GSoC'14 Project Summary

September 2nd, 2014

Like all good things, GSoC’14 had to come to an end. Thanks to my mentors, Shantanu and Peter, I was able to complete all the things I promised in my proposal. In this post I will try to summarize my whole work during the GSoC.

My project was to “Integrate Plasma Media Center with Simon”. The goal was to allow a user to control PMC through voice commands (using Simon). This required PMC to expose a D-Bus interface through which other programs (including but not limited to Simon) could communicate with it. On the other end, Simon required a plug-in to be able to communicate with PMC.

The interface for PMC and the Simon plug-in, both were based on MPRIS specifications which allows them to communicate with other applications based on those specs. For example: any MPRIS based controller like “Now Playing” plasmoid can control PMC. Similarly, the Simon plug-in can be used to control other MPRIS compatible media players like VLC, Dragon, Amarok etc.

Following was my course of action to complete the project:

  1. Added Root and Player MPRIS interfaces to PMC. This made PMC MPRIS compatible. Below is a snapshot of the “Now Playing” plasmoid and the taskbar preview exploiting the D-Bus interfaces of PMC.

  2. Created a command plug-in for Simon based on MPRIS specs. It allowed a user to control any MPRIS compatible media player through voice commands. It could control the playback of media and change volume. This plug-in was to be improved later so that a user can play a song in his playlist by saying its name.

  3. Added Tracklist MPRIS interface to PMC. This allowed other applications to keep track of PMC’s playlist and play a particular song from it. The Simon plug-in was to interact with this interface to let a user play a song from the current playlist just by saying its name.

  4. Improved the plug-in mentioned in (2) so that a user can play a song by saying its name. This works in the following manner:
    • Simon plug-in keeps track of MPRIS compatible media players registered on D-Bus
    • It maintains a list of tracks in a media player by listening for signals of Tracklist interface
    • For each track a new command is created (or deleted when the track is removed) with the track’s title as trigger (as shown in the snapshot)
    • When a user says the name of a track, a command with that name is triggered and a GoTo method call is used to play that particular song
  5. Created a Simon scenario based on English HUB4 SPHINX model using the plug-in mentioned in (4) so that the user need not setup the commands manually. Download the scenario, import it in Simon and you can control your favourite MPRIS media player (read PMC ;) ).

Now that the project is complete, I request you to test it and please report bugs. You can ping me on IRC for any help. My IRC nickname is madeti and you can find me in channels #plasma or #kde-speech.