Converting From InDesign to Kindle
The following is an excerpt from the feature article, "From InDesign to Kindle" by Kevin Callahan, in the April 2015 issue of InDesign Magazine. Learn more from Kevin about publishing to Kindle in his session at PePcon: the Print + ePublishing Conference.
As Callahan explains in this feature story, Adobe InDesign can't export directly to the proprietary Kindle ebook format (KF8/Mobi), but it can export to the open source industry standard EPUB format used by iBooks, Kobo, and other eReader software. The good news is that Amazon offers a free EPUB-to-Kindle converter utility called Kindle Previewer.
So, the basic InDesign to Kindle workflow is to export the INDD file to EPUB (Reflowable), edit the contents of the EPUB file to optimize the markup for KF8, then convert the modified EPUB to KF8 format with Kindle Previewer. Following are some of the edits that Callahan suggests you might want to make to the EPUB file before converting it to Kindle.
There are some differences between the display of features in reflowable EPUB and Kindle environments. You'll need to dig into your exported EPUB to check on a few specific elements before it's ready for KF8 creation.
To do this work, you'll need access to the files inside an EPUB. If you're working in Windows, change the name of the file from book.epub to book.zip and unzip it. If you're on a Mac, you'll need a utility like ePub Zip-Unzip (available from the MobileReads forum, an essential resource on most things ebooks).
Once you've cracked open the EPUB you'll have access to the XHTML and CSS files. I use either TextWrangler or Dreamweaver to edit. If you want to work within the zipped EPUB, oXygen Author and BBEdit open an EPUB without unzipping it. Sigil is a similar (and free) choice, but it doesn't currently support EPUB 3.
Once you have your hands on the XHTML and CSS, here are some issues to address:
»» Anchor tags (such as from linked TOCs): How are they inserted in the HTML? InDesign places them inside the HTML tag, but KF8 prefers them outside:
EPUB from InDesign:
»» Drop caps: Kindle guidelines recommend using percentages to specify the font size of a drop cap; the usual EPUB practice is to use ems as the unit of measurement. I swap in CSS in percentages while I'm on my way from EPUB to KF8.
»» Covers: Delete the cover.xhtml that InDesign generates if you've designated a cover during EPUB export. KF8 doesn't want it, and leaving it in results in two covers being displayed. Modify your content.opf to remove the file from the Manifest and Spine, and remove links to this page from your toc.ncx, navigation file, and internal table of contents.
»» Book elements: The Guide, which appears in the content.opf of the EPUB, points reading systems to book elements. Kindle supports only the Cover, Go to Beginning, and Table of Contents guide elements. Kindle also supports the landmarks nav list (inside the EPUB 3 navigation document, usually named toc.xhtml).
»» Fonts: Neither EPUB nor KF8 allow PostScript fonts, but they do recognize OpenType (OTF) and TrueType (TTF). Some of these fonts contain PostScript information, which will generate a warning on conversion to KF8. The file will still work with the warning.
Will Amazon ever come into the EPUB fold? I don't think so; all indications are that they will continue developing KF8. As long as it remains close to the EPUB 3 standard for reflowable ebooks, conversion will be necessary and allowances will always need to be made.