Development of Accessible E-documents and Programs for the Visually Impaired

1. Development of Accessible E-documents and Programs for the Visually Impaired Accessibility in electronic documents (V2010)

2. 1. Frequently used formats • Online and offline HTML documents • Text documents (DOC, RTF, ODT, TXT...) • PDF documents

3. 2. Text documents (format) • Use sans-serif fonts (Tahoma, Verdana, Arial...) • Use standard font sizes • Italic and capitals are hard to read for visually impaired users • Use contrast colours • In multi-column documents separate columns clearly

4. 3. Tables • Complex tables are hard to read • Split them if possible • Or provide text description • Uniform tables are easier to read • Use merging only if necessary • Do not use nested tables if possible

5. 4. Correct table

6. 5. Incorrect table

7. 6. Document structure • Make headings visually different (do not use only indentation) • Use styles (in Ms Word, Oo Writer...) • Mark them somehow (useful, e.g. in plaintext documents) • Use all structure elements provided by editor / environment (bullets...)

8. 7. MS Word forms • Protected forms are often used • Standard text in protected forms is inaccessible • Screen reader reads only "text on same line" or immediately above the field • Use "status line" text or "help" text to provide long description of form fields

9. 9. PDF documents • Supported by more and more screen readers • Served in special environment (same as web pages) • Document must contain textual information (not "scanned" pictures) • Input fields must be labeled and logical order must be defined • Document must be tagged

10. 10. PDF documents (2) • Reading order must be defined (heading is before the text...) • Provide descriptive text to images, links, form fields • Provide skip links if necessary • Define language in multi-language documents

11. 11. PDF documents (3) • Do not be very restrictive in security settings • use "Enable Text Access For Screen Reader Devices For The Visually Impaired" to give access for screen readers

12. 12. How to prepare accessible PDF • Create correctly structured document (e.g. in OO Writer or MS Word) • Use styles to define headings, provide alternative texts to graphics... • Use Adobe Acrobat to convert file to PDF and tag the file • Open Office 3.0 supports PDF tagging

13. 13. Describing graphs • Graphs in documents must be somehow described • Description depends on graph type • Some examples follow

14. 14. Simple graph

15. 15. Description • Picture: Graphs with oriented edges. ´i -> j represents edge from vertex i to j. • First graph 1 -> 5, 2 ->5, 5 -> 6, 3 -> 6, 4 -> 6, 6 -> 8, 7 -> 8, 8 -> 8, • Second graph 9 -> 10, 10 -> 11, 11 -> 12, 12 -> 13, 13 -> 13. • Each edge should be on separate line

16. 16. Convex polygon

17. 17. Description • Picture: there is closed convex polygon on the picture. Vertices are named V1 to V8. Vertices are ordered clockwise , v1 is leftmost (´on nine). There is a set of points inside the polygon.

18. 18. 2 arrays

19. 19. Description • two arrays, B and A. Array B is splitted to blocks B0, B1, ..., Bi,. B0 contains elements b1 to blog m, B1 contains elements b(log m) + 1 to b2 * log m. in general block Bi contains elements bi * log m + 1 to b(i + 1) * log m. Array A is splitted to blocks A0, A1, ..., Ai. A0 contains elements a1 to aj1, A1 has elements aj(1) + 1 to aj(2). In general Ai. has elements aj(1) + 1 to aj(i + 1). There are arrows from blocks B(i) to A(i).

20. 20. RBT

21. 21. Description • R-B tree: • A: 11 (black); B, C • B: 2 (red); D, E • C: 14 (black); F(right) • D: 1 (black); • E: 7 (black); G, H • G: 5 (red); I • H: 8 (red) y; • I: 4 (red) x;

22. 22. Mathematical expressions • Canot be read in standard notation • Different linear formats • Special applications for reading and doing maths • MATHML

23. 23. linear formats • Hard to read for sighted people • Hard to work with complex expressions • Specially developed formats are better for making "calculations" • Specially developed formats are known only by small group of users • formats: latex, AMS (ascii mathematics shrift-special format), hrTeX (human readable TeX)...

24. 24. lim example

25. 25. Transcription (ams) • Let us define a sequence of functions {f(n;)} (n=1;´%), where a@Inter [n=1;´%] D(f(n;)) (:={x@R; Al n@N : x@D(f(n;))})

26. 26. Syntactic dominance of POS rule

27. 27. Transcription • Al vi, w (i+1;): vi -> (P,POS;) w(i+1;) • Ex v(i+1;): vi -> (P,r;*) v(i+1;) ´& • w(i+1;) -> (P;*) v(i+1;)

28. 28. Special applications • Developed for blind mathematicians • Functionality for doing maths (working with structure, optimized methods for typing mathematical symbols...) • Functionality improving communication with sighted users (MathML support, linear-> 2d transformation...)

29. 29. LAMBDA • One special application • Can import MathML • Provides functionality for doing math • Primarily developed as a tool for secondary school students • Commercial application

30. Resources • Creating accessible documents (in slovak): http://cezap.sk/informacie/tvorba-pristupnych-elektronickych-dokumentov/