Arbitrary ROI-based wavelet video coding

This paper presents a novel arbitrary shape region of interest (ROI) coding for scalable wavelet video codec. The motion information of the ROIs is estimated by macroblock padding and polygon matching. The derived motion vectors are set as the motion trajectory of the samples to generate a one-dimensional temporal signal. This signal is then filtered to reduce the temporal redundancy using motion compensated temporal filtering for arbitrary shape ROI. Compared to traditional non-ROI coding, the reconstructed quality of the ROI coding can be significantly improved at low bit-rates. The efficiency of motion compensated temporal filtering (MCTF) based on arbitrary ROI is also compared with that of the video object coding in MPEG-4. Based on large number of experiments, the ability of the MCTF to reduce the temporal redundancy is demonstrated as better than (or at least comparable to) that of MPEG-4.