Current Research Projects
Attention Modeling and Tracking
- Modeling the task dependence of attention
- Modeling attention in viewing cellphone displays
- Increasing information transfer in cellphones by linking perception and action
- Applying attention tracking to modulating video game difficulty.
- Studying the link between microsaccades and visual attention.
- Examining microsaccades during pursuit eye movements.
Haji-Abolhassani, A. and Clark, J.J., ``Realization of an Inverse Yarbus Process via Hidden Markov Models for Visual-Task Inference'', accepted for presentation at the 2011 Vision Science Symposium (VSS).
Ziat, M., Au, C.E., Haji-Abolhassani, A. and Clark, J.J., ``Engaging Attention through Action in Map Learning on Cell Phones'', accepted for publication in ACM Transactions on Applied Perception
Jie, L. and Clark, J.J., ``Video Game Design Using an Eye Movement Dependent Model of Visual Attention'', ACM Transactions on Multimedia Computing, Communications, and Applications, Vol. 4, No. 3, pp 22:1-16, 2008.
Jie, L. and Clark, J.J., ``Game Design Guided by Visual Attention", Proceedings of the International Conference on Entertainment Computing, Springer Lecture Notes in Computer Science, pp 345-355, Shanghai, September 2007
Clark, J.J., Hafed, Z. and Jie, L. ``Attention and Action'', in Computational Vision in Neural and Machine Systems, L. Harris and M. Jenkin, eds., Cambridge University Press, Cambridge England, 2007
Jie, L. and Clark, J.J., "Microsaccadic Eye Movements During Ocular Pursuit", Vision Sciences Society Annual Meeting (VSS), Sarasota, Florida, May 2005, abstract published in Journal of Vision, Volume 5, Number 8, Page 697a, 2005.
Hafed, Z.M. and Clark, J.J., ``Detecting patterns of covert attention shifts in psychophysical tasks using microsaccades'', Vision Sciences Society Annual Meeting (VSS), Sarasota, Florida, May 2003. also in Journal of Vision3(9), 183a.
Hafed, Z.M. and Clark, J.J., ``Microsaccades as an overt measure of covert attention shifts", Vision Research, Vol. 42, No. 22, pp 2533-2545, 2002.
Hafed, Z. and Clark, J.J., ``Pre-saccade target color influences the perception of its post-saccade counterpart", 2002 Vision Sciences Society Annual Meeting (VSS), Sarasota, Florida, p. 65, May 2002. (also in Journal of Vision, Vol. 2, No. 7, p. 175a.)
Augmented Reality and Video Surveillance
- Integration of multiple views using virtual mirroring.
- Detection of anomalies based on comparison to stored exemplars.
- Multiple camera implementation of person detection.
- FPGA hardware implementation of person detection.
- Unsupervised online learning technique for moving person detection.
- Hidden-Markov-Model approach to detecting anomalous person trajectories.
Demirkus, M., Oreshkin, B., Clark, J.J. and Arbel, T., ``Spatial and probabilistic codebook template based head pose estimation from unconstrained environments'', accepted for presentation at the IEEE International Conference on Image Processing (ICIP), Brussels, September 2011
Au, C.E. and Clark, J.J., ``Integrating Multiple Views with Virtual Mirrors to Facilitate Scene Understanding'', accepted for publication in ACM Transactions on Applied Perception
Demirkus, M., Toews, M., Clark, J.J. and Arbel, T., ``Gender Classification from Unconstrained Video Sequences'', IEEE Workshop on Analysis and Modeling of Faces and Gestures (AMFG), San Francisco, June 2010
Au, C.E. and Clark, J.J., ``Multiple View Integration and Display Using Virtual Mirrors", the 5th Canadian Conference on Computer and Robot Vision, Windsor, Ontario, May 2008.
Au, C.E., Skaff, S., and Clark, J.J., "Anomaly Detection for Video Surveillance Applications", in Proceedings of the 18th IEEE International Conference on Pattern Recognition, Vol. 4, p.p. 888-891, Hong Kong, Aug. 20-24, 2006.
