1. Counting How Many Words You Read

2. Reading Habit Quantifying reading habit
Provides insights on language skills, effective learning and critical thinking
Identifying a reading log, time spent on reading at different time of day may provide these insights
Electrooculography and optical eye tracking provide the opportunity to track reading

3. Motivational Applications
Quantifying reading habit
Might help to identify the children with reading disabilities
People can increase their reading speed without any problem
Quantifying self

4. Contributions
Quantifying how much words a user reads working for both optical eye tracking and electrooculography
Lowest error rate between 5 – 15% for word count estimation
Initial hint that these method can work with commercial smart glasses

5. Fixation
Fixation or visual fixation is the maintaining of the visual gaze on a single location

6. Saccade Saccade Alternate saccades and visual fixations,
quick, simultaneous movement of both eyes between two phases of fixation in the same direction
can be associated with a shift in frequency of an emitted signal or a movement of a body part or device
Alternate saccades and visual fixations,

7. Eye Tracking Electrooculography Uses electrodes
Measures change in potential when eye moves as eye is considered as a diphole between cornea and retina
Cheap, but gives relative eye movements

8. Eye Tracking Optical Tracking
Uses cameras and infrared light to track eye gaze
Binocular gaze estimates at a sampling freq. 30Hz
Video resolution with resolution 1280X960 pixel
Provides higher accuracy but requires high power to infer eye position, motion and gaze based on iris shape
Provides raw eye gaze data
(Saccade and fixation data)

9. Proposed Approach

10. Proposed Approach Preprocessing Reading detection Line-break detection
Word count estimation

11. Preprocessing Optical tracking
Combines several close by fixations into larger duration fixation

12. Reading Detection Calculate these features in 3 sec framing window
Apply a SVM classifier
For EOG, blink duration and frequency is also used as a feature
For optical system mean fixation duration and variance of fixation count is used

13. Line-break Detection Reading is dominated by two types of saccades
Detection of the dynamic line breaks using the distribution of the horizontal component of saccade
Reading is dominated by two types of saccades
short one in reading direction
Longer saccade against the reading
Two steps
Combine consecutive saccade against reading direction
Horizontal Saccade Direction (HSD) histogram

14. Line-break Detection Dynamic line break detection Saccade amplitude sa
Horizontal direction component sdh
-1 for the against main reading and +1 for the in reading
Horizontal saccade direction component
HSD = sa * sdh
HSD distribution is noted next

15. Line-break Detection
Combine all saccades, calculate HSD and combine them in HSD histogram
Fit a mixture of 2 Gaussians and take distance between two maximas

16. Line-break Detection Two types of saccades
Short
Long
larger one is the average reading saccade direction * amplitude
Second maximum average line break saccade direction

17. Line-break Detection Two steps
Combine consecutive saccade against reading direction

18. Determine line break

19. Word Count Estimation Basic Word Count
(1)Avg. word count from the document read time
(2) Estimate from line breaks
Uses the information – avg. words per line
Words per line – easy for electronic system
For paper image retrieval technique

20. Word Count Estimation Basic Word Count SVR count
(1)Avg. word count from the document read time
(2) Estimate from line breaks
Uses the information – avg. words per line
Words per line – easy for electronic system
For paper- image retrieval technique
SVR count
Uses features
total time read,
sum of all saccades distance,
sum of the line break saccade distances,
number of line breaks and
sum of the reading saccade distances
Train a SV regression

21. Experimental Setup Mobile optical eye tracking Mobile eye tracker 2.0
Binocular gaze estimates at a sampling freq. 30Hz
Video resolution with resolution 1280X960 pixel
Can capture saccades of 33 ms or slower

22. Experimental Setup Baseline Experiment Eye tracking glass
Office scenario, 9 subjects
14 documents to read
10 simple text (PET) , 4 difficult (SAT)
Word length 135 to 414 (mean 245)
Eye gaze and scene camera are recorded
Comprehensive questions
Text understanding

23. Experimental Setup Devices Experiment
Impact of device type and document length on word count accuracy
5 documents of different length read on different devices (size)– paper, smartphone, computer screen, tablet---same font 12
Varying line length
Office scenario, 10 subjects
5 documents to read
Word length 135 to 414 (mean 245)
Perform other activities (solving sudoku, talking, playing games)

25. Experimental Setup Electrooculography 8 participants Active electrodes
Sampling rate 1kHz

26. Results – Optical Tracking
Evaluation- Leave one out (of n users)
Reading detection is accurate
Line break detection
HSD Histogram for line break detection on different devices
For baseline dataset, line break method reduces error from 15% to 6%
Device dataset – 62% to 8%

27. Results – Optical Tracking
Word-count estimation
Change in line length
Line break
Reading from the devices is challenging – high error

28. Results – EOG Line break and Word-count estimation
EOG performs better than Mobile tracker

29. Commercial eyewear – JINS MEME
4 participants, 3 days

30. Application