Fengqiang Li

I obtained my Ph.D. in computer science from Northwestern University, where I worked on computational photography and computer vision with Oliver Cossairt in Computational Photography Lab . I am now a computer vision algorithm engineer at Apple.

Before that, I received my M.S in Electrical Engineering from Lehigh University in 2014, and B.S in Optics from Huazhong University of Science and Technology in 2011. I also worked with Michael Hall and Shuochen Su on stereo for AR devices at Facebook AR/VR in 2019, with Michael Hall on modeling and evaluation of novel ToF cameras at Oculus VR in 2018, and with Emily Cooper on Robotics Vision at Google X in 2016.

Email  /  CV  /  Google Scholar  /  LinkedIn

profile photo
Research

I am working on computational algorithms to improve the quality of 3D imaging using optimization and deep learning. I am interested in 3D imaging from micro-scale OCT to marco scale time-of-flight imaging, Photo Stereo, and photometric stereo. I am also interested in 3D applications powered with state-of-the-art machine/deep learning for high level computer vision problems such as face recognition and SLAM, and machine perceptions in self-driving cars, robots and VR/AR systems.

Adaptive Illumination Based Depth Sensing Using Deep Superpixel and Soft Sampling Approximation
Qiqin Dai, Fengqiang Li, Oliver Cossairt, Aggelos K. Katsaggelos
IEEE Transactions on Computational Imaging (TCI), 2022

Adapptive illumination for depth sesning such as LiDAR.

[Paper] [ArXiv] [Code]
Fast non-line-of-sight imaging with high-resolution and wide field of view using synthetic wavelength holography
Florian Willomitzer, Prasanna V. Rangarajan, Fengqiang Li, Muralidhar M. Balaji, Marc P. Christensen, Oliver Cossairt
Nature Communications, 2021

Non-line-of-sight imaging with synthetic wavelength holography.

[Project webpage] [ArXiv] [Paper] [Northwestern news] [BibTex]
Exploiting wavelength diversity for high resolution time-of-flight 3D imaging
Fengqiang Li*, Florian Willomitzer*, Muralidhar Balaji, Prasanna Rangarajan, Oliver Cossairt (*: co-first author)
IEEE Transactions on Pattern Analysis and Machine Intelligence (TPAMI), 2021
IEEE International Conference on Computational Photography (ICCP), 2021

Computational micro 3D sensing.

[Paper] [Video] [BibTex]
Compressive ghost imaging through scattering media with deep learning
Fengqiang Li*, Ming Zhao*, Zhiming Tian, Florian Willomitzer, Oliver Cossairt (*: co-first author)
OSA Optics Express, 2020

Leverage deep learning and computational ghost imaging through scattering media.

WISHED: Wavefront imaging sensor with high resolution and depth ranging
Yicheng Wu*, Fengqiang Li*, Florian Willomitzer, Ashok Veeraraghavan, Oliver Cossairt (*: co-first author)
IEEE International Conference on Computational Photography (ICCP), 2020

High depth and lateral resolution 3D sensor.

[Project webpage] [BibTex] [Video]
Multi-frame Super-resolution for Time-of-flight Imaging
Fengqiang Li, Pablo Ruiz, Oliver Cossairt, Aggelos K. Katsaggelos
IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), 2019

Achieve SR for depth imaging with multi frames.

SH-ToF: Micro resolution time-of-flight imaging with superheterodyne interferometry
Fengqiang Li, Florian Willomitzer, Prasanna Rangarajan, Mohit Gupta, Andreas Velten, Oliver Cossairt
IEEE International Conference on Computational Photography (ICCP), 2018

Propose a micro depth resolution ToF imaging with optical interferometry.

[Project webpage] [BibTex]
CS-ToF: High-resolution compressive time-of-flight imaging
Fengqiang Li, Huaijin Chen, Adithya Pediredla, Chiakai Yeh, Kuan He, Ashok Veeraraghavan, Oliver Cossairt
OSA Optics Express, 2018

Use compressive sensing to improve the lateral resolution of the off-the-shelf ToF cameras.

[Project webpage] [BibTex]
High-depth-resolution range imaging with multiple-wavelength superheterodyne interferometry using 1550-nm lasers
Fengqiang Li, Joshua Yablon, Andreas Velten, Mohit Gupta, Oliver Cossairt
OSA Applied Optics, 2017

Propose a high depth resolution LIDAR system in 1550nm.

[Project webpage] [BibTex]
Shape-from-Shifting: Uncalibrated Photometric Stereo with a Mobile Device
Chia-Kai Yeh, Fengqiang Li, Gianluca Pastorelli, Marc Walton, Aggelos K. Katsaggelos, Oliver Cossairt
IEEE International Conference on eScience , 2017

Use a mobile device for normal and shape estimation in the wild.

[Project webpage] [BibTex]
A Streamlined Photometric Stereo Framework for Cultural Heritage
Chia-Kai Yeh, Nathan Matsuda, Xiang Huang, Fengqiang Li, Marc Walton, Oliver Cossairt
European Conference on Computer Vision Workshop on Computer Vision for Art Analysis (ECCVW), 2016

Fusion of photogrammetry and photometric stereo for a dense depth map.

[Project webpage] [BibTex]
Nondestructive evaluation of progressive neuronal changes in organotypic rat hippocampal slice cultures using ultrahigh-resolution optical coherence microscopy
Fengqiang Li, Yu Song, Alexandra Dryer, William Cogguillo, Yevgeny Berdichevsky, Chao Zhou
Neurophotonics, 2014

Quantitatively evaluate the neuron number affected by seizures with OCT.

[BibTex]
Label-free evaluation of angiogenic sprouting in microengineered devices using ultrahigh-resolution optical coherence microscopy
Fengqiang Li, Ting Xu, Duc-Huy T Nguyen, Xiaolei Huang, Christopher S Chen, Chao Zhou
Journal of Biomedical Optics, 2014

Label-free and statistically evaluation of angiogenic sprouting with OCT.

[BibTex]
Delineating 3D Angiogenic Sprouting in OCT Images via Multiple Active Contours
Ting Xu, Fengqiang Li, Duc-Huy T Nguyen, Christopher S Chen, Chao Zhou, Xiaolei Huang
Augmented Reality Environments for Medical Imaging and Computer-Assisted Interventions, 2013

Employs multiple Stretching Open Active Contours to quantify the morphological and topological properties of these curvilinear networks.

[BibTex]
Patents

Fengqiang Li, Zihe Gao US11194160 , Granted, 2021

Fengqiang Li, Zihe Gao, Michael Hall, Zhaoming Zhu, Shuochen Su, Huixuan Tang, Xinqiao Liu, Nicholas Daniel Trail US11195291 , Granted, 2021

Fengqiang Li, Michael Hall US10939089 , Granted, 2021

Fengqiang Li, Zihe Gao, Michael Hall US10902623 , Granted, 2021

Fengqiang Li, Michael Hall US10855896 , Granted, 2020

Fengqiang Li, Michael Hall US10791282 , Granted, 2020

Fengqiang Li, Oliver Cossairt US20200120299A1 , 2020

Fengqiang Li, Michael Hall US10791286 , Granted, 2020

Fengqiang Li, Michael Hall US10630925 , Granted, 2020

Oliver Cossairt, Fengqiang Li, Florian Willomitzer, Prasanna V Rangarajan US20190301857A1 , 2019

Emily Cooper, Fengqiang Li US10277842 , Granted, 2019

Teaching

Teaching Assisant, Introduction to Computational Photography, Northwestern EECS, 2018 Fall


Website credits to Jon Barron