In this paper, we propose a software architecture model for the development of elaboration/transcoding modules for structured data. We define a flexible implementation approach which makes it easy to generate modules that deliver good performance. The solution has also the objective to foster high reusability and independen coding of processing and I/O modules. A set of modules developed using his approach have proved o deliver good performance and flexibility in processing MPEG2 Video streams. This paper reports measurements and comparison results with a standard MPEG2 Video decoder, that confirms the potentiality of the approach.