首页> 美国卫生研究院文献>Proceedings of the National Academy of Sciences of the United States of America >Discrete Radon transform has an exact fast inverse and generalizes to operations other than sums along lines
【2h】

Discrete Radon transform has an exact fast inverse and generalizes to operations other than sums along lines

机译:离散Radon变换具有精确快速的逆运算并且可以推广到除沿线求和之外的其他运算

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

Götz, Druckmüller, and, independently, Brady have defined a discrete Radon transform (DRT) that sums an image's pixel values along a set of aptly chosen discrete lines, complete in slope and intercept. The transform is fast, O(N2log N) for an N × N image; it uses only addition, not multiplication or interpolation, and it admits a fast, exact algorithm for the adjoint operation, namely backprojection. This paper shows that the transform additionally has a fast, exact (although iterative) inverse. The inverse reproduces to machine accuracy the pixel-by-pixel values of the original image from its DRT, without artifacts or a finite point-spread function. Fourier or fast Fourier transform methods are not used. The inverse can also be calculated from sampled sinograms and is well conditioned in the presence of noise. Also introduced are generalizations of the DRT that combine pixel values along lines by operations other than addition. For example, there is a fast transform that calculates median values along all discrete lines and is able to detect linear features at low signal-to-noise ratios in the presence of pointlike clutter features of arbitrarily large amplitude.
机译:戈茨(Götz),德鲁克米勒(Druckmüller)以及布雷迪(Brady)独立地定义了离散的Radon变换(DRT),该变换将图像的像素值沿一组适当选择的离散线求和,并以斜率和截距完成。变换速度很快,对于N×N图像为O(N 2 log N);它仅使用加法,而不使用乘法或内插,并且它为伴随运算提供了一种快速,精确的算法,即反投影。本文表明,该变换还具有快速,精确(尽管是迭代的)逆函数。逆运算可从DRT复制原始图像的逐像素值,以达到机器精度,而没有伪影或有限的点扩展函数。不使用傅立叶或快速傅立叶变换方法。倒数也可以从采样的正弦图计算得出,并且在存在噪声的情况下条件良好。还介绍了DRT的一般化,它通过除加法以外的操作沿线组合像素值。例如,存在一种快速变换,该变换可以计算所有离散线的中值,并且能够在存在任意大幅度的点状杂波特征的情况下以低信噪比检测线性特征。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号