848 lines
39 KiB
Plaintext
848 lines
39 KiB
Plaintext
Linux Accessibility HOWTO
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Michael De La Rue
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Sharon Snider
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v3.1, June 21, 2002
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Revision History
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Revision v3.1 2002-06-21 Revised by: sds
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Updated and converted to DocBook XML.
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Revision v3.0 2001-10-25 Revised by: sds
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Updated and converted to DocBook SGML.
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Revision v2.11 1997-03-28 Revised by: mdlr
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Last Linuxdoc revision.
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The Linux Accessibility HOWTO covers the use of adaptive technologies that
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are available for the Linux operating system, as well as the software
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applications and hardware devices that can be installed to make Linux
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accessible to users with disabilities. The information provided targets
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specific groups of individuals with similar disabilities.
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-----------------------------------------------------------------------------
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Table of Contents
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1. Introduction
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1.1. Distribution Policy
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2. The Linux Operating System
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2.1. Assistive Technologies Available for Linux
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2.2. Usability
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3. Visual Impairments
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3.1. Technologies for the Visually Impaired
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4. Hearing Impaired
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4.1. Assistive Technologies for the Hearing Impaired
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5. Physically Disabled
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5.1. Keyboard Navigation
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5.2. Assistive Technologies for the Physically Disabled
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5.3. Additional Resources
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6. Cognitive, Language, and Other Impairments
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6.1. Assistive Technologies for Cognitive, Language and Other Impairments
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7. Developing Accessible Applications
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8. Other Helpful Information
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9. Acknowledgments
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1. Introduction
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The purpose of this HOWTO is to introduce the tools, applications, and
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configuration utilities that are available to Linux users who are disabled.
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The information provided targets groups of individuals with the following
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disabilities:
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* Visually Impaired
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* Hearing Impaired
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* Physically Disabled
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* Cognitive, Language, and Other Impairments
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Please send any comments, or contributions via e-mail to [mailto:
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snidersd@us.ibm.com] Sharon Snider. This document will be updated regularly
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with new contributions and suggestions.
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-----------------------------------------------------------------------------
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1.1. Distribution Policy
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The Access-HOWTO may be distributed, at your choice, under either the terms
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of the GNU Public License version 2 or later or the standard Linux
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Documentation Project (LDP) terms. These licenses should be available from
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the LDP Web site: [http://www.linuxdoc.org/docs.html] http://www.linuxdoc.org
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/docs.html. Please note that since the LDP terms do not allow modification
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(other than translation), modified versions can be assumed to be distributed
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under the GPL.
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ViaVoice® is a registered trademark of International Business Machines
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Corporation.
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-----------------------------------------------------------------------------
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2. The Linux Operating System
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The Linux operating system has many software applications and utilities that
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run in the non-graphical environment. The graphical user interface (GUI),
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which is often referred to as X Windows, is clearly separate from the
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underlying non-graphical, text-only environment. One major reason that a
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visually impaired individual can use Linux is that network connectivity is
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built in to the operating system and provides full access to the Internet
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from the non-graphical interface. All visible text on the screen can be
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translated using a screen reader and speech synthesizer.
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Over the past few years many improvements have been made to the GUI, and many
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of the desktops now provide features and enhancements designed for
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accessibility. In the following sections you will find information on the
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tools, utilities, and applications that are available to assist users in
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configuring their desktop environment.
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-----------------------------------------------------------------------------
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2.1. Assistive Technologies Available for Linux
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Assistive technologies are computer hardware devices and software
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applications that provide individuals with impairments access to the
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information and applications on a computer. Although there are not many
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commercial applications available specifically for Linux accessibility, there
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are free software applications that can make the computer more accessible.
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Detailed information on assistive technologies that are available has been
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listed in this document based on the type of disability.
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-----------------------------------------------------------------------------
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2.2. Usability
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Linux has the advantage over Windows that a large majority of Linux software
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has been developed for the console. Although many programs are now being
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developed for the GUI, programs continue to be written for the non-graphical,
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text-based environment. Linux originated as a programmer's operating system
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and, for the physically disabled, this means that it is easy to build and
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customize programs to suit an individual's needs.
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The windowing system used by Linux (X11) includes many programming tools that
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enable further modification and customization of the GUI. KDE and GNOME have
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included many accessibility and usability features in their latest releases
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and are continuing to test, upgrade, and enhance the graphical environment.
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The following are links to KDE and GNOME's accessibility and usability
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projects:
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* KDE Accessibility Project - [http://accessibility.kde.org/] http://
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accessibility.kde.org/.
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* GNOME Accessibility Project - [http://developer.gnome.org/projects/gap/]
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http://developer.gnome.org/projects/gap/.
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* KDE Usability Project - [http://usability.kde.org/] http://
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usability.kde.org/.
