Well Tagged PDF Video Examples
Mathematics is traditionally hard to automatically present.
In the untagged PDF the screen reader is just passed the raw character data. The superscript in the first equation is not read, so losing the meaning, and the matrix equation is completely scrambled with the entries being read in the wrong order.
At the present time different PDF readers support different ways of tagging mathematics, here we present a version with math tagged with Associated files containing MathML, which is understood by foxit, and a version with the same MathML used as PDF Structure Element tagging, which is understood by Acrobat. Identical readings are generated as in either case the resulting MathML is passed via NVDA to MathCat to generate the reading.
We expect that this is a temporary situation and that PDF readers will soon support both mechanisms to supply MathML to the accessibility tools. However for now, we need to build two separate PDFs, one using Associated Files, and one with Structure Elements, to support current PDF viewers.
Associated Files and foxit
Structure Elements and Acrobat
Autotagged with Acrobat