This article explains the screen reader Orca for graphical desktop environments such as GNOME, MATE and others. The official documentation is at https://help.gnome.org/users/orca/stable/ .
If you have enabled accessibility during the Debian installation and also installed a desktop system, accessibility is enabled by default and Orca was installed for you automatically. This only works for GNOME, Mate, Cinnamon and Unity at the moment, but can be activated manually. See the section on autostarting Orca.
Installation on an existing system
If you installed Debian without accessibility features, you should do the following steps:
In a terminal, type sudo apt install orca, to install orca.
- If you are using one of GNOME, Mate, Cinnamon or Unity, the next steps should not be required for you.
In a graphical session, open a terminal or press Alt+F2 and type orca -s to start the setup. If you are unable to do so, it is best to enable the autostart of Orca and run the setup with Orca support with the command orca -r -s.
- In the upcoming dialogs, you can select the options you like, including Orca modifier, etc. After this procedure, Orca should start automatically.
Orca does not offer magnification itself, however a variety of solutions exist, which are documented ?here
Orca has support for two rendering engines, Gecko and ?WebKit. The former is used within firefox and has the best support. The latter, Webkit, is used within various browsers. They work to a certain degree, but cannot be considered production-ready with Orca yet. You need to press F7 in those browsers to activate caret browsing.
Other speech synthesizers
Orca does not itself interact with the speech synthesizer, but uses a backend service called speech-dispatcher to access various speech synthesizers. If you want to customize or extend available synthesizers, please see the Speech-Dispatcher section.
The package orca-sops provides a plugin system together with a selection of default plugins. It also contains a guide to help getting started with plugin development.
Newer, experimental versions of Orca
If you don't want to compile Orca from source but still try a newer version (at your own risk), you can try using the version from unstable (or if available, from experimental). For this, you have to configure apt-pinning. Add a Debian unstable / experimental-source of Debian, update your package lists and run
sudo aptitude -t unstable install orca
WARNING: unstable and experimental don't have their names without reason!