About the STSThe focus of this Special Thematic Session (STS) is on approaches and strategies for making «complex document substructures» – like graphs, formulae, diagrams, maps, technical drawings, sheet music, and so forth – really accessible, as opposed to substituting them by alternate description attributes or by adding some raw data as an alternate representation.The STS will be part of ICCHP (International Conference on Computers Helping People with Special Needs) 2016 in Linz (Austria). The STS is chaired by Olaf Drümmer, CEO of callas software.IntroductionDaily communication as much as scientific literature or educational content is full of graphical content. Due to the fact that no widely used technology can adequately represent graphical content in a fashion that it can be accessed reasonably well by everyone, including people with disabilities, ‘pseudo accessibility’ has become the norm by attaching an alternate description to instances of graphical content.As the majority of today’s digital graphical content originates from rich source data, there is no reason why an improved encoding of graphical content could not provide a very valuable foundation for rich and flexible access to it, even without additional effort from content creators.  Obviously it is not only necessary to implement tools that can encode graphical content in a much richer and more interoperable fashion, but also to offer reading tools and assistive technology that can take advantage thereof.One of the more frustrating areas has been the fact that SVG despite all the hope many people had for it, so far has not succeeded in becoming the platform on which to build encoding of accessible graphical content.Nonetheless, there are also areas where some progress has been made, most notably in the form of MathML which is now (as much as SVG) an integral part of HTML5. A variety of tools exist to create MathML, and some tools are available that make MathML encoded formulas accessible in a number of ways.Call for Papers - Suggested TopicsIt is the session chair’s belief that one of the main reasons for the current state of affairs is the lack of agreed upon concepts that could provide guidance for further developments and related research in this field. On this background this STS invites contributions in the following areas – whether presentation of concepts, demonstration of prototypes, empirical research or other types of contributions:

• classification of complex document substructures
• semiology for selected classes of complex document substructures
• typical structural templates for certain types of complex document substructures
• core aspects of encoding and accessing complex document substructures
• ways of accessing or interacting with complex document substructures
• functional roles of complex document substructures, and how to avoid loss of sich functionality
• accessibility aspects in the context of and opposed to usability aspects

An incomplete list of complex document substructures that are considered to be of interest:

• bar charts, histograms, pie charts, line charts, scatter plots, box plots, function graphs,  Venn diagrams, spider charts
• world maps, street maps, city maps, transit maps, weather maps, nautical charts, heat maps, contour maps, spectrograms
• Gantt charts
• tree structures, mind maps, organization charts
• network diagrams, drawings of electrical or electronic circuits, flow charts, UML component diagrams
• mathematical formulae
• geometry
• chemical formulas, Lewis structures
• music notation
• floor plans, CAD models (2D, 3D)
• …

Contact and ContributionAny questions about the STS can be directed to Olaf Drümmer (o.druemmer@callassoftware.com).

Chair

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  Olaf Drümmer, CEO of callas software and Member of the PDF Universal Accessibility Committee within ISO TC 171