Patents by Inventor Naigang Zhang

Naigang Zhang 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: 11967123
    Abstract: Provided is a binarization method for CT sectional image of fiber package containing artifacts, which includes: performing brightness adjustment on the source image obtained after converting of the HSV image model by using a composite tangent function; creating a planar morphological structural element having a morphology similar to that of a target object to obtain a background image without the target object; obtaining a second intermediate image by a subtraction operation of the first intermediate image and the background image; improving an image contrast of the second intermediate image again to obtain a third intermediate image; and binarizing the third intermediate image by using a local adaptive threshold binarization algorithm and removing a background noise to obtain a final binarized image. The binarization method can improve the uneven brightness of the image under complex illumination, alleviate the artifacts, and strip similar objects from the background with similar gray scales.
    Type: Grant
    Filed: November 1, 2023
    Date of Patent: April 23, 2024
    Assignee: XIDIAN UNIVERSITY
    Inventors: Tengyin Shi, Yiqun Zhang, Zhuo Zhang, Hongzhang Feng, Shen Li, Dongwu Yang, Naigang Hu, Yongxi He
  • Publication number: 20080080702
    Abstract: A method, system, and computer-readable medium for calculating a minimum echo path delay are provided. An accurate calculation of a minimum echo path delay is made based on characteristics of the echo path. The minimum echo path delay calculation may be periodically repeated thus providing for dynamic calculation of the minimum echo path delay in a manner that accounts for variations in echo path characteristics. The minimum echo path delay may be calculated based on discrete processing latencies identified in the echo path, by a network round trip delay, or by modeling an acoustic echo of an in-band audio signal, performing a frequency analysis thereon to calculate a spectrum signature of the modeled acoustic echo, and monitoring a send path for a match with the modeled acoustic echo after applying an instance of the in-band audio signal into the echo path.
    Type: Application
    Filed: October 3, 2006
    Publication date: April 3, 2008
    Applicant: SANTERA SYSTEMS, INC.
    Inventors: Naigang ZHANG, Allen Y. TONG, Sam O. PERRY, Kuang-I SHU
  • Patent number: 6055310
    Abstract: Apparatus to permit recognition of a G.165 sampled tone to allow for disabling an echo canceller determines a phase change in the sampled tone. The apparatus comprises a FIFO buffer which receives an input sampled tone and temporarily stores samples from the input sampled tone on a FIFO basis presenting a delayed sampled tone to an adaptive filter core. The core is also input by the input sampled tone. The adaptive filter core introduces a variable delay to the delayed sampled tone such that a phase difference between the input sampled tone and the output of the adaptive filter core iteratively achieves an integer multiple of 2.pi.. The apparatus includes a filter freezer for, after the phase difference achieves a multiple of 2.pi., freezing the adaptive filter such that the adaptive filter the delay in the signal imposed by the adaptive filter is set regardless of any phase difference thereafter arising between the input sampled tone and the output of said adaptive filter core.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: April 25, 2000
    Assignee: Nortel Networks Corporation
    Inventors: Naigang Zhang, Quentin Meek