Anat Levin, Dani Lischinski and Yair Weiss
School of CS&Eng
The Hebrew University of Jerusalem, Israel
Matting and compositing
+
The matting equations
I
i
F
i
i
1(
i
)
B
i
=
x
+
x
Why is matting hard?
Why is matting hard?
Why is matting hard?
Why is matting hard?
I
i
F
i
i
1(
i
)
B
i
Matting is ill posed: 7 unknowns but 3 constraints per
pixel对应于每一个像素有RGB三个通道,三个方程对应7个未
知量
0
]1,0[
1
0
1
Previous approaches
The trimap interface:
•Bayesian Matting (Chuang et al, CVPR01)
•Poisson Matting (Sun et al SIGGRAPH 04)
•Random Walk (Grady et al 05)
Scribbles interface:
•Wang&Cohen ICCV05