Statistical Method of Estimation of ESE in CBP

SYNOPTIC ABSTRACT

A linear relationship between the expected squared error (ESE) in reconstruction of images by CBP method, and the covariance kernel of the spatial stochastic process of object function (images) has been established, where the covariance kernel is estimated by sample observations. And a method to estimate the error in reconstruction in practice using the linear relationship is given. When the object covariance kernel is not known an estimate of the covariance kernel is obtained from reconstructed images, and it is used to predict the error. The test cases have been simulated as random images from certain classes of spatial stochastic processes. It is empirically observed that the predicted error in both the cases of known and unknown (estimated) covariance kernel is within reasonable limits of the actual error.

Key Words and Phrases:

• Image Reconstruction
• Stationary stochastic process
• Expected squared error
• Computerized tomography
• Convolution Backprojection Algorithm