Special issue on Similarity-based pattern recognition

The goal of this special issue was to solicit and publish high-quality papers that bring a clear picture of the state of the art in this area. We received 71 submissions, confirming that this topic arouses lively interest in the field of Pattern Recognition and Computer Vision. Each paper was reviewed by at least two reviewers, with most being reviewed by three. This meant that we needed the assistance of some 200 reviewers which we thank for their invaluable assistance. Further, each paper was checked out by the editors. Based on the reviews, and giving authors the chance to revise their papers in the light of reviewers, comments, we selected the 10 papers that appear in the current special section, together with five papers that will appear in subsequent regular issues. The papers span a diverse set of methods and applications.