I/O-Efficient Contour Tree Simplification

We present an I/O-efficient version of an algorithm for simplifying contour trees of two- and three-dimensional scalar fields described by Carr et al. [7]. Our algorithm uses optimal \({\mathcal{O}}(Sort(N))={\mathcal{O}}(\frac{N}{B}\log_{M/B} \frac{N}{B})\) I/Os, where N is the size of the contour tree, M the size of main memory and B the disk block size.