An Intermedia Skew Control System for Multimedia Data Presentation

Delivery of multimedia traffic from distributed sources to a single destination relies on an accurate characterization or guarantee of the behavior of each involved system component. If anticipated bandwidth, delay, and loss characteristics are violated, statistical scheduling approaches fail, resulting in the loss of established source-to-destination synchronization and the introduction of intermedia skew. We propose an intermedia skew control system for accommodating a class of anomalous behaviors including spurious channel overload, data losses due to corruption or congestion control, and variations in source and destination clock rates. The control system is designed to operate independently from the data source, accommodating the data delivery requirements of an arbitrarily corrupted input stream. Intermedia skew, buffer underflow, and buffer overflow are controlled by regulating the playout rate of each stream through frame drop and duplication. This mechanism is used in conjunction with a statistical source pacing mechanism to to provide an overall multimedia transmission and resynchronization system supporting graceful service degradation.