Very low bit-rate wavelet video coding

An image sequence coding scheme for very low bit-rate coding is presented. The scheme is based on spatial redundancy reduction via the new edge-sensitive subband coding method and temporal redundancy reduction via windowed overlapped block-matching motion compensation. In this scheme, only significant regions of difference images are coded. Thus, the computational cost can be kept low. Significant regions are considered to be regions where motion is present (temporal activity) and/or regions where the image is very detailed (spatial activity). The significant regions are determined by an adaptive strategy based on both the motion vectors and an edge map of the current image. The scheme has the main advantage that there are no blocking effects in the decoded images at all due to the properties of both the temporal and the spatial coding used. The overall visual performance of the coding scheme is very good.