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

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]