Lei Zhang

Department of Computing
The Hong Kong Polytechnic University
Hung Hom, Kowloon, Hong Kong

Office: PQ816

PIC 890

Phone:  852-27667355
Email: cslzhang at comp.polyu dot edu.hk

There are so many unknowns in the universe and life. We are just trying to understand a little ……




Dept. of Automatic Control, Northwestern Polytechnical University, Xi’an, China.



Dept. of Automatic Control, Northwestern Polytechnical University, Xi’an, China.



Dept. of Aeronautical Engineering, Shenyang Inst. of Aeronautical Engineering, Shenyang, China.

Work Experience


Professor, Dept. of Computing, Hong Kong Polytechnic University, Hong Kong.


Associate Professor, Dept. of Computing, Hong Kong Polytechnic University, Hong Kong.


Assistant Professor, Dept. of Computing, Hong Kong Polytechnic University, Hong Kong.


Postdoctoral Fellow, Dept. of Electrical and Computer Engineering, McMaster University, Canada.


Research Assistant/Associate, Dept. of Computing, Hong Kong Polytechnic University, Hong Kong.



The Hong Kong PhD Fellowship Program


2015 Hong Kong Scholars Program





1.    I was selected as the “Highly Cited Researcher” by Thomson Reuters, 2015 (http://highlycited.com).

2.    I’m looking for PhD student, postdoctoral fellow or research assistant/associate in computational photography. Please send me your CV if you have interest. (I will not reply you if I don’t receive your full CV.)

Notes: The minimum English-language requirement of PhD study in PolyU is: TOEFL 90 (with writing at least 23) or IETLS 6.5 (with writing at least 6). 

3.    Some Postdoctoral Fellow, PhD Student, and Research Assistant/Associate positions are available. Any topics on computer vision, pattern recognition and machine learning are fine. Please send me your CV if you have interest.

Newly accepted

1.     J. Xu, L. Zhang, W. Zuo, D. Zhang, X. Feng, “Patch Group Based Nonlocal Self-Similarity Prior Learning for Image Denoising,” in ICCV 2015. (paper, sup) (code) (From “patch” based learning to “patch group” based learning!)

2.     S. Gu, W. Zuo, Q. Xie, D. Meng, X. Feng, L. Zhang, “Convolutional Sparse Coding for Image Super-resolution,” in ICCV 2015. (paper, sup) (code) (State-of-the-art super-resolution result!)

3.     F. Chen, L. Zhang, and H. Yu, “External Patch Prior Guided Internal Clustering for Image Denoising,” ICCV 2015. (paper, sup) (code) (Exploit external and internal information jointly for high performance denoising!)

4.     R. Zhang, L. Lin, R. Zhang, W. Zuo, L. Zhang, “Bit-Scalable Deep Hashing with Regularized Similarity Learning for Image Retrieval and Person Re-identification,” IEEE Trans. on Image Processing, 2015. (paper) (code) (Bit scalable and deep hashing!)

5.     Lin Zhang, Lei Zhang, and Alan C. Bovik, “A Feature-Enriched Completely Blind Image Quality Evaluator,” IEEE Trans. on Image Processing, vol. 24, issue 8, pp. 2579 – 2591, Aug. 2015. (paper) (code and website) (An "opinion-unaware" method which outperforms all "opinion-aware" methods!)

6.     W. Zuo, D. Ren, S. Gu, L. Lin, L. Zhang, “Discriminative Learning of Iteration-wise Priors for Blind Deconvolution,” in CVPR 2015. (paper, sup) (A highly effective blind image deblurring algorithm!)  

7.     F. Wang, W. Zuo, L. Zhang, Deyu Meng, David Zhang, “A Kernel Classification Framework for Metric Learning,” to appear in IEEE Transactions on Neural Networks and Learning Systems. (paper) (code) (We make metric learning hundred to thousand times faster!)

My Google Citation Profile


Recent Research Focus

·       Sparse Representation, Dictionary Learning and Low Rank Methods for Image Restoration and Low Level Vision

·       Collaborative Representation based Classifier

·       Image Quality Assessment

·       Visual Tracking

·       Image Segmentation and Image Segmentation Evaluation

·       Biometrics (face, finger-knuckle-print and palmprint) 


PhD Students Supervised


Biometrics, Computer Vision and Image Processing

Graduated in 2011; now with Tongji University, Shanghai, China


Image Segmentation and Graph-based Optimization

Graduated in 2011; now with Southwest Jiaotong University, Chengdu, China


Texture Classification, Dictionary Learning and Sparse Representation

Graduated in 2012; now doing postdoc at New York University at Dubai


Face Recognition, Sparse Representation and Computer Vision

Graduated in 2012; now with Shenzhen University, Shenzhen, China

ZHANG Kaihua

Visual Tracking, Image Segmentation and Level Set Methods

Graduated in 2013; now with Nanjing Univ. of Information Engineering, Nanjing, China

ZHU Pengfei

Metric Learning, Computer Vision and Pattern Classification

Graduate in 2014; now with Tianjin University, Tianjin, China

GU Shuhang

Image Restoration, Computer Vision, Low Rank and Matrix Factorization

Expected to graduate in 2016

XU Jun

Sparse and Low Rank Methods, Computer Vision, Machine Learning

Expected to graduate in 2017

CAI Sijia

Machine Learning, Computer Vision

Expected to graduate in 2017

LI Hui

HDR Imaging, Multiple Exposure Fusion

Expected to graduate in 2018

CAI Jianrui

Visual Tracking, Scene Understanding

Expected to graduate in 2018

YANG Lingxiao

Object Detection, Visual Recognition

Expected to graduate in 2018


Image Restoration, Image Modeling

Expected to graduate in 2019


Research Collaborators

ZUO Wangmeng

Image Processing, Computer Vision, Machine Learning

Harbin Institute of Technology, Harbin, China

LIN Liang

Computer Vision, Machine Learning, Multimedia

Sun Yat-Sen University, Guangzhou, China


Matrix Factorization, Machine Learning

Xi’an Jiaotong University, Xi’an, China

LI Peihua

Computer Vision, Machine Learning

Dalian University of Technology, Dalian, China