Summary

Multimedia synchronization comprises the definition and the establishment of temporal relationships among audio, video, and other data. The presentation of ‘in sync’ data streams by computers is essential to achieve a natural impression. If data is ‘out of sync’, the human perception tends to identify the presentation as artificial, strange, or annoying. There-fore, the goal of any multimedia system is to present all data without synchronization errors. The achievement of this goal requires a detailed knowledge of the synchronization requirements at the user interface. This paper presents the results of a series of experiments about human media perception. It leads to a first guideline for the definition of a synchronization quality of service. The results show that a skew between related data streams may still let data appear ‘in sync’. It also turned out that the notion of a synchronization error highly depends on the types of media. We use our findings to develop a scheme for the processing of non-trivial synchronization skew between more than two data streams.