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* GNOME Usability Project - [http://developer.gnome.org/projects/gup/]
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http://developer.gnome.org/projects/gup/.
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-----------------------------------------------------------------------------
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3. Visual Impairments
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There are two categories of visual impairments. Individuals who are partially
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sighted (for example, blurred vision, near and far-sightedness, color
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blindness) and those who are totally blind. Assistive technologies are
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available for the Linux operating system for visually impaired users, and
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many of the software packages are free.
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-----------------------------------------------------------------------------
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3.1. Technologies for the Visually Impaired
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The following is a list of assistive technologies for visually impaired
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users:
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-----------------------------------------------------------------------------
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3.1.1. Screen Readers
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Screen readers are software applications that are installed on the computer
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to provide translation of the information on the computer screen to an audio
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output format. The translation is passed to the speech synthesizer and the
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words are spoken out loud. Currently, fully functional screen readers are
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only available for Linux in console mode. This section describes some of the
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most common screen readers.
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* Emacspeak is the complete Audio Desktop is an excellent non-graphical,
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text based interface for users who are visually impaired. This
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application can be used as a screen reader in conjunction with a hardware
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synthesizer or IBM ViaVoice® Run-time text-to-speech application. More
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information and software packages of are available at: [http://
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www.cs.cornell.edu/home/raman/emacspeak/] http://www.cs.cornell.edu/home/
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raman/emacspeak/. The Emacspeak HOWTO [http://www.ibiblio.org/pub/Linux/
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docs/HOWTO/] http://www.ibiblio.org/pub/Linux/docs/HOWTO/ includes a
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tutorial and installation guide.
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* Jupiter Speech System is a screen reader for Linux in console mode. A
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user guide and software packages are available at: [http://www.eklhad.net
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/linux/jupiter/] http://www.eklhad.net/linux/jupiter/.
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* Screader is a screen reader for Linux in console mode that works with the
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Festival software speech synthesizer and the Accent hardware synthesizer.
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Information and downloads are available at: [http://www.euronet.nl/~acj/
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eng-screader.html] http://www.euronet.nl/~acj/eng-screader.html.
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* Speaker is a new plugin for the Konqueror file manager and Web browser.
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Speaker provides Text to Speech using the Festival speech system or IBM
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ViaVoice. Downloads are available at: [http://dogma.freebsd-uk.eu.org/
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~grrussel/speaker.html] http://dogma.freebsd-uk.eu.org/~grrussel/
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speaker.html.
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* Speakup is a screen review package for the Linux operating system. It
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requires a hardware speech synthesizer, such as the DecTalk Express. An
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installation boot disk and packages are available at: [http://
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www.linux-speakup.org/] http://www.linux-speakup.org/ that allow a
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visually impaired user to install the Linux operating system.
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* ZipSpeak is a talking mini-distribution of Linux. More information and
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software packages are available at: [http://www.linux-speakup.org/
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zipspeak.html] http://www.linux-speakup.org/zipspeak.html.
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-----------------------------------------------------------------------------
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3.1.2. Speech Synthesizers
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Speech synthesizers can be a hardware device or a text to speech (TTS)
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software application that creates the sounds necessary to provide speech
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output. Hardware synthesizers are available for the Linux operating system;
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however, they can be very expensive and must be compatible with the screen
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reader application in order to function properly. The alternative is to
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download and install a software synthesizer such as IBM's ViaVoice or
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Festival and configure the application to a compatible screen reader, such as
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Emacspeak.
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-----------------------------------------------------------------------------
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3.1.2.1. Hardware Speech Synthesizers
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A hardware speech synthesizer is a device that is connected to the computer's
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serial or parallel port and translates the text to a spoken output. Normally
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there are Braille labels on all controls to indicate the off and on position,
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and volume control. Hardware synthesizers also have the ability to speak in
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different tones that can be setup to indicate various parts of a document or
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text. Some models will provide a connection for headphones. The following is
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a list of speech synthesizers that are supported on the Linux operating
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system and can be used with Emacspeak:
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* Accent SA and Apollo 2 ([http://polio.dyndns.org/chip/vss.html] http://
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polio.dyndns.org/chip/vss.html)
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* DECTalk Express ([http://www.4access.com/synthesizers.asp] http://
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www.4access.com/synthesizers.asp)
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* DoubleTalk ([http://www.rcsys.com] http://www.rcsys.com)
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-----------------------------------------------------------------------------
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3.1.2.2. Software Speech Synthesizers
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A software speech synthesizer is an application that translates the text on
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the screen to speech output and provides speech synthesis, so that the screen
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reader application can read information out loud to the user.
