The DAISY Consortium wishes to support talking book programs in libraries and agencies which operate under legally-mandated requirements to protect intellectual property. While the specific provisions of these laws vary from country to country, they generally allow libraries and agencies to publish copyrighted matter for their clients with print disabilities under special exemptions from customary commercial considerations, utilizing "specialized formats" not generally available to the public.
The first encryption specification designed to turn a book into a Protected Digital Talking Book (PDTB Version 1) was not made available to the public. The subsequent specification (PDTB Version 2) defines a means for further specializing these formats by describing various transformations which may be applied to DAISY and ANSI/NISO digital talking books. These transformations, based on standard information technology techniques, will prevent content from being displayed in reading systems or other user presentation technologies unless appropriately authorized by the issuing library, agency, or publisher. The specification is designed in such a way that a single reading system can be authorized to process books from multiple libraries, agencies, or publishers.
The specification describes the technical means by which digital talking books can be issued in a protected format. It is intended as a specification for transforming existing unprotected digital talking books into a protected format using simple encryption means.
Relevant Position Paper:
The official PDTB working group activity has completed. The Protected Digital Talking Book Specification Version 2 is in maintenance mode.