ALT text for a cover page in EPUB3

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Hi,

I am interested in getting a "more educated" opinion about making the cover image of an EPUB3 "accessible".

My first doubt is: should I consider the cover image as "decorative" (and hence with empty alt text) or should I provide an alt text?

After reading

http://www.idpf.org/accessibility/guidelines/content/xhtml/images.php

(especially Example 1) and

http://www.cs.tut.fi/~jkorpela/html/alt.html#thumb

I think that the best option consists in providing in the alt attribute the text displayed by the cover image (e.g., title, author, publisher, possibly narrator and/or translator). Any suggestions about this point?

Second question: I am used to scale the cover image using an SVG container. However, if I use the <title> element for the corresponding alt text, VoiceOver does not render it. For accessibility purposes, given the current screen readers, should I revert to the more basic <img alt=""...>, giving up the "scaling" benefits of the SVG container?

I don't think I can give you a blanket "do this" approach to all cover images, but in general they aren't worth describing extensively, if at all. I can't think of a case in all the books I've converted where they represented anything more than a marketing tool, which is why the alt text for them is often just a simple "cover image" to at least give the reader acknowledgement of what is on the page.

The reason for not detailing the cover is that the cover typically doesn't carry anything more than redundant information for the reader. They'll already know the title and author/editor from the book metadata presented by the reading system. And the title and author are also typically repeated variously on the title page/half title page/title page verso and so on. There are only so many times that a reader wants to be presented this information before it gets tedious to listen to.

If your book contained no front matter, then I would strongly consider including the title and author as the alt, but unless any imagery is important to understanding the story I wouldn't bother describing it. (The alt attribute isn't the proper mechanism for extensive descriptions, too, so a description might better be included in a another element and pointed to via an aria-describedby attribute.)

Hope that gives you some ideas, at least. In my experience, retaining back cover information, such as author bios, is more important than the front cover.

To your second question, are you just using an SVG wrapper on a bitmap image or do you have an SVG? I wouldn't necessarily work around voiceover and lose the scalability of your images to include an alt text of potentially minimal value if it is pure SVG. The scalability can be very helpful for low vision readers, so you're compromising the accessibility of one group for another. I would argue given this limitation that keeping the scalability is more important that ensuring an alt gets read, since covers are a visual medium that doesn't translate well.

If you're just wrapping a bitmap, and you're looking only at epub 3 production, could you use a fixed layout document to achieve the same? Reading systems will typically scale fxl documents to the viewport (at least downward), achieving the same effect of an svg wrapper. I know readium and ibooks do, at least, and the image will fit the viewport provided the aspect ratio matches. You can also give max-width and max-height a try for a low-tech approach.

Hi Matt, thank you for replying

1) After presenting the options to the publisher, they decided to go with a minimal alt text like this: "$TITLE by $AUTHOR, $PUBLISHER, $YEAR" --- which I think it is a reasonable choice, even if a little by redundant given the presence of an half-title page inside the eBook.

2) I am used to use an SVG wrapper to proportionally stretch a bitmap cover image. FXL is not acceptable in this case, so the choice is between retaining the SVG wrapper for the bitmap cover, or replacing it with an <img> with max-width/max-height set. I prefer the first one, too --- I will check back with the publisher.

Again, thanks for your suggestions and help.

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