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orca

NAME

orca - a screen reader / magnifier

SYNOPSIS

orca [-s] [--gui-setup] [--setup] [-t] [--text-setup] [-n] [--no-setup] [-u dirname] [--user-prefs-dir=dirname] [-e [speech|braille|braille-monitor|magnifier|main-window]] [--enable=[speech|braille|braille-monitor|magnifier|main-window]] [-d [speech|braille|braille-monitor|magnifier|main-window]] [--disable=[speech|braille|braille-monitor|magnifier|main-window]] [-?] [--h] [--help] [-v] [--version] [-q] [--quit]

Orca is a screen reader for people with visual impairments, and provides alternative access to the desktop by making use of speech synthesis, braille, and magnification support on the platform.

In addition, orca only provides access to applications/toolkits that support the assistive technology service provide interface (AT-SPI), which include GTK, Mozilla, Firefox, Evolution, OpenOffice, StarOffice, Java/Swing, etc.

The following options are supported:

-s When starting orca bring up the GUI configuration dialog. You can also use --gui-setup or --setup to specify this option.

-t When starting orca initiate the text-based configuration. You can also use --text-setup to specify this option.

-n When starting orca force the application to be started without configuration, even though it might have needed it. This is useful when starting orca via something like gdm. You can also use --no-setup to specify this option.

-u When starting orca, use dirname as an alternate directory for the user preferences. You can also use --user-prefs-dir to specify this option.

-e When starting orca, force the enabling of the supplied options. You can also use --enable to specify this option.

-d When starting orca, force the disabling of the supplied options. You can also use --disable to specify this option.

-? Show the help message of this release of the orca program. You can also use -h or --help to specify this option.

-v Return the orca version number. You can also use --version to specify this option.

-q Quit orca. You can also use --quit to specify this option.

In order for this "Accessible GNOME Desktop" to be accessible to users who are blind or have low vision, users will need to employ an assistive technology (AT) that exposes the graphical desktop information encoded in the GNOME Accessibility Framework.

Customers with blind employees/students need to have the ability to adapt and customize their assistive technology solutions - both to improve the efficiency of their blind users (to help make up for disadvantages inherent in not being able to "see" the entire screen immediately at a glace), and also to "work around" poorly designed and not particularly accessible applications that their blind users need to use.

orca is an extensible assistive technology that provides end-user access to applications and toolkits that support the GNOME Accessibility Framework. It has been designed with direct continual feedback from its disability user community.

orca uses a "scripting" approach to easily allow customization per application and provides the ability for each user to further customize their AT environment based on their own preferences. The "scripting" approach of orca provides a much more adaptable and compelling assistive technology solution than existing AT for the JDS desktop.

Functionally orca has to do 4 major things:

1. Present information to the user via speech synthesis (text-to-speech), or refreshable braille (hardware connected to serial or USB port), or a magnified image on the user's display.

2. Acquire information from the applications and desktop graphical display via the GNOME Accessibility Framework.

3. Track events occurring in the applications and desktop graphical display via the GNOME Accessibility Framework.

4. Intercept and optionally consume user input events from the system keyboard and the buttons on a refreshable braille display. Based on the input, orca will either pass the event on to the application for normal processing, execute Orca-specific commands (such as reading the next line in the display or panning the braille display), or perform operations on application objects (such as clicking buttons or modifying text areas).

orca will also:

* be a collection of building blocks that comprise screen reading and magnification technology, including use of text-to-speech, braille input/output, magnification logic, screen reading logic, keyboard and mouse interception modules, and event coalescing.

* be developed with the standard GNOME build environment.

* support multiple braille displays.

* support the gnome-speech module for text-to-speech.

* intercept keyboard & mouse events through the GNOME Accessibility Framework and other supported X mechanisms.

* support the gnome-mag module to provide end-user magnification of the screen between 2 and 16 times magnification in integer increments.

* render its own graphical user interface using GTK+ widgets.

* provide a scripting mechanism, giving it the ability to customize how each application on the JDS desktop is handled by orca.

* provide further customization on a per-user basis.

Orca provides a set of its own keyboard commands. Note that you can always enter Orca's "learn mode" while running Orca by pressing Insert+F1. When in learn mode, Orca will intercept all keyboard and braille input events and will tell you what the effect of them would be. To exit learn mode, press the escape key.

* Commands for adjusting speech parameters

- Insert-right arrow

increase speech rate

- Insert-left arrow

decrease speech rate

- Insert-up arrow

raise the pitch

- Insert-down arrow

decrease the pitch

* Flat review commands

- Numpad-7 move the flat review cursor to the previous line, and read it.

- Numpad-8 read the current line.

- Numpad-9 move the flat review cursor to the next line, and read it.

- Numpad-4 move the flat review cursor to the previous word, and read it.

- Numpad-5 read the current word. Double tap on Numpad-5 to spell word, triple tap on Numpad-5 to get military spelling.

- Numpad-6 move the flat review cursor to the next word, and read it.

- Numpad-1 move the flat review cursor to the previous character, and read it.

- Numpad-2 read the current character.

- Numpad-3 move the flat review cursor to the next character, and read it.

- Numpad-slash perform a left mouse click at the location of the flat review cursor.

- Numpad-star perform a right mouse click at the location of the flat review cursor.

- Numpad-plus speaks the entire document.

- Numpad-Enter perform a "where am I" operation.

- Numpad-Delete bring up the Find dialog.

Note: the above commands apply when working with objects as well as when working with text. For example, if the flat review cursor were positioned on a menu bar, pressing the read current line command would speak the names of all visible menus. Similarly, pressing read next word would speak the object to the right of the flat review cursor on the same line, or move flat review to the next line if no more objects were found.

* Miscellaneous functions

- Insert-F1

enter learn mode (press escape to exit)

- Insert-f

speak font and attribute information for the current character.

- Insert-space

launch the Orca Configuration dialog.

- Insert-Control-space

reload user settings and reinitialize services as necessary.

- Insert-s

toggle speech on and off

- Insert-F11

toggle the reading of tables, either by single cell, or whole row.

-Insert-q

quit orca.

* Commands for debugging

- Insert-F3 report information on the currently active script.

- Insert-F4 cycle through Orca's various debug levels.

- Insert-F5 prints a debug listing of all known applications to the console where Orca is running.

- Insert-F7 prints debug information about the ancestry of the object with focus.

- Insert-F8 prints debug information about the application with focus.

Note, in order for the last three commands to be of use, Orca needs to be started from a virtual console or via gnome-terminal. Output is sent to the console only (i.e., it is not sent to speech or braille).

The following exit values are returned:

0 Application exited successfully

1 Application exited with error

2 orca cannot parse its command line options.

The following files are used by this application:

/usr/bin/orca orca executable

~/.orca/user-settings.py user's personal configuration settings for orca

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Availability	SUNWgnome-a11y-orca
Interface stability	External

orca online reference manual.

Latest version of the GNOME Accessibility Guide for your platform.

Latest version of the GNOME Desktop User Guide for your platform.5

Written by Rich Burridge, Sun Microsystems Inc., 2006-2007.