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Linux

What is Linux?
Linux and Accessibility
Which versions of Linux do most people use?
Which version provides the best access?
Linux/ Ubuntu Access Features
External links

What is Linux?

Every desktop computer, laptop or mobile phone uses an operating system. The most popular operating systems in use today are:

Windows
Mac OS
Linux

Linux is one of the most prominent examples of free and open source software collaboration. Linux software is particularly popular amongst users of the recently launched netbooks. Most Linux distributions include a graphical user interface.

Since 1993, a lot of people and organisations have been distributing Linux operating systems. Reports suggests that are over 350 active distributions.

Linux and Accessibility

For several years, a number of accessibility-related tools have existed for Linux. Until recently, graphical desktops on Linux, which behave similarly to those on Windows or Mac, have remained inaccessible to users with various disabilities.

Recent significant improvements have occurred through the GNOME Accessibility Project, which focuses on the accessibility of a very popular Linux desktop called GNOME. The project has worked to build improved accessibility features into GNOME and to create a screen reader, braille output software, and a sophisticated on-screen keyboard.

Which versions of Linux do most people use?

Some distributions are more popular than others. The most famous and popular are listed at the Linux Forums. They include:

Debian

Debian is one of the oldest Linux distributions. It was created in 1993 by Ian Murdock. The Debian project is non-commercial and gathers more than a thousand developers throughout the world.

Pros: Non-commercial, strong community, stable and fast.
Cons: Infrequent releases, limited hardware detection.

More information about Debian can be found at the Debian website.

Fedora

One of the best known Linux company in the world is Red Hat. In 2003, Red Hat decided to focus on business and stopped releasing its public distribution. Red Hat Linux 9 was the last version in the Red Hat product line and was replaced by Fedora Core.

Pros: Widely used, good support, innovative.
Cons: Not as stable as Debian, not as easy and up-to-date as Suse.

More information about Fedora can be found at the Fedora website.

openSuse

openSuse has always been seen as a distribution of choice for desktop installations. It benefits from a powerful installer and configuration tool.

Pros: Up-to-date, easy to use, stable.
Cons: Speed and performance.

More information about openSUSE can be found at the openSUSE website.

Ubuntu

In 2004 a distribution which was never heard of before, quickly became the most popular and famous of all distribution. Ubuntu features a fast release cycle, up-to-date and numerous packages, fast download mirrors, great documentation and shipment of CDs.

Pros: Great community of users and developers, great documentation, up-to-date packages.

More information about Ubuntu can be found at the Ubuntu website.

Which version provides the best access?

There is no definitive Linux distribution that is best for accessibility as they are are reliant on either the KDE or GNOME environment. However Ubuntu is widely cited for regular upgrades that include the latest translations and accessibility features that the free software community has to offer.

Ubuntu has been selected by readers of desktoplinux.com as the most popular Linux distribution for desktop, claiming approximately 30% of Linux desktop installations in both 2006 and 2007.

Ubuntu is an African word meaning 'Humanity to others', or 'I am what I am because of who we all are'.

Ubuntu comes installed with a wide range of software that includes OpenOffice (word processing, spreadsheet, database, and presentation software), email and calendering, tabbed web browsing, photo editing and a music player.

Ubuntu Netbook Remix is optimised to run on a new category of affordable Internet-centric devices called netbooks. It includes a new consumer-friendly interface that allows users to quickly and easily get on-line and use their favourite applications.

Linux Access Features

The default desktop environment for Ubuntu is GNOME, a leading UNIX and Linux desktop suite and development platform. Instructions presented here reference the Ubuntu environment, but can be applied across all Linux installations that have adopted the GNOME desktop.

High contrast

Ubuntu ships with a selection of high-contrast themes, complete with custom icons and mouse cursors.

To activate a new theme, go to the System menu, followed by Preferences -> Theme.

Prefence screen in Ubuntu

Magnification and speech synthesis

Orca is a screen reader and magnifier that enables users with limited vision, or no vision, to use the Gnome desktop and associated applications. The magnifier features automated focus tracking and full-screen magnification. The screen reader enables low-vision and blind users to access applications via speech and braille output. Key-mapped functions are organised on layers giving control over navigation, mouse, magnifier, speech and Braille devices. Orca can be customised to individual applications. This can make otherwise difficult interfaces, such as those of instant messaging clients, easy to use.

Orca is available on the Ubuntu Desktop CD.

Keyboard modifiers

The Gnome desktop environment supports several options for modifying the behaviour of the mouse and keyboard. The modifier keys (Shift, Ctrl and Alt) can be made Sticky so that when they are pressed once, they remain active until the next key is pressed. This enables users to write upper case characters or use keyboard shortcuts while only pressing one key at a time.

Other features include Slow Keys and Bounce Keys which control the reaction rate and repeat rate of keys and Mouse Keys which allow the numeric keypad to be used to control the mouse cursor. These features can be activated on the Keyboard Accessibility panel (from System -> Preferences -> Keyboard).

On-screen keyboard

Ubuntu 6.10 includes the onBoard on-screen keyboard, a lightweight text-entry application, extensible through macros, scripts and custom layouts.

Also available is Gnome On-screen Keyboard (GOK), which in addition to basic text entry, also provides facilities for controlling the entire desktop behaviour through the on-screen keyboard by gathering information about other applications and sending them control signals through the Gnome assistive technology framework AT-SPI.

