It all started in July 2012 when we noticed that the presentation equipment being used for publicising our work, within the renewable energy sector, was not impressive enough to do the science justice. As anyone who works in the public sector will appreciate, especially in the current economic climate, budgets are tight and any money that is available is spent on essentials. Even though our day jobs are heavily technology orientated we still find ourselves keen home computing enthusiasts and as we had just received our first Raspberry Pi computers, we decided to see just what these little wonders could do.

We started off, as everyone does, trying to use the standard Linux tools like vlc, vncviewer, gstreamer, xdmx etc but we only had partial success because of the limited resources of the ARM CPU used within the Raspberry Pi. After seeing the hello_video example supplied by the Raspberry Pi Foundation, we turned our attention to the GPU. Using omxplayer as a base we added the features we required and then looked into how we could synchronise all the screens. This turned out to be a simple case of throttling the transmission of video packets to the normal display frame rate and use the network to continuously re-synchronise the screens. It worked first time and after wrestling with 5 Raspberry Pi’s scattered on a desk with cables everywhere we decided to build a self contained 4 screen system housed in a standard PC case, utilising a normal PC power supply. This remains to be our main test system, even today.

We continued to develop and enhance the software for a few more weeks before we revealed our achievements to our bosses. They were initially very keen and supportive and asked us to provide a 9 screen system ready for a recruitment evening. The system performed perfectly and we began to explore the possibility of developing the idea as some kind of spin out from CCFE. We continued to expand the capabilities of the system by adding desktop mirroring. This operates in a similar way to VNC but has a different network mechanism and uses the GPU for acceleration - utilising an alternative API to the one used by omxplayer so that we can use the two systems together. After testing the system extensively for many months we decided to publicise our success, so on the 5th of April 2013 we were privileged to be the featured news item on thewww.raspberrypi.org site. Soon after this announcement, CCFE decided that getting involved with the video wall industry was incompatible with its core activity - to develop nuclear fusion energy. Since then, we have been enhancing the code, sorting out license information, forming a company, planning for support, writing documentation, designing a case, the list is almost endless but we’re on our way ;-)