- hysteresis thresholding (see the page on edge detection)
- specification of the minimal size of the connected components to be retained
- choice of the connectivity (among 4, 8, 6, 10, 18, 26)
- specification of the maximal number of connected components to be retained (by specifying 1, only the largest connected component is retained)

Original binary image |
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- Labeling the connected components: a different grey level value
(from 1 to the number of connected components) is given to each
component. Here, there are 36 connected components.
Counting the connected components *%test-connexe-pnm ironbin.ppm ironcc.ppm -v* - Filtering the connected components by size: only the connected
components with a size larger than the minimal size are retained .
Here, there are 16 connected components of size larger or equal
to 10.
Selecting the connected components by size *%test-connexe-pnm ironbin.ppm ironccsize=10.ppm -ms 10 -v* - Ordering the connected components by size: only the
**n**largest connected are kept. Labels are given in the order of decreasing sizes (1 is the largest connected component, etc).Ordering the connected components by size *%test-connexe-pnm ironbin.ppm ironccmax=***n***.ppm -ms***n***-v***n**=10**n**=1

Gregoire Malandain Last modified: Mon Feb 12 15:13:15 MET 2001