Multivariable feedforward plus feedback control for adapting MPEG video streams to variable channel bandwidth

This paper proposes an algorithm to adapt MPEG video streams to transmission channels with imposed (possibly time-varying) bandwidth, using a smoothing buffer and compression rate control. The adaptation procedure achieves a trade-off between the conflicting aims of maintaining a desired buffer occupancy and minimizing the variations of some given measure of image degradation, while taking into account the strong periodic component of MPEG data streams. The proposed multivariable control, based on a state-space model, operates at group-of-pictures level, and combines feedforward action and linear state feedback