Region Growing
[Image Segmentation]

This group contains segmentation engines based on the propagation of a seed. More...

Classes
class	SoFloodFillThresholdProcessing
	SoFloodFillThresholdProcessing engine More...
class	SoMarkerBasedWatershedProcessing
	SoMarkerBasedWatershedProcessing engine performs a fast determination of the watershed lines. More...

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Detailed Description

This group contains segmentation engines based on the propagation of a seed.

Watershed

The principle of the watershed algorithm is called immersion, and it is based on a simulation of the rise of water from a set of markers. The level p is flooded at a uniform speed from the fronts coming from level p-1 and the local minima appear at level p. A point of the watershed appears when two distinct fronts join.


Figure 1: The watershed principle



Figure 2: Example of how the result depends on the choice of markers

Our watershed implementation is based on:

• L. Vincent and P. Soille. Watersheds in Digital Spaces: An Efficient Algorithm Based on Immersion Simulations. IEEE Transactions on Pattern Analysis and Machine Intelligence archive, Volume 13, Issue 6. June 1991.
• S. Beucher and F. Meyer. The morphological approach to segmentation: the watershed transformation. In E. Dougherty, editor, Mathematical morphology in image processing, chapter 12, pages 433–481. Marcel Dekker, 1993.