PDF Accessibility

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In recent years speech recognition and text-to-speech (TTS) conversion has become part of everyday life for many people, whether visually impaired or not. The most familiar technology is provided as interactive audio services, including Amazon's Alexa, Google's Assistant, and Apple's Siri. Many devices, from mobile phones to desktop computers now support speech recognition and synthesis, with a wide range of selectable voices, languages and related settings. In addition, speech-to-text (STT) technologies are having a renewed level of interest and success, despite many earlier attempts to develop this area of technology. Amazon's Transcribe program is a good example of this, as is Google Speech-to-Text cloud service.

To date there have been relatively few concerns about the security of speech enabled devices and associated software, although there are some obvious issues of privacy and biometrics that will arise as such systems become more widely used.

For users with partial visual impairment, severe dyslexia, and a range of other constraints on reading, facilities exist in the Javelin3 PDF readers to provide text to speech. The recommended approach is to select a block of text in the document and select the text-to-speech key sequence or pop-up option for that section of text to be read aloud. Selected text is best otherwise the facility will try and read the entire page or book from start to finish, and generally this does not work well with most PDFs because of their complex structure. All Javelin3 readers support this functionality (MacOS, Windows, Android), although Javelin for iOS does not (at present).

For users with more severe conditions, such as total blindness or physical disabilities that make reading print or screen-based materials impossible, there are a number of additional options available. In general the source material, in whatever format, will need to be converted to one or more alternative formats. Examples include production of an audio version of a publication, and the conversion of source text to Braille or formats for specialist reader devices. Ensuring PDFs and web materials have excellent navigation facilities and a reasonably linear content structure helps a great deal. A useful video on these issues as they affect web page design in particular, see: here.

Conversion of files for a range of disabilities is provided by a number of organizations, for example the specialist e-text unit at Georgia Tech