Live-Wire Segmentation with "shortest path"
By Ilan Smoly
What is segmentation?
Approaches with graphs
• Intelligent scissors and Live wire - Optimal path (Dijkstra)
• Binary images posteriori estimation – Min-cut/Max-flow• Seeds – Min-cut/Max-flow with user inputs.
The graph
• Oriented Boundary• Intelligent Scissors
Oriented Boundary
• Intensity• Various gradient magnitude• Orientation-sensitive
Intelligent Scissors
• Laplacian Zero-Crossing• Magnitude:• Gradient Direction
Shortest path with Laplacian cost
Livewire on the Fly
• A pruning of Dikstra• Stops when target is reached
Results
directionality
Magnitude
Power
• No magnitude• No Directionality • No Power
• Directionality = 13 • Power = 30• Magnitude = 43
Discussion
• powerful and efficient tool for image editing and analyzing.
• Medical use• Not reliable for long distance pathways
Improvement
• random long distance relations between pixels
• Adopting the biological model