Ubuntu aims at making the operating system, and its derivatives, usable by as many people as possible across ages, languages and physical abilities. This includes providing an accessible platform with high quality assistive tools, and ensuring that other applications work well with these. The assistive tools on Ubuntu, along with the entire operating system, are provided free of charge.

Visual Impairments

Screen Reader

  • Orca is screen reading software suitable for vision impaired and blind users.

Orca is a free, open source, flexible, extensible, and powerful assistive technology for people with visual impairments. Using various combinations of speech synthesis and Braille, Orca helps provide access to applications and toolkits that support the assistive technology service provider interface (AT-SPI), e.g. the GNOME desktop and Unity. The development of Orca has been led by Joanmarie Diggs at Igalia, with contributions from many community members.

The following information is for Ubuntu 14.04 and later.

Enabling the screen reader

The Orca screen reader can be enabled at any time when logged into a Unity or GNOME desktop session on any Ubuntu installation. The Orca screen reader will then be loaded every time you log into your session. Orca can be enabled and disabled using the Alt + Super + S keyboard shortcut. Orca can also be enabled and disabled using the same shortcut key at the login screen. The super key is also known as the Windows key.

It is also possible to enable Orca at install time, to help you independantly install Ubuntu onto your system. When you boot the live CD, you should hear a bongo drum sound. At this point, you can go ahead and enable Orca. Once again, the keyboard shortcut Alt + Super + S is used to enable orca. Orca should start speaking, and from this point you can select your language, and either boot into a live Ubuntu desktop by selecting the "Try Ubuntu" push button, or you can elect to install Ubuntu by selecting the "Install Ubuntu" push button.

If you enable Orca at install time, and install Ubuntu onto your system, some settings tweaks to improve application and desktop environment accessibility also get applied to both the live session if you are using it, and your newly installed Ubuntu system. These settings tweaks are not currently applied if you enable Orca after Ubuntu has been installed, however this may change in the future.

Orca basics

Orca is controlled with keyboard shortcuts that allow you to read part or all of the currently focused application window. There is 2 keyboard shortcuts for the vast majority of commands, one for use on a desktop keyboard, and the other for use on a laptop keyboard. Orca is set up to use the desktop keyboard layout by default, but can be configured to use the laptop keyboard shortcuts in its preferences. To access Orca preferences after enabling Orca for the first time, press insert + spacebar. A new window will open, and orca will announce "Screen reader preferences. General page tab." You can now configure Orca to your liking. If you switch the Orca keyboard layout to laptop, you use the caps lock key to perform Orca commands.

To access Orca's documentation, press Insert + H if you are using the desktop keyboard layout, and Capslock + H if you are using the laptop keyboard layout. Orca will speak its version, and give you pointers on how to learn how to use Orca and access its documentation. Pressing F1 will load Orca's documentation into the GNOME help viewer. Use the arrow keys to move through the documentation to read it. If you hear nothing, press the F7 key to enable caret browsing mode in the help viewer. This setting is already enabled if you install Ubuntu with Orca enabled at install time.

For further information on Orca, see the official Orca wiki page at http://live.gnome.org/Orca.

using orca with the Unity desktop

launching apps

Launching apps via the Unity Dash

The Unity desktop provides you with the ability to search your system for installed applications and files via the Dash interface. The dash can be opened using the keyboard in multiple ways. The quickest way is to press the Super key on your keyboard, otherwise known as the Windows key. You will then be placed in a search text field where you can start typing keywords to find the application you are looking for. Terms uch as "web browser" or "email" should help you find useful apps for browsing the web such as Firefox and Thunderbird.

Please note. As of Ubuntu 14.04, there are some accessibility issues with the dash where Orca cannot reliably read search results. Randomly using Orca's flat review functionality can sometimes make search results partially accessible, but this only seems to work once a session. Investigation is still ongoing as to the cause of this issue.

Launching an application from the Unity launcher

The Unity launcher is used to access regularly used applications, access files on removable media, and switch between running applications. The Unity launcher is accessible with the keyboard. To move to it, press Alt + F1 on your keyboard. You should hear Orca announce the first item on the launcher, which is "Search your computer and online sources". Using the arrow keys, you can move through the list of pinned applications, access any connected removable media, and access the Dash. The first icon that gets focus once you move to the launcher is another way you can get to the dash. Moving through the list of items on the Launcher, you will find some commonly useful applications and utilities. Files lets you access the contents of your home folder, Firefox is Ubuntu's default web browser, LibreOffice is the office suite shipped with Ubuntu, etc. To load an application, or open a file browser window for removable media, select the desired item with the arrow keys, and press enter.

