计算机工程与应用
計算機工程與應用
계산궤공정여응용
COMPUTER ENGINEERING AND APPLICATIONS
2015年
12期
203-207
,共5页
图像复原%稀疏表示%交替优化%变量分裂%邻近映射
圖像複原%稀疏錶示%交替優化%變量分裂%鄰近映射
도상복원%희소표시%교체우화%변량분렬%린근영사
image deconvolution%sparse representation%alternating optimization%variable splitting%proximity mapping
由于单正则化图像复原算法所利用的先验信息有限,影响了复原图像的质量。为克服此类算法的不足,融入更多的先验信息,改善图像复原的效果。在稀疏表示的理论框架下,提出了一种多正则优化图像复原算法。该算法将图像复原表示为含多正则项的全局优化问题,为有效处理这一复杂的图像复原问题,采用交替优化策略并借助变量分裂将其分解为若干优化子问题。其中,uj+1子问题可微,可直接得到其解析解。不可微的wj+1和vj+1子问题,则通过邻近映射求解。实验过程中对三种不同类型的退化图像进行了复原,所得结果验证了该算法的有效性。与FISTA(Fast Iterative Shrinkage-Thresholding Algorithm)和Split Bregman等单正则化图像复原算法相比,所提算法的复原效果和时间性能更优。
由于單正則化圖像複原算法所利用的先驗信息有限,影響瞭複原圖像的質量。為剋服此類算法的不足,融入更多的先驗信息,改善圖像複原的效果。在稀疏錶示的理論框架下,提齣瞭一種多正則優化圖像複原算法。該算法將圖像複原錶示為含多正則項的全跼優化問題,為有效處理這一複雜的圖像複原問題,採用交替優化策略併藉助變量分裂將其分解為若榦優化子問題。其中,uj+1子問題可微,可直接得到其解析解。不可微的wj+1和vj+1子問題,則通過鄰近映射求解。實驗過程中對三種不同類型的退化圖像進行瞭複原,所得結果驗證瞭該算法的有效性。與FISTA(Fast Iterative Shrinkage-Thresholding Algorithm)和Split Bregman等單正則化圖像複原算法相比,所提算法的複原效果和時間性能更優。
유우단정칙화도상복원산법소이용적선험신식유한,영향료복원도상적질량。위극복차류산법적불족,융입경다적선험신식,개선도상복원적효과。재희소표시적이론광가하,제출료일충다정칙우화도상복원산법。해산법장도상복원표시위함다정칙항적전국우화문제,위유효처리저일복잡적도상복원문제,채용교체우화책략병차조변량분렬장기분해위약간우화자문제。기중,uj+1자문제가미,가직접득도기해석해。불가미적wj+1화vj+1자문제,칙통과린근영사구해。실험과정중대삼충불동류형적퇴화도상진행료복원,소득결과험증료해산법적유효성。여FISTA(Fast Iterative Shrinkage-Thresholding Algorithm)화Split Bregman등단정칙화도상복원산법상비,소제산법적복원효과화시간성능경우。
For single-regularized algorithms, there is limited prior knowledge available for image deconvolution, thus pos-ing negative effects on restored results. To overcome this drawback of single-regularized algorithms, in the framework of sparse representation, this paper proposes a new multi-regularized image deconvolution algorithm which introduces more prior knowledge to improve the quality of restored images. In the proposed algorithm, image deconvolution is cast as a global optimization problem with multiple regularized terms. To solve this complex global optimization problem, the alternating optimization and variable splitting are employed to decompose it into a sequence of subproblems. The analytical solution of u j+1 subproblem can be directly obtained due to its differentiability, whereas for non-differentiable w j+1 and v j+1 sub-problems, the proximity mapping is applied. In the experiment, three kinds of degraded images are successfully restored by the proposed algorithm, which verifies the effectiveness of it. Compared with FISTA(Fast Iterative Shrinkage-Thresh-olding Algorithm)and Split Bregman, the proposed algorithm shows better performances on restored results and speed.