Title :
Convergence of EM image reconstruction algorithms with Gibbs smoothing
Author_Institution :
Dept. of Biomath., California Univ. Sch. of Med., Los Angeles, CA, USA
fDate :
12/1/1990 12:00:00 AM
Abstract :
P.J. Green has defined an OSL (one-step late) algorithm that retains the E-step of the EM algorithm (for image reconstruction in emission tomography) but provides an approximate solution to the M-step. Further modifications of the OSL algorithm guarantee convergence to the unique maximum of the log posterior function. Convergence is proved under a specific set of sufficient conditions. Several of these conditions concern the potential function of the Gibb´s prior, and a number of candidate potential functions are identified. Generalization of the OSL algorithm to transmission tomography is also considered
Keywords :
computerised tomography; radioisotope scanning and imaging; 1-step late algorithm; EM image reconstruction algorithms convergence; Gibb´s prior; Gibbs smoothing; emission tomography; log posterior function; nuclear medicine; Convergence; Image converters; Image reconstruction; Nearest neighbor searches; Parameter estimation; Reconstruction algorithms; Smoothing methods; Sufficient conditions; Tomography; Vectors;
Journal_Title :
Medical Imaging, IEEE Transactions on
