>Even ebooks that are formatted correctly for TTS can have other issues. Math and science are the worst. Textbooks may be formatted for 100 percent accurate text-to-speech, only to falter when it comes to formulas, equations, charts, and tables. Those are typically rendered as images in an ebook, which would require publishers to take an additional step to record "alt text" for each individual figure—audio that would describe the image once encountered by a screen reader.
My now wife and I spent hundreds of hours during undergrad converting text and graphs to plaintext for a grad student. Truly nasty formulas, with multiple integrals, fractions with many factors above and below the line, exponents all over.
While the legality was questionable at the time, I broke the DRM on the PDF of the book, copied everything to Sublime, removed line breaks, formatted footnotes with [1] formatting, labeled graphs.
Then I fired up GIMP and translated the images. When embossed on paper, braille is much larger than normal text, so I had to greatly simplify things.
The frustrating part was, on math books, there's a good chance it was LaTeX to begin with. The format we converted formulas to was almost identical to LaTeX.
Additionally, surely for undergrad level classes, multiple colleges were each paying undergrad students $1,000+ per course to make the materials accessible. A website where School 1 could see that School 2 had already converted Calculus 1 to braille and allowing payment to reimburse a proportional amount of the cost would be incredible helpful and maybe legal. In essence, $1,000 would be paid by School 1 to do the initial work, School 2 reimburses $500, then School 3 pays $333, split to the other two schools so ultimately, they're all in it for $333 rather than $1,000.
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I also worked with another student to build a molecule generator for 3d printers. Extensive use of the Blender Python API. Each bond type was a different shape connector, and the periodic table was divided by row and column to form a unique combination of scale and shape.
MacMolPlt [1] generated plaintext files that contained the position of each atom, bond connection types, and a list of coordinates for the electron clouds which could also be generated on top of the molecular structure, all exported to .STL for 3d printing.
It was a neat project, definitely opened my eyes to disabilities, and I became a more empathetic person because of it. Through some weird stuff with funding, it's sort of in copyright gray area. The disability office was paying to make things accessible for the student, not necessarily to build a tool that would be released to the greater world. It wouldn't be hard to replicate though. Back in 2011, I knew every 3d printer on campus and was kinda begging to print stuff while we tried things out. Now printing is trivially cheap and capacity is abundant - it would be 10x as easy and helpful.
[1] https://www.swmath.org/software/7039