  Enhancement is an important step in post-processing digital images for
personal use, in medical imaging, and for object recognition. Most existing
manual techniques rely on region selection, similarity, and/or thresholding for
editing, never really considering the topological structure of the image. In
this paper, we leverage the contour tree to extract a hierarchical
representation of the topology of an image. We propose 4 topology-aware
transfer functions for editing features of the image using local topological
properties, instead of global image properties. Finally, we evaluate our
approach with grayscale and color images.
