Video compression using structural flow

This paper proposes a new technique in wavelet video compression that exploits the spatiotemporal regularity of the video. A sequence of frames is said to be regular along the directions in which the pixels vary the least. The directions of regularity of a sequence depend on both its motion content and its spatial structure. We model these directions by a 3D vector field, referred as the structural flow. This flow determines the paths of regularity along which the entropy of the data is smaller. We use these paths to construct a special class of wavelet basis, i.e., the 3D orthonormal bandelet basis for the directional decomposition of the sequence. Our experiments on several standard video sequences demonstrate the significant improvement in compression compared to the standard wavelet video coding.