Guest Editorial: Scale Space and Variational Methods

Linking the concept of "scale" in filtering images with a Gaussian kernel to "time" in diffusing (later: evolving) an image driven by the so-called heat equation, a Partial Differential Equation (PDE), has started a fruitful pollination of these two areas. Nowadays, more than 55 years after Iijima's groundbreaking concept, researchers for both communities still benefit from each other. In this special issue we collected 8 papers representing state-of-the-art research covering both areas.