Bringing up the topic of metadata usually triggers thoughts about the need to include title and author information in an ebook. While certainly a necessity, this kind of traditional metadata is not what we’re going to delve into now.
One of the big issues facing people with disabilities as they try to enter the ebook market is how to discover the quality of the ebooks they want to buy. One ebook is not the same as another, as we’ve been discussing, and readers need to know what they’re getting when they pay for your product. And you should be rewarded for your commitment to accessibility by having your ebooks stand out from the crowd.
Unfortunately, in the past, once you pushed your ebook into a distribution channel, whatever good work you had done to make your content accessible would become indistinguishable from all the inaccessible content out there to the person on the purchasing end. At about the same time that EPUB 3 was being finalized, however, the people at EDItEUR introduced a new set of accessibility metadata for use in ONIX records. This metadata plugs the information gap.
An ONIX record, if you’re not familiar, is an industry-standard message (xml record) that accompanies your publication, providing distributors with both content and distribution metadata. This information is typically used to market and sell your ebook, and these new properties now allow you to enhance that information with the accessible features your ebook includes. Retailers can then make this information available in the product description, for example, so readers can determine whether the ebook will adequately meet their needs. It’s also not a stretch to imagine this information being integrated into bookstore search engines to allow readers to narrow their results based on their needs.
To include accessibility metadata in your ONIX record, you use the ProductFormFeature element, which is described in the
standard as a composite container for product information (e.g., it is also used to
provide product safety information). To identify that the element contains
accessibility information, it must include a ProductFormFeatureType child element with the value 09, as in the following example:
<ProductFormFeature>
<ProductFormFeatureType>09</ProductFormFeatureType>
…
</ProductFormFeature>
When this value is encountered, it indicates that the value of the sibling ProductFormFeatureValue element is drawn from ONIX for Books codelist 196, which defines the new accessible
properties and the values to use in identifying them. As of writing, this codelist
includes the following properties: