Hierarchy of Partitions with Dual Graph Contraction

We present a hierarchical partitioning of images using a pairwise similarity function on a graph-based representation of an image. This function measures the difference along the boundary of two components relative to a measure of differences of component’s internal differences. This definition attempts to encapsulate the intuitive notion of contrast. Two components are merged if there is a low-cost connection between them. Each component’s internal difference is represented by the maximum edge weight of its minimum spanning tree. External differences are the cheapest weight of edges connecting components. We use this idea to find region borders quickly and effortlessly in a bottom-up ’stimulus-driven’ way based on local differences in a specific feature, like as in preattentive vision. The components are merged ignoring the details in regions of high-variability, and preserving the details in low-variability ones.