The watershed concept and its use in segmentation : a brief history
  The watershed is one of the most used tools in image segmentation. We present how its concept is born and developed over time. Its implementation as an algorithm or a hardwired device evolved together with the technology which allowed it. We present also how it is used in practice, first together with markers, and later introduced in a multiscale framework, in order to produce not a unique partition but a complete hierarchy. 
Fernand Meyer
cs.CV