analyze accessibility metadata

[marisademeglio]

Right now, Ace summarizes what's present/missing regarding the accessibility metadata in the package document. There are two ways to improve upon this:

• include what's in the content documents (perhaps as a part of content analysis -- see this example of embedded video metadata: https://idpf.github.io/a11y-guidelines/content/meta/schema.org.html#meta010-ex02)
• suggest values for missing metadata

[murata2makoto]

Yoshimura-san and Ando-san considered which value of
accessibilityFeature should be added by programs. Here is a rough
proposal.

1) Always assign these values

readingOrder
tableOfContents

2) Programs can determine these values

MathML
ttsMarkup

3) Programs can suggest these values

annotations
alternativeText
audioDescription
bookmarks
captions
describedMath
longDescription
displayTransformability
printPageNumbers
rubyAnnotations
structuralNavigation
synchronizedAudioText
timingControl
unlocked
transcript

4) Not sure

braille
ChemML
latex
highContrastAudio
highContrastDisplay
largePrint
taggedPDF
signLanguage
tactileGraphic
tactileObject

[mattgarrish]

You cannot always assume that table of contents and reading order apply. It still takes manual evaluation to check the quality. Incorrectly listed documents in the spine is not a feature, for example, nor would be a table of contents with one link to the body matter. There are other ways these could be done so poorly as to be useless for accessibility.

I would only suggest them, but, yes, they could always be suggested.

[rdeltour]

Thank you Murata-san, Yoshimura-san, and Ando-san! The list sound about right to me, with the added caveat from Matt.