Shepp–Logan phantom

From HandWiki
Image of the Shepp–Logan Phantom

The Shepp–Logan phantom is a standard test image created by Larry Shepp and Benjamin F. Logan for their 1974 paper The Fourier Reconstruction of a Head Section.[1] It serves as the model of a human head in the development and testing of image reconstruction algorithms.[2][3][4]

Definition

The function describing the phantom is defined[1] as the sum of 10 ellipses inside a 2×2 square:

Ellipse Center Major Axis Minor Axis Theta Gray Level
a (0,0) 0.69 0.92 0 2
b (0,−0.0184) 0.6624 0.874 0 −0.98
c (0.22,0) 0.11 0.31 −18° −0.02
d (−0.22,0) 0.16 0.41 18° −0.02
e (0,0.35) 0.21 0.25 0 0.01
f (0,0.1) 0.046 0.046 0 0.01
g (0,−0.1) 0.046 0.046 0 0.01
h (−0.08,−0.605) 0.046 0.023 0 0.01
i (0,−0.605) 0.023 0.023 0 0.01
j (0.06,−0.605) 0.023 0.046 0 0.01

References

See also