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* Festival is a general, multi-lingual speech synthesis system developed at
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the Center for Speech Technology Research (CSTR). It offers a full TTS
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system with various application program interfaces, as well as an
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environment for development and research of speech synthesis techniques.
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Mbrola or FestVox are needed to complete the Festival installation.
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Software packages and installation instructions are available at: [http:/
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/www.cstr.ed.ac.uk/projects/festival/] http://www.cstr.ed.ac.uk/projects/
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festival/.
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* Mbrola is a speech synthesizer that can be used with a TTS application,
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such as, Festival to provide speech output. More information is available
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at: [http://tcts.fpms.ac.be/synthesis/mbrola.html] http://tcts.fpms.ac.be
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/synthesis/mbrola.html.
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-----------------------------------------------------------------------------
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3.1.3. Screen Magnifiers
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Screen magnifiers enable users that are partially sighted to view selected
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areas of the screen in a manner similar to using a magnifying glass.
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* GMag is a screen magnifier for X Windows. It provides continuous
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magnification while you work, as well as the option to change the
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contrast of images at run-time. More information and downloads are
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available at: [http://projects.prosa.it/gmag/] http://projects.prosa.it/
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gmag/.
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* Puff is a screen magnifier for users who need a high magnification of
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text and graphics in X Windows. Puff follows the focus of the mouse or
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pointer and enlarges the portion of the screen under the cursor. In order
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for Puff to run properly on Linux the source code needs to be modified.
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This application is not a good option for inexperienced users. The
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software packages and source code modification instructions are available
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at: [http://trace.wisc.edu/world/computer_access/unix/unixshare.html]
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http://trace.wisc.edu/world/computer_access/unix/unixshare.html.
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* SVGATextmode enlarges or reduces the font size for users who perfer to
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work in console mode. The normal text screen that Linux provides is 80
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characters across and 25 vertically. After SVGATextmode is installed, the
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text can be displayed much larger. One example would be 50 characters
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across and 15 vertically. The program does not offer the ablitity to zoom
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in and out, but the user can re-size when necessary. The most current
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download is available at: [http://freshmeat.net/projects/svgatextmode/]
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http://freshmeat.net/projects/svgatextmode/. Do not run try to run
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SVGATextmode from an X Windows terminal. You must be in console mode for
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the display to function properly.
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* UnWindows is a collection of programs that includes Dynamag, a screen
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magnification program that helps the user locate the mouse pointer. The
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source code is available for Dynamag as a stand alone application, or the
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entire UnWindows package can be downloaded at: [http://www.cs.rpi.edu/pub
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/unwindows/] http://www.cs.rpi.edu/pub/unwindows/. The entire UnWindows
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package will not work with Linux without programming modifications.
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However, the Dynamag application can be installed successfully without
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any additional code changes.
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* Xzoom is a screen magnifier similar to Xmag that allows the user to
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magnify rotate or mirror a portion of the screen. The most current
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download is available at: [http://filewatcher.org/sec/xzoom.html] http://
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filewatcher.org/sec/xzoom.html.
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-----------------------------------------------------------------------------
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3.1.4. Adjusting the Screen's Resolution
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The X Windows server can be setup with different screen resolutions. The
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ability to adjust the screen's resolution allows a partially sighted user to
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magnify the screen with a single key sequence. The steps to set up your
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system are as follows:
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1. Changed directories, type cd /etc
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2. Using a text editor, open the XF86Config file
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3. Locate the line beginning with Modes and change it to
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Modes "1280x1024" "1024x768" "800x600" "640x480" "320x240"
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Note: The settings may vary based your monitor's highest resolution mode.
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4. Save the file and exit.
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To enlarge the text on the screen type Ctrl+Alt+keypad-plus and to make the
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text smaller type Ctrl+Alt+keypad-minus
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-----------------------------------------------------------------------------
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3.1.5. Braille Devices
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Braille terminals are normally used by individuals who are totally blind and
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may be hearing impaired as well. A Braille display uses a series of pins to
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form Braille symbols that are continuously updated as the users changes
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focus. A Braille embosser is a hardware device for printing a hard copy of a
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text document in Braille. Braille translation software is required to
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translate the on-screen text to a Braille format.
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-----------------------------------------------------------------------------
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3.1.5.1. Braille Hardware Devices
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The following Braille devices have been listed on the hardware compatibility
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list of one or more of the following Braille translation applications:
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* Braillex [http://www.redhat.com/mailing-lists/blinux-announce/
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msg00031.html] http://www.redhat.com/mailing-lists/blinux-announce/
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msg00031.html.
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* Alva B.V.: ABT3xx, Delphi (serial and parallel ports), Satellite. .
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* Baum: Vario/RBT 40/80 (emulation 1/2) [http://www.baum.de/English/
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homeeng1.htm] http://www.baum.de/English/homeeng1.htm.
