Modeling of motion classified VBR video codecs

The authors use a motion adaptive variable-bit-rate (VBR) video codec and propose a motion classified model to represent the characteristics of various classes of motion activities. The codec switches between interframe, motion compensated, and intraframe coding corresponding to low, medium, and high motions and scene changes, respectively. The model captures the motion of various video scenes and the codec structure by providing the statistics of VBR-coded video´ traffic through a first-order composite autoregressive process with three motion classes. The parameters of this model are derived from a VBR-coded sample video sequence such that the bit rate distribution and the autocorrelation in bit rates of two successive frames are matched. The validity and accuracy of the model are verified. Using this model, the characteristics of aggregated traffic sources are discussed