X射线投影图像中闪烁体缺陷区域的修复
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摘要
针对X射线投影图像中闪烁体缺陷引起的图像伪影,提出一种缺陷提取算法。采用提取极坐标下局部异常点的方法提取缺陷像素。将本底图像(空扫图像)转化为极坐标形式,提取极坐标下的局部异常像素为缺陷像素,从而得到标记出缺陷像素的掩膜图像。将算法应用于仿真图像的缺陷提取,客观数值和主观视觉2个方面的比较结果验证了该算法的有效性。将梯度信息沿等照度线方向扩散实现图像的修复过程,交叉进行各向异性扩散过程以保证清晰度。对系统采集到的不同放大倍率的X射线投影图像进行缺陷提取,并运用BSCB算法对图像进行修复。实验结果表明,修复后图像的质量得到明显改善。
An extraction method is proposed aiming at artifacts caused by scintillation defects in X-ray projection images. Defective pixels are extracted by extracting the local abnormal points. The normal images are transformed into polar coordinate,and the local abnormal points are extracted to get the mask images with marked defective pixels.Objective data and subjective visual comparison of simulation images validate the effectiveness of the extraction algorithm. The process includes the spreading process along the isolux line and the anisotropic diffusion process. The extraction method is applied. BSCB algorithm is restored into different magnifications of X-ray projection images.Experimental results show that the images quality is improved obviously.
An extraction method is proposed aiming at artifacts caused by scintillation defects in X-ray projection images. Defective pixels are extracted by extracting the local abnormal points. The normal images are transformed into polar coordinate,and the local abnormal points are extracted to get the mask images with marked defective pixels.Objective data and subjective visual comparison of simulation images validate the effectiveness of the extraction algorithm. The process includes the spreading process along the isolux line and the anisotropic diffusion process. The extraction method is applied. BSCB algorithm is restored into different magnifications of X-ray projection images.Experimental results show that the images quality is improved obviously.
引文
[1]张定华,黄魁东,程云勇.锥束CT技术及其应用[M].西安:西北工业大学出版社,2010.
[2]张朝宗,郭志平,张朋,等.工业CT技术和原理[M].北京:科学出版社,2009.
[3]单国强,马铭华,沈定中.掺铊碘化铯晶体的生长缺陷[J].人工晶体学报,2000,26(3/4):389.
[4]周贤,刘义伦.X光图像中缺陷的自动提取方法研究[J].光学学报,2006,26(6):1016-1020.
[5]于光辉,卢洪义,朱敏,等.基于相似变换的CT图像缺陷定位方法[J].CT理论与应用研究,2012,21(1):36-42.
[6]曾理,刘玲慧,向才兵.X射线图像缺陷提取方法研究[EB/OL].[2013-09-26].http://cpfd.cnki.com.cn/Article/CPFDTOTAL-CQKJ201005001028.htm.
[7]Criminisi A,Pérez P,Toyama K.Region Filling and Object Removal by Exemplar-based Image Inpainting[J].IEEE Transactions on Image Processing,2004,13(9):1200-1212.
[8]张福美,潘振宽,魏伟波.基于整体变分模型的矢量图像修复[J].计算机工程,2008,34(8):223-225.
[9]李景辉,张晓峰,马燕.纹理合成在图像修复中的应用研究[J].计算机工程,2009,35(7):206-208.
[10]Bertalmio M,Sapiro G,Caselles V,et al.Image Restoration[EB/OL].[2013-09-26].http://dl.acm.org/citation.cfm?id=344972.
[11]廉晓丽,徐中宇,冯丽丽,等.一种新的基于偏微分方程的图像修复[J].计算机工程,2009,35(6):234-236.
[12]李亮,郭树旭,陈国法.基于偏微分方程的图像修复算法[J].吉林大学学报:信息科学版,2012,30(1):62-64.
[2]张朝宗,郭志平,张朋,等.工业CT技术和原理[M].北京:科学出版社,2009.
[3]单国强,马铭华,沈定中.掺铊碘化铯晶体的生长缺陷[J].人工晶体学报,2000,26(3/4):389.
[4]周贤,刘义伦.X光图像中缺陷的自动提取方法研究[J].光学学报,2006,26(6):1016-1020.
[5]于光辉,卢洪义,朱敏,等.基于相似变换的CT图像缺陷定位方法[J].CT理论与应用研究,2012,21(1):36-42.
[6]曾理,刘玲慧,向才兵.X射线图像缺陷提取方法研究[EB/OL].[2013-09-26].http://cpfd.cnki.com.cn/Article/CPFDTOTAL-CQKJ201005001028.htm.
[7]Criminisi A,Pérez P,Toyama K.Region Filling and Object Removal by Exemplar-based Image Inpainting[J].IEEE Transactions on Image Processing,2004,13(9):1200-1212.
[8]张福美,潘振宽,魏伟波.基于整体变分模型的矢量图像修复[J].计算机工程,2008,34(8):223-225.
[9]李景辉,张晓峰,马燕.纹理合成在图像修复中的应用研究[J].计算机工程,2009,35(7):206-208.
[10]Bertalmio M,Sapiro G,Caselles V,et al.Image Restoration[EB/OL].[2013-09-26].http://dl.acm.org/citation.cfm?id=344972.
[11]廉晓丽,徐中宇,冯丽丽,等.一种新的基于偏微分方程的图像修复[J].计算机工程,2009,35(6):234-236.
[12]李亮,郭树旭,陈国法.基于偏微分方程的图像修复算法[J].吉林大学学报:信息科学版,2012,30(1):62-64.