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* Blazie Engineering: BrailleLite 18/40 [http://www.freedomscientific.com/
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index.html] http://www.freedomscientific.com/index.html.
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* Handialog: VisioBraille 2040 [http://www.handialog.com/indexuk.htm] http:
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//www.handialog.com/indexuk.htm.
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* Handy Tech Elektronik GmbH: BrailleWave, mod20, mod40, mod80 [http://
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www.handytech.de/] http://www.handytech.de/.
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* MDV: MB208/MB408L/MB408S (protocol 5) [http://www.cavazza.it/cnt/schede/
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scheda-mb408l-eng.html] http://www.cavazza.it/cnt/schede/
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scheda-mb408l-eng.html.
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* Pulse Data International: BrailleNote 18/32 [http://www.pulsedata.co.nz/
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graphics.htm] http://www.pulsedata.co.nz/graphics.htm.
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* Telesensory Systems Inc.: Navigator 20/40/80 (latest firmware version
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only), PowerBraille 40/65/80 [http://www.telesensory.com/] http://
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www.telesensory.com/.
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* Tieman B.V.: CombiBraille 25/45/85, MiniBraille 20, MultiBraille MB125CR/
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MB145CR/MB185CR [http://www.braillevoyager.nl/uk/index.html] http://
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www.braillevoyager.nl/uk/index.html.
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* Tiflosoft: VideoBraille 40 [http://www.tinlecco.it/tiflosoft/] http://
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www.tinlecco.it/tiflosoft/.
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-----------------------------------------------------------------------------
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3.1.5.2. Braille Translation Software
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The following Braille translation applications are available for download:
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* Brass is a new program that combines speech and Braille output. The
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current version is still in testing and can be downloaded at: [http://
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www.butenuth.onlinehome.de/blinux/] http://www.butenuth.onlinehome.de/
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blinux/.
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* BrLTTY supports parallel port and USB Braille displays and provides
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access to the Linux console. It drives the terminal and provides complete
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screen review capabilities. It is available at: [http://dave.mielke.cc/
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brltty/] http://dave.mielke.cc/brltty/.
|
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* NFBTrans is a freeware Braille translator written by the National
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Federation for the Blind (NFB). Software packages are available for
|
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download at: [http://www.nfb.org/nfbtrans.htm] http://www.nfb.org/
|
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nfbtrans.htm.
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-----------------------------------------------------------------------------
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3.1.6. Cursors for X Windows
|
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|
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Changing the shape and size of the mouse cursor can help users who have a
|
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problem following or seeing the cursor. The X Big Cursor mini HOWTO explains
|
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how to configure enlarged mouse cursors with the X Windows system. This HOWTO
|
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is available at: [http://www.icewalk.com/doclib/howtos/mini/
|
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X-Big-Cursor.html] http://www.icewalk.com/doclib/howtos/mini/
|
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X-Big-Cursor.html.
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There are also a large select of cursors that can be downloaded at: [http://
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themes.tucows.com/cursors.html] http://themes.tucows.com/cursors.html.
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-----------------------------------------------------------------------------
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3.1.7. Audio
|
||
|
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Audio can be very useful to users who are visually impaired. In most X
|
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Windows desktop environments audio alerts and sound events can be setup
|
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within the desktop control center by enabling sound and verifying that the
|
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option to show sound is activated. You will need to check the desktop users
|
||
manual for setup and configuration of sound events.
|
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Locktones is an excellent application for providing toggle keys that sound an
|
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audio alert to warn the user that a keystroke has created a locking state
|
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such as Cap Locks, or Num Locks. The application can be downloaded at: [http:
|
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//leb.net/pub/blinux/] http://leb.net/pub/blinux/.
|
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|
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Linux can also be configured to beep at the login prompt so the user knows
|
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when to type in the password. A configuration utility can be downloaded and
|
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installed that can provide this function at: [http://leb.net/pub/blinux/
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bootmeup/] http://leb.net/pub/blinux/bootmeup/.
|
||
-----------------------------------------------------------------------------
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3.1.8. Additional Resources
|
||
|
||
* Access Mozilla has a goal to build an accessible Web suite: browser,
|
||
e-mail, news, composer and chat that conform to the W3C accessibility
|
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standards. More information is available at: [http://
|
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access-mozilla.sourceforge.net/] http://access-mozilla.sourceforge.net/.
|
||
|
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* Blind + Linux = BLINUX provides documentation, downloads and a mailing
|
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list that focus on users who are blind. Information and software packages
|
||
are available at: [http://leb.net/blinux] http://leb.net/blinux.
|
||
|
||
* LaTex/Tex is an extremely powerful document preparation system and it can
|
||
be used to produce large print documents. More information is available
|
||
at: [http://www.emerson.emory.edu/services/latex/latex_toc.html] http://
|
||
www.emerson.emory.edu/services/latex/latex_toc.html.
