Home


Research


Publication


Download


Teaching


Links

Large Scale Inverse Problem and Optimization

.Introduction

We consider the minimization of a smooth convex function regularized by the composite prior models. This problem is generally difficult to solve even each subproblem regularized by one prior model is convex and easy. In this paper, we present two algorithms to effectively solve it. First, the original problem is decomposed into multiple simpler subproblems. Then, these subproblems are efficiently solved by existing techniques in parallel. Finally, the result of the original problem is obtained from the weighted average of solutions of subproblems in an iterative framework. The proposed composite splitting algorithms are applied to the compressed MR image reconstruction and low-rank tensor completion respectively. Numerous experiments demonstrate the superior performance of the proposed algorithm in terms of both the accuracy and computation complexity.


.Download

Junzhou Huang, Shaoting Zhang and Dimitris Metaxas. "Fast Optimization for Mixture Prior Models", In Proc. of the 11th European Conference on Computer Vision, ECCV'2010. [PDF] [CODE]

Junzhou Huang, Shaoting Zhang, Hongsheng Li, Dimitris Metaxas, "Composite Splitting Algorithms for Convex Optimization", Computer Vision and Image Understanding, Volume 115, Number 12, pp. 1610-1622, December 2011.[PDF] [CODE]

Junzhou Huang, Shaoting Zhang, Dimitris Metaxas, "Efficient MR Image Reconstruction for Compressed MR Imaging", Medical Image Analysis, Volume 15, Issue 5, pp. 670-679, October 2011. [CODE]

 

Notice: The codes was tested on Windows and MATLAB 2008. If you have any suggestions or you have found a bug, please contact us via email at jzhuang@uta.edu


Efficient Image Reconstruction in Compressive Sensing MRI

 

Visual Comparison

Figure. Cardiac MR image reconstruction from 20% sampling (a) Original image; (b), (c), (d) (e) and (f) are the reconstructed images by the CG [1], TVCMRI [2], RecPF [3], CSA and FCSA. Their SNR are 9.86, 14.43, 15.20, 16.46 and 17.57 (db). Their CPU time are 2.87, 3.14, 3.07, 2.22 and 2.29 (s).

 

Figure. Brain MR image reconstruction from 20% sampling (a) Original image; (b), (c), (d) (e) and (f) are the reconstructed images by the CG [1], TVCMRI [2], RecPF [3], CSA and FCSA. Their SNR are 8.71, 12.12, 12.40, 18.68 and 20.35 (db). Their CPU time are 2.75, 3.03, 3.00, 2.22 and 2.20 (s).

Performance Comparisons

Figure. Performance comparisons (CPU-Time vs. SNR) on different MR images: a) Cardiac image and (b) Brain image.

Related Sources

[1] SparseMRI

[2] TVMRI

[3] RecPF



Low Rank Tensor Completion

 

Visual Comparison

Figure. Comparisons in terms of visual effects. Color images are: (1)Window; (2) Cherry; (3) Sheep and (4) Fish. The column (a), (b), (c) and (d) correspond to the images before completion, the obtained results by the CGD-LRTC, APG-LRMC and FCSA-LRTC, respectively.

 

Performance Comparisons

Figure. Performance comparisons in terms of the CPU Time and RSE: a)Window image; b) Cherry image; c) Sheep image and (d) Fish image.

 

Related Sources

Low Rank Matrix Completion (SVT-LRMC)

Low Rank Matrix Completion (APG-LRMC)

Low Rank Tensor Completion (CGD-LRTC)