1. TAUCHI – Tampere Unit for Computer-Human Interaction Visualizing gaze path for analysis Oleg Špakov MUMIN workshop 2002, Tampere

2. TAUCHI – Tampere Unit for Computer-Human Interaction Content Introduction (6 pages) Visualizing method (8 pages) Interaction method (8 pages) Conclusions (2 pages) 1

3. TAUCHI – Tampere Unit for Computer-Human Interaction 1.1 Goals Develop the gaze-capturing and gaze-visualizing system for further development as a template Write components (drivers) for system-device communication and database creation Visualize gaze-path as a set of interactive objects Create an environment to run experiment tasks Write some common tasks I. Introduction 2

4. TAUCHI – Tampere Unit for Computer-Human Interaction 1.2 Gaze path It is a collection of instantaneous dots on 2D surface All of them constrain 3 different objects: fixations, saccades and smooth pursuit Could be interrupted by blink Usually measured in degrees according to basic spot (0,0), which is a normal vertex to face flat Huge amount of data needs to be analyzed 3

5. TAUCHI – Tampere Unit for Computer-Human Interaction 1.3 Fixations Fixation is A part of gaze path, where an eye didn’t make big movements and there are no jumps Obtained as an average of X and Y coordinates of constituents dots Also it is a part of gaze path, where an eye made very small movements (directed or not). The size of the movement is conventional. 4

6. TAUCHI – Tampere Unit for Computer-Human Interaction 1.4 Saccades Saccade is a fast eye movement Saccades could be purposive (usually long) and involuntary (short and frequent) Saccades of the second type usually are automatically filtered by gaze-capturing devices Details of captured (by eyes) visual image are unavailable during saccade 5

7. TAUCHI – Tampere Unit for Computer-Human Interaction 1.5 Smooth pursuit Smooth pursuit is a slow eye movement, when the gaze velocity is higher than for fixation, and lower than for saccade. Velocity always waves, and smooth pursuit often interrupted by correlating saccades Relatively hard to recognize 6

8. TAUCHI – Tampere Unit for Computer-Human Interaction 1.6 Blinks Always generate 2 saccades – down at the beginning and up at the end Usually interrupts fixation There no data from gaze-capturing device during blink – the position of eye is unavailable 7

9. TAUCHI – Tampere Unit for Computer-Human Interaction II. Visualization methods Always contains timestamp and gaze projection position (X,Y) to the screen Can contain pupil size of eye(s) Can contain head-tracking data Can contain data for both eyes 2.1 Gaze path data 8

10. TAUCHI – Tampere Unit for Computer-Human Interaction 2.2 Main visualization method All data presents in fixations and saccades, which are visible interactive objects Blinks are the property of saccades All fixations and saccades distributed on the 2D surface Every fixation and saccade object visualize its properties 9

11. TAUCHI – Tampere Unit for Computer-Human Interaction 2.2 Main visualization method Fixation is the circle with properties: Radius Border width Border color Background color Central spot size Saccade is the line with properties: Width Color 10

12. TAUCHI – Tampere Unit for Computer-Human Interaction Visualized data for both fixations and saccades Duration Time Average pupil size Visualized data for saccades only: Blinks number 2.2 Main visualization method 11

13. TAUCHI – Tampere Unit for Computer-Human Interaction 2.2 Main visualization method Duration > RadiusDuration > Border Color Duration > Back-Color 12 Duration > Line width

14. TAUCHI – Tampere Unit for Computer-Human Interaction 2.3 Data over background Allow to overview the observed image parts Allow to makes links between images and gaze 13

15. TAUCHI – Tampere Unit for Computer-Human Interaction 2.4 Data as a clipping region Shows only the observed part of image Calculates rates of observation time 14

16. TAUCHI – Tampere Unit for Computer-Human Interaction 2.5 Samples’ visualization Many samples for every object requires a lot of resources Only samples of 1 currently active fixation or/and saccade are visualized 15

17. TAUCHI – Tampere Unit for Computer-Human Interaction 3.1 Navigation Visible Interactive Adaptive Directed Through fixations, saccades and its samples III. Interaction methods 16

18. TAUCHI – Tampere Unit for Computer-Human Interaction 3.2 Selection Different criterions Interactive Visible Different selection modes 17

19. TAUCHI – Tampere Unit for Computer-Human Interaction 18 3.2 Selection

20. TAUCHI – Tampere Unit for Computer-Human Interaction 3.2 Selection 19

21. TAUCHI – Tampere Unit for Computer-Human Interaction 3.2 Selection 20

22. TAUCHI – Tampere Unit for Computer-Human Interaction 21 3.2 Selection

23. TAUCHI – Tampere Unit for Computer-Human Interaction 3.3 Data obtaining Application allows to get object- and raw-data of any fixation, saccade and blink to get object- and raw-data of any selection of fixations to save any object- and raw-data in a file to load and save any selection range 22

24. TAUCHI – Tampere Unit for Computer-Human Interaction 3.4 Additional features Image loading to background Zooming and panning of visible layout Full-screen mode User-task implementation interface 23

25. TAUCHI – Tampere Unit for Computer-Human Interaction 4.1 Conclusions Different kinds of gaze path visualization were developed Different tools for navigation and selection were developed Visualization parameters are adjustable by user Researchers can use it as a tool to analyze gaze path Also can be used as a template for further development and user tasks creation Some user tasks were created 24

26. TAUCHI – Tampere Unit for Computer-Human Interaction 4.2 Future steps Improve time-position-time navigation Add extra features to events objects Create 3D navigation Movie on the background 25

27. TAUCHI – Tampere Unit for Computer-Human Interaction Thank you for attention Everyone is inviting to take part in development, consulting and testing oleg@cs.uta.fi http://www.cs.uta.fi/~oleg