A videowall build with the Raspberry Pi. Seems to run smooth and the sync looks good as well. Information on how to install PiWall on Raspian and the source code is available here: http://www.piwall.co.uk/
The PTP daemon (PTPd) implements the Precision Time protocol (PTP) as defined by the relevant IEEE 1588 standard. PTP Version 1 implements IEEE-1588-2002, and PTP Version 2 implements IEEE-1588-2008. PTP was developed to provide very precise time coordination of LAN connected computers. The source code is available on github.