ScanMatch: A novel method for comparing fixation sequences (Cristino et al, 2010)

Using algorithms designed to compare DNA sequence in eye movement comparison. Radical, with MATLAB source code, fantastic! Appears to be noise tolerant and outperform traditional Levenshtein-distance.

Abstract
We present a novel approach to comparing saccadic eye movement sequences based on the Needleman–Wunsch algorithm used in bioinformatics to compare DNA sequences. In the proposed method, the saccade sequence is spatially and temporally binned and then recoded to create a sequence of letters that retains fixation location, time, and order information. The comparison of two letter sequences is made by maximizing the similarity score computed from a substitution matrix that provides the score for all letter pair substitutions and a penalty gap. The substitution matrix provides a meaningful link between each location coded by the individual letters. This link could be distance but could also encode any useful dimension, including perceptual or semantic space. We show, by using synthetic and behavioral data, the benefits of this method over existing methods. The ScanMatch toolbox for MATLAB is freely available online (www.scanmatch.co.uk).

• Filipe Cristino, Sebastiaan Mathôt, Jan Theeuwes, and Iain D. Gilchrist
  ScanMatch: A novel method for comparing fixation sequences
  Behav Res Methods 2010 42:692-700; doi:10.3758/BRM.42.3.692
  Abstract   Full Text (PDF)   References

An improved algorithm for automatic detection of saccades in eye movement data and for calculating saccade parameters (Behrens et al, 2010)

Abstract
"This analysis of time series of eye movements is a saccade-detection algorithm that is based on an earlier algorithm. It achieves substantial improvements by using an adaptive-threshold model instead of fixed thresholds and using the eye-movement acceleration signal. This has four advantages: (1) Adaptive thresholds are calculated automatically from the preceding acceleration data for detecting the beginning of a saccade, and thresholds are modified during the saccade. (2) The monotonicity of the position signal during the saccade, together with the acceleration with respect to the thresholds, is used to reliably determine the end of the saccade. (3) This allows differentiation between saccades following the main-sequence and non-main-sequence saccades. (4) Artifacts of various kinds can be detected and eliminated. The algorithm is demonstrated by applying it to human eye movement data (obtained by EOG) recorded during driving a car. A second demonstration of the algorithm detects microsleep episodes in eye movement data."

• F. Behrens, M. MacKeben, and W. Schröder-Preikschat
  An improved algorithm for automatic detection of saccades in eye movement data and for calculating saccade parameters. Behav Res Methods 2010 42:701-708; doi:10.3758/BRM.42.3.701
  Abstract  Full Text (PDF  References

Gaze Tracker 2.0 Preview

On my 32nd birthday I'd like to celebrate by sharing this video highlighting some of the features in the latest version of the GT2.0 that I've been working on with Javier San Agustin and the GT forum. Open source eye tracking have never looked better. Enjoy!


HD video available (click 360p and select 720p)

Eye Tracking Controlled Audio Sequencer

How to build low cost eye tracking glasses for head mounted system (M. Kowalik, 2010)

Michał Kowalik of the Faculty of Computer Science and Information Technology at the West Pomeranian University of Technology in Szczecin, Poland, has put together a great DIY instruction for a headmounted system using the ITU Gaze Tracker. The camera of choice is the Microsoft LifeCam VX-1000 which has been modified by removing the casing and IR filter. In addition, three IR LEDs illuminate the eye using power from the USB cabel. This is then mounted on a pair of safety glasses, just like Jason Babcock & Jeff Pelz previously have done. Total cost of the hardware less than 50€. Neat. Thanks Michal.

Download instructions as PDF (8.1Mb)

Call for Papers: ACM Transactions Special Issue on Eye Gaze

ACM Transactions on Interactive Intelligent Systems
Special Issue on Eye Gaze in Intelligent Human-Machine Interaction

Aims and Scope

Partly because of the increasing availability of nonintrusive and high-performance eye tracking devices, recent years have seen a growing interest in incorporating human eye gaze in intelligent user interfaces. Eye gaze has been used as a pointing mechanism in direct manipulation interfaces, for example, to assist users with “locked-in syndrome”. It has also been used as a reflection of information needs in web search and as a basis for tailoring information presentation. Detection of joint attention as indicated by eye gaze has been used to facilitate computer-supported human-human communication. In conversational interfaces, eye gaze has been used to improve language understanding and intention recognition. On the output side, eye gaze has been incorporated into the multimodal behavior of embodied conversational agents. Recent work on human-robot interaction has explored eye gaze in incremental language processing, visual scene processing, and conversation engagement and grounding.

