Concurrent determination of connected components

The design is described of a parallel version of Tarjanʹs algorithm for the determination of equivalence classes in graphs that represent images. Distribution of the vertices of the graph over a number of processes leads to a message passing algorithm. The algorithm is mapped to a shared-memory architecture by means of POSIX threads. It is applied to the determination of connected components in image processing. Experiments show a satisfactory speedup for sufficiently large images.