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Digital Talking Books, Planning for the Future

July 1998

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Planning for the Future


Today the rapid pace of technological change forces all of us to alter the way we think, act, and see the world. In the domain of library service to print-handicapped people, incredible advances in computing and communications are making possible many tools and techniques to access information that were unthinkable just a few years ago. But the pace of change and the bewildering array of possible technological solutions make it difficult for agencies serving this population to know what course to chart. We at the National Library Service for the Blind and Physically Handicapped (NLS) are trying to discern the most promising path to the digital future.

Key Factors in the Design of the NLS System

Five elements drive the design of the NLS program and affect any changes that may be considered. Some elements have a legal basis, others are long-standing policies, but all are core concepts that shape our planning for the future. The elements are these:

Planning for Transition to a Digital System

NLS has made three assumptions in planning for the next- generation talking book system.

  1. Our first assumption is that the next system will be digitally based. Not only are analog systems declining in use, but digital systems offer a number of potential advantages over analog systems:
  2. Our second assumption is that the current 4-track, 15/16-ips cassette system will be in use for at least another five to ten years. Eventually, we expect that a declining market for cassettes will lead to higher costs for cassettes, playback unit components, and duplication equipment and supplies. Simultaneously, the cost of digital system components will be dropping. However, we do not expect to see significant cost advantages for digital applications for at least five to ten years.
  3. Our third and final assumption is that we will have to use a standard or slightly modified version of a widely used consumer product or technology to gain the cost benefits of mass production. We do not have a large enough market or sufficient research dollars to pursue a technology that is out of the mainstream.

Given these assumptions, how do we get from where we are to where we want to be? Such a conversion is a complex undertaking. When NLS changed its delivery medium from phonograph records to cassettes, only the medium, its mailing container, and its playback device were replaced during the transition; otherwise, the system stayed the same. Now we are planning a change that will certainly affect many aspects possibly every aspect of our talking- book system, from recording through distribution. Very little in our current system will remain unchanged. We should not underestimate the complexity or difficulty of such an undertaking.

NLS has identified twenty tasks that will be required in the design and implementation of a next-generation talking-book system. Following is a discussion of the eleven tasks in the design phase; the nine tasks in the implementation phase will be discussed in a later section.

Design-Phase Tasks

Task 1: Define and prioritize digital talking-book (DTB) features

The starting point in the design process should be the users, who must define what they want in the next generation of talking books. NLS has begun this process in conjunction with the Canadian National Institute for the Blind (CNIB), Recording for the Blind and Dyslexic (RFB&D), the DAISY Consortium, and many other groups, working under the auspices of NISO, the National Information Standards Organization. NISO is a standards-creating body in the United States, accredited by the American National Standards Institute (ANSI) organization.

Members of the NISO committee on DTBs met first in May 1997 and have continued to meet regularly. Outcomes of these meetings will include a standard describing the file specification for a DTB, which will ensure that agencies recording talking books in accordance with the file specification will be able to read each others' books on standards-compliant playback equipment. Other products of the NISO process will include technical reports that list and prioritize the desired features in digital talking books and talking-book players and describe the production steps necessary to implement those book features. Draft standards and technical reports are due in November 1998, with final versions following perhaps a year after that.

Task 2: Simulate a DTB using a personal computer

This task will allow NLS to test patron interest in different features and experiment with various ways of implementing them before proceeding too far into the development process. By linking easily modifiable control panels to the PC, we will also be able to test different user interfaces. In order to control risks such as rapid obsolescence and high cost, we propose to build several simulations based on different software approaches.

Task 3: Develop a computer-based life-cycle cost-analysis tool for the NLS system and candidate digital systems

We see this tool as critical to assessing the economic viability of different DTB options. Because a talking-book program is a complex service with many interrelated parts, one must look at the whole system when making cost comparisons. We plan to develop a spreadsheet-based cost model that will allow easy comparison of different approaches or combinations of approaches. Feeding into the model will be historical costs from our current system as well as cost projections based on forecasts of long-term trends.

Task 4: When the book simulation is stable, make it available to evaluators worldwide

Feedback from evaluators will be used to produce software modifications. In addition, software must be developed to test candidate DTB systems for compliance with the NISO standard.

Task 5: Design and build a prototype digital collection-accessing and -archiving system

This archiving system is the heart of the DTB system. Once fully implemented, it will contain the entire digitized content of our talking-book holdings, approximately 140 terabytes of data. It must contain capabilities for long- term archiving as well as supplying DTB files for production, if we choose to use a physical medium, and for distribution, if we opt to disseminate audio books via a telecommunications channel. Software must also be created to convert current analog recordings into NISO-compliant digital files.

Task 6: Select an acceptable copyright protection system

As mentioned earlier, U.S. copyright law requires that NLS limit access to its materials to eligible users. Authors and publishers are concerned that our books and magazines will be disseminated to the sighted community, possibly damaging the market for commercial print or audio materials. Once we enter the digital domain, such dissemination will become increasingly likely, so we will need to build in adequate safeguards.

