods and apparatus are provided to smooth a jagged outline of a reconstructed text generated through any of a variety of systems, such as, for example, an image scanner. Given the reconstructed text with a jagged outline, the methods smooth the outline of the text first through location of horizontal and vertical edges, and subsequent gray scale reconstruction of the edge ink level from a one-bit or a low number of bits edge pattern. The methods then provide identification of the local text outline pattern and corresponding ink level adjustment of the center pixel. The methods produce text having very smooth horizontal and vertical edges. The methods then smooth slanted edges, mend holes in the text, and remove isolated pixels of ink.
    Type: Application
    Filed: December 11, 2002
    Publication date: July 3, 2003
    Inventors: Ron J. Karidi, Lai Chee Man
  • Publication number: 20030026480
    Abstract: A text detection technique comprises local ramp detection, identification of intensity troughs (candidate text strokes), determination of stroke width, preliminary detection of text based on contrast and stroke width, and a consistency check.
    Type: Application
    Filed: March 14, 2001
    Publication date: February 6, 2003
    Inventors: Ron J. Karidi, Lai Chee Man
  • Patent number: 6501565
    Abstract: Methods and apparatus are provided to smooth a jagged outline of a reconstructed text generated through any of a variety of systems, such as, for example, an image scanner. Given the reconstructed text with a jagged outline, the methods smooth the outline of the text first through location of horizontal and vertical edges, and subsequent gray scale reconstruction of the edge ink level from a one-bit or a low number of bits edge pattern. The methods then provide identification of the local text outline pattern and corresponding ink level adjustment of the center pixel. The methods produce text having very smooth horizontal and vertical edges. The methods then smooth slanted edges, mend holes in the text, and remove isolated pixels of ink.
    Type: Grant
    Filed: November 21, 2000
    Date of Patent: December 31, 2002
    Assignee: Electronics for Imaging, Inc.
    Inventors: Ron J. Karidi, Lai Chee Man
  • Patent number: 6215306
    Abstract: The quality of spiral images depends on whether actual k-space sampling points are at their nominal positions. Although newer gradient systems can provide more accurate gradient waveforms, timing mis-registration between data acquisition and gradient systems can significantly distort the positions of samples. Even after the timing of data acquisition is tuned, minor residual errors can still cause shading artifacts which are problematic for quantitative MRI applications, such as the phase-contrast method. Although ideally measuring the actual k-space trajectory can correct for the timing errors, it requires additional data acquisition and scan time. The present invention employs off-centered spiral trajectories which are more robust against timing errors and applies them to the phase-contrast method. The new trajectories turn shading artifacts into a slowly-varying linear phase in reconstructed images without affecting the magnitude of images.
    Type: Grant
    Filed: May 14, 1999
    Date of Patent: April 10, 2001
    Assignee: Board of Trustees of the Leland Stanford Junior University
    Inventors: Chi-Ming Tsai, Lai-Chee Man