Prof. Antoni B. Chan

Prof. Antoni B. Chan
Professor, Dept. of Computer Science
Associate Dean (Research & Postgraduate), College of Computing
Deputy Director, Multimedia Engineering Research Centre (MERC)
BSc MEng Cornell, PhD UC San Diego
SrMIEEE

Video, Image, and Sound Analysis Lab (VISAL)
Department of Computer Science
College of Computing
City University of Hong Kong

Office: Room AC1-G7311, Yeung Kin Man Academic Building (lift 7)
Phone: +852 3442 6509
Fax: +852 3442 0503
Email: abchan at cityu dot edu dot hk

News

  • Research Assistant and Technical Assistant positions are available for a project on using ChatGPT in teaching. Details here.

Bio

Dr. Antoni Chan is a Professor at the City University of Hong Kong in the Department of Computer Science.  Before joining CityU, he was a postdoctoral researcher in the Department of Electrical and Computer Engineering at the University of California, San Diego (UC San Diego).  He received the Ph.D. degree from UC San Diego in 2008 studying in the Statistical and Visual Computing Lab (SVCL). He received the B.Sc. and M.Eng. in Electrical Engineering from Cornell University in 2000 and 2001. From 2001 to 2003, he was a Visiting Scientist in the Computer Vision and Image Analysis lab at Cornell. In 2005, he was a summer intern at Google in New York City. In 2012, he was the recipient of an Early Career Award from the Research Grants Council of the Hong Kong SAR, China.

Research Interests [more]

Computer Vision, Surveillance, Machine Learning, Explainable AI (XAI), Pattern Recognition, Computer Audition, Music Information Retrieval, Eye Gaze Analysis

image captioning, object tracking, dynamic textures, motion segmentation, motion analysis, semantic image annotation, image retrieval, crowd counting, probabilistic graphical models, support vector machines, Bayesian regression, Gaussian processes, semantic music annotation and retrieval, music segmentation, feature extraction.

  • For more information about my current research projects, please visit my lab website.
  • Opportunities for graduate students and research assistants! If you are interested in joining the lab, please check this information. Outstanding non-HK students may also consider applying for the HK PhD fellowship.

Recent Publications [more]

Selected Publications [more]

Google Scholar Google Scholar
Microsoft Academic Microsoft Academic
ORCID orcid.org/0000-0002-2886-2513
Scopus ID: 14015159100

Recent Project Pages [more]

Continual Learning MIL

We pinpoint catastrophic forgetting to the attention layers of attention-MIL models for whole-slide images and introduce two remedies: Attention Knowledge Distillation (AKD) to retain attention weights across tasks and a Pseudo-Bag Memory Pool (PMP) that keeps only the most informative patches. Combined, AKD and PMP achieve state-of-the-art continual-learning accuracy while sharply cutting memory usage on diverse WSI datasets.

Image Editing with Diffusion Model from Frequency Perspective

We introduce a novel fine-tuning free approach that employs progressive Frequency truncation to refine the guidance of Diffusion models for universal editing tasks (FreeDiff).

DistinctAD: Distinctive Audio Description Generation in Contexts

We propose a two-stage framework DistinctAD for automatically generating audio descriptions in movies or tv series. DistinctAD targets at generating distinctive and interesting ADs in similar contextual video clips.

P2R Loss for Semi-Supervised Counting

We introduce a Point-to-Region (P2R) loss to address the over-activation and pseudo-label propagation issues inherent in semi-supervised crowd counting. By replacing pixel-level matching with region-level supervision, P2R suppresses background noise and achieves state-of-the-art results with significantly higher training stability.

Proximal Mapping Loss for Crowd Counting

We propose the Proximal Mapping Loss (PML), a theoretically grounded framework that discards the unrealistic “non-overlap” assumption common in crowd counting. By leveraging proximal operators from convex optimization, PML accurately recovers density in highly congested scenes where severe occlusions and overlapping objects are prevalent.

Recent Datasets and Code [more]

Modeling Eye Movements with Deep Neural Networks and Hidden Markov Models (DNN+HMM)

This is the toolbox for modeling eye movements and feature learning with deep neural networks and hidden Markov models (DNN+HMM).

Dolphin-14k: Chinese White Dolphin detection dataset

A dataset consisting of  Chinese White Dolphin (CWD) and distractors for detection tasks.

Crowd counting: Zero-shot cross-domain counting

Generalized loss function for crowd counting.

CVCS: Cross-View Cross-Scene Multi-View Crowd Counting Dataset

Synthetic dataset for cross-view cross-scene multi-view counting. The dataset contains 31 scenes, each with about ~100 camera views. For each scene, we capture 100 multi-view images of crowds.

