共查询到10条相似文献,搜索用时 140 毫秒
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F-information measures in medical image registration 总被引:8,自引:0,他引:8
A measure for registration of medical images that currently draws much attention is mutual information. The measure originates from information theory, but has been shown to be successful for image registration as well. Information theory, however, offers many more measures that may be suitable for image registration. These all measure the divergence of the joint distribution of the images' grey values from the joint distribution that would have been found had the images been completely independent. This paper compares the performance of mutual information as a registration measure with that of other F-information measures. The measures are applied to rigid registration of positron emission tomography (PET)/magnetic resonance (MR) and MR/computed tomography (CT) images, for 35 and 41 image pairs, respectively. An accurate gold standard transformation is available for the images, based on implanted markers. The registration performance, robustness and accuracy of the measures are studied. Some of the measures are shown to perform poorly on all aspects. The majority of measures produces results similar to those of mutual information. An important finding, however, is that several measures, although slightly more difficult to optimize, can potentially yield significantly more accurate results than mutual information. 相似文献
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Gholipour A Kehtarnavaz N Briggs R Devous M Gopinath K 《IEEE transactions on medical imaging》2007,26(4):427-451
Functional localization is a concept which involves the application of a sequence of geometrical and statistical image processing operations in order to define the location of brain activity or to produce functional/parametric maps with respect to the brain structure or anatomy. Considering that functional brain images do not normally convey detailed structural information and, thus, do not present an anatomically specific localization of functional activity, various image registration techniques are introduced in the literature for the purpose of mapping functional activity into an anatomical image or a brain atlas. The problems addressed by these techniques differ depending on the application and the type of analysis, i.e., single-subject versus group analysis. Functional to anatomical brain image registration is the core part of functional localization in most applications and is accompanied by intersubject and subject-to-atlas registration for group analysis studies. Cortical surface registration and automatic brain labeling are some of the other tools towards establishing a fully automatic functional localization procedure. While several previous survey papers have reviewed and classified general-purpose medical image registration techniques, this paper provides an overview of brain functional localization along with a survey and classification of the image registration techniques related to this problem. 相似文献
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Mei-Yi Chu Hua-Mei Chen Chih-Yao Hsieh Ting-Hung Lin Hsi-Yue Hsiao Guojun Liao Qi Peng 《Journal of Signal Processing Systems》2009,54(1-3):45-63
In this paper a new approach for non-rigid image registration using mutual information is introduced. A fast parametric method for non-rigid registration is developed by adjusting divergence and curl of an intermediate vector field from which the deformation field is computed using finite-central difference method. Mutual information is newly employed as the similarity measure in the gradient-based cost minimization (or mutual information maximization) of the existing registration framework. The huge amount of data associated with MRI is handled by a fully automated multi-resolution scheme. The adaptive grid system naturally distributes more grids to deprived areas. The positive monitor function disallows grid folding and provides a mean to control the ratio of the areas between the original and transformed domain. The flexibility of the adaptive grid allocation could dramatically reduce processing time with quality preserved. Mutual information facilitates robust registration between different image modalities. Different types of joint histogram estimation are compared and integrated with the system. This scheme is applied on dynamic contrast-enhanced breast MRI, which requires the registration algorithm to be non-rigid, contrast-enhanced features preserving. Preliminary experiments show promising results and great potential for future extension. 相似文献
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Michalis Vrigkas Christophoros Nikou Lisimachos P. Kondi 《Signal Processing: Image Communication》2013,28(5):494-508
The accuracy of image registration plays a dominant role in image super-resolution methods and in the related literature, landmark-based registration methods have gained increasing acceptance in this framework. In this work, we take advantage of a maximum a posteriori (MAP) scheme for image super-resolution in conjunction with the maximization of mutual information to improve image registration for super-resolution imaging. Local as well as global motion in the low-resolution images is considered. The overall scheme consists of two steps. At first, the low-resolution images are registered by establishing correspondences between image features. The second step is to fine-tune the registration parameters along with the high-resolution image estimation, using the maximization of mutual information criterion. Quantitative and qualitative results are reported indicating the effectiveness of the proposed scheme, which is evaluated with different image features and MAP image super-resolution computation methods. 相似文献
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基于归一化互信息的CT-MRI脑图像配准 总被引:1,自引:0,他引:1
医学图像配准研究有非常重要的临床应用价值。针对现在流行的基于最大互信息量的配准方法展开分析和研究。在此基础上对比研究了归一化互信息配准法。通过对一组CT-MR脑图像配准的仿真研究,证明归一化互信息配准法的配准效果很好。特别是在图像重叠区域较小的情况下,比最大互信息配准法效果优越。 相似文献
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Axel Sikora Frank-Peter Pesl Walter Unger Uwe Paschen 《Microelectronics Reliability》2006,46(12):1980-2005
We have examined the various technologies for implementing embedded flash cells. We discuss the technological basics with regard to practical consequences and concentrate on the aspects of reliability of embedded flash cells. The main focus is automotive application because they pose extremely hard requirements in terms of ambient parameters, life-time and programming cycles. Our work is mainly composed of three different parts. The first part gives an insight into the basic technology of embedded flash memory. It specifically concentrates on floating gate devices, which dominate today’s products. This first part is based on a broad analysis of scientific literature and describes the state of the art. The required process steps are presented as well as the test approaches to ensure a high-quality production level. In the second part an overview is given about products actually on the market. Based on this information, the technological characteristics of the different cell architectures are discussed in the third part. 相似文献
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Medical image registration using mutual information 总被引:14,自引:0,他引:14
《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2003,91(10):1699-1722
Analysis of multispectral or multitemporal images requires proper geometric alignment of the images to compare corresponding regions in each image volume. Retrospective three-dimensional alignment or registration of multimodal medical images based on features intrinsic to the image data itself is complicated by their different photometric properties, by the complexity of the anatomical objects in the scene and by the large variety of clinical applications in which registration is involved. While the accuracy of registration approaches based on matching of anatomical landmarks or object surfaces suffers from segmentation errors, voxel-based approaches consider all voxels in the image without the need for segmentation. The recent introduction of the criterion of maximization of mutual information, a basic concept from information theory, has proven to be a breakthrough in the field. While solutions for intrapatient affine registration based on this concept are already commercially available, current research in the field focuses on interpatient nonrigid matching. 相似文献