Project MurX

The software that currently is (and in the future will be) made available here is the result of my research for my PHD thesis. The goal of the research was to implement a network-transparent multimedia system based on the X Window System. The code will be released in a piecemeal fashion as I am still busily removing embarassments.

A working prototype of the system was already presented at CeBIT exhibition 2007.

Why?

1. ssh into a remote box
2. fire up vlc (or whatever else may be your favorite media player)
3. watch in amazement as the network utilization skyrockets, the video is jerky and audio comes out of the completely wrong speakers (and is out of sync with your video, not that it would matter anymore...)
4. do this for half an hour and wait for a lynching mob of coworkers, led by your network administrator, to form at your office door

Software components to address the problem

Three X extensions:

• TIME: allow X clients to send requests to the X server that are not executed immediately but deferred to a defined point in time (actually an interval)
• AUDIO: the name says it; audio playback provides timing information which clients can use to schedule operations
• COMPRESS: allow transmission of compressed audio and video frames; video frames are available as Pictures through the RENDER extension for further compositing, audio data can be further processed through the functions of the AUDIO extension

The AUDIO and TIME extension have been rolled into a single module that is available here.

On top of these low-level building blocks the main part of the architecture consists of:

• a media processing library that can defer media processing to the X server (or alternatively perform in the client)
• a backend for the cairo graphics processing library (to allow compositing of video frames)
• bridges to the gtk and Qt user interface toolkit libraries