EditorErin Mallory is the manager of cross-media at House of Anansi Press, which has been publishing ebooks (in addition to its print books) since 2009. Mallory launched the Indexing Society of Canada’s 2014 conference with an overview of the current state of ebook indexing workflows.
Ebook formats
Ebooks come in three main formats:
- PDFs support some multimedia and interactivity and are easy to create but have limited sales channels. The static format of PDFs makes them popular for technical or reference books but may create poor reading experience for readers using certain devices (for example, trying to read on a smartphone).
- EPUB is the most popular ebook format and is essentially a self-contained website, using XML and CSS. Text is reflowable. EPUB is a neutral, standard format compatible with all current e-readers except the Kindle. EPUB 2, still the most commonly used version, is based on HTML 4 and CSS 2. EPUB 3 is a newer format, with many improvements in functionality, accommodating languages that read vertically or from right to left, as well as MathML.
- MOBI is also based on XML and CSS but is proprietary to Amazon and is compatible only with Kindle devices and apps.
The main reading engines are:
- Adobe Reader Mobile SDK, which renders ebooks on Adobe Digital Editions, Kobo, and Nook.
- WebKit, which renders ebooks on most mobile e-readers, including the iPad, and browser-based e-readers.
Publisher’s considerations
Ebook indexes are really only useful if they are fully hyperlinked. Until recently, hand coding each hyperlink was the only way to create a fully functional ebook index, so publishers had to consider the return on investment. Not only is creating an ebook index time consuming, but proofing the index adds time to the quality-assurance process.
Further, the publisher has to consider what devices its audience is using. First-generation Kindles and Kobos don’t support hyperlinking, and not all e-readers support a “back to” function.
Because of these limitations, Anansi decided when it launched its ebook program in 2009 not to include indexes in ebooks at all. Today, the publisher has adopted a workflow that has streamlined some aspects of ebook index creation.
Recent improvements
Scripts for Adobe Creative Suite 5+ can be very useful; some auto-generate cross-references in a formatted index that are maintained when exported to EPUB. The scripts aren’t perfect, so some (about half) of the links still need to be hand coded. These scripts use styles, so if a designer hasn’t properly styled the index, they won’t work properly.
There are also scripts that convert an external index (for example, one created in Word or a program like Cindex) to create an index in InDesign that is maintained on PDF export.
The Creative Cloud version of InDesign allows for linked indexes to be exported into EPUB. Publishers can be reluctant to relinquish control of their InDesign files to an indexer, but Mallory acknowledges that if professional indexers can save the time by embedding the index, publishers may have to push aside their reluctance and find ways of working with them.
Project considerations
For each project, ask yourself the following:
- Does your ebook need an index?
- Does the index have to match the print book?
- What devices will your readers use?
- Can the index be adapted to better serve the digital reading experience?
- Can you change your indexing workflow to simplify the ebook index creation process?
- What kind of markers do you want to use?
Mallory points out that in an ebook, using page numbers may not make the most sense. Some indexers in the audience remarked that seeing a page range communicates important information about subject coverage. InDesign indexes can allow the range to be listed but link only the first page number.
(On Day 2 of the conference, Judy Dunlop gave an excellent summary of the workflow she used in a recent project doing embedded indexing in InDesign Creative Cloud. Post coming soon!)
An additional resource is LiveIndex (http://www.id-extras.com/products/liveindex), an InDesign script for CS5 and up (including the latest CC2015), that converts all page numbers in an index to live hyperlinks and works both for ePub and PDF export.