search

daisy / ace

Ace by DAISY, an Accessibility Checker for EPUB
MIT License
75 stars 22 forks source link

Add @longdescription into Images HTML report #351

Closed LaZay closed 3 years ago

LaZay commented 3 years ago

For some images, we plan to manage long descriptions with the @longdescription attribute, together with the short descriptions @alt attribute. We would like to check the integration of both descriptions (long+short) in our EPUBs via Ace. Nota 1: the @aria-describedby attribute does not say wether it addresses a short or a long description. Moreover, it should rather be used when a piece of visible text is already covering the need of image description. Nota 2: long descriptions are absolutely necessary for images representing handwritten letters, sophisticated tables or graphs, otherwise information would be totally missing for the blinds! It is much more "than nice to have".

So far, the HTML Images report does not include a longdesc. Could you add a new colomn in the HTML table with it? To display long descriptions values? Showing either the @longdesc URI (without resolving it), or the HTML structured content addressed by the URI. The second solution would be much nicer of course, but probably more difficult to implement, as long descriptions are generally structured into HTML block elements.

Thanks!

LaZay commented 3 years ago

Forget about this ticket. I just discovered that @longdesc attribute is not even supported by HTML5 / EPUB3! And that @aria-describedby attribute is the only proper way to point out a long descriptions today. https://github.com/w3c/epubcheck/issues/668 https://www.w3.org/WAI/GL/wiki/Using_aria-describedby_to_provide_descriptions_of_images @aria-describedby is already reported in Images HTML table. So everything is OK in the table format.