Step Two

gistfile1.cs

//we need to create an instance of a command factory.   
var factory = CommandFactory.Create(); 

//staging all input video streams for concatenation, filtering, and mapping to output
var command = factory.CreateOutputCommand()
                     .WithInput<VideoStream>("c:/foo/bar1.mp4")
                     .WithInput<VideoStream>("c:/foo/bar2.mp4")
                     .WithInput<VideoStream>("c:/foo/bar3.mp4");