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For publishers : Testing your ePubs with Bookworm

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Bookworm isn't just for readers. Publishers can use it to test their ePub files before distributing them, and to experiment with advanced features such as stylesheets and SVG.

Be sure that your ePubs are correct

Verify that your ePub is valid. Many tools creating ePubs do not create them with all of the required attributes and files. Some ePub readers are very loose in what they accept, so checking your ePub in Adobe Digital Editions is not sufficient to be certain that your ebook will be readable everywhere.

Validating with EpubCheck

While developers can download and install their own copy of Adobe's epubcheck tool, it may be easier to use Threepress's web-based ePub validator. It uses epubcheck but wraps it in a convenient web form upload.

Although Bookworm will accept many kinds of ePubs which are not strictly valid, it is always best to test them first. Valid ePubs are much more likely to work consistently with new ereaders that are developed in the future.

How to test ePubs with Bookworm

Like any other user, all you need to do to test ePubs with Bookworm is to sign up and add a book.

Once your book has been added, click around and make sure it looks right. Here are some additional testing tips:

Testing checklist

  1. Is the metadata correct? You can view a book's metadata on the Book information page available from the table of contents of any book.
  2. Is the copyright information in the metadata present and accurate? Readers need to know if the book has full copyright protection, is public domain, or is released with limited rights reserved via Creative Commons.
  3. Is the table of contents correct and in the right order? Bookworm uses the playOrder attribute of the NCX file and the ordering of the items in the TOC.
  4. Are all images appearing? Bookworm can accommodate a wide variety of link forms, from images linked directly from the TOC to those found in anchor tags within content. The images must be listed in the OPF file to appear in Bookworm, as directed by the ePub specification.
  5. Are all special or foreign characters displaying correctly? ePub books complying with the specification must be encoded with either UTF-8 or UTF-16, but Bookworm supports only UTF-8. (Bidirectional text is supported but you will need to include that directive in the CSS.)

Are ePub files on Bookworm secure?

Although Bookworm is designed to prevent file sharing and accidental release of books into the "wild," we accept no liability for software failure which may result in an ebook becoming publicly viewable.

However, Threepress can arrange for a private version of Bookworm to be set up for large-scale testing or especially-sensitive material. Contact bookworm@oreilly.com for more details.