“…Although several trials have been previously made to parallelize watersheds (see [25], [26], [27], [28], [29]), the task is far from being easy since the operation relies on the history of region growth. Various serial methodologies for computing catchment basins with zerowidth watershed lines [7], [13], [21], [22], [23], [33] have been employed for the purpose of parallelization on MIMD computers (see [24]). In each parallel approach, the image is distributed to a virtual grid of processors and partial results are produced by any of the watershed labeling techniques referred above.…”