Linear neural network for the solution of limited angle problems in computer-aided tomography

Shun-Him Wong; SzeFong Mark Yau

doi:10.1117/1.482652

1 January 1998 Linear neural network for the solution of limited angle problems in computer-aided tomography

Shun-Him Wong, SzeFong Mark Yau

Journal of Electronic Imaging, Vol. 7, Issue 1, (January 1998). https://doi.org/10.1117/1.482652

The problem of limited angle tomography in which a complete sinogram is not available is considered. This situation arises in many practical applications where tomographic projection over 180 deg is either physically unrealizable or infeasible. When a complete sinogram is not available, it is well known that the reconstructed images using common reconstruction algorithms, such as convolution back-projection (CBP), will have severe streak artifacts. We present a linear artificial neural network to extrapolate the missing part of the sinogram. Once the complete sinogram is obtained via extrapolation, standard reconstruction techniques such as CBP can be used to generate artifact-free reconstructions. The parameters of the neural network are designed using the sampling theory of signals with noncompact spectral support, the knowledge that complete sinograms have bow-tie-shaped spectral support and regularization. It is found that once designed, these parameters are data independent, especially for images of similar nature. For a sinogram with 2N angular views, each having M raysum per view, if 2L views are available, the computational requirement of the neural network is 4MNL only. The proposed neural network is much more efficient than other iterative algorithms, such as the method of projection onto convex sets; the Papoulis-Gerchberg algorithm; and the Clark-Palmer-Lawrence interpolation method; which requires computations of the order of kMNL, where k is the number of iterations.

Citation Download Citation

Shun-Him Wong and SzeFong Mark Yau "Linear neural network for the solution of limited angle problems in computer-aided tomography," Journal of Electronic Imaging 7(1), (1 January 1998). https://doi.org/10.1117/1.482652

Published: 1 January 1998

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available