Why Video calls on a mobile device don't just work.

Session information has not yet been published for this event.


One Line Summary

An overview of what is involved in making video calls and the issues typically encountered on mobile platforms.


Video calling is a challenging undertaking in the best of times. It combines most multimedia-usecase., in a video call the application is simulationously capturing, encoding, sending, receiving, decoding and displaying audio and video. Essentially it’s doing the tasks of a video recording application, a video player and a streaming server all at the same time.
Doing this on a resource-contrained mobile platform adds even more challenges, especially when HD video is thrown into the mix.

I will give a brief overview of how VoIP works and how Telepathy, Farsight and Gstreamer are used to implement it.

Afterwards i will go through the various issues that are commonly seen when implementing this on a mobile platform. This includes issue with resource allocation (e.g. availability of camera devices, accelerated video outputs), the usage of hardware codecs, issues when wireless power management gets in the way, etc.

While this talk itself doesn’t provide any concrete solutions, it should give a good overview of what kind of demands are placed on the lower level system by applications like VoIP and what pieces of infrastructure are still missing on linux systems.


gstreamer, telepathy, mobile, Voip, Farsight

Presentation Materials



  • Sjoerd Simons

    Collabora Ltd


    Sjoerd is a Software Engineer at Collabora. He works on various things, both during work ours and in his spare time, these mostly involve Telepathy, Farsight, Gstreamer, Empathy and Debian