Crowd counting: Generalized loss function

Generalized loss function for crowd counting.

Teaching

  • CS 5495 – Explainable AI — 2025A.
  • CS 5487 – Machine Learning: Principles & Practice (postgraduate) — 2012A-2026B.
  • CS 5489 – Machine Learning: Algorithms & Applications (postgraduate) — 2020B-2025B.
  • GE1361 – Digital Literacy: New Technologies, Society, and You — 2025B-2026B.
  • CS 6487 – Topics in Machine Learning (postgraduate) — 2019B.
  • CS 4487 – Machine Learning (undergraduate) — 2015A-2018A.
  • GE 2326 – Probability in Action: From the Unfinished Game to the Modern World — 2015B-2017B.
  • GE 1319 – Interdisciplinary Research for Smart Professionals — 2013B-2017B.
  • CS 5301 – Computer Programming — 2012A-2014A.
  • CS 2363 – Computer Programming — 2009A-2011A.
  • CS 3306 (B) – Contemporary Programming Methods in Java — 2010B.
  • CS 4380 (B) – Web 2.0 Technologies — 2011B, 2012B.
  • Multimedia Subject Group leader
  • Research Mentoring Scheme Coordinator
  • Final Year Project Coordinator (2016-2022)
  • MSCS Project and Guided Study Coordinator (2016-2022)
  • BScCM Deputy Programme Leader (2020-2022)

Service

  • Associate Editor, IEEE Transactions on Pattern Analysis and Machine Intelligence (2023-now)
  • Action Editor, Transactions on Machine Learning Research (2022-now)
  • Guest Editor, Special Issue on “Applications of artificial intelligence, computer vision, physics and econometrics modelling methods in pedestrian traffic modelling and crowd safety”, Transportation Research Part C: Emerging Technologies (2022-23)
  • Senior Area Editor, IEEE Signal Processing Letters (2016-2020)
  • Associate Editor, IEEE Signal Processing Letters (2014-2016)
  • Conference Area Chair
    • CVPR – 2020, 2023, 2026
    • ICCV – 2015, 2017, 2019, 2021, 2025 (Lead AC)
    • ECCV – 2022, 2024, 2026
    • NeurIPS – 2020, 2021, 2022, 2023, 2024, 2025 (top 10%)
    • ICML – 2021, 2022, 2023, 2024, 2025, 2026
    • ICLR – 2021, 2023, 2024, 2025, 2026
    • ICPR – 2020
    • Pacific Graphics – 2018
  • Conference Senior PC
    • AAAI – 2021, 2022
    • IJCAI – 2019-20
  • Conference Program Committees
    • CVPR – 2012-2019, 2021, 2022, 2024, 2025
    • ICCV – 2011, 2013, 2023
    • ECCV – 2012, 2014, 2016, 2018
    • ACCV – 2011, 2014, 2016
    • ICML – 2012, 2013, 2014, 2015, 2018, 2019, 2020
    • NIPS – 2015, 2017, 2018, 2019
    • ICLR – 2022
    • Siggraph (tertiary)- 2018
  • Journal Reviewing
    • IEEE Trans. on Pattern Analysis and Machine Intelligence (TPAMI)
    • IEEE Trans. on Image Processing (TIP)
    • Intl. Journal Computer Vision (IJCV)
    • IEEE Trans. on Circuits and Systems for Video Technology (TCSVT)
    • IEEE Trans. on Neural Networks (TNN)
    • IEEE Trans. on Multimedia
    • IEEE Trans. Intelligent Transportation Systems
  • Grant Reviewing
    • A*STAR-JST
  • Organized Events
    • CogSci 2022 Hong Kong Meetup & Symposium: Computational Approaches to Psychological Research, Aug 2022.

Awards and Honors

  • Top 2% Most Highly Cited Researchers (Ioannidis et al. 2019. Plos Biology)
  • The President’s Award, City University of Hong Kong, 2016.
  • Early Career Award, Research Grants Council of Hong Kong, 2012.
  • NSF IGERT Fellowship: Vision and Learning in Humans and Machines, UCSD, 2006-07.
  • Outstanding Teaching Assistant Award, ECE Department, UCSD, 2005-06.
  • Office of the President Award, UCSD, 2003.
  • Henry G. White Scholorship, Cornell University, 2001.
  • Knauss M. Engineering Scholorship, Cornell University, 2001.
  • GTE Fellowship, Cornell University, 2001.
Mailing Address:

Prof. Antoni Chan,
Department of Computer Science,
City University of Hong Kong,
Tat Chee Avenue,
Kowloon Tong, Hong Kong.

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