http://www.loc.gov/nls/dtbfaq.html
NLS: That All May Read Frequently Asked Questions: Digital Talking Books
1. I've heard that the National Library Service for the Blind and Physically
Handicapped (NLS) is planning to change talking books to a "digital" format.
What does this mean?
For nearly thirty years, the primary format for talking books has been
cassette. Before that, they were recorded on phonograph records. Both of
these formats are "analog," meaning that the records and tapes physically
store a replica of the sound of the narrator's voice. Specifically, when the
narrator's voice got a bit louder, the groove of the record actually moved
farther from side to side, and, on a cassette, more magnetic particles lined
up in the same direction. In a digital format, measurements of the
narrator's unique sound waves are stored as digits-ones and zeros-the way
computers operate. The Internet, CDs, DVDs, and memory cards for digital
cameras all process and store information in digital form. Advantages to
storing audio recordings as numbers include the ability to improve audio
quality, the ability to use the same recording in a greater variety of ways,
and the ability to integrate recorded information into a wide
range of systems.
2. Will there be any advantages for the user with this new format?
Yes, there will be many advantages for users. Besides the potential for
improved sound quality, a digital format will offer convenience to users,
who will no longer need to turn over cassettes or change side-selector
switches. Users will be able to jump forward or back by chapter, set
bookmarks, and vary playback speed without affecting the pitch of the
reader's voice. In some books, users will be able to jump by paragraph, turn
on or off selected parts of the book (e.g., footnotes), do keyword searches,
or hear selected words spelled.
3. Will there be a new playback machine?
Yes. Because digital talking books will be recorded on a new medium, and
playback will involve many new features, NLS may develop two new playback
machines. Both machines are expected to be smaller and lighter than the
current C-1. One will have only a few controls and be easy to operate; the
other will have more controls, offering the user more features.
4. On what kind of medium will the digital books be recorded?
Many factors will determine the physical medium for the digital talking book.
Copyright law requires that the materials circulated be in a "specialized
format" not usable by the general public. The medium must be resistant to
damage both in the mail and in the hands of users. The medium must be low in
cost, and able to accommodate a print/braille label. NLS staff envisions
that some type of flash memory cartridge would best meet these needs.
Although somewhat larger, it will be like those used in digital cameras. The
final decision about medium will depend on the durability, cost, and
availability of appropriate technology at the time it is needed.
5. Has NLS considered putting digital talking books on compact disc?
Yes. However, extensive research revealed many reasons why compact discs (CDs)
would not be the ideal choice for NLS talking books. Contrary to popular
belief, CDs are not durable. They can be easily damaged. People with limited
dexterity find them difficult to handle. In addition, because the playback
mechanism for compact discs is fragile, CD players would be prone to damage
in transit and would require frequent repair or replacement.
6. I've heard that a new NISO standard for digital talking books has just
been approved. Please explain.
In December 2001, members of the National Information Standards Organization
(NISO) voted to approve "Specifications for the Digital Talking Book" as an
American National Standard. On March 6, 2002, the digital talking-book
standard was approved by the American National Standards Institute (ANSI) as
ANSI/NISO Z39.86-2002. The digital talking-book standard is the result of
nearly five years of effort by an international committee comprising
representatives from the community of users, librarians, advocacy groups,
manufacturers, producers, international borrowers, and lenders. NLS led the
effort begun in 1997 all the way to final adoption of the standard. The
digital talking-book standard defines the structure and content of the set
of electronic files that together constitute a digital talking book. These
files are arranged to present print information to the reader via
alternative formats. The most common format, of course, will be
human speech. However, a digital talking book produced in accordance with
the ANSI/NISO standard could include a file that contains the contents of
the document in text form. This would enable output via synthetic speech,
refreshable braille, or enlarged visual display of the text. Because of the
expense involved, NLS is not likely to produce many digital talking books
incorporating text files. However, the capability will be there when needed.
7. I've heard of DAISY; will materials produced by NLS be compatible with
this format?
The DAISY (Digital Audio-based Information System) Consortium is working on
many of the same digital talking-book issues. NLS is closely monitoring their
work and collaborating on key initiatives. DAISY has developed and implemented
several digital talking-book specifications, adding new features to each
version. The consortium will include the ANSI/NISO digital talking-book
standard as the most advanced in their set of specifications. Thus,
materials produced by NLS will be compatible with DAISY players compliant
with the ANSI/NISO digital talking-book standard, but not with players
produced for earlier DAISY specifications.
8. Will any of the older NLS-produced titles be available in this new
format?
Yes, the NLS Collection Development Section (CDS) staff has begun a multiyear
analysis of the cassette book collection, identifying the titles most
appropriate for conversion. In 2001, CDS chose an initial 1,000 titles to be
put in digital format. Identification of these titles created a cross
section of the recorded book collection, with genres selected in proportion
to their representation in the full catalog. For this first group, CDS chose
titles it judged to be of most enduring value. The process will be repeated
in 2002 and subsequent years, with the annual number of selected titles
increasing as needed to meet production goals. This approach assures that
when NLS begins to distribute books in a digital format, a broad,
representative range of titles will be available to readers. It is
planned that, by 2008, retrospective audio titles cumulated since 2001 along
with full annual production of current titles begun in 2004 will
comprise a collection of 16,000 titles in digital format.
9. When will I see this new format?
The transition to a digital format will be a deliberate process consisting
of several phases. Initially, small tests will be conducted involving a limited
number of users. As results are known and the ultimate direction becomes
clearer, larger field tests will be conducted. By the end of 2008, NLS
plans to have 50,000 digital talking-book players available, with larger
numbers produced in subsequent years until all NLS users have access to the
new format.
10. Will there be any change for magazines?
Since magazines tend to be smaller and more ephemeral in nature, a wider range
of distribution scenarios may be practical and cost-effective. The flash
memory cartridges being considered for distributing books may be too
expensive to use with magazines, which are not returned to libraries. It is
possible that magazines may stay on cassette for an additional few years.
When conversion becomes necessary because of equipment and materials
obsolescence, a variety of distribution methods will then be considered,
including the Internet, telephone, etc.
11. Will there be any new ways to read braille with the digital format?
Since 1999, NLS has been making braille books available in a digital form
through Web-Braille, a password-protected web-based service. More than 4,300
books, all NLS-produced braille magazines, and several hundred music scores
can be downloaded from the Internet. Although Web-Braille is a digital
format, the files were created to be embossed on braille paper and don't
contain information that would assist the user in easily navigating a book.
However, a more flexible braille reading experience may be provided by the
digital talking-book format. With a properly equipped player and a digital
talking book that includes the full text of the book, reading and navigating
the book in braille will be possible. NLS will produce only a limited
number of digital talking books that include a full text file. Nevertheless,
the presence of the text file will greatly increase the usefulness of some
titles, making cookbooks or reference books, for
example, easier to read and richer sources of information.
12. What can I do to help?
There will be many opportunities over the next few years for talking-book
users to participate in field trials evaluating various features and user
interfaces of prototype playback equipment. As field trial dates are
established, talking-book users will be recruited for participation.
The above answers to frequently asked questions reflect current NLS
understanding and planning for digital talking-book technology. Wording of
answers does not represent a technical explanation. Such details are found
in documents listed on the NLS web site <www.loc.gov/nls>.
