KTp/Components/Call UI

The plan

• The current code is wrong by design, needs to be replaced.

• Build a simple Qt library that exports the whole call application logic with a QML-izable interface, using QtGStreamer/farsight/farsight utils/telepathy-qt4.

• Build a GUI that possibly consists of a standard KXmlGuiWindow that embeds a QDeclarativeView, which implements the call GUI.

Blockers

• Needs telepathy-qt4 to export interfaces for the Call spec.
  • tp-qt4-yell exports them now. will soon be merged to tp-qt4.
• Needs a QML video widget in QtGStreamer.
  • this is work in progress.
  • we need it if and only if we build the interface using QML.

GUI Ideas

• Alvaro's mockup

• empathy's new call UI mockup

Dependency hell

• telepathy-qt:
  • Provides Qt high level api to telepathy.
  • http://cgit.freedesktop.org/telepathy/telepathy-qt4/

• telepathy-qt-yell:
  • Provides Qt high level api for the Call interface (will be merged to tp-qt at some point)
  • http://cgit.freedesktop.org/telepathy/telepathy-qt4-yell/

• qt-gstreamer:
  • Provides Qt bindings for GStreamer
  • http://cgit.freedesktop.org/gstreamer/qt-gstreamer

• farsight2 (soon to be farstream):
  • This is the library and gstreamer elements that do the actual media streaming.
  • http://cgit.collabora.com/git/farsight2.git/

• telepathy-farstream:
  • Provides the glue between telepathy CMs and farsight2/farstream.
  • http://cgit.freedesktop.org/telepathy/telepathy-farstream/
  • (Note: use the telepathy-farstream-0.1 branch with farsight2 / master is to be used with farstream)

How it all blends together

telepathy-qt-yell provides the Tpy::CallChannel class, which wraps the Channel.Type.Call d-bus object. From this object, we create a TfChannel (provided by tp-farstream) and we wrap it in a QTf::Channel object (provided by libqtf inside the call-ui repository; this is qt-gstreamer based bindings for tp-farstream). This TfChannel object does all the internal communication with the CM and constructs some GStreamer bin (using farsight2/farstream internally) that will do all the streaming. On this bin, we connect our GStreamer sources and sinks using the QtGStreamer API.