共查询到20条相似文献,搜索用时 15 毫秒
1.
SIFT算法具有很好的尺度、旋转及光照不变性,因此被广泛应用在计算机视觉的诸多领域.但因其算法复杂、计算时间长,导致实时性不好.在研究SIFT特征描述符生成及匹配过程的基础上,提出一种在匹配过程中降低相似性度量计算时间、提高匹配效率的方法.该方法以棋盘距离和街区距离的线性组合替代欧氏距离来度量特征描述符之间的相似性.实验结果表明:该方法在保证SIFT算法鲁棒性的同时,可以降低匹配时间复杂度. 相似文献
2.
A similarity measure for stereo feature matching 总被引:9,自引:0,他引:9
An approach to stereo feature matching is presented with the introduction of a similarity measure for evaluating and confirming a stereo match. The contributions of this study are reflected in (1) the development of a similarity measure which evaluates a stereo match based on feature locality and gray-level gradient associated with the feature; and (2) the use of a matching procedure that integrates local and global matching strategies based on matching first those features with the highest similarity measure among the set of all highest similarities found locally under confined search spaces, ensuring that each feature is matched with a high degree of certainty. A left-to-right and right-to-left consistency check is used for each feature to comply with the uniqueness constraint and to confirm if a potential match can be declared a correct match 相似文献
3.
4.
5.
一种新的序列图像匹配定位算法 总被引:4,自引:0,他引:4
景象匹配是飞行器导航定位中广泛采用的一项技术,如何提高图像的匹配概率,始终是该项技术中一个值得研究的课题。针对传统的利用单幅实时图像进行匹配时,存在的实时景象图过小、匹配特征不足,从而导致匹配效率过低的问题。文中研究了一种基于归一化灰度相关序列图像匹配算法,利用飞行器飞越匹配区时所得到的序列实时图像,在序列中各单幅图像匹配的基础上,利用一定的规则来综合单幅图像的匹配结果,从而得到最终匹配结果。实验证明,文中方法不仅能显著提高匹配性能,而且有较大的实用性。 相似文献
6.
7.
8.
提出一种基于方向场分析的指纹分类方法.以poincare方法定位指纹中心点,以其为起点,在两个相反的方向上对指纹的纹理方向进行追踪,形成两条方向矢量链,简称为方向链.不同类别指纹具有不同形状的方向链,以方向链总角度差和分支角度差作为分类依据,实现指纹的分类.该方法对指纹的平移和旋转具有无关性,计算量小,易于实现.在NIST-4数据库的50幅图像上测试取得了96%的正确率,在FVC2000的DB1和DB2、FVC2002的DB1和DB2 4个库的800×4幅图像上测试分别取得了89.1%、92.8%、92.3%和89.8%的正确率. 相似文献
9.
针对现有作战决策算法存在的不足,提出了一种新的基于直觉模糊集的作战决策算法.用直觉模糊值表示可行方案指标的不确定信息,综合考虑了方案满足指标的可能性、不满足的可能性和未知的可能性3个方面的因素,给出了直觉模糊决策矩阵的建立方法和可行方案优劣度排序方法.实例及实际应用证明了算法的有效性与可行性. 相似文献
10.
为提高分段弱正交匹配追踪(Stagewise Weak Orthogonal Matching Pursuit,SWOMP)算法的重构质量,改进SWOMP算法的重构性能,提出一种基于模糊阈值的回溯分段弱正交匹配追踪(Backtracking Stagewise Weak Orthogonal Matching Pursuit Al-gorithm based on Fuzzy Threshold,FTB-SWOMP)算法.该算法首先通过采用SWOMP算法初始化选取一些大于门限的原子,在每次迭代过程中引入回溯,采用基于模糊阈值的回溯方式删掉个别错误原子,实现自适应的选取原子来更新支撑集,每次迭代的过程不断更新扩大支撑集,逐步逼近信号的稀疏度.实验结果表明,相同实验条件下,新算法能够以高概率恢复原始一维信号,且重构误差小;对于在二维图像上的应用,新算法仍保证重构时间短的优势,并比原算法具有更好的重构精度. 相似文献
11.
深度包检测技术通过对数据包内容的深入扫描和检测,能够有效识别出隐藏在数据包有效载荷内的非法数据,但该技术存在功耗非常大的缺点。针对该问题,提出了采用Bloom Filter(布隆过滤器)进行字符串模糊匹配方式,利用Bloom Filter将信息流中大部分正常流量过滤掉,从而减轻了后端的字符串精确匹配的压力,降低了系统功耗,大大提高了处理速度。 相似文献
12.
13.
Fu Yusheng Xie Yan Pi Yiming Hou Yinming 《电子科学学刊(英文版)》2006,23(4):598-601
In this letter, a new method is proposed for unsupervised classification of terrain types and man-made objects using POLarimetric Synthetic Aperture Radar (POLSAR) data. This technique is a combination of the usage of polarimetric information of SAR images and the unsupervised classification method based on fuzzy set theory. Image quantization and image enhancement are used to preprocess the POLSAR data. Then the polarimetric information and Fuzzy C-Means (FCM) clustering algorithm are used to classify the preprocessed images. The advantages of this algorithm are the automated classification, its high classification accuracy, fast convergence and high stability. The effectiveness of this algorithm is demonstrated by experiments using SIR-C/X-SAR (Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar) data. 相似文献
14.
15.
Sudipto Dolui Alan Kuurstra Iván C. Salgado Patarroyo Oleg V. Michailovich 《Journal of Visual Communication and Image Representation》2013,24(7):1040-1054
In this paper, the application of non-local means (NLM) filtering on MRI images is investigated. An essential component of any NLM-based algorithm is its similarity measure used to compare pixel intensities. Unfortunately, virtually all existing similarity measures used to denoise MRI images have been derived under the assumption of additive white Gaussian noise contamination. Since this assumption is known to fail at low values of signal-to-noise ratio (SNR), alternative formulations of these measures which take into account the correct (Rician) statistics of the noise are required. Accordingly, the main contribution of the present work is to introduce a new similarity measure for NLM filtering of MRI images, which is derived under bona fide statistical assumptions and proves to posses important theoretical advantages over alternative formulations. The utility and viability of the proposed method is demonstrated through a series of numerical experiments using both in silico and in vivo MRI data. 相似文献
16.
17.
18.
19.
20.
A new detection algorithm (NDA) based on fuzzy cellular neural networks for white blood cell detection. 总被引:1,自引:0,他引:1
White blood cell detection is one of the most basic and key steps in the automatic recognition system of white blood cells in microscopic blood images. Its accuracy and stability greatly affect the operating speed and recognition accuracy of the whole system. But there are only a few methods available for cell detection or segmentation due to the complexity of the microscopic images. This paper focuses on this issue. Based on the detailed analysis of the existing two methods--threshold segmentation followed by mathematical morphology (TSMM), and the fuzzy logic method--a new detection algorithm (NDA) based on fuzzy cellular neural networks is proposed. NDA combines the advantages of TSMM and the fuzzy logic method, and overcomes their drawbacks. With NDA, we can detect almost all white blood cells, and the contour of each detected cell is nearly complete. Its adaptability is strong and the running speed is expected to be comparatively high due to the easy hardware implementation of FCN. Experimental results show good performance. 相似文献