Why Browser Zoom For Low Vision Users

1. SUCKS Why Browser ZoomFor Low Vision Users Denis Boudreau Deque Systems, Inc. db@deque.com @dboudreau Wayne Dick CSU Long Beach waynedick@knowbility.org An <a11yRant/> production.

2. It all started with this.

3. Or rather, this… (200%)

4. Actually, maybe even this… (300%)

5. But more specifically, THIS.

6. No, not THAT KINDof agnosticism, but rather… Thomas Henry Huxley (1869)

8. Leading to heated internal debates Browser Zoom! Text Resize!

9. Why BOTHERwith SC 1.4.4 if it NEVER FAILS!

10. Web Developers vs. End Users

11. What Web Developers Want Easy Solutions Reliable Testing Measurable Results Browser Zoom Web Developers vs. End Users

12. VS. What Web Developers Want Easy Solutions Reliable Testing Measurable Results Browser Zoom What Low VisionUsers Expect Robust Solutions Adaptive Interfaces Usable Content Text Resize Web Developers vs. End Users

13. WHO estimates 285 million visually impaired people worldwide.39 million are blind. 246 have low vision (7.3x as many).

14. As opposed to the United States population…

15. Or even Canada’s!

16. Our job is not to go easy on developers who should know better, but to help foster digital equality for everyone.

17. Browser Zoom Only Testing IS POINTLESSfor HTML Accessibility

18. Browser Zoom Only Testing IS POINTLESSfor HTML Accessibility »»» So what about the end users???

19. Web Developers vs. End Users

20. Visual Concepts • Acuity Limit • Critical Print Size (CPS) • Feasible Print Range • Cost + Technology + • Reader Preference => CPS • To read you need CPS + Word Wrapping

21. Image of graph of reading speed (vertical) by font size (horizontal)… very simplified.

22. Is Zoom bad for Everything? NO! • Zoom is great for spot work near the acuity limit • Small Control forms can be zoomed and operated • Zoom just fails for reading. • The reason follows

23. Why? Enlarged content presented for users with full sight is not the same as content presented for users with compromised sight.

24. Specifically • Lack of word wrapping creates semantic discontinuity • Discontinuity creates data loss and noise • Now let’s quantify the data loss and noise

25. Figure1:A Simple Text Standard Print

26. Figure 2:Same Text Zoomed with NO Reflow

27. Same Text Enlarged WITH Reflow

28. Counting Words • Figure 1: 113 words • Figure 2: 36 words (counting partial words) • Figure 3: 35 words • At a glance, Figure 2 looks as efficient as Figure 3

29. Continuity • Figure 1 (standard print) and Figure 3 (large print wrapped) present contiguous data. • In of the language in the essay the first word of each line is the immediate successor of the last word on the preceding line. • This is true for Figure 1 and Figure 3 even though Figure 1 has 3 times the words. • Even though Figure 3 reduces the quantity of data every word on the page is useful.

30. Discontinuity and Noise • Lines are not connected in Figure 2 (Zoom NO Wrap). • Consider the highlighted line, “Screen magnifier users may.” • The last visible preceding word is truncated “assisti” • Between “assisti” and “Screen” are four words and “ve”, the tail of “assistive”. • This means on line has any real meaning. • The rest are noise

31. Data Loss • In the first and third figure there is no noise. • In Figure 2 (NO Wrap). • Looking at the highlighted line (the signal) we have 4 words • The remainder the disjoint lines, words we have 32 words • Thus only 1 in for words on this view port have meaning as we read the highlighted line. • Figure 3 has 35 words, Figure 2 has 36 but • Every word on the Figure 3 (WITH Wrap) viewport is useful • Only 1/8 are useful in Figure 2 (NO Wrap)

32. The Burning Question? • Is zoom without reflow a functional tool for reading? • Is screen magnification reasonable accommodation? • Does screen magnification constitute accessibility support for WCAG 2.0 criteria?

33. Open Discussion

34. Thinking RWD

35. Web Developers vs. End Users

36. Bake SC 1.4.4 straight into your CSS

37. Thank you! Photo Credits http://gigaom2.files.wordpress.com/2012/08/shutterstock_97220924.jpg http://udemand.files.wordpress.com/2012/07/14.jpg http://taoofman.com/wp-content/uploads/2012/06/ToM_EnsoCircle.png http://www.information.dk/sites/information.dk/files/media/2009/05/01/20090501-174730-pic-363902257.jpg http://www.namespedia.com/image/Huxley_2.jpg http://www.flickr.com/photos/xurble/196294004/ http://free-illustrations-ls01.gatag.net/images/lgi01a201309211700.jpg http://www.flickr.com/photos/kingdesignchile/9023900039/ http://ministry127.com/sites/default/files/Avoiding%20the%20Traps%20of%20the%20Teen%20Years-blank.jpg http://www.sciculture.ac.uk/files/2013/12/Ignite-Event-Image-2.jpg http://www.abortionmemorial.com/wp-content/uploads/2013/07/blurred-vision.jpg