The onscreen keyboard in Ubuntu

Dasher

Dasher is a tool which enables users to write without using a keyboard. Text is entered by using a pointing device such as a mouse, a touchpad, a touch screen, a roller ball, a joystick, a Wii Remote, or even mouses operated by the foot or head.

Dasher is a zooming interface. You point where you want to go, and the display zooms in wherever you point. The world into which you are zooming is painted with letters, so that any point you zoom in on corresponds to a piece of text. The more you zoom in, the longer the piece of text you have written. You choose what you write by choosing where to zoom.

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Dasher is available for download and is compatible with several platforms including Mac OS, Microsoft Windows, Pocket PC, and Unix-like operating systems with GTK support.

Getting started

The Desktop CD

The easiest way to try out the Ubuntu accessibility tools is with the standard Ubuntu Desktop CD, which can be started directly with a range of tools already installed and running. The CD can be downloaded from at the Ubuntu website (select the 'desktop' version for your architecture).

Assistive Technology Preferences in Ubuntu

Activating pre-installed tools

If you install the Ubuntu system after booting the Ubuntu Desktop CD with an accessibility option as described above, those features will also be pre-configured to start by default on your newly installed system.

The most common accessibility tools such as Orca and onBoard are pre-installed on any standard Ubuntu system and are easy to activate. The screen reader, magnifier and on-screen keyboard are all activated using the Gnome Assistive Technology Preferences panel found in the System menu under Preferences.

External Links

How to get Ubuntu

You can download Ubuntu at the Ubuntu website or get Ubuntu CDs or DVDs shipped to you. You can also make a request for a free CD.

Help and documentation

Some Ubuntu accessibility documentation exists, including a getting started guide. You can also join the ubuntu forum!

The BBC website maintains a comprehensive resource of the many ways you can make your Linux computer, keyboard, and mouse better suit your needs

Other Resources

The Linux Foundation Accessibility Workgroup
Debian Accessibility Project
a11y projects for desktop environments:

a11y projects for software:

BLINUX - Project who's aim is to improve the usability of the GNU/Linux operating system for users who are blind.
Orca screen reader

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Additional Information

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HTML5 media player accessibility: the potential and the reality

In last month's W3C update I outlined some of the benefits of HTML5 that the W3C believes will have a significant impact on how people will use the web. As multitouch, tablet and portable multimedia devices become more popular the promise of drag-and-drop functionality and standardised video could have a great impact on our productivity and entertainment needs.

In terms of accessibility, there are two key areas that HTML5 has the potential to deliver: the ability for people with disabilities to use its new features, and effective communication between assistive technology and the web browser. This month we’ll look at the first one, and discuss the evolution of browser-AT interaction, WAI-ARIA, in forthcoming reports.

Accessible media players

One of the biggest issues for people with disabilities in implementations of current web browsing is video integration. For people who are hearing impaired, this means the availability of standardised caption techniques. For people with vision and mobility impairments, the biggest issue is keyboard navigation to actually play and control the video. With so many video formats and integrated players, simply playing a video can be an uphill battle.

While the new video standard offers great promise of improving and standardising captions, the W3C believes the huge step forward for web accessibility is the accessible embedded media player.

How does it work?

Currently websites like YouTube are difficult to use for people with vision and mobility impairments because the buttons in the video player, such as ‘play’ and ‘stop’, can’t be selected with the keyboard alone. Although solutions have been developed, they are non-standard, difficult to find, and it’s unlikely that the website a person with a disability wants to use will have an accessible player feature.

HTML5 basically provides new commands such as <video> and <audio> which can create and label the buttons in a way that allows keyboard shortcuts to access them, and screen readers to tell the user which buttons are available. This means a person who has a vision or mobility impairment can easily use the keyboard to start, stop and navigate around a video, and people who are vision impaired using a screen reader will also have words such as ‘stop’ and ‘play’ read out to them when the keyboard focus is on the buttons.

Can an HTML5 accessible media player be put on my website now?

Given that many web browsers support HTML5 to some degree, the answer is both yes and no. It can be done, but because HTML5 is still an evolving standard and both browsers and assistive technology products handle HTML5 commands in different ways, it’s hard to create an accessible media player that will work for everyone.

Having said that, there is an excellent guide published by Terril Thompson that provides many tweaks and hacks that can get a customised HTML5 accessible media player up and running.

How are the browsers and screen readers going with HTML5?

In terms of the web browser implementation of HTML5, Opera is leading the way and has enough functionality to support a standard accessible media player. Firefox 3.6 and Safari both work to some degree but still need some development, while Internet Explorer 8 and Google Chrome do not currently provide any support for HTML5 keyboard or AT accessibility. Microsoft has indicated, however, that more work will be done on this for the release of Internet Explorer 9.

As for screen readers, the best result for Windows users is to use NVDA with Firefox, and Mac users should consider the built-in tools of VoiceOver with Safari. JAWS for Windows currently doesn’t support many of the HTML5 commands.

Where to for HTML5?

The release of the HTML5 standard is currently one of the W3C’s highest priorities, and all the browser development organisations of Microsoft, Apple, Mozilla, Opera and Google are heavily involved in the W3C. Although it will still be many months, possibly years until the standard is officially completed, the browsers will continue to evolve and accessibility will continue to improve.

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