Anisotropic Multi-scale Sparse Learned Bases for Image Compression

This paper proposes a new compression algorithm based on multi-scale learned bases. We first explain the construction of a set of image bases using a bintree segmentation and the optimization procedure used to select the image basis from this set. We then present the sparse orthonormal transforms introduced by Sezer et al.(1) and propose some extensions tending to improve the convergence of the learning algorithm on the one hand and to adapt the transforms to the coding scheme used on the other hand. Comparisons in terms of rate-distortion performance are finally made with the current compression standards JPEG and JPEG2000.