Xiaochen Liu

Xiaochen Liu


I received my Ph.D. in Computer Science, advised by Prof. Ramesh Govindan. My research focuses on efficient video analytics pipelines, positioning and tracking algorithms, and edge computing. I earned my B.S from Peking University before joining NSL. I am currently working at Facebook as a Research Scientist.

[LinkedIn] [Google Scholar] [My Thesis]



  • Yitao Hu, Weiwu Pang, Xiaochen Liu, Rajrup Ghosh, Bongjun Ko, Wei-Han Lee, Ramesh Govindan. Rim: Offloading Inference to the Edge. The 6th ACM/IEEE Conference on Internet of Things Design and Implementation (IOTDI ’21), 2021. [Paper]
  • Xiaochen Liu, Pradipta Ghosh, Oytun Ulutan, B.S. Manjunath, Kevin Chan, Ramesh Govindan. Caesar: Cross-camera Complex Activity Recognition. The 17th ACM Conference on Embedded Networked Sensor Systems (SenSys ’19), 2019. [Paper][Code][Slides][Video]
  • Pradipta Ghosh, Xiaochen Liu, Hang Qiu, Marcos A. M. Vieira, Gaurav S. Sukhatme, Ramesh Govindan. On Localizing a Camera from a Single Image. arXiv preprint arXiv:2003.10664. [Paper][Project]
  • Xiaochen Liu, Yurong Jiang, Kyu-Han Kim, Ramesh Govindan. Grab: Fast and Accurate Sensor Processing for Cashier-Free Shopping. ArXiv Preprints. [Paper][Demo]
  • Xiaochen Liu, Suman Nath, Ramesh Govindan. Gnome: A Practical Approach to NLOS Mitigation for GPS Positioning in Smartphones. The 16th ACM International Conference on Mobile Systems, Applications, and Services (MobiSys), 2018. [Paper][Poster][Slides]
  • Xiaochen Liu, Yurong Jiang, Puneet Jain, Kyu-Han Kim. TAR – Enabling Fine Grained Targeted Advertising in Retail Stores. The 16th ACM International Conference on Mobile Systems, Applications, and Services (MobiSys), 2018. [Paper][DemoA/DemoB][Slides]
  • Fawad Ahmad, Hang Qiu, Xiaochen Liu, Fan Bai, Ramesh Govindan. QuickSketch: Building 3D Representations of Unknown Environments using Crowdsourcing. Proceedings of the 21st International Conference on Information Fusion (Fusion 2018), 2018. [Paper]
  • Hang Qiu, Xiaochen Liu, Swati Rallapalli, Archith J. Bency, Rahul Urgaonkar, B.S. Manjunath, Ramesh Govindan, Kevin Chan. Kestrel: Video Analytics for Augmented Multi-Camera Vehicle Tracking. The Proceedings of ACM/IEEE International Conference on Internet-of-Things Design and Implementation (IoTDI), 2018. [Paper][Demo]
  • Wei-Han Lee, Xiaochen Liu, Yilin Shen, Hongxia Jin, Ruby Lee. Secure Pick Up: Implicit Authentication When You Start Using the Smartphone. The ACM Symposium on Access Control Models and Technologies (SACMAT), 2017. [Paper]
  • Yitao Hu, Xiaochen Liu (co-first author), Suman Nath, Ramesh Govindan. ALPS: Accurate and Complete Landmark Positioning at City Scales. The ACM International Joint Conference on Pervasive and Ubiquitous Computing (UbiComp), 2016. [Paper][Code]
  • Shaohan Hu, Shuochao Yao, Haiming Jin, Yiran Zhao, Yitao Hu, Xiaochen Liu, Nooreddin Naghibolhosseini, Shen Li, Akash Kapoor, William Dron, Lu Su, Amotz Bar-Noy, Pedro Szekely, Ramesh Govindan, Reginald Hobbs, Tarek F. Abdelzaher. Data Acquisition for Real-Time Decision-Making under Freshness Constraints. The IEEE Real-Time Systems Symposium (RTSS), 2015. [Paper]
  • Yang Tian, Kaigui Bian, Guobin Shen, Xiaochen Liu, Xiaoguang Li, Thomas Moscibroda. Contextual-Code: Simplifying Information Pulling from Targeted Sources in Physical World. IEEE Conference on Computer Communications (INFOCOM), 2015. [Paper]

Professional Experience

  • Facebook, Menlo Park, CA, Research Scientist, 2020 – Now
  • Facebook, Boston, MA, Software Engineer Intern, 2019
  • HP Labs, Palo Alto, CA, Intern Researcher, 2017
  • Samsung Research, Mountain View, CA, Intern Researcher, 2015
  • Microsoft Research, Beijing, China, Intern Researcher, 2013



Email: liu851[at]usc[dot]edu

University of Southern California
Department of Computer Science
941 Bloom Walk, SAL 227
Los Angeles, CA 90089-0781