What is a DTB?
The DAISY DTB is a collection of digital files. These may contain digital audio recordings of human or synthetic speech, marked up text, and a range of machine-readable files.
The structure of the book is created using XML tags and is accessible via a browser or a playback device. The DAISY DTB utilizes commonly used web technologies with some additional specialized applications.
Who use Digital Talking Books?
The audience for DTBs varies:
- users who may benefit from the multi-function aspects of a DTB
- blind and low-vision users who want to access DTB versions of print books
- dyslexic users, for whom a DTB may be easier and more enjoyable to read than a print-based text
- English as Second Language (ESL) students, who may benefit from the variety of types of access (audio, text)
- educators, who may create and use regular or custom-made DTBs tailored to their individual student needs
Three basic types of DAISY DTBs:
- Audio with NCX: DTB with structure. The NCX is the Navigation Control Center, a file containing all points in the book to which the user may navigate. The XML textual content file, if present, contains the structure of the book. It may also contain links to features such as narrated footnotes, etc. Some DTBs may also contain additional textual components, for example, index or glossary, supporting keyword searching.
- Audio and full text: DTB with structure and complete text and audio. This form of a DTB is the most complete and provides the richest reading experience. The XML textual content file contains the structure and the full text of the book. Audio and text are synchronized.
- Text and no audio: DTB without audio. The XML textual content file contains the structure and full text of the book. There are no audio files. This type of DAISY DTB may, for example, be rendered with synthetic speech or with a refreshable braille display.
XML provides the producer with the ability to structure a book in great detail. Compared to HTML markup, XML increases markup options making a more detailed structure and proper nesting possible.
DTBs produced according to the DAISY Structure Guidelines are not dependent on distribution medium. The digital master file can be archived and may also be distributed using media such as SD cards, USB flash drives, CDs or DVDs. Patrons can also access these books using apps - utilizing the DAISY Online Delivery Protocol.