Patents by Inventor Jianjiang Feng

Jianjiang Feng 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: 10769407
    Abstract: Embodiments of the present disclosure provide a fingerprint registration method and device. The method includes: obtaining a fingerprint to be registered and a target fingerprint, extracting fingerprint features from the fingerprint to be registered and the target fingerprint, in which the fingerprint features include a ridge feature and a phase feature, performing a rough registration using ridge features of the two fingerprints, and then obtaining phase difference information of phase features of the two fingerprints in a phase overlap region, adjusting the rough registration result according to the phase difference information to obtain a final registration result of the two fingerprints. In some embodiments, it does not simply depend on the ridge feature to perform the fingerprint registration and add the phase feature on the basis of the ridge feature, and perform twice registration, thereby improving the accuracy of fingerprint registration.
    Type: Grant
    Filed: August 5, 2017
    Date of Patent: September 8, 2020
    Assignee: TSINGHUA UNIVERSITY
    Inventors: Jianjiang Feng, Jie Zhou, Shihao Li
  • Publication number: 20180285618
    Abstract: Embodiments of the present disclosure provide a fingerprint registration method and device. The method includes: obtaining a fingerprint to be registered and a target fingerprint, extracting fingerprint features from the fingerprint to be registered and the target fingerprint, in which the fingerprint features include a ridge feature and a phase feature, performing a rough registration using ridge features of the two fingerprints, and then obtaining phase difference information of phase features of the two fingerprints in a phase overlap region, adjusting the rough registration result according to the phase difference information to obtain a final registration result of the two fingerprints. In some embodiments, it does not simply depend on the ridge feature to perform the fingerprint registration and add the phase feature on the basis of the ridge feature, and perform twice registration, thereby improving the accuracy of fingerprint registration.
    Type: Application
    Filed: August 5, 2017
    Publication date: October 4, 2018
    Inventors: Jianjiang FENG, Jie ZHOU, Shihao LI
  • Patent number: 9684814
    Abstract: A method for estimating an orientation field of a fingerprint is provided, comprising: obtaining an initial orientation field of a fingerprint, and putting the initial orientation field in a reference coordinate system; obtaining N initial orientation blocks corresponding to the initial orientation field, and obtaining N orientation block sets corresponding to N positions respectively from a fingerprint dictionary; obtaining a similarity between each of the N initial orientation blocks and each orientation block in the N orientation block sets corresponding to the N positions to obtain P similarities, and selecting a preset number of candidate orientation blocks for each position from the orientation block set according to the P similarities; obtaining a compatibility between two candidate orientation blocks corresponding to any two adjacent positions respectively to obtain a plurality of compatibilities; and obtaining a candidate orientation block for each position according to the P similarities and the plu
    Type: Grant
    Filed: April 10, 2014
    Date of Patent: June 20, 2017
    Assignee: TSINGHUA UNIVERSITY
    Inventors: Jie Zhou, Jianjiang Feng, Xiao Yang
  • Patent number: 9552509
    Abstract: A method and a system for rectifying a distorted fingerprint are provided. The method includes following steps. A feature of a distorted fingerprint is extracted, a reference distorted fingerprint whose feature is matched with the feature of the distorted fingerprint is searched for in a reference distorted fingerprint database, a dense distortion field of the reference distorted fingerprint is obtained in the reference distorted fingerprint database and the distorted fingerprint is rectified to a normal one according to the dense distortion field of the reference distorted fingerprint.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: January 24, 2017
    Assignee: TSINGHUA UNIVERSITY
    Inventors: Jianjiang Feng, Jie Zhou, Xuanbin Si
  • Patent number: 9489561
    Abstract: A method and system for estimating a fingerprint pose are provided. The method includes following steps. A fingerprint image to be estimated is input, features are extracted from the fingerprint image to be estimated in all possible center positions and directions, each feature is scored via a classifier and a center position and direction corresponding to a feature of a highest score is selected as a fingerprint pose estimation result.
    Type: Grant
    Filed: June 24, 2014
    Date of Patent: November 8, 2016
    Assignee: TSINGHUA UNIVERSITY
    Inventors: Jianjiang Feng, Jie Zhou, Yijing Su
  • Publication number: 20160275330
    Abstract: A method for estimating an orientation field of a fingerprint is provided, comprising: obtaining an initial orientation field of a fingerprint, and putting the initial orientation field in a reference coordinate system; obtaining N initial orientation blocks corresponding to the initial orientation field, and obtaining N orientation block sets corresponding to N positions respectively from a fingerprint dictionary; obtaining a similarity between each of the N initial orientation blocks and each orientation block in the N orientation block sets corresponding to the N positions to obtain P similarities, and selecting a preset number of candidate orientation blocks for each position from the orientation block set according to the P similarities; obtaining a compatibility between two candidate orientation blocks corresponding to any two adjacent positions respectively to obtain a plurality of compatibilities; and obtaining a candidate orientation block for each position according to the P similarities and the plu
    Type: Application
    Filed: April 10, 2014
    Publication date: September 22, 2016
    Inventors: JIE ZHOU, JIANJIANG FENG, XIAO YANG
  • Publication number: 20160132715
    Abstract: A method and a system for rectifying a distorted fingerprint are provided. The method includes following steps. A feature of a distorted fingerprint is extracted, a reference distorted fingerprint whose feature is matched with the feature of the distorted fingerprint is searched for in a reference distorted fingerprint database, a dense distortion field of the reference distorted fingerprint is obtained in the reference distorted fingerprint database and the distorted fingerprint is rectified to a normal one according to the dense distortion field of the reference distorted fingerprint.
    Type: Application
    Filed: August 22, 2014
    Publication date: May 12, 2016
    Inventors: JIANJIANG FENG, JIE ZHOU, XUANBIN SI
  • Patent number: 9305203
    Abstract: A method for registering a fingerprint image is provided. The method comprises steps of: establishing an orientation field template base according to M training fingerprints, wherein M is a positive integer larger than one; receiving a fingerprint image to be registered; obtaining an initial orientation field of the fingerprint image; obtaining an estimated position and an estimated direction of the fingerprint image according to the initial orientation field and the orientation field template base; and registering the fingerprint image according to a preset position, a preset direction, the estimated position and the estimated direction.
    Type: Grant
    Filed: December 27, 2013
    Date of Patent: April 5, 2016
    Assignee: TSINGHUA UNIVERSITY
    Inventors: Jie Zhou, Jianjiang Feng, Xiao Yang
  • Publication number: 20150347804
    Abstract: A method and system for estimating a fingerprint pose are provided. The method includes following steps. A fingerprint image to be estimated is input, features are extracted from the fingerprint image to be estimated in all possible center positions and directions, each feature is scored via a classifier and a center position and direction corresponding to a feature of a highest score is selected as a fingerprint pose estimation result.
    Type: Application
    Filed: June 24, 2014
    Publication date: December 3, 2015
    Inventors: JIANJIANG FENG, JIE ZHOU, YIJING SU
  • Publication number: 20150036896
    Abstract: A method for registering a fingerprint image is provided. The method comprises steps of: establishing an orientation field template base according to M training fingerprints, wherein M is a positive integer larger than one; receiving a fingerprint image to be registered; obtaining an initial orientation field of the fingerprint image; obtaining an estimated position and an estimated direction of the fingerprint image according to the initial orientation field and the orientation field template base; and registering the fingerprint image according to a preset position, a preset direction, the estimated position and the estimated direction.
    Type: Application
    Filed: December 27, 2013
    Publication date: February 5, 2015
    Inventors: Jie Zhou, Jianjiang Feng, Xiao Yang