A Model of Regularization Parameter Determination in Low-Dose X-Ray CT Reconstruction Based on Dictionary Learning

Algorithm 1

Workflow of the developed algorithm.

Determination of
Initialize , and .
While the stopping criterion is not satisfied, do
(1) Implement the OSC algorithm for acceleration;
(2) Extract patches from the intermediate image ;
(3) Update the dictionary by K-SVD algorithm;
(4) Update the sparse coding by OMP algorithm;
(5) Update the image by (25) with ;
Output the final image and relative error calculated by (26).
When the iteration is stopped, determine by (27).
Image Reconstruction
Initialize , and , is determined in former step.
While the stopping criterion is not satisfied, do
(1) Implement the OSC algorithm for acceleration;
(2) Extract patches from the intermediate image ;
(3) Update the dictionary by K-SVD algorithm;
(4) Update the sparse coding by OMP algorithm;
(5) Update the image by (23), ;
Output the final reconstruction.