The Shepp–Logan phantom is a

standard test image A standard test image is a digital image file used across different institutions to test image processing and image compression algorithms. By using the same standard test images, different labs are able to compare results, both visually and qu ...

created by Larry Shepp and

Benjamin F. Logan Benjamin Franklin "Tex" Logan, Jr. (June 6, 1927 – April 24, 2015) was an American electrical engineer and bluegrass music fiddler. Born in Coahoma, Texas, Logan earned a B.Sc. in electrical engineering at Texas Tech University, then Texas Technol ...

for their 1974 paper ''The Fourier Reconstruction of a Head Section''. It serves as the model of a human head in the development and testing of

image reconstruction Iterative reconstruction refers to iterative algorithms used to reconstruct 2D and 3D images in certain imaging techniques. For example, in computed tomography an image must be reconstructed from projections of an object. Here, iterative recons ...

algorithms.

Definition

The function describing the phantom is defined as the sum of 10

ellipse In mathematics, an ellipse is a plane curve surrounding two focus (geometry), focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special ty ...

s inside a 2×2 square:

Definition

References

See also