This special issue will report on state-of-the-art computational models, systems, and studies that concern eye gaze in intelligent and natural human-machine communication. The nonexhaustive list of topics below indicates the range of appropriate topics; in case of doubt, please contact the guest editors. Papers that focus mainly on eye tracking hardware and software as such will be relevant (only) if they make it clear how the advances reported open up new possibilities for the use of eye gaze in at least one of the ways listed above.

Topics

• Empirical studies of eye gaze in human-human communication that provide new insight into the role of eye gaze and suggest implications for the use of eye gaze in intelligent systems. Examples include new empirical findings concerning eye gaze in human language processing, in human-vision processing, and in conversation management.
  
• Algorithms and systems that incorporate eye gaze for human-computer interaction and human-robot interaction. Examples include gaze-based feedback to information systems; gaze-based attention modeling; exploiting gaze in automated language processing; and controlling the gaze behavior of embodied conversational agents or robots to enable grounding, turn-taking, and engagement.
  
• Applications that demonstrate the value of incorporating eye gaze in practical systems to enable intelligent human-machine communication.

Guest Editors

• Elisabeth André, University of Augsburg, Germany (contact: andre[at]informatik[dot]uni-augsburg.de)
• Joyce Chai, Michigan State University, USA

Important Dates

• By December 15th, 2010: Submission of manuscripts
• By March 23rd, 2011: Notification about decisions on initial submissions
• By June 23rd, 2011: Submission of revised manuscripts
• By August 25th, 2011: Notification about decisions on revised manuscripts
• By September 15th, 2011: Submission of manuscripts with final minor changes
• Starting October, 2011: Publication of the special issue on the TiiS website and subsequently in the ACM Digital Library and as a printed issue

 Source http://tiis.acm.org/special-issues.html

Eye control for PTZ cameras in video surveillance

Bartosz Kunka, a PhD student at the Gdańsk University of Technology have employed a remote gaze-tracking system called Cyber-Eye to control PTZ cameras in video surveillance and video-conference systems. The movie prepared for system presentation on Research Challange at SIGGRAPH 2010 in Los Angeles.

EOG used to play Super Mario

Came across some fun work by Waterloo labs that demos how to use a bunch of electrodes and a custom processing board to do signal analysis and estimate eye movement gestures though measuring EOG. It means you'll have to glance at the roof or floor to issue commands (no gaze point-of-regard estimation). Good thing is that the technology doesn't suffer from issues with light, optics and sensors that often makes video based eye tracking and gaze point-of-regard estimation complex. Bad thing is that it requires custom hardware, mounting of electrodes and wires, besides that the interaction style appears to involve looking away from what you are really interested in.

Eye tracking game concept

Eye tracking game: Summary from theo tveteras on Vimeo.

Video-games can be beneficial!

Appears video-games can be beneficial your your eyes despite what mother said. Came across this article in the British Daily Mail, found it inspiring and believe it could be done even better with an interactive application using real-time gaze tracking input. Direct quote:

"A six-year-old boy who nearly went blind in one eye can now see again after he was told to play on a Nintendo games console. Ben Michaels suffered from amblyopia, or severe lazy eye syndrome in his right eye from the age of four. His vision had decreased gradually in one eye and without treatment his sight loss could have become permanent. His GP referred him to consultant Ken Nischal who prescribed the unusual daily therapy. Ben, from Billericay, Essex, spends two hours a day playing Mario Kart on a Nintendo DS with his twin Jake. Ben wears a patch over his good eye to make his lazy one work harder. The twins' mother, Maxine, 36, said that from being 'nearly blind' in the eye, Ben's vision had 'improved 250 per cent' in the first week. She said: 'When he started he could not identify our faces with his weak eye.  Now he can read with it although he is still a way off where he ought to be. 'He was very cooperative with the patch, it had phenomenal effect and we’re very pleased.' Mr Nischal of Great Ormond Street Children's Hospital, said the therapy helped children with weak eyesight because computer games encourage repetitive eye movement, which trains the eye to focus correctly. 'A games console is something children can relate to. It allows us to deliver treatment quicker,' he said. 'What we don’t know is whether improvement is solely because of improved compliance, ie the child sticks with the patch more, or whether there is a physiological improvement from perceptual visual learning.' The consultant added that thousands of youngsters and adults could benefit from a similar treatment." (source)