ThinClientAudioSupport

Revision 2 as of 2005-10-31 21:44:21

Clear message

Summary

Thin Client Audio Support how to get audio to the thin clients

Rationale

Since LTSP sessions currently run fully on the server and there is no tweakage done, the first LTSP Client grabs the avilable audio device to play sounds. For dapper the sound output needs to get redirected to the Thin Client over the network to use the actual sound device the user listens to Smile :)

Use cases

Ian clicks on a menu item in gnome and the "plop" sound used for the menu item get put out on the servers soundcard...

Daniel is playing a movie and since he is sitting on the Thin Client that logged in as the second client, there is no sound output for him at all.

Wilma has edited some wav files in the music class at her schoool where a edubuntu LTSP server is used, but she cant play back the edited sound files because there is no sound suppot for the Thin Clients in edubuntu LTSP yet.

Scope

Options:

  • ALSA itself does not support network operation
  • esound sucks
  • polypaudio is dead upstream
  • jack
  • gstreamer: too limited scope
  • nas: poor performance
  • mas: dead upstream
  • vsound: only supports OSS

Design

Idea (network sound for the poor): Have ALSA output to a file/pipeline, and forward this (netcat/ssh) to the client. We should evaluate whether this works in principle (if this works we should make it the default for dapper+1 !).

For dapper, ltsp should still default to esound but forward the sound through a ssh tunnel to no break the current secure model we use with the ew ltsp implementation. We can automatically detect this in the planned automatic backend for gstreamer.

Implementation

Code

Data preservation and migration

Outstanding issues

BoF agenda and discussion