|
||
|
||
* National Federation for the Blind's (NFB) purpose is to help blind
|
||
persons achieve self-confidence and self-respect and to act as a vehicle
|
||
for collective self expression by the blind. Information for blind users,
|
||
as well as software are available at: [http://www.nfb.org/] http://
|
||
www.nfb.org/.
|
||
|
||
* Project Ocularis is run by volunteers, and the project's aim is to
|
||
improve Linux accessibility through the creation of new free software and
|
||
the modification of pre-existing free software. More information is
|
||
available at: [http://ocularis.sourceforge.net] http://
|
||
ocularis.sourceforge.net.
|
||
|
||
* Screen is a standard piece of software that allows many different
|
||
applications to run at the same time on a single terminal in console
|
||
mode. Screen has been enhanced to support some Braille terminals
|
||
directly. It is available for download at: [http://www.icewalk.com/
|
||
softlib/app/app_01508.html] http://www.icewalk.com/softlib/app/
|
||
app_01508.html.
|
||
|
||
* SuSE Linux is the first Linux distribution to support installation of the
|
||
Linux operating system and applications that run on Linux in Braille. The
|
||
Blinux screen reader runs in the background to enable visually impaired
|
||
users to work in a Linux console environment. More information is
|
||
available at: [http://www.suse.de/us/products/susesoft/70news/
|
||
new_in_70.html] http://www.suse.de/us/products/susesoft/70news/
|
||
new_in_70.html.
|
||
|
||
* xocr is an optical character recognition program that scans written text,
|
||
such as a book and translates it to audio output, so the information is
|
||
available to visually impaired users. More information is available at:
|
||
[http://sal.unimedya.net.tr/Z/3/XOCR.html] http://sal.unimedya.net.tr/Z/3
|
||
/XOCR.html.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
4. Hearing Impaired
|
||
|
||
For users who have hearing impairments the audio output must be conveyed
|
||
visually on the screen. Most desktops provide visual audio alerts and
|
||
warnings. In console mode the system can also be configured to provide visual
|
||
bells. There is a "Visual Bells mini-HOWTO" written by Alessandro Rubini that
|
||
provides the configuration details available at: [http://www.ibiblio.org/pub/
|
||
Linux/docs/HOWTO/mini/] http://www.ibiblio.org/pub/Linux/docs/HOWTO/mini/.
|
||
-----------------------------------------------------------------------------
|
||
|
||
4.1. Assistive Technologies for the Hearing Impaired
|
||
|
||
The following is a list of assistive technologies for the hearing impaired:
|
||
-----------------------------------------------------------------------------
|
||
|
||
4.1.1. Telecommunications Devices for the Deaf (TDD)
|
||
|
||
TDD allows for the user you to communicate over the telephone using the
|
||
computer as a text terminal.
|
||
|
||
* Zapata is a computer-based, high-density telephony project. The current
|
||
version is available for download as source code on at: [http://
|
||
www.zapatatelephony.org/project.html] http://www.zapatatelephony.org/
|
||
project.html.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
4.1.2. Closed Captioning
|
||
|
||
Closed captioning provides text translation of spoken words to video display.
|
||
Closed captioning can be used for distance learning, video-teleconferencing,
|
||
audio from a CD-ROM, and other types of interactive technology.
|
||
|
||
* Ccdecoder is a closed captioned, extended data services decoder for the
|
||
bttv and video4linux based tv video cards: [http://sourceforge.net/
|
||
projects/ccdecoder/] http://sourceforge.net/projects/ccdecoder/.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
5. Physically Disabled
|
||
|
||
There are a wide range of physical disabilities that can impair a user's
|
||
mobility, and many of these impairments need to be addressed on an individual
|
||
basis. This section addresses impairments that apply to users who have
|
||
difficulty using a mouse, pointing device, or keyboard.
|
||
-----------------------------------------------------------------------------
|
||
|
||
5.1. Keyboard Navigation
|
||
|
||
There are features that are built into the Linux operating system that allow
|
||
for additional keyboard configuration. In some of the X Windows desktops
|
||
these settings can be changed from the control center. An application has
|
||
also been developed for X Windows called AccessX and it provides a graphical
|
||
user interface for configuring all the AccessX keyboard settings. These
|
||
settings are:
|
||
|
||
* StickyKeys enable the user to lock modifier keys (for example, control
|
||
and shift) allowing single finger operations in place of multiple key
|
||
combinations.
|
||
|
||
* MouseKeys provide alternative keyboard sequences for cursor movement and
|
||
mouse button operations.
|
||
|
||
* SlowKeys requires the user to hold the key down for a specified period of
|
||
time before the keystroke is accepted. This prevents keystrokes that are
|
||
pressed by accident from being sent.
