Sampling From the Medial Axis Presented by Rahul Biswas April 23, 2003 CS326A: Motion Planning.
Appearance Shock Grammar for Fast Medial Axis Extraction from...
Transcript of Appearance Shock Grammar for Fast Medial Axis Extraction from...
-
Appearance Shock Grammar for Fast Medial Axis Extraction from Real Images
Charles-Olivier Dufresne Camaro
Stavros TsogkasMorteza Rezanejad Kaleem Siddiqi Sven Dickinson
-
Medial Axis Transform (MAT)
Blum, 1967
MAT: Binary shapes AMAT: Natural scenes
Tsogkas & Dickinson, 2017
-
AMAT limitations
• Invalid topologies;
• “Thick” structures;
• Disconnected branches;
• Slow (~6.5min for 400x400 image).
-
Shock graph theory
Application of shock grammar
31
11
1 1
Type 3 shock
Type 1 shock
3
1
11
#
φφ
11
φφ
Shock graph
-
Medial axis extraction begins with a seed…
-
Medial axis extraction begins with a seed…
-
…which is then grown into medial branches.
-
…which is then grown into medial branches.
-
…which is then grown into medial branches.
-
…which is then grown into medial branches.
-
…which is then grown into medial branches.
-
…which is then grown into medial branches.
-
Results
Ground truth ASG (this work)AMAT (State-of-the-art)
F1 = 0.434 F1 = 0.522
t = 393 s t = 35 s 10x speed up!
~9% gains!
-
Applications
Interactive segmentation
Painterly renderingConstrained image editing
Scene retrieval
-
Code available at: github.com/CharloCamaro/ASG
https://github.com/CharloCamaro/ASG