Recognizing and Overcoming Limitations with Automated Conversions to eBook Formats

Devorah Ashlem, Senior Project Manager, Data Conversion Laboratory, appearing in

You’ve probably encountered a less-than-desirable content experience on a mobile device, like not being able to “pinch” the screen to zoom in and out, or rotating a device and not getting the content to follow suit. You were left with a less than positive impression of that content (and its author), because you couldn’t consume it your way. Time to think about what you can do to avoid giving your readers a less than optimal impression of your work.

To meet the opportunities afforded by an increasingly global, mobile (and demanding) readership, you need to transform your print-based and static web versions of books into digital assets that readers can access anywhere, on any device. You can choose from several options for the actual conversion format including EPUB, the standard open-source (not proprietary to any company) format for eBooks, or MOBI, Amazon’s proprietary format for Kindle. No matter the standard you choose, you are bound to experience some common challenges introduced by mobile characteristics. We’ve outlined some of the biggest challenges you run into when converting for mobile, so you can explore alternatives and best practices to handle them before you start the conversion effort.

Limited Real Estate

Automatic content conversion produces mobile, transportable content, but it introduces different consumption challenges than those that arise with printed books or publications with one specific format that is designed to always be viewed in the contained environment. Mobile devices come with smaller screens than laptops or traditional desktop computers—usually MUCH smaller. Viewing HTML content on a computer often allows you to scroll or zoom to reveal all content within a document. But the limited screen size of mobile devices alters the usability and expectations of the content—they display a small chunk of content at a time. You’ll want to plan the book layout to be the simplest format that meets your functional requirements, so that it maintains context as readers interact with it on a variety of devices.

Integrity in Tables

Standard novels with minimal “extras” present less challenges during the conversion phase than books that include more complexity, such as content stored in multi-column/multi-row tables. If you want readers to be able to search the content within the table, you need to set up the table with appropriate tagging to allow the software to pick up the elements during the conversion process. With tagging comes the potential for the table content to be compressed, distorted, or take up the wrong portion of the screen real estate (resulting in content that’s missing for the reader and likely confusing to the meaning).

If the visual representation of table format is important, but searchability is not, you have the option turn the table into an image. The reader won’t be able to resize it, but you won’t lose any of the content or context of the original table.

Constraints for Images

Inserting images into documents seems simple enough, but in eBook readers that display using “electronic ink” technology, they won’t look the same. A vibrantly colored image in the original document appears in grayscale. And, unfortunately, the ability to increase font size does not carry over into an ability to increase image size. Another issue that may come up is that depending on the size of the image and the size of the screen, the caption may not always flow on the same page as the image. An alternative way to keep them together is to capture the caption as part of the image but the downside is that the caption text will then not be searchable.

Complex Math Formulas

Simple text is easier to convert than complex math or scientific formulas. If your content contains MathML, you can tag it for EPUB 3.0 formatting, but many of the current readers don’t yet support it (Readium and iPad do). MathML is readable on computers with plug-ins for web browsers, but otherwise it likely will render incorrectly, either producing nonsensical text or missing elements when converted to mobile.

You can tag formulas as Unicode characters, which provide a unique number for every character, or as an image if the formulas are too complex to render with just Unicode. But even the image can create an issue once converted; when a reader adjusts the font size, the image will not update to match.

Improve the Content Quality Upfront

The process for automating content conversion to get your book out to mobile devices might seem impossibly complicated. But you can minimize time, money, and headaches by identifying the challenges your content presents for mobile, and by preparing content for the conversion while you write and design the book.

Be prepared to provide some context around the text and other content in your book to the team who will convert it. For example, you might discuss column and row headers, as well as the type of content that is covered within a table.

While you’re at it, ensure that your source file(s) is in the best condition while you’re creating it. This effort upfront reduces the complexity of the automated conversion, which inevitably saves you time and money (in other words, frees you up to focus on more important things, such as writing more books).

If your content is already in HTML for web publication, rather than PDF, your conversion will be easier, as eBooks are written using a form of HTML. PDFs are designed to look on the screen as they should when printed to the page, which is a problem for mobile publishing. eBooks do not contain specific “pages.” They are designed to allow readers to resize text and rotate devices. With HTML, you can plan your content as topics or chunks rather than tying information to specific pages.

With an increasingly global marketplace, you should consider language compatibility. Some eBook formats restrict the type of characters or number of languages. The EPUB3 standard does allow you to tag Hebrew fonts correctly and allow for right-to-left reading, but the output still might not be perfect on all devices.

Mobile publishing success is within your reach; careful planning and an understanding of the challenges within mobile publishing, and the expectations of readers, helps you (and conversion partner) present content in a way that meets everyone’s needs.


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