University of Bonn Fraunhofer IAIS
Towards an Open Authoring Tool for Accessible
Slide Presentations

Mirette Elias, Abi James, Steffen Lohmann, Sören Auer, Mike Wald

The 16th International Conference on Computers Helping People with Special Needs (ICCHP 2018)
July 11-13, 2018University of Linz, Austria
University of Southampton Logo
  • Web app for collaborative authoring of inclusive & accessible slides

  • 17 European partners (platform development, contents, trials, etc.)

  • Collaborative creation (and hosting) of OER materials

  • SlideWiki = Wikipedia for Slides
  • Collaborative editing

  • Multi-device delivery

  • Translation

  • Commenting, discussion

  • Question generation

  • Accessibility


  • Which content types, often used in slides, can impact accessibility?

  • What approaches can be used to identify and remediate accessibility issues?

  • Which approach to checking and improving accessibility issues do authors prefer?

screenshot of slidewiki platform

 Example of content in slides

This is a text box

  • Text bullet 1
  • Text bullet 2
  1. numbered list 1
  2. numbered list 2
Photo of beach with wooden stakes in the sea and cloudy sky
Location Max Min
Linz 24°C 14°C
London 23°C 15°C
Right pointing blue arrow.

Accessibility Requirements of Slides

Slide content element Accessibility added by the system Author actions required to improve accessibility
Slide title HTML heading tags Slide should have a unique title.
Text box HTML used for text styling, lists and hyperlinks. Lists and styles are added using the authoring toolbar.
Image Interface for image alt text & captions  Alt text should be meaningful. 
Embedded content Content contained within an accessible iframe using the keyboard and assistive technologies. 
Each iframe should have a title.
Embedded content must be accessilbe e.g. video/audio media, either include captions and/or an audio description, or a transcript and description. 
Equations Equations are embedded as MathML. Avoid adding equations as images
Tables Appropriate HTML tables. Interface for setting headers, caption, text summary. Define headers and provide a caption or text summary of the table if needed.

How can we can encourage authors to improve accessibility?

  1. Require 
  2. Guidance
  3. Encourage
  4. Rate
  5. Crowd-source
  6. Automatic
  • Identified 6 approaches for encouraging authors to improve accessibility

  • Authors were surveyed to assess preferences



1. Require

"I am happy to be required to fix accessibility issues before saving my slides to make them accessible for all users."

Mock up of message in slide editor that requires user to fix accessibility issues

2. Guidance

"I  would like to see accessibility tips and hints while editing my slides to help me make it more accessible to all users."

Mock up of accessibility tips in SlideWiki slide editor

3. Encourage

"I would like to see a list of accessibility warning when I save a slide and have the option to fix them or ignore them."

Mock up of accessibility warnings in SlideWiki slide editor

4. Rate

"I would be happy for my decks to be rated in terms of accessibility as this would encourage me to fix any accessibility issues."

Mock up of SlideWiki search results with accessibility ratings

6. Automatic

"I would like the accessibility of my slides to be fixed automatically, even if this might not resolve all the issues or be accurate."

"I would be encouraged to fix accessibility issues on other slides in order to increase my reputation or rating."

5. Crowd-source


Survey Results: Accessibility Approaches

Chart of the responses by slide authors to questions of whether they agreed with each proposed approach to improving the accessibility of slides.
  • Most popular approaches were "Encourage" and "Guidance". 

  • "Automatic" was least popular.


Spending Time for Accessibility

Chart of responses by slide authors to the question : How long are you willing to spend on improving the accessibility of a slide?

How long are you willing to spend fixing accessibility issues for 1 slide?



  • Six main elements within slides may require content authors to undertake actions to ensure the slides are accessible.

    • Three elements must be checked to ensure content is appropriate to the context.

  • Author's willingness to spend time fixing accessibility issues could be increased through an efficient checking process.

  • SlideWiki platform will warn authors of potential accessibility issues and provide them with guidance as they create content.


Thank you

Presented by Abi James

University of Southampton 

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