On ChromeOS, you can enable spoken feedback (ChromeVox) by pressing Ctrl+Alt+Z.
If you have a Chromebook, this gives you speech support built-in. If you‘re building Chrome from source and running it on desktop Linux, speech and braille won’t be included by default. Here's how to enable it.
First follow the public instructions for Chrome checkout and build.
Edit .gclient (in chromium/) and at the bottom add:
target_os = ["chromeos"]
Run gclient sync to update your checkout.
Then create a GN configuration with “chromeos” as the target OS, for example:
gn args out/cros
...in editor, add this line:
target_os = "chromeos" is_component_build = true is_debug = false
Note: Only target_os = "chromeos" is required, the others are recommended for a good experience but you can configure Chrome however you like otherwise. Note that Native Client is required, so do not put enable_nacl = false in your file anywhere!
Now build Chrome as usual, e.g.:
autoninja -C out/cros chrome
And run it as usual to see a mostly-complete ChromeOS desktop inside of a window:
out/cros/chrome
By default you'll be logged in as the default user. If you want to simulate the login manager too, run it like this:
out/cros/chrome --login-manager
You can run any of the above under it’s own X session (avoiding any window manager key combo conflicts) by doing something like
startx out/cros/chrome
ChromeVox expects that the Search key is mapped from your left Windows key/LWIN/key code 91; however, your window manager/desktop environment (Linux) treats this as a Super or Meta which usually gets assigned to numerous shortcut combinations.
To avoid these conflicts, run using startx as described above.
If you decide not to run under X or wish to run Linux within a window manager such as through Chrome Remote Desktop or a virtual machine, you need to remap keys either in Linux or inside ChromeOS.
To manually disable all conflicting key combinations in Linux, remove all keyboard bindings that reference “Super” or “Meta” in System Settings > Keyboard > Shortcuts.
To remap the Search key inside ChromeOS, go to Settings > Device > Keyboard. The control key is a good choice for setting as Search as there should be no conflicts with Linux on its own. Caps Lock is not recommended to change as ChromeVox may handle it as a special case.
If you want speech, you just need to copy the speech synthesis data files to /usr/share like it would be on a ChromeOS device:
gsutil ls gs://chromeos-localmirror/distfiles/espeak\*
Pick the latest version and
VERSION=1.51 TMPDIR=$(mktemp -d) gsutil cp gs://chromeos-localmirror/distfiles/espeak-ng-$VERSION.tar.xz $TMPDIR tar -C $TMPDIR -xvf $TMPDIR/espeak-ng-$VERSION.tar.xz sudo mkdir -p /usr/share/chromeos-assets/speech_synthesis/espeak-ng/ sudo chown -R $(whoami) /usr/share/chromeos-assets/ cp -r $TMPDIR/espeak-ng/chrome-extension/* /usr/share/chromeos-assets/speech_synthesis/espeak-ng rm -rf $TMPDIR
Be sure to check permissions of /usr/share/chromeos-assets, some users report they need to chmod or chown too, it really depends on your system.
Note that the default Google tts engine is now only available on an actual ChromeOS device.
After you do that, just run “chrome” as above (e.g. out/cros/chrome) and press Ctrl+Alt+Z, and you should hear it speak! If not, check the logs.
ChromeVox uses extension APIs to deliver braille to Brltty through libbrlapi and uses Liblouis to perform translation and backtranslation.
Once built, Chrome and ChromeVox will use your machine’s running Brltty daemon to display braille if ChromeVox is running. Simply ensure you have a display connected before running Chrome and that Brltty is running.
Note you may need to customize brltty.conf (typically found in /etc). In particular, the api-parameters Auth param may exclude the current user. You can turn this off by doing: api-parameters Auth=none
Testing against the latest releases of Brltty (e.g. 6.3 at time of writing) is encouraged.
For more general information, see ChromeVox
ChromeVox keyboard shortcuts use Search. On Linux that‘s usually your Windows key. If some shortcuts don’t work, you may need to remove Gnome keyboard shortcut bindings, or use “startx”, as suggested above, or remap it.