|
||
|
||
* ToggleKeys sound an audio alert that warns the user that a keystroke
|
||
created a locking state for keys, such as Caps Lock, and Num Lock.
|
||
|
||
* RepeatKeys allow a user with limited coordination additional time to
|
||
release keys before multiple key sequences are sent to the application.
|
||
|
||
* BounceKeys or Delay Keys have a delay between keystrokes. This function
|
||
can help prevent the system from accepting unintentional keystrokes.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
5.2. Assistive Technologies for the Physically Disabled
|
||
|
||
The following is a list of assistive technologies for the physically
|
||
disabled:
|
||
-----------------------------------------------------------------------------
|
||
|
||
5.2.1. On-Screen Keyboard
|
||
|
||
On-screen keyboards enable a user to select keys using a pointing device,
|
||
such as a mouse, trackball, or touch pad. This application can be used in
|
||
place of a standard keyboard.
|
||
|
||
* GTkeyboard is a on-screen, graphical keyboard and can be downloaded at:
|
||
[http://opop.nols.com/gtkeyboard.html] http://opop.nols.com/
|
||
gtkeyboard.html.
|
||
|
||
* GNOME Onscreen Keyboard (GOK)is a on-screen, graphical keyboard that
|
||
enables users to control their computer without having to rely on a
|
||
standard keyboard or mouse. MOre information is available at [http://
|
||
www.gok.ca] http://www.gok.ca.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
5.2.2. Speech Recognition
|
||
|
||
Speech recognition utilities are used by people with mobility impairments, so
|
||
they can operate the computer using voice control.
|
||
|
||
* Open Mind Speech is a development project for speech recognition tools
|
||
and applications. Information for the project and a mailing list are
|
||
available at: [http://freespeech.sourceforge.net/] http://
|
||
freespeech.sourceforge.net/.
|
||
|
||
* ViaVoice Dictation for Linux allows you to write documents using your
|
||
voice rather than a keyboard. Information and downloads are available at:
|
||
[http://www-4.ibm.com/software/speech/dev/] http://www-4.ibm.com/software
|
||
/speech/dev/.
|
||
|
||
* This site has information and links related to several different speech
|
||
recognition utilities. [http://www.trace.wisc.edu/world/computer_access/
|
||
unix/unixshar.html] http://www.trace.wisc.edu/world/computer_access/unix/
|
||
unixshar.html.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
5.3. Additional Resources
|
||
|
||
The following is a list of additional Web sites that may be of interest to
|
||
users with mobility impairments:
|
||
|
||
* This site provides a kernel patch that can be downloaded to enable a
|
||
one-handed keyboard. The download is available at: [http://
|
||
www.fourtytwo.de] http://www.fourtytwo.de.
|
||
|
||
* Configuration and information on Adapting the Linux Keyboard for a one
|
||
handed user is available at: [http://www.eklhad.net/linux/app/
|
||
onehand.html] http://www.eklhad.net/linux/app/onehand.html.
|
||
|
||
* Morseall allows the user to control a Linux shell by tapping Morse code
|
||
on the left mouse button: [http://sourceforge.net/projects/morseall]
|
||
http://sourceforge.net/projects/morseall.
|
||
|
||
* The keyboard and console HOWTO provides additional keyboard configuration
|
||
information. [http://www.ibiblio.org/pub/Linux/docs/HOWTO/
|
||
Keyboard-and-Console-HOWTO] http://www.ibiblio.org/pub/Linux/docs/HOWTO/
|
||
Keyboard-and-Console-HOWTO.
|
||
|
||
* There is a Speech Recognition HOWTO, written by Stephen Cook that
|
||
provides complete details for anyone interested in learning more about
|
||
speech recognition applications. [http://www.linuxdoc.org/HOWTO/] http://
|
||
www.linuxdoc.org/HOWTO/.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
6. Cognitive, Language, and Other Impairments
|
||
|
||
Cognitive and language impairments include dyslexia and problems with;
|
||
memory, comprehension, problem solving, and written language. For many
|
||
individuals with cognitive and language disabilities, complex graphical
|
||
displays and inconsistent use of words can make using the computer more
|
||
difficult. A user with epilepsy can have a seizure from an application with
|
||
blinking lights and animation. Most desktops now allow users to disable
|
||
animation. Web browsers such as Mozilla and Netscape allow users to disable
|
||
graphics. It is important to check the documentation for preferences that are
|
||
available in the desktop environment you are using, as well as any
|
||
applications that are used. This section discusses the tools that are
|
||
available to aid users with these impairments:
|
||
-----------------------------------------------------------------------------
|
||
|
||
6.1. Assistive Technologies for Cognitive, Language and Other Impairments
|
||
|
||
The following is a list of assistive technologies that can be helpful to
|
||
users with cognitive, language, and other impairments:
|
||
-----------------------------------------------------------------------------
|
||
|
||
6.1.1. Screen Readers and Speech Synthesis
|
||
|
||
Screen readers with speech synthesis enable the system to read on-screen
|
||
information and text out loud to the user. This type of assistive technology
|
||
can be particularly helpful to individuals who have dyslexia and other
|
||
learning disabilities. Although there are no screen readers available for the
|
||
GNOME desktop, screen reader applications are available for Linux in console
|
||
mode that provide this functionality.
