Accessible Reflowable ebooks with Circular Software

Follow these steps to create WCAG 'AA' accessible reflowable EPUB3 directly from InDesign with Circular Software.

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Adobe InDesign fails to create EPUBs to the standards required for modern accessible publishing.

"Despite being widely used by publishers of all sizes as the industry standard page layout tool for PDF and print production, InDesign is found to be not fit for purpose for those wanting to publish accessible EPUB publications…"
Ken Jones, Circular Software

Whilst Adobe InDesign can export to EPUB, the open standard for accessible digital publications, by using InDesign alone, publishers are left with errors and a lack of accessibility.

Exporting WCAG 'AA' accessible reflowable EPUB3 directly from InDesign and with no coding is possible when using Circular Software. Read more about this topic here No-Code Accessibility for InDesign.

Whilst not all reflowable EPUBS will require all these steps, we do recommend following them, in this order, for the best results. Especially for your first few publications.

The steps to follow are listed below. Let's get started!

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Step 1.

Styles & Heading hierarchy.

  • The use of Paragraph and Character styles makes it easier to manage text in general and is used to apply the correct content tags to ebook text
  • The use of heading tags ensures users do not have to rely on visual styling to understand and navigate the document

For the best accessibility headings should be applied using Heading tags. Also the order of the headings should be logical. A H1 tag is the top level with a secondary level of heading, an H2 following an H1.

Heading tags apply structure to content and can be used for navigation so should be applied in order. e.g. it is not correct practice to follow an H1 tag with an H3 tag. More info on heading hierarchy on the DAISY Accessible Publishing Knowledge Base.

Heading levels are applied by the use of InDesign paragraph styles and InDesign has a useful feature to view and edit all export tags in one dialog (InDesign Paragraph Styles Panel options > Edit All Export Tags…) More info Edit All Export Tags on EPUB Secrets.

Circular Software has tools and checks to ensure heading, paragraph and word level tags are applied in the most useful way.

Label paragraph export tags
Analyse character style tags

All fonts used should be OpenType or TrueType and active in InDesign. For fonts to carry through in to Amazon Ready reflowable ebooks we recommend using Adobe Fonts which are the embedded into the Amazon file that is exported with Circular Software.

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Step 2.

Threads & Sections.

  • A reader being able to know their current location in an EPUB and to be able to effectively navigate an ebook is a large part of accessibility.
  • Text threads in InDesign chain together multiple text frames so they can contain a long passage of text (InDesign calls these stories).
  • Section labels are added into the EPUB page code to identify the kind of content that is on the page and major sections become landmarks to help with the navigation of EPUB. e.g. the cover, table of contents, and the start of the main body matter.

Text frames that have been 'threaded' can appear on the same page or span across multiple pages and spreads. For long text led publications it is not unusual for the entire main text to be one long thread of text frames covering dozens or hundreds of pages.

Show text threads are.shown in InDesign InDesign View Menu > Extras > Show / Hide Text Threads (tip: make sure a text frame is selected to see it's threads)

For ebook accessibility the order that text frames are threaded together is expected to be in sequence. Unusual text threads that jump over pages or thread content backwards in page order have been found to affect the successful creation and the subsequent reading order of reflowable ebooks.

The Accessibility Tools panel in CircularFLO or GreenLight has a Section Labels section. Use the Section label tools to mark the starting pages of each section.

The Auto add section label to pages tool looks at the paragraph style applied to the first item on the page and if a match is found for an avilable label. After using the auto tool, manually check locations of Section labels and remove any duplicates.

Section markers are added as text frames on the pasteboard on the non-printing FLO_INFO layer.

Remove a section marker by deleting the text frame object in InDesign.

Accessibility Tools Panel
Add section label to active page
Auto add section labels to pages

More info on Text Threads from Adobe.

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Step 3.

Reading Order & Anchored IMAGES.

  • As soon as there is more then one object on a page then the order in which that content is to be read becomes important
  • For good accessibility we need assume that the visual cues offered by text size and formatting are not enough and so we add the reading order

When faced with a well designed but complex spread an experienced, sighted reader will quickly make subconscious decisions on the hierarchy and reading order.

Circular Software reading order tools give us a way to add reading order by selecting objects in sequence or drawing regions over the page.

When pages have none or only one object (e.g. text frame) on the pages there is no need to mark the reading order.

The applied reading order is shown with overlaid non-printing visual markers on the page which can be shared with others for approval.

Once added reading order can be modified.

Items on InDesign Parent Pages (aka Master Pages) are not added to the reading order and do not need to be marked for reflowable ebooks.

More info on InDesign Parent Pages from Adobe.

Auto define reading order
Manually define reading order

Along with text frames, images and their captions are added into the reading order. For reflowable ebooks we anchor images into text at the most appropriate position for them to appear in the ebook.

More info on Anchoring images from Adobe.

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Step 4.

Image descriptions.