Task 7: Design or select digital mastering and playback systems

Based on the results of the NISO process, NLS will design or, if a suitable system is available, select a digital recording system capable of implementing the features identified by NISO participants. While most of NLS's books are recorded in professional studios under contract, many books and magazines produced by our network libraries are done in small studios with very limited budgets. NLS will need to ensure that these studios have the tools they will need to work in the digital domain. NLS must also develop software to allow users to play a DTB based on the playback features specified in the NISO standard. This software must be compatible with multiple platforms. Finally, NLS will establish a facility for maintaining the many pieces of software developed for the DTB.

Task 8: Examine distribution methods from a systems perspective, focusing on cost and convenience

NLS will develop a variety of designs for distribution systems, including electronic systems that deliver books and magazines directly to patrons from regional or national centers as well as mail-based systems that deliver a physical medium to the patron. Cost issues will address national and regional production, playback units, storage, packaging, distribution, and other concerns. In focusing on convenience, NLS will consider ease of system operation and use by patrons, librarians, machine-lending agencies, volunteer producers, and international borrowers. Using the cost-analysis tool described in task 3, NLS will develop a written comparison of the different distribution options, identifying the most promising candidates.

Task 9: Select players that best express the features in the NISO digital talking-book standard

Wherever feasible, NLS will use components of popular entertainment hardware to assure cost control and user acceptance. NLS will design and test user interfaces incorporating the features specified in the NISO standard.

Task 10: Build multiple prototypes

To minimize risk, NLS will build and evaluate several different prototypes and allow users to evaluate them. Subsequently, prototypes will be evaluated to assess their effect on the operations of regional libraries, machine- lending agencies, the U.S. Postal Service, manufacturers, and repair organizations.

Task 11: Design and implement prototype testing to determine life-cycle cost

NLS staff will predict the theoretical reliability of playback units and test them for actual performance, thereby identifying vulnerable components. A maintenance plan will be written, specifying which components can be repaired, which must be replaced, and the range, depth, positioning, and value of spare parts. Finally, NLS will predict the life-cycle cost of each prototype and forecast the payback point for NLS using the cost model developed in task 3. These design-phase tasks represent only an overview of the process of moving to a digitally based talking-book system. Although the tasks are listed sequentially, many will proceed in a parallel fashion. Furthermore, these tasks address only the process of designing a DTB system. Implementation issues are addressed in a later section of this document.

Timing of Introduction of NLS Digital Talking Books

There is a great deal of work underway around the world focused on bringing digital talking books to blind readers. Some projects are already producing DTBs, while others plan to begin delivering books before the end of the decade. NLS, in contrast, does not foresee full implementation of a DTB system for five to ten years. Why is that?

Earlier, we discussed a few of the benefits DTBs will bring to readers. While several features, such as improved sound quality and decreased manipulation of the playback media, will be useful to all patrons, they are marginal improvements that by themselves do not justify a major change in technology. The most significant improvements, such as enhanced navigation and text-related features, will mostly benefit the more sophisticated users and the more complex books that is, students reading textbooks. While some NLS users and books are in the category that will gain from the use of a digital system, most patrons and books will see only moderate improvements. For this reason, NLS is less motivated to change in the near future than are other agencies that serve primarily students.

Furthermore, we are not currently aware of a medium or a delivery system that is low enough in cost or that offers enough advantages over our current system to justify a change. As an example, let us discuss the pros and cons of a CD-ROM-based delivery system, the most viable current option.

Considering the uncertain life span of CD-ROM technology and its higher maintenance costs, we project the life-cycle costs of a CD-ROM-based system to be significantly higher than those of our current system. Other candidate delivery systems suffer similar drawbacks when compared to the present cassette-based system. Therefore, it seems prudent to continue using 4-track cassettes until a better alternative is identified.


Moving from our current system to a digital one will be a challenging and exciting process. In a recent article, Robert Lucky, vice president for applied research at Bellcore, formerly Bell Labs, highlighted the difficulties of planning during this time of rapid change. "Moore's law," he said (referring to the pattern in computer technology of constantly increasing power at a decreasing cost), "guarantees that technologies become obsolete and that economics become overturned at a rate that is incompatible with most infrastructure planning and financing." This is a frightening statement for those of us with large inventories of equipment. It forces us immediately to confront complexity and risk. Because our users are a very diverse and widely dispersed population with special needs and evolving expectations, our service is intrinsically complex. Risk is inherent in building a future based on technologies that have continuously changing capabilities and costs.

The key to handling complexity will be to separate the production process and the product into parts that are manageable, replaceable, upgradeable, and extensible. For example, the software must be modular so that it can support playback systems that evolve and users who have diverse preferences.

The key to managing risk is to support as many process and product alternatives as affordable. There is considerable uncertainty regarding which technologies will be most affordable and popular, especially when major investments are being initiated. Sponsoring several approaches through prototyping and field testing permits expensive decisions to be made with more confidence.

Certainly this will be an exciting process. As digital talking-book systems are brought into being, they will bring a great range of benefits to blind and physically handicapped readers. Many of the marvelous capabilities of the printed book will be combined with the power of computers to create a tool of unprecedented flexibility and power. We look forward to making this tool a reality.

John Cookson, Head, Engineering Section
Michael M. Moodie, Research and Development Officer

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prologue --- planning --- NISO --- activity planning --- 20 steps --- 9 tasks --- consumer involvement

bibliography --- appendix i: details in implementation --- appendix ii: overview of contracting approach

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Posted on 2013-06-28