MediaLisp a system Design for Multimedia Augmented Transition Network in Lisp

To describe media streams played in parallel, we adopt the operator |||. A parallel is a tuple of variable length surrounded by parenthesis with the first element is |||. For example, to represent presentation of media streams x1, x2 and x3 palyed in parallel, we can use: (||| x1 x2 x3). Parallel allows nested structures, such that each element can be

• 
  A single media stream
  
• 
  A sequence of media streams
  
• 
  A parallel of media streams
  

The property set of Parallel contains "Name" and "Duration" with regarding system preserved properties.

The time duration is the maximum all time duration among all contained streams within it. The temporal relationship among streams within a sequence can be obtained by simply applying "meet" relationship sequentially over all contained media streams. For example, given a sequence (||| x1 x2 x3 x4 x5), then the time duration of the sequence is

(max )