[Insight-users] Separation of objects using watersheds

[Max Schoebinger]

Hello everyone,

i would like to use the itk::WatershedImageFilter for separating 
connected objects by running the watershed transform on an inverted 
distance tranform of the segmentation. Therefore, i am trying to 
reproduce the results of a simple example given in section "Example 1" 
of the following page:

http://www.mathworks.nl/company/newsletters/news_notes/win02/watershed.html

Unfortunately, the results of the implementation in itk do not seem to 
be correct (at least to me). Please find attached the file input.png and 
result.png, which have been calculated using 0.0 for the flood level and 
threshold parameters. As you can see, the left circle isn't even 
included in the basic segmentation, which is obviously an error assuming 
a flood level of 0.

I have attached the sourcecode, but its just a straightforward 
implementation of calling the itk::WatershedImageFilter.

Any help is appreciated!

Thanks in advance,

Max

-- 
Dipl.-Inform. Med. Max Schöbinger
Deutsches Krebsforschungszentrum       (German Cancer Research Center)
Div. Medical & Biological Informatics          Tel: (+49) 6221-42 2370
Im Neuenheimer Feld 280                        Fax: (+49) 6221-42 2345
D-69120 Heidelberg                       E-Mail: M.Schoebinger at dkfz.de
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