Introduction to Eye Tracking

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Introduction to Eye Tracking

Tanja Blascheck

Eurographics Tutorial: Eye Tracking Visualization | 05/04/2015 | Zürich, Schweiz

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 Historical Overview

 Eye Tracking

 Taxonomy

 Terminology

 Stimulus-related Categories

 Visualization-related Categories

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Content

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 11th century - doctor from Egypt: examined eye movements and described them as sequence of fast single movements

 1878 - Emile Javal: eye movements while reading text

 1930 - Miles Tinker and colleagues: reading strategies with different layouts

 1968 - Edmund Huey: book „The psychology of reading“

 1967 – Alfred L. Yarbus: eye movements while looking at a painting

 1970s – Psychology: eye tracking and cognitive processes

 1980s – Eye tracking in human-computer interaction

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Historical Overview

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Historical Overview

[Yarbus 1967]

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 1901 - Dodge und Cline: eye tracker using corneal reflection

 1905 - McAllister und Steel: photography to measure eye movements

 1948- Hartridge und Thompson: first head-mounted eye tracker

 1968 – Huey: contact lense with aluminium pointer

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Historical Overview

[Young 1975]

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 User Study:

 Completion Time

 Accuracy Rate

 Questionnaire

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Eye Tracking - Motivation

Distribution of

Visual Attention? Eye Tracking

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 Data gathering for sensory organs per second

 Eyes: 10 millions bits/sec

 Skin: 1 million bits/sec

 Ears: 100,000 bits/sec

 Nose: 100,000 bits/sec

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Motivation

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Analysis

 Quantitative

 Statistics using significant tests

 Different Metrics

 Fixation Count

 Fixation Duration

 Scanpath Length

 Time to first fixation in AOI

 More se Holmqvist et al.

 Qualitative

 Visualization

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 User Interfaces

 Marketing

 Psychology

 Visualization

 Automobiles

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Applications

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 Different types of eye trackers

 Stationary

 Wearable

 Interactive

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Hardware

Tobii eye X

SMI Glasses

Tobii T60Xl

[http://www.tobii.com/]

[http://www.smivision.com/en.html]

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 Eyesight test

 Color test (Ishihara color charts)

 Calibration (6-9 points)

 Calibration Cross

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Eye Tracking – Study Process

[http://en.wikipedia.org/wiki/Snellen_chart]

[http://en.wikipedia.org/wiki/Ishihara_Test]

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 State-of-the-Art of Visualization for Eye Tracking Data

 STAR Proceedings of EuroVis 2014

 T. Blascheck, K. Kurzhals, M. Raschke, M. Burch, D. Weiskopf, T. Ertl

 http://go.visus.uni-stuttgart.de/

EyeTrackingVisSTAR

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Taxonomy

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Taxonomy

Eye tracking terminology

Stimulus-related

categories Visualization-related categories

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Taxonomy

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Terminology

Stimulus

Gaze Points

Fixation Scanpath

Saccade

Areas of Interest

Gaze

Transition

Eye Tracking Terminology Stimulus-related categories Visualization- related categories

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 Smooth Pursuit

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Terminology

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Taxonomy

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 Point-based

 Focuses on overall movements

 Spatial and temporal distribution

 AOI-based

 Semantic annotation of data

 Transition and relation of AOI

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Stimulus-Related Categories

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 Static Stimulus

 Stimulus does not change

 Static visualization, picture, web page

 Dynamic Stimulus

 Stimulus changes

 Video, real-world scenario,

dynamic visualization, web page

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Stimulus-Related Categories

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 Passive Stimulus Content

 No interfering action

 Static or dynamic stimulus

 Active Stimulus Content

 Active influence of stimulus

 Dynamic stimulus

 Synchronization of participants difficult

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Stimulus-Related Categories

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 2D Stimulus

 Static or dynamic

 2D visualization, video, web page

 3D Stimulus

 Stereoscopic images on 3D screen

 Head-mounted eye tracking

 Mapping of fixations to geometric model is difficult

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Stimulus-Related Categories

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Taxonomy

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 Temporal

 Focuses on time

 Spatial

 Focuses on x-, y-, and z-coordinate of fixations

 Spatio-Temporal

 Combines time and space

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Visualization-Related

Categories

^E^y^e^T^rac

king Terminology Stimulus-related categories Visualization- related categories

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 Static Visualization

 Time-to-space mapping of data

 AOIs for dynamic stimuli

 Animated Visualization

 Time-to-time mapping of data

 Complex layout algorithms

 Aesthetic drawing criteria

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Visualization-Related

Categories

^E^y^e^T^rac

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 Single User

 Viewing behavior of one participant

 Multiple Users

 Strategies of participant group

 Visual clutter possible

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Visualization-Related

Categories

^E^y^e^T^rac

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 2D Visualizations

 Two data types visualized

 3D data: data loss

 3D Visualizations

 3D data: no data loss

 Perceptual issues

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Visualization-Related

Categories

^E^y^e^T^rac

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 In-Context Visualization

 Link stimulus and visualization

 Mental map preservation

 Not In-Context Visualization

 Stimulus not represented

 Topology of AOIs lost

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Visualization-Related

Categories

^E^y^e^T^rac

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 Non-Interactive Visualization

 Fixed set of parameters

 User has no influence

 Interactive Visualization

 Explore data

 Navigate, zoom, filter, …

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Visualization-Related

Categories

^E^y^e^T^rac

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 Visual Analytics

 Algorithmic concepts: data mining, knowledge discovery

 Visualization techniques

 Interaction

 Eye Tracking and Visual Analytics:

 Andrienko et al. 2012

 Ooms et al. 2012

 Kurzhals and Weiskopf 2013

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Visualization-Related

Categories

^E^y^e^T^rac

[Keim et al. 2010]

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 Historical Overview

 Eye Tracking

 Taxonomy

 Terminology

 Stimulus-related Categories

 Visualization-related Categories

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Conclusion

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 T. Blascheck, K. Kurzhals, M. Raschke, M. Burch, D. Weiskopf, T. Ertl:

State-of-the-Art of Visualization for Eye Tracking Data. State-of-the-art reports at EuroVis 2014.

 K. Holmqvist, M. Nyström, R. Andersson, R. Dewhurst, H. Jarodzka, J. van de Weijer. 2011. Eye Tracking. Oxford University Press.

 A.T. Duchowski. Eye Tracking Methodology (2nd. ed.). Springer-Verlag, Berlin Heidelberg New York.

 A. L. Yarbus, Eye Movements and Vision. New York: Plenum Press, 1967

 L. Young, D. Sheena: Survey of eye movement recording methods.

Behavior Research Methods & Instrumentation. Springer-Verlag, 1975.

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Introduction to Eye Tracking