Of the various programming paradigms in use today, object-orientation is pr
obably the most successful in terms of industrial take-up and application,
particularly in the field of multimedia. It is therefore unsurprising that
this technology has been adopted by ISO/IEC JTC1/SC24 as the foundation for
a forthcoming International Standard for Multimedia, called PREMO. Two imp
ortant design aims of PREMO are that it be distributable, and that it provi
des a set of media-related services that can be extended in a disciplined w
ay to support the needs of future applications and problem domains. While k
ey aspects of the object-oriented paradigm provide a sound technical basis
for achieving these aims, the need to balance extensibility and a high-leve
l programming interface against the realities of efficiency and ease of imp
lementation in a distributed setting meant that the task of synthesising a
Standard from existing practice was non-trivial. Indeed, in order to meet t
he design aims of PREMO is was found necessary to augment the basic object
infrastructure with facilities and ideas drawn from other programming parad
igms, in particular concepts from constraint management and dataflow. This
paper describes the important trade-offs that have affected the development
of PREMO and explains how these are addressed through the use of specific
programming paradigms.