Navigating the launcher can also tell you what applications you currently have open and running. For example, if you have Firefox open and you then navigate through the Launcher, when you navigate over the Firefox web browser item, you will be told that it is running. You should also hear the number of windows that are open for that application. Note that if an application is not running, you are given no information as to that applications' current state.

If you load an application and wish to keep it on the launcher, you need to pin it. This is done by navigating to the application on the launcher, pressing the right arrow key to open its context menu, otherwise known as a quicklist, and selecting the "Lock to Launcher" option. Other useful options are also provided by the quicklist, and the number of options available depends on the application in question.

switching between apps

There are 2 ways to switch between applications, via the Unity launcher as previously mentioned, and the application switcher. The application switcher is accessed by pressing and holding Alt, and pressing tab. Orca will announce that you are in the switcher window, and announce the currently selected application. If you only have one application open, then it will be selected. Otherwise, the next application in the list will be selected. TO move through the available options, keep holding the Alt key, and press tab. When you find what you are looking for, release the Alt key, and you will switch to the selected application. Note you can also go to the desktop from the application switcher. TO go to the desktop, look for "Show Desktop" in the switcher.

You can also switch between apps using the Unity launcher. To move to the launcher, press Alt + F1. Use the arrow keys to move through the available options on the launcher. Orca will notify you if the currently selected item is a running application, and if so, how many windows are open. TO switch to the selected application, press the enter key.

Most applications that are used in Ubuntu have a menu bar. The menu bar allows you to access many different functions of an application. There are 2 ways to get to the menus and menu items. If you know the shortcut for a particular menu in question, you can press and hold the Alt key, and then press the letter for the mnu in question. For example, if you want to access the file menu of an application, you would hold Alt, and press F. If you don't know what menus are available, and wish to browse the available menus and items, you can press Alt + F10 to get to the menu bar. You will be moved to the first menu in the menu bar. For most applications, this is likely File, or something similar. Use the down and up arrow keys to browse the currently opened menu, and use the left and right arrows to move between menus.

System indicators are used to display useful information to the user, such as current date and time, network connection status, sound, and much more. The system indicators share the same menu bar as application menus, so it is possible to navigate to them using the keyboard. As per above, you access the menu bar with Alt + F10, and navigate through the menus using the arrow keys. To navigate directly to the system indicators, press the left arrow key after pressing Alt + F10. This will move you to the system menu, which allows you to access system settings, shut down, restart, or lock your screen. Other indicators such as network, report your current network connection status, and allow you to connect to any available wireless network.

using orca with gnome

The below information is for GNOME shell, which is an alternative desktop environment to Unity. Both desktop environments share many pieces of infrastructure, such as the file manager, and have similar settings interfaces. As such, most of the information that applies to using Orca with Unity, in terms of navigating applications can also be applied to using GNOME shell.

installing gnome

There are multiple ways of installing GNOME shell. There is a GNOME derivative of Ubuntu that can be installed the same as Ubuntu with Unity, and you can also install GNOME shell on an existing Ubuntu installation. If you have Unity, and wish to install GNOME shell, you can search for GNOME shell in the Software Center. If you install via the software center, you will be asked about what display manager you wish to use. Both lightdm using the unity greeter and gdm are accessible, so feel free to choose the one you are most comfortable with. If you haven't used the GDM login manager before, select lightdm.

starting Gnome

When you log into your system, you can choose which desktop environment you wish to use. The following information is for logging in via the Unity login greeter, otherwise known as Unity greeter.

When you log in, you need to select your user name and enter your password should you have one. Before pressing enter to log in, press the tab key. Orca will announce that you are on the session push button. Press the spacebar to press this button, and open the list of available desktop environments.Use the tab key to cycle through the list to find out what options are available. You should see GNOME in the list. WHen you find the desktop environment you want, press space again, and tab back to the password field. You can then log in as normal.

launching apps

GNOME shell also has multiple ways to launch applications, the most prominant being searching for and activating apps from the search results. To search for and launch n application, press the Super key, aka the Windows key. Orca will announce "Window", although no more information is given. You can then start typing the app name or keywords to find he app you are looking for. As you type, Orca will announce the first result that appears. Once you have entered your search terms, you can then use the arrow keys to find what you are looking for.