Ahmedali, T. and Clark, J.J., "Collaborative Multi-Camera Surveillance with Automated Person Detection", Proceedings of the 2006 International Workshop on Video Processing for Security, p. 39, Quebec City, June 2006.
Nair, V., Laprise, P.-O., and Clark, J.J., "An FPGA-based people detection system", EURASIP Journal on Applied Signal Processing, Vol. 7, pp 1047-1061, 2005.
Nair, V. and Clark, J.J., "An unsupervised, online learning framework for moving objec t detection", 2004 IEEE Conference on Computer Vision and Pattern Recognition, Washington D.C., Vol. 2, pp 317-324, June 2004.
Nair, V. and Clark, J.J., ``Automated Visual Surveillance Using Hidden Markov Models", the 15th Vision Interface Conference, Calgary, pp 88-92, May 2002.
Spectral Modeling and Color Vision
- Color perception as spectral modeling.
- Maximum entropy spectral modeling.
- Interpreting interreflections with spectral models.
- Spectral models for underwater color imaging.
- Integrating multiple views from a nonuniform color sensor.
Clark, J.J. and Skaff, S., "A spectral theory of color perception", Journal of the Optical Society of America - A, Vol. 26, No. 12, pp. 2488-2502, 2009.
Skaff, S., Arbel, T., and Clark, J.J., "A Sequential Bayesian Approach to Color Constancy using Non-Uniform Filters", Computer Vision and Image Understanding, Vol. 113, No. 9, pp. 993-1004, 2009.
Skaff, S. and Clark, J.J., ``Maximum Entropy Spectral Models for Color Constancy in the Presence of Interreflections," Proceedings of the 16th Color Imaging Conference, Portland, OR, November 2008.
Skaff, S., Clark, J.J., and Rekleitis, I. ``Estimating Surface Reflectance Spectra for Underwater Color Vision" Proceedings of the 2008 British Machine Vision Conference, Leeds, U.K., Vol. 2, pp. 1015-1024, September 2008.
Skaff, S. and Clark, J.J., ``Maximum Entropy Spectral Models for Color Constancy", Proceedings of the 15th Color Imaging Conference, Albuquerque, N.M., pp. 100-105, November 2007.
Clark, J. and Skaff, S., "Maximum Entropy Models of Surface Reflectance Spectra", Instrumentation and Measurement Technology Conference (IMTC), Ottawa, Ontario, Vol. 2, pp 1557-1560, May 2005
Skaff, S., Arbel, T., and Clark, J.J., ``Active Bayesian Color Constancy with Non-Uniform Sensors'', International Conference on Pattern Recognition, Quebec City, Canada, pp II-681:684, August 2002.
Sensorimotor Theories of Perception
- Sensorimotor theories of color perception.
- Perceptual stability and the learning of invariance.
- Entropy of spatio-temporal surrounds and intensity perception.
- Eye movements and the perception of space.
Reeve, P., Clark, J.J. and O'Regan, J.K., "Convergent flash localization near saccades without equivalent 'compression' of perceptual separation", Journal of Vision, Vol. 8(13):5, pp. 1-19, 2008
Li, M. and Clark, J.J., "A Temporal Stability Approach to Position and Attention Shift Invariant Recognition", Neural Computation, Vol. 16, No. 11, pp 2293 - 2321, 2004.
Reeve, P., Clark, J.J. and O'Regan, J.K, "Perceptual visual space is not compressed before saccades", 2004 European Conference on Visual Perception, Budapest, Hungary, August 2004
Clark, J.J., ``Ecological considerations support color physicalism'', commentary in Behavioural and Brain Sciences, Vol 26, pp 24-25, 2003.
Clark, J.J. and Hernandez, D., ``Surround statistics and the perception of intensity and color'', 3rd International Workshop on Statistical and Computational Theories of Vision, Nice, October 2003.
Bompas, A., Clark, J.J. and O'Regan, J.K., "Color Perception in the Sensorimotor Contingency Theory", European Conference on Visual Perception, Scotland, August 2002.
Clark, J.J. and O'Regan, J.K., ``A Temporal-difference learning model for perceptual stability in color vision'', 2000 International Conference on Pattern Recognition, Barcelona, Spain, September 2000, pp 503-506.
