Digital Jordan curves

A digital Jordan curve theorem is proved for a new topology defined on Z(2). This topology is compared with the classical Khalimsky and Marcus topologies used in digital topology. We show that the Jordan curves with respect to the topology defined, unlike the Jordan curves with respect to any of the two classical topologies mentioned, may turn at the acute angle pi/4. We also discuss a quotient topology of the new topology. (C) 2006 Elsevier B.V. All rights reserved.