Cost of in-network adaption of MC-EZBC for universal multimedia access

摘要

A core concept of universal multimedia access is the use of scalable content. The scalable content should be as flexible as possible to achieve the credo of creating the content once and adapting it to fulfill given requirements. As far as flexibility goes wavelet based codecs are superior. A problem which arises is that the adaptation does not necessarily happen on a device which is aware of the codec which was used in content creation. To rectify this non-awareness, MPEG-21 introduced digital item adaptation in part 7 to abstract the bitstream of a given video. This allows in-network adaptation on nodes which are DIA aware to adapt any video stream as long as a DIA description is given. The drawback is that the DIA description must be sent parallel to the original video sequence. In this paper we will look at how a DIA description for a t+2D scalable wavelet codec looks like. We will evaluate the possibilities we have with various description options and we will also look at the overhead generated by the DIA description.