Classification and evaluation of filters for wavelet coded videostreams

In this paper, we classify and evaluate filter algorithms developed for a wavelet based video coder. Filter operations convert one representation of a video stream into a different one in which the client is more interested in. Based on our previous work, we have improved the frame rate filter and the dynamic rate shaping filter with preferences (DRS-P) which allows to trade off bandwidth consumption versus visual quality using given user constraints. The user may specify a target bandwidth and his/her preferences and the DRS-P tunes its internal filter operations to match the bandwidth contract and the user preferences based on bandwidth estimates and packet statistics gathered during filter operation. We evaluate different filter settings and combinations with respect to bandwidth and processing time and show that filters can be used to efficiently support real time conferencing scenarios including mobile and low power receivers.