Bidirectional hierarchical anchoring of motion fields for scalable video coding

The ability to predict motion fields at finer temporal scales from coarser ones is a very desirable property for temporal scalability. This is at best very difficult in current state-of-the-art video codecs (i.e., H.264, HEVC), where motion fields are anchored in the frame that is to be predicted (target frame). In this paper, we propose to anchor motion fields in the reference frames. We show how from only one fully coded motion field at the coarsest temporal level as well as breakpoints which signal discontinuities in the motion field, we are able to reliably predict motion fields used at finer temporal levels. This significantly reduces the cost for coding the motion fields. Results on synthetic data show improved rate-distortion (R-D) performance and superior scalability, when compared to the traditional way of anchoring motion fields.