  • Adding descriptions to images is an important way to add their meaning to those who may not be able to view them
  • Background images, decorative images and images that are fully described by on page captions should be marked as such

Rather than placing alt text descriptions into image metadata, the best descriptions take the context of the image or region on the page along with the intended audience into consideration.

Circular Software tools allow the addition and editing of descriptions to images and regions directly on the InDesign page, which are able to be shared with others, then apply the descriptions in the final output.

Circular Software tools talk with SIDD (Simple Image Descriptions Database) to connect people, documents and images to a lightweight but powerful and centralized source for contextual image descriptions.

Add / update image descriptions
SIDD (Simple Image Descriptions Database)
SIDD (Simple Image Descriptions) Setup
Simple Image Descriptions (SIDD) Tool
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Step 5.

Table of Contents.

  • Reflowable EPUBs typically should benefit from an internal table of contents within the EPUB code which helps with navigation.
  • Printed contents pages are often added as text rather than by using the InDesign table of contents feature, which makes them inaccessible.

Although InDesign has a table of contents feature, it is not always used. Circular Software tools have the ability to add an accessible table of contents to any ebook.

Because a page list is automatically added by Circular Software on export, specifying a page number in CircularFLO Contnets Panel is enough to link to that page's starting point.

Chapter titles can be extrcated ready to use in the Table of Contents Panel by using the Add Section markers to TOC tool.

Add Table of Contents Panel
Add Section markers to TOC
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Step 6.

Check Text contrast.

  • Insufficient contrast between text and background colours can affect everyone but contrast is of greater importance for those with sight difficulties.
  • A Circular Software tool takes the colours from selected InDesign objects and report their contrast ratios.

For print work, a text size above 18pt means a lower contrast ratio can be used but for fixed-layout ebooks, although text maybe larger in print, a smaller screen size may affect the actual size.

More info and help is available at the WebAIM Contrast Checker page.

Text Contrast tool
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Step 7.

Add Accessibility metadata.

  • By declaring just how accessible (or not!) an EPUB file is, we can inform the retailer and reader about the features that the ebook has before purchase or download
  • Adding accessibility metadata is now a requirement for accessible EPUB

Structured information about the EPUB content lets everyone know the accessibility features and potential hazards. The expected structure for this metadata is ' metadata' and this is part of the EPUB3.2 standard and later.

More info on Accessibility Metadata on the DAISY Accessible Publishing Knowledge Base.

InDesign 2024.2 does have a way to add this metadata but all Circular Software users can more easily add A11y metadata to their InDesign files and exports by adding using the CircularFLO Metadata Panel.

Accessibility metadata
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Step 8.

Add preferences panel

  • The CircularFLO Preferences Panel adds custom instructions that control the export of your document

With no CircularFLO Preferences Panel added the default values are used.

For reflowable ebooks especially, check that the language shown reflects the main / majority language used for the text in the book.

Auto conversion to the best Amazon file format (clue: it is still not EPUB despite what you may have been told!) can be triggered when Export Amazon ready file is chosen in the Output Options of the Preferences Panel and Kindle Previewer 3 is installed.

CircularFLO Preferences Panel
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Step 9.

Run GreenLight AccessIBILITy CHEcks.

  • InDesign file set up and preparation is automatically checked and help given where needed
  • Spot and fix any issues whilst in InDesign, before exporting to EPUB

GreenLight from Circular Software ensures InDesign files are correct, complete and consistent. GreenLight comes in Custom, Pro and Free versions and we have made GreenLight FREE free of charge to run accessibility checklists. More info here.

With GreenLight installed, select and run the GreenLight FREE checklist Accessibility Checks - Reflowable EPUB to check the readiness of the InDesign file or book. Checks include:

  • Links & Image descriptions
  • Styles & Headings
  • Metadata
  • Structure & Threads
  • Image anchoring
Selecting Checklists
Run a GreenLight checklist on a document
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Step 10.

Export with CircularFLO.

  • All the file preparation from the previous steps using Circular Software tools and checks is now applied by exporting with CircularFLO
  • Create accesible reflowable EPUB / Amazon file with no coding required

Page lists, an essential accessibility requirement, are auto added by Circular Software on export.

Click the Create Reflowable EPUB / Amazon file button on the Main Panel (Tools menu > Main Panel) to export two fixed-layout files.

For reflowable a single export creates both the Reflowable EPUB3 and an Amazon refloable file (KPF).

This is the best method for Amazon file creation and is a better approach than using the same EPUB export (despite what you may have heard!).

The Amazon fixed layout KF8 file is auto created when chosen in the Preferences Panel and will be triggered when Kindle Previewer 3 is installed.

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Step 11.

Validation & testing.

  • Automatically run epubcheck on your exports to ensure they are valid EPUB3
  • Run additional automated accessibility checks

Post export validation with Pagina EPUB-Checker and accessibility checking with ACE, by DAISY can also be set up.

Select the options in the CircularFLO Preferences Panel to run these two automated checks at the end of the export process.

We recommend downloading these tools before your first conversion.

EPUB validity with Pagina EPUB-Checker
Accessibility reports with Ace, by DAISY