Shape-adaptive coding using binary set splitting with k-d trees

The binary set splitting with k-d trees (BISK) algorithm is introduced. An embedded wavelet-based image coder based on the popular bitplane-coding paradigm, BISK is designed specifically for the coding of image objects with arbitrary shape. While other similar algorithms employ quadtree-based set partitioning to code significance-map information, BISK uses a simpler and more flexible, binary decomposition via k-d trees. Additionally, aggressive discarding of transparent regions is implemented by shrinking sets to the bounding box of their constituent opaque coefficients before further partitioning. Empirical results indicate that the proposed BISK coder consistently yields efficient performance when compared to a variety of other shape-adaptive coders.