|
||
|
||
* Emacspeak is a speech interface that will provide audio output for all
|
||
text. The program works in terminal and console mode and requires a
|
||
software or hardware speech synthesizer. The downloads and users manuals
|
||
are available at: [http://www.cs.cornell.edu/home/raman/emacspeak/] http:
|
||
//www.cs.cornell.edu/home/raman/emacspeak/.
|
||
|
||
* The Trace Center provides information and downloads for various screen
|
||
readers and speech synthesizers. More information is available at: [http:
|
||
//www.trace.wisc.edu/world/computer_access/unix/unixshar.html] http://
|
||
www.trace.wisc.edu/world/computer_access/unix/unixshar.html.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
6.1.2. Keyboard filters and Word Processing
|
||
|
||
Keyboard filters and word processing applications that have word prediction
|
||
and spell checking utilities can be an excellent aid for users with learning
|
||
and language impairments.
|
||
-----------------------------------------------------------------------------
|
||
|
||
6.1.3. Speech Recognition
|
||
|
||
Speech recognition applications enables you to control the computer with your
|
||
voice rather than having to type or write out the information.
|
||
|
||
* CVoice Control is a speech recognition system that enables a user to
|
||
connect spoken commands to UNIX commands. More information is available
|
||
at: [http://www.kiecza.de/daniel/linux/] http://www.kiecza.de/daniel/
|
||
linux/.
|
||
|
||
* IBM ViaVoice Dictation for Linux allows the user to write documents using
|
||
their voice rather then a keyboard and can read the information back to
|
||
the user. More information is available at: [http://www-4.ibm.com/
|
||
software/speech/dev/] http://www-4.ibm.com/software/speech/dev/.
|
||
|
||
* Open Mind Speech is a development project for speech recognition tools
|
||
and applications. The developers have established a mailing list for
|
||
asking questions and obtaining information at: [http://
|
||
freespeech.sourceforge.net/] http://freespeech.sourceforge.net/.
|
||
|
||
* XVoice enables continuous speech to text dictation for many applications.
|
||
More information is available at: [http://www.compapp.dcu.ie/~tdoris/
|
||
Xvoice/] http://www.compapp.dcu.ie/~tdoris/Xvoice/.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
7. Developing Accessible Applications
|
||
|
||
It is important to consider accessibility when developing new applications
|
||
for the Linux operating system. The American Foundation for the Blind, the
|
||
GNOME Accessibility Project, IBM, Sun, and W3C have written guidelines that
|
||
are excellent road maps for developing and testing new Linux software. The
|
||
following Web sites provide the tools, checklists and testing information to
|
||
help developers write accessible programs for impaired users.
|
||
|
||
* American Foundation for the Blind provides information on creating
|
||
accessible computer applications at: [http://www.afb.org/
|
||
info_document_view.asp?documentid=198] http://www.afb.org/
|
||
info_document_view.asp?documentid=198.
|
||
|
||
* GNOME Accessibility Project has written a guide specifically for
|
||
application development for the GNOME 2.0 desktop. More information is
|
||
available at: [http://developer.gnome.org/projects/gap/guide/gad/
|
||
index.html] http://developer.gnome.org/projects/gap/guide/gad/index.html.
|
||
|
||
* IBM Accessibility Center provides links to a software accessibility
|
||
checklist, testing information, and the Section 508 Rehabilitation Act.
|
||
This site is located at: [http://www-3.ibm.com/able/guidelines.html]
|
||
http://www-3.ibm.com/able/guidelines.html.
|
||
|
||
* Sun Accessibility provides information on designing applications for
|
||
accessibility at: [http://www.sun.com/access/developers/
|
||
software.guides.html] http://www.sun.com/access/developers/
|
||
software.guides.html and an Accessibility Quick Reference Guide is
|
||
available at: [http://www.sun.com/access/developers/
|
||
access.quick.ref.html] http://www.sun.com/access/developers/
|
||
access.quick.ref.html.
|
||
|
||
* W3C User Agent Accessibility Guidelines 1.0 provides guidelines on
|
||
accessible Web browser development including multimedia players and Web
|
||
related software. [http://www.w3.org/TR/UAAGIO/] http://www.w3.org/TR/
|
||
UAAGIO/.
