Principle of the FLST

Idea: Any shape contains a regional extremum without hole (leaf of the tree). Every regional extremum contains a pixel that is a local extremum.
Principle: During a scan of the image, we initiate a process of region growing at each local extremum met. The region growing stops when the region cannot be a regional extremum, or is one but with a hole.
Interpretation: Extraction of terminal branches
 

Summer School on Mathematical Problems in Image Processing, Trieste, Italy, September 4th-18th 2000