Voluble - let your GNOME desktop speak to you.

Voluble is a simple GNOME shell extension that brings a natural-sounding, human-like voice to the desktop notifications used to alert the GNOME user of desktop events, appointments, e-mails, etc. Here is an example video:

voluble.mp4

Features:

• Read desktop notifications with human-like voice ( Piper).
• Mute / Unmute text to speech.
• Respect system "Do not Disturb" switch.
• Read mouse selection on command (ignores non-text selections).
• "About" triggers a demo notification (read outloud).

Voluble is not an accessibility tool, it does not aim to replace tools like Orca which expose functionality needed by users with disabilities. It simply enhances the desktop notifications by reading them outloud, in the absence of (or in addition to) any sound that might accompany the notification. This way, the user will be properly alerted and will not risk missing even the most transient of notifications, clearly hearing what the computer has to say, even when not looking. A reason for creating this extension has been the desire to hear the contents of notifications for appointments and to-do's from the Joplin note-taking app. A video demonstration.

NEW - a feature enhancement for users of Joplin. Have a summary of the tasks due in the next 12 hours read outloud at the start of a desktop session. Uses the optional python script joplintoday.py.

Notification - Tasks in the next 12 hrs	Notification Audio
	joplin-today.mp4

Once Voluble is installed (see Quick Start), you can simply invoke the python script by adding it to you startup applications. On most Linux desktops, placing a .desktop file in ~/.config/autostart/ will do the trick. Here is a sample ~/.config/autostart/joplintoday.desktop file:

[Desktop Entry]
Type=Application
Exec=/home/YourUsername/.local/bin/joplintoday.py
Hidden=false
NoDisplay=true
X-GNOME-Autostart-enabled=true
Name=JoplinToday

(Linux only, will likely not work with encrypted database).

Piper

Unlike the default installation of the afforementioned Orca (and speech-dispatcher in the background), Voluble uses a modern neural text-to-speech (TTS) engine called Piper. Among the multiple (and growing) choices of human-sounding neural TTS options, Piper is fast and lightweight for its decent quality (a quantum leap from the default espeak-ng in speech dispatcher). We can set up Voluble with Piper in two ways (not mutually exclusive):

• For a quick start, we can set up Voluble to use Piper directly, completely ignoring the infrastructure provided by speech dispatcher.
• If instead, we do not want to go rogue and prefer to play nice with the system logic, it is actually possible to use speech dispatcher to call Piper as a backend synthesizer to speak out-loud the notifications but we need to register Piper as a valid backend module first. The advantage with Piper set as the default speech synthesizer in speech dispatcher is that accessibility tools like Orca will then also sound nice. Just pressing Super + Alt +S will start Orca with Piper and we will hear clear human-like voice as we navigate the GNOME GUI.

Quick Start

• Download Piper from the GitHub releases page. It can be run with Python, but the binary releases are suggested here as they can give an edge of performance in this scenario.
• Download the desired voice files (a .onnx and a json file per each voice) for the language(s) of choice. As of this writing, 30 languages are supported. You can listen to samples and download files here. Once downloaded, make sure that each .json file is named exactly like its corresponding .onnx voice file.
• Make a symbolic link in your $PATH (say, in ~/.local/bin) to the piper executable:

 ln -s ~/FOLDER_WITH_EXTRACTED_PIPER/piper ~/.local/bin/piper

• Install the Voluble GNOME shell extension -- either with one click install from the GNOME extension website.

  -- or manually, by clonning the code from Github (most up-to-date code):

git clone https://github.com/QuantiusBenignus/voluble && cd voluble && \
unzip [email protected] -d $HOME/.local/share/gnome-shell/extensions/ && \
gnome-extensions enable [email protected]

• Download the helper script voluble for this extension (if not cloned already), place it in your $PATH and make it executable, for example:

cd ~/.local/bin && wget https://github.com/QuantiusBenignus/voluble/blob/main/voluble  && chmod +x voluble

That is it, now the extension should work by speaking out-loud in human-like voice all that the computer has to say via notifications.

---

Speech Dispatcher Integration

Optional Step (click to expand)

Speech Dispatcher is a core accessibility tool designed to facilitate speech synthesis for people with visual impairments. It acts as a bridge between client applications (programs that produce spoken text) and software speech synthesizers (programs that convert text into speech). Speech Dispatcher would typically come preinstalled in many Linux distributions with the espeak-ng TTS engine as the default. The result does not sound good at all when compared with the quality of the new neural TTS engines. Here is a comparison, justifying the integration of Piper with speech dispatcher:

With espeak-ng	With Piper
v-espeak.mp4	v-lessac.mp4

• Configuration files (speechd.conf) are located in /etc/speech-dispatcher/ for system-wide settings and ~/.config/speech-dispatcher/ for per-user preferences.