To search through a list of available applications, press the super key, and then press and hold Control + Alt. Use the tab key to cycle through the available system windows until you find the dash option. Release Control and Alt. You are now in the list of pinned applications. Due to being more difficult to access via keyboard, this list of pinned apps is not as useful as it is in unity, so pinning applications will not be covered. At the bottom of the list, you will find the "Show Apps" option. Press enter, and then use the arrow keys to navigate all available applications.

switching between apps

The application switcher is accessed by pressing and holding Alt, and pressing tab. Orca will announce that you are in the switcher window, and announce the currently selected application. If you only have one application open, then it will be selected. Otherwise, the next application in the list will be selected. TO move through the available options, keep holding the Alt key, and press tab. When you find what you are looking for, release the Alt key, and you will switch to the selected application.

Like Unity, GNOME shell also has a top panel that lets you access some application menus, system settings and network configuration. To access the top panel, press and hold Control + Alt, and press the tab key until you hear Orca announce "Top Bar". Release Control and Alt, and use the arrow keys to navigate the items on the top panel. Press enter to open a menu, and use arrow to move through the available options. To return to an application, switch apps as per the documentation above.

High Contrast

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

To activate a new theme, press the super key on your keyboard and type "gnome-control-center" without the quotes. Press enter to activate the Gnome control center, and then click appearance.

Mobility Impairments

Keyboard Modifiers

The GNOME desktop environment supports several options for modifying the behavior 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, making it possible 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. In GNOME, these features can be activated on the Keyboard Accessibility panel (from the gnome control center, which can be accessed by pressing the super key on your keyboard, typing "gnome-control-center" without the quotes, and then pressing enter. In Xubuntu: Applications Menu -> Settings -> Settings Manager -> Accessibility -> Mouse tab -> check Use mouse emulation checkbox

On-screen Keyboard

Ubuntu 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 behavior through the on-screen keyboard by gathering information about other applications and sending them control signals through the GNOME assistive technology framework AT-SPI.

MouseTrap

MouseTrap makes computers accessible for people with physical impairments.

Mousetweaks

For users that cannot click with a hardware button, there is an utility named Mousetweaks that enables them to perform the various clicks by software.

Mousetweaks offers the following new features to the user:

  • Systemwide software click, usually called dwelling
  • Systemwide simulated right click through a click and hold of the left button (of course, for left-handed mouse users, the terms left and right have to be inverted)
  • An area on the panel to temporarily lock the pointer (provided by a panel applet) It uses image processing to translate the user's head movements into mouse events (movements and clicks) which allow users to interact with the different desktops managers and applications.

Dasher

Dasher provides an intuitive way to enter text without using the computer keyboard. It uses the head-mouse or eyetracker.

Voice Recognition

It is possible to control applications using voice commands. Julius speech recognition engine can be used to recognize voice commands and execute pre-set commands. Here is simple tutorial to get you started.

At the recent UDS 2009, a proposal for Voice Driven User Interfaces was discussed.

Also gnome-voice-control install and add to panel. For getting it better submit your voice to free GPL speech corpora http://voxforge.org Also theres voximp

http://en.wikipedia.org/wiki/Speech_recognition_in_Linux

Name

Using Voxforge

Preinstalled Commands

Customizable

Settings

Language support

gnome-voice-control

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voximp

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(X)

(X)

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Julius

(./)

Manually

(X)

(X)

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Simon Listens

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Cmu Sphinx

Activating preinstalled 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 preconfigured to start by default on your newly installed system.

The most common accessibility tools such as Orca and onBoard are preinstalled 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.

Using onboard and Mousetweaks at GDM

For users of Ubuntu 7.10 and above, it is possible to configure GDM so that onBoard and Mousetweaks are available during the GDM session.

This HowTo contains detailed explanations about how to configure GDM to make onBoard and Mousetweaks available and how to start them during the GDM session.

Resources

Accessibility (last edited 2015-06-01 22:45:32 by walterorlin)