Emacspeak: The Complete Audio Desktop Under Pulseaudio
1. Executive Summary
Porting Emacspeak sound environment to Pulseaudio.
Until now, emacspeak features that enhance the auditory display have relied exclusively on ALSA and avoided Pulseaudio all together. As Pulseaudio improves, and simultaneously gets harder to get rid of, I recently ported the required features to work under Pulseaudio, see below for details.
2. Summary Of Auditory Display Enhancements
- Notifications, e.g., speaking the time, incoming IM messages
etc. are spoken on a separate notification stream.
- The above normally plays on the right ear, but enhanced with a binaural effect.
- This can be configured to be on the left ear when running Emacspeak remotely on a cloud-top.
- A Bauer Stereo To Binaural (BS2B) filter is applied to all output streams to provide an enhanced headphones listening experience.
- The outloud server has been updated to request lower latency from Pulse; Pulseaudio defaults are too high for highly responsive TTS.
For details on Emacspeak's enhancement to the auditory display, see prior articles listed in the References section.
3. Configuring Pulseaudio To Enhance The Auditory Display
All of these features have been available until now by installing a
custom .asoundrc; these are now available under Pulseaudio by
installing a .config/pulse/default.pa in the user's home directory.
cp EMACSPEAK_DIR/etc/pulse/default.pa ~/.config/pulse; pulseaudio -k
The above is a one-time operation that sets up the audio environment — see etc/pulse/README.org.
4. References
- Augmented Headphone Listening On Linux For The Emacspeak Audio Desktop
- Soundscapes On The Emacspeak Audio Desktop
- Follow-Up: Soundscapes on the emacspeak Audio Desktop
- A Ladspa Work-Bench For The Emacspeak Desktop
- Generating Spatialized Auditory Icons Using MPlayer And Ladspa
- Listening To Multiple Media Streams On The Emacspeak Audio Desktop
- Using Multiple TTS Streams On The emacspeak Audio Desktop
- Enhanced Audio On The Emacspeak Desktop