• The spd-conf tool allows one to modify configuration options interactively or create per-user speech dispatcher configuration.

• Integration with synthesizers (TTS engines) is done via module configuration, but unfortunatelly, the supplied preconfigured modules sound unnatural, robotic and not quite intelligible.

• It is possible, with some work, to configure Piper as a TTS module for Speech Dispatcher.

  1. First create a generic local (per user) speech-dispatcher setup with the spd-conf tool, using sd_generic as the default module.
  2. Then register Piper as a valid TTS module by editing the just-created ~/.config/speech-dispatcher/speechd.conf. Most stuff can be left as is (all is well commented). An excerpt of the relevant parameters in my case shown here:

   	# The Default language with which to speak
   	# Note that the spd-say client in particular always sets the language to its
   	# current locale language, so this particular client will never pick this configuration.
   	
   	DefaultLanguage   en-US
   	 
   	# Pulse audio is the default and recommended sound server. OSS and ALSA
   	# are only provided for compatibility with architectures that do not
   	# include Pulse Audio. 
  
   	AudioOutputMethod   alsa
  
   	# The next ones are instrumental, find them in their respective sections
   	
   	AddModule "piper"              "sd_generic"   "piper.conf"
   	DefaultModule piper
   	LanguageDefaultModule "en"  "piper"
   	LanguageDefaultModule "fr"  "piper"
  

  3. Then create a suitable piper.conf file in ~/.config/speech-dispatcher/modules/. Here is an example piper.conf adapted for my case from here:

   	Debug 0
   	GenericExecuteSynth "printf %s \'$DATA\' | piper --length_scale 1 --sentence_silence 0 --model ~/Store/Models/piper/$VOICE --output-raw | aplay -r 16000 -f S16_LE -t raw -"
   	# Using low quality voices to respect the 16000 rate for aplay in the command above is perfectly fine.
   	
   	GenericCmdDependency "piper"
   	GenericCmdDependency "aplay"
   	GenericCmdDependency "printf"
   	GenericSoundIconFolder "/usr/share/sounds/sound-icons/"
   	GenericPunctNone ""
   	GenericPunctSome "--punct=\"()<>[]{}\""
   	GenericPunctMost "--punct=\"()[]{};:\""
   	GenericPunctAll "--punct"
   	
   	#GenericStripPunctChars  ""
  
   	GenericLanguage  "en" "en_US" "utf-8"
   	GenericLanguage  "en" "en_GB" "utf-8"
   	GenericLanguage  "fr" "fr_FR" "utf-8"
   	
   	AddVoice        "en"    "MALE1"         "en_US-lessac-low.onnx"
   	AddVoice        "en"    "FEMALE1"       "en_US-amy-low.onnx"
   	AddVoice        "fr"    "MALE1"         "fr_FR-gilles-low.onnx"
   	AddVoice        "en"    "MALE2"         "en_GB-alan-low.onnx"
   	
   	DefaultVoice    "en_US-lessac-low.onnx"
  

  4. The newly created setup can then be tested with spd-say, for example:

     $ spd-say "Your computer can now speak to you nicely"

• Now all you have to do is set the option use_spd=1 in the CONFIG block of the voluble helper script to use speech-dispatcher instead of calling piper directly.

---

Tips & Tricks

The Mute function will keep notifications silent but is made by design to not affect the "Read Selection" button - selected text will be read nontheless. Since we have not implemented an "Interupt TTS" GUI action, if we goof up and select so much text that having it read out-loud for minutes fills us with regret, our salvation (or is it punishment) is to use the following command in the terminal or in the run window (ALT+F2):

pkill --signal SIGINT "[a]play"

(provided that we did not modify the voluble script to use something other than play or aplay). We should be careful to not omit the quotes or we may unintentionally kill a process named display for example. If we find yourselves too often a subject to this punitive action, creating an alias oops='pkill --signal SIGINT "[a]play"' in .bashrc (.zshrc, etc.) will help.

To-Do

• Add automatic translation for the extension GUI
• Make aware of system-wide "Do not Disturb"
• Add extension code for ver. 45+ of the GNOME shell

Credits

• Michael Hansen for making Piper a low-resource, good-quality speech synthesizer.
• The maintainers of the GNOME project.