Active filters: delivering scaled media to mobile devices

Delivering hard quality of service (QoS) guarantees to audio and video flows in the wireless domain is difficult due to large-scale mobility requirements, limited radio resources and QoS fluctuating network conditions. To address this challenge we are developing a QoS-aware middleware platform called mobiware which supports adaptive multimedia applications operating over combined wireline and wireless networks. Mobiware takes as its primary design goal the transport and seamless delivery of audio and video flows to mobile devices with a smooth change of perceptual quality during periods of QoS fluctuation and handoff. Mobiware achieves this goal through the introduction of active filters which can be dispatched during handoff to strategic points in the network (e.g., base stations) to provide media scaling of audio and video flows when and where needed.