About

Welcome to the Video, Image, and Sound Analysis Lab (VISAL) at the City University of Hong Kong! The lab is directed by Dr. Antoni Chan in the Department of Computer Science.

Our main research activities include:

  • Computer Vision, Surveillance
  • Machine Learning, Pattern Recognition
  • Computer Audition, Music Information Retrieval
  • Eye Gaze Analysis

For more information about our current research, please visit the projects and publication pages.

Opportunities for graduate students and research assistants – if you are interested in joining the lab, please check this information.

Latest News [more]

  • [Sep 11, 2020]

    Congratulations to Sergio for defending his thesis!

  • [Nov 28, 2019]

    Congratulations to Weihong for defending his thesis!

  • [Nov 28, 2019]

    Congratulations to Tianyu for defending his thesis!

  • [Aug 23, 2019]

    Xueying Zhan receives the “Outstanding Academic Performance Award”, and Xueying Zhan and Jia Wan receive the “Research Tuition Scholarship” from the School of Graduate Studies. Congratulations!

Recent Publications [more]

Recent Project Pages [more]

Compare and Reweight: Distinctive Image Captioning Using Similar Images Sets

To improve the distinctiveness of image captions, we first propose a metric, between-set CIDEr (CIDErBtw), to evaluate the distinctiveness of a caption with respect to those of similar images, and then propose several new training strategies for image captioning based on the new distinctiveness measure.

ROAM: Recurrently Optimizing Tracking Model

We propose to offline train a recurrent neural optimizer to update a tracking model in a meta-learning setting, which can converge the model in a few gradient steps during online training.

3D Crowd Counting via Multi-View Fusion with 3D Gaussian Kernels

Recently, an end-to-end multi-view crowd counting method called multi-view multi-scale (MVMS) has been proposed, which fuses multiple camera views using a CNN to predict a 2D scene-level density map on the ground-plane. Unlike MVMS, we propose to solve the multi-view crowd counting task through 3D feature fusion with 3D scene-level density maps, instead of the 2D ground-plane ones.

Adaptive Density Map Generation for Crowd Counting

In the sense of end-to-end training, the hand-crafted methods used for generating the density maps may not be optimal for the particular network or dataset used. To address this issue, we propose an adaptive density map generator, which takes the annotation dot map as input, and learns a density map representation for training a counter. The counter and generator are trained jointly within an end-to-end framework.

Eye Movement analysis with Switching HMMs (EMSHMM)

We use a switching hidden Markov model (EMSHMM) approach to analyze eye movement data in cognitive tasks involving cognitive state changes. A high-level state captures a participant’s cognitive state transitions during the task, and eye movement patterns during each high-level state are summarized with a regular HMM.

Recent Datasets and Code [more]

Eye Movement analysis with Switching HMMs (EMSHMM) Toolbox

This is a MATLAB toolbox for analyzing eye movement data using switching hidden Markov models (SHMMs), for analyzing eye movement data in cognitive tasks involving cognitive state changes. It includes code for learning SHMMs for individuals, as well as analyzing the results.

EgoDaily – Egocentric dataset for Hand Disambiguation

Egocentric hand detection dataset with variability on people, activities and places, to simulate daily life situations.

CityStreet: Multi-view crowd counting dataset

Datasets for multi-view crowd counting in wide-area scenes. Includes our CityStreet dataset, as well as the counting and metadata for multi-view counting on PETS2009 and DukeMTMC.

CityUHK-X: crowd dataset with extrinsic camera parameters

Crowd counting dataset of indoor/outdoor scenes with extrinsic camera parameters (camera angle and height), for use as side information.

DPHEM toolbox for simplifying GMMs

Toolboxes for density-preserving HEM algorithm for simplifying mixture models.