Improve Accessibility with DAISY XML Translator — Tips & Best Practices

Improve Accessibility with DAISY XML Translator — Tips & Best PracticesAccessible content is essential for inclusive reading experiences. The DAISY (Digital Accessible Information System) XML format is widely used to create richly structured, navigable, and accessible publications for people who are blind, have low vision, or have other print disabilities. The DAISY XML Translator bridges DAISY XML and other accessible formats (such as EPUB, braille-ready files, and specialized audio formats), making it a critical tool for publishers, accessibility specialists, and developers. This article covers practical tips and best practices to get the most out of a DAISY XML Translator in real-world workflows.

What is DAISY XML and why it matters

DAISY XML is an XML-based format designed to represent the logical structure, semantic roles, and navigation of books and long-form publications. Unlike flat text formats, DAISY XML supports:

• semantic markup for headings, lists, tables, and other structures;
• synchronized audio and text (smil) for read-aloud experiences;
• rich navigation metadata (page lists, landmarks, and table of contents);
• embedding or referencing of alternative content (alt text, descriptions, and braille mappings).

Because assistive technologies rely on semantic structure and metadata to render content meaningfully, converting source materials into well-formed DAISY XML (or converting DAISY XML into other accessible formats) preserves accessibility features across platforms.

Preparing source content for reliable translation

Clean, semantically marked source content reduces errors and improves output quality when using a DAISY XML Translator.

• Use semantic markup from the start: prefer structural tags (headings, sections, lists, figure, table) rather than visual or presentational attributes.
• Keep content modular: separate front matter, body, back matter, and appendices into distinct files or sections to make mapping predictable.
• Provide alternative text and descriptions: every image, chart, or figure should include concise alt text; complex images should have long descriptions or a linked description file.
• Ensure consistent use of heading levels: avoid skipping levels (e.g., h1 → h3) unless structure genuinely warrants it.
• Normalize character encoding to UTF-8 to avoid mangled characters in output formats.
• Validate your source XML against a schema or DTD to catch structural problems early.

Key translator configuration options to watch

Translators vary in features but typically expose several configuration options that affect accessibility:

• Output formats: choose the target (EPUB/EPUB Accessibility, Braille Ready File, DAISY 2.02/3, audio SMIL) appropriate for your audience.
• Navigation granularity: controls whether the translator creates deep navigation (per paragraph/section) or coarse navigation (per chapter).
• Heading mapping: map source heading tags to target-levels explicitly to avoid mis-leveling in the final TOC.
• Image handling: configure whether images are embedded, linked externally, or exported to a separate assets folder; ensure alt text remains attached.
• SMIL/audio synchronization: if generating synchronized audio, configure sampling, chunking rules, and audio file formats (MP3, M4A).
• Braille mapping: specify grade (e.g., Grade 1 vs Grade 2), translator tables, and whether to include contractions.
• CSS and styling: for EPUB, supply a default accessible stylesheet that preserves semantic meaning and ensures readable contrast and scalable text.
• Metadata mapping: ensure ISBN, language, contributor roles, and accessibility metadata (such as accessibilitySummary, schema.org properties) are preserved.

Common pitfalls and how to avoid them

• Lost alt text: verify that image alt attributes map into the target format’s alt or description fields; include fallbacks in configuration.
• Broken navigation: confirm that TOC and page lists are generated and linked properly; test with screen readers and EPUB checkers.
• Headings mis-levelled: set explicit heading mappings and validate TOC structure visually and with accessibility tools.
• Inconsistent audio/text sync: when producing audio, chunk SMIL fragments at logical boundaries (sentences or paragraphs) and test playback on DAISY players.
• Complex tables rendered poorly: convert complex tabular layouts into simplified, semantic tables or provide a linearized table description for screen reader users.
• Character encoding issues: always validate encoding and replace unsupported characters or ensure fonts in EPUB support needed glyphs.
• Missing braille rules: configure correct braille translation tables and test using braille display emulators or real devices.

Workflow examples

1. Publisher: source (Word/HTML) → convert to structured XML → validate → DAISY XML Translator → EPUB Accessibility + braille files → QA with screen reader + braille tester → publish.

2. Academic press: LaTeX source → convert via specialized tools to DAISY XML (preserving math as MathML) → translator outputs EPUB with MathML and fallback images → test in math-capable readers.

3. Library producing audio: Manuscript → DAISY XML with SMIL synchronization → synthesize audio or align human-narrated audio files → package as DAISY audio publication.

Testing and QA checklist

• Validate final files with an EPUB/DAISY validator.
• Test navigation with screen readers (e.g., NVDA, VoiceOver) and DAISY players.
• Verify alt text and long descriptions are present and meaningful.
• Check visual contrast and scalable text in EPUB viewers.
• Review braille output with translation tools and (if possible) a refreshable braille display.
• Play synchronized audio and confirm accurate text highlighting and timing.
• Run automated accessibility checkers, but supplement with manual checks—especially for complex layouts, math, and images.

Tools and resources

• Validators: EPUBCheck, DAISY Validator.
• Screen readers: NVDA (Windows), VoiceOver (macOS/iOS).
• Braille tools: Liblouis, brltty (for testing), braille displays.
• Conversion utilities: Pandoc (with extensions), specialized DAISY conversion suites.
• Testing players: Thorium Reader, EasyReader (for DAISY/EPUB accessibility testing).

Best practices for maintainability and scaling

• Automate the pipeline: use scripts or CI to convert, validate, and package accessible outputs to reduce human error.
• Keep mappings in config files: store heading, image, and metadata mappings in version-controlled configuration to ensure repeatable results.
• Maintain a style and accessibility guide: document required alt text standards, heading practices, and table treatments for authors and editors.
• Train staff: ensure authors, editors, and QA teams understand semantic authoring principles.
• Collect user feedback: involve readers with disabilities in testing and incorporate their feedback into future releases.

Final checklist (quick)

• Use semantic markup and validate source XML.
• Provide alt text and long descriptions for non-text content.
• Configure heading and navigation mapping explicitly.
• Test audio synchronization, braille translation, and navigation.
• Automate conversions and include validators in your workflow.

Improve accessibility with careful source preparation, translator configuration, and thorough testing. When DAISY XML is used as the central interchange format, it preserves structure and semantics across outputs—making publications truly accessible to more readers.