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
8. Other Helpful Information
|
||
|
||
The following is a list of additional information that may be helpful, but is
|
||
not necessarily targeting a specific disability:
|
||
|
||
* The CMU Sphinx Group Source has released a set of reasonably mature,
|
||
speech components that provide a basic level of technology to anyone
|
||
interested in creating speech enabled applications. More information is
|
||
available at: [http://fife.speech.cs.cmu.edu/sphinx/] http://
|
||
fife.speech.cs.cmu.edu/sphinx/.
|
||
|
||
* Access to Linux documentation is critical to learning and using Linux.
|
||
The Linux Documentation Project has links to many Linux HOWTOs, mini
|
||
HOWTOs, and guides, as well as information on becoming involved in
|
||
authoring new HOWTOs. More information and downloads are available at:
|
||
[http://www.linuxdoc.org] http://www.linuxdoc.org.
|
||
|
||
* RPMFind.net provides rpm downloads for Linux applications on most Linux
|
||
operating systems. The site is located at:[http://www.rpmfind.net] http:/
|
||
/www.rpmfind.net.
|
||
|
||
* Sourceforge provides updated information, documentation, and software for
|
||
Linux. Some of the applications available are under development. More
|
||
information and downloads are available at: [http://www.sourceforge.net]
|
||
http://www.sourceforge.net.
|
||
|
||
* The Trace Center provides accessibility information and software for the
|
||
Linux operating system. More information is available at: [http://
|
||
trace.wisc.edu/worl/computer_access/] http://trace.wisc.edu/worl/
|
||
computer_access/ and the Linux Accessibility Resource Site (LARS) [http:/
|
||
/trace.wisc.edu/linux/] http://trace.wisc.edu/linux/.
|
||
|
||
* W3C Web Accessibility initiative provides information and links on Web
|
||
site accessibility. More information is available at: [] .
|
||
|
||
|
||
-----------------------------------------------------------------------------
|
||
9. Acknowledgments
|
||
|
||
These are the orignal acknowledgments documented by Michael De La Rue. They
|
||
have been included in their entirety to ensure that each persons efforts to
|
||
make Linux more accessibile are acknowledged.
|
||
|
||
Much of this document was created from various information sources on the
|
||
Internet, many found from Yahoo and DEC's Alta Vista Search engine. Included
|
||
in this was the documentation of most of the software packages mentioned in
|
||
the text. Some information was also gleaned from the Royal National Institute
|
||
for the Blind's help sheets.
|
||
|
||
T.V. Raman, the author of Emacspeak has reliably contributed comments,
|
||
information and text as well as putting me in touch with other people who he
|
||
knew on the Internet.
|
||
|
||
Kenneth Albanowski [mailto:kjahds@kjahds.com] kjahds@kjahds.com provided the
|
||
patch needed for the Brailloterm and information about it.
|
||
|
||
Roland Dyroff of [http://www.suse.de/] S.u.S.E. GmbH (Linux distributors and
|
||
makers of S.u.S.E. Linux (English/German)) looked up KTS Stolper GmbH at my
|
||
request and got some hardware details and information on the Brailloterm.
|
||
|
||
The most major and careful checks over of this document were done by James
|
||
Bowden, [mailto:jrbowden@bcs.org.uk] jrbowden@bcs.org and Nikhil Nair
|
||
[mailto:nn201@cus.cam.ac.uk] nn201@cus.cam.ac.uk, the BRLTTY authors who
|
||
suggested a large number of corrections as well as extra information for some
|
||
topics.
|
||
|
||
The contributors to the blinux and linux-access mailing lists have
|
||
contributed to this document by providng information for me to read.
|
||
|
||
Mark E. Novak of the Trace R and D centre [http://trace.wisc.edu/] http://
|
||
trace.wisc.edu/ pointed me in the direction of several packages of software
|
||
and information which I had not seen before. He also made some comments on
|
||
the structure of the document which I have partially taken into account and
|
||
should probably do more about.
|
||
|
||
Other contributors include Nicolas Pitrie and Stephane Doyon.
|
||
|
||
A number of other people have contributed comments and information. Specific
|
||
contributions are acknowledged within the document.
|
||
|
||
This version was specifically produced for [http://www.redhat.com/]
|
||
RedHat's Dr. Linux book. This is because they provided warning of it's
|
||
impending release to myself and other LDP authors. Their doing this is
|
||
strongly appreciated since wrong or old information sits around much longer
|
||
in a book than on the Internet.
|
||
|
||
No doubt you made a contribution and I haven't mentioned it. Don't worry, it
|
||
was an accident. I'm sorry. Just tell me and I will add you to the next
|
||
version.
|