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GrabCutInteractive Foreground Extraction
Carsten Rother – Vladimir Kolmogorov – Andrew Blake – Michel Gangnet
GrabCut – Patchworks – Blender Three complementary Tools
GrabCut
Patchworks
Compose
The Goal
User friendly tool for extracting objects in images
Basic Idea
GrabCut - better Quality in less Time
User Input
Result
Magic Wand Magnetic Lasso GrabCut
Colour Contrast Colour & Contrast
How does it work?
Energy minimization based on a novel “MinCut” algorithm
Foreground &Background
Background
Foreground
Background
Colour Space Colour Space
?
User Interface
User Input
User Edit
Result
Rectangle Lasso First Result
Brushes Magnetic Lasso
Energy Minimization
User Edit: Fore- and Background brush
User Interface
Evaluation – Moderately Difficult Images
Initially 100% correct Initially 83% correctInitially 91% correct
GrabCut is superior to Magnetic Lasso if more than 50% of the initial boundary is correct
FirstUser Input
FirstResult
FinalResult
Evaluation - Difficult Images
Camouflage &
Low ContrastAmbiguous colours Thin structure
Initially 75% correct Initially 45% correct Initially 5% correct
GrabCut is superior to Magnetic Lasso if more than 50% of the initial boundary is correct
First User Input
InitialResult
Hard & Soft Extraction
Hard Extraction Soft ExtractionInput
Alpha Matting: Boundary pixels are a combination of Foregroundand Background
Basic IdeaRegularized Transition
“Skin”-Colour Profile
GrabCut
Foreground Mixed Background
Energy minimization with regularization
Soft Extraction Comparison
Input
Bayes Matte
Research
Knockout 2
Photoshop Plug InGrabCut
Comparison
GrabCut - better Quality in less Time
Magic Wand
Photoshop 7
Magnetic Lasso
Photoshop 7
Knockout 2
Photoshop Plug-In
BJ-GraphCut
Research
GrabCut
Application – Home UsersEdit your holiday photos
Application – Home UsersDigital Photomontage
Application – Home UsersDigital Photomontage
Application – Home UsersSell objects on eBay
Application – ProfessionalsAdvertisement
Summary
• GrabCut is a user friendly method for extracting objects in images
• Two major steps - Hard & Soft extraction
• For moderately difficult images GrabCut gives better Quality in less Time
• GrabCut will be presented at SIGGRAPH ‘04
Future Ideas
Fully automatic system using object recognition
GrabCut Foreground
FaceRecognition
Carsten Rother
GrabCut Team
Andrew BlakeVladimir Kolmogorov