[OSC_dev] 4 Byte Padding

[Adrian Freed]

>Why is the OSC messages and addresses padded to multiples of 4 Bytes

For computational efficiency: data will be word aligned in memory of the sender and receiver this way. This means that a copy-free "pass by reference" is possible. This may seem irrelevant in occasional gesture messages but remember that OSC is used for moving multichannel audio and video streams and robot control sequences at Disneyland etc. The benefits are even observable in fast inner loops for oscillators and resonances controlled from OSC messages  ......

http://msdn2.microsoft.com/en-us/library/aa505951.aspx

alignment like this has been a common feature of data formats, e.g.:
http://www.martinreddy.net/gfx/2d/IFF.txt