Suz Hinton on Accessible images (AIMS)

In my latest experimentations in 'Guerilla Accessibility,' I stumbled upon this paper a mere two weeks after publication and was excited about the explorations in it. The ideas built upon an unlikely hero of the anti-surveillance field delighted me. There are wide implementation gaps that remain unaddressed in this paper, and I took liberty on these when implementing the algorithms. I'll be sharing both the triumphs and pitfalls of this proposed technique of improving the accessibility of online web content.

Transcript

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2. a model to build self‐describing
   images for assisting screen
   reader users
   

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3. Topics covered
   Web Accessibility
   Steganography techniques
   Browser Extensions
   

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4. Web Accessibility
   

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5. (A11y)
   

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6. Screen Readers
   

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7. Screen Readers
   JAWS
   NVDA
   VoiceOver
   Speakup
   TalkBack
   

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8. Demo
   

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9. 
   

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10. 
    

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11. Excerpt from Accessible images (AIMS): a model to build self‐describing images for assisting screen reader users
    

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12. Pros
    + Ease of implementation
    + Works with any image MIME type
    + Supported in browsers since
    HTML 2
    

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14. Cons
    – Requires coding knowledge
    – Decoupled from the actual image
    – Plenty* of devs have little to no a11y skills
    *presenter’s observation of peers from over 12 years of experience in front-end development field
    

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17. May 16, 2006 newscientist.com/article/dn9177-gamers-help-the-blind-get-the-picture
    

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19. Steganography
    

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20. Steganography
    the practice of concealing messages
    or information within other
    nonsecret text or data.
    

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25. there are many steganography
    techniques and approaches
    

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26. + concealing text in images
    + using LSB method
    

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27. 1 convert text to bits
    2 store bits in LSBs of pixel data
    

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28. close up photo of a lion facing to the left
    99
    1100011
    ASCII character code
    

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29. 20, 255, 102
    0010100
    LSB
    c
    99
    1100011
    ASCII character code
    save!
    1
    

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33. Assumptions
    ? knowing length of alt text
    ? method to compute bit position in image
    

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34. Knowing the length of alt text
    ? store length in consistent pixel location
    ? use special character to indicate end (EOF?)
    ? NLP (lol no)
    

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35. Computing bit position in image
    ? use a PRNG with seed
    ? decoder needs to know the seed
    

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36. Browser extension
    

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37. Browser extension
    third party script that can run on
    pages loaded by a user
    

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38. Browser extension
    a terrifying way to give third party
    code a same-origin policy waiver
    

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41. Implementation
    noopkat.github.io/a11y-alt-stego
    

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42. Pros
    + Description is portable with image
    + Less code
    + Less effort
    + Rad use of steganography
    

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43. Cons
    – Single language restriction
    – Lossless image format required
    – Compression can destroy / corrupt data
    – Most significant human labor not removed
    – Opt-in, standard adoption challenges
    

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44. thanks
    

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