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1.
XMage is introduced in this paper as a method for partial similarity searching in image databases. Region-based image retrieval is a method of retrieving partially similar images. It has been proposed as a way to accurately process queries in an image database. In region-based image retrieval, region matching is indispensable for computing the partial similarity between two images because the query processing is based upon regions instead of the entire image. A naive method of region matching is a sequential comparison between regions, which causes severe overhead and deteriorates the performance of query processing. In this paper, a new image contents representation, called Condensed eXtended Histogram (CXHistogram), is presented in conjunction with a well-defined distance function CXSim() on the CX-Histogram. The CXSim() is a new image-to-image similarity measure to compute the partial similarity between two images. It achieves the effect of comparing regions of two images by simply comparing the two images. The CXSim() reduces query space by pruning irrelevant images, and it is used as a filtering function before sequential scanning. Extensive experiments were performed on real image data to evaluate XMage. It provides a significant pruning of irrelevant images with no false dismissals. As a consequence, it achieves up to 5.9-fold speed-up in search over the R*-tree search followed by sequential scanning. 相似文献
2.
Automated visual inspection of fabric defects is a challenge due to the diversity of the fabric patterns and defects. Although there are many automated inspection methods of identifying fabric defects, most methods process images containing the fabric patterns classified as the crystallographic group p1 and implicitly assume the fabric patterns are arranged in fixed directions. This paper proposes an automated defect inspection method which calibrates the fabric image and then segments the image into none-overlapped sub-images which are called lattices. Thus, the image is represented by hundreds of lattices sharing some common features instead of millions of unrelated pixels. The defect inspection problem is transformed to comparing the lattice similarity based on the shared features and identifying the defective lattices as the outliers in the feature space. The performance of the proposed method ILS (Isotropic Lattice Segmentation) is evaluated on the databases of images containing fabric patterns arranged orthogonally and arbitrarily. By comparing the resultant images with ground-truth images, an overall detection rate of 0.955 is achieved, which is comparable with the state-of-the-art methods. 相似文献
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常用的基于均方根误差（RMSE）图像保真度准则不能准确地放映一些灰度图像主要敏感细节。本文提出了利用灰度直方图的相似度作为评价重建图像质量的准则。利用JPEG方法对图像进行压缩，并采用直方图相交匹配函数求得图像灰度级的匹配程度。实验结果表明，直方图相交匹配函数是一种有效的图像压缩评测准则。 相似文献
5.
《Information processing & management》2005,41(5):1121-1139
Although there is a growing need for Content-Based Image Retrieval systems, their use is often hampered by significant computational complexity and their inability to explain to their users the reasoning behind the similarity and retrieval processes they employ. This paper introduces Turning Function Difference (TFD), an efficient novel shape-matching method, which is based on the curvature of the shape outline and is translation, rotation and scale invariant. The method produces information about the correspondence of points belonging to the compared shapes that are used during the explanation process. TFD explains its results through an alignment and a visual animation process that highlights the similarities between the model images and each one of the selected images as perceived by the method. The proposed shape-matching method is used in the G Computer Vision (GCV) library, a single-object image retrieval system that utilizes information about the objects’ outlines and explains the reasoning behind the selection of similar images to the user. The implemented system is freely available for download to all interested users. 相似文献
6.
基于Landsat ETM+影像的水体信息综合提取方法 总被引：5，自引：0，他引：5
以Landsat-7 ETM 影像为例,对比分析了常用的水体信息提取方法。针对已有方法无法准确提取河网支流和细小水体信息的缺点,提出了一种水体信息综合提取方法。方法利用谱间关系((TM2 TM3)-(TM4 TM5))和缨帽变换湿度分量TCW建立提取水体的最优空间掩膜,使用最大似然法去除最优空间掩膜中其他的地物信息。在浙江省绍兴及周边区域的实际工作中,本文方法较为完整地提取了研究区的水体信息,包括河网支流和细小水体。提取的相对精度优于其他方法。 相似文献
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8.
基于国产GF-1遥感影像的山区细小水体提取方法研究 总被引：5，自引：0，他引：5
以国产"高分一号"16m遥感图像为数据源,在特克斯县选取两个研究区域,针对山区细小线状河流提取难度较大的问题,使用基于规则的面向对象的方法实现了对山区细小水体的精确化提取。首先,在总结前人选择最优分割尺度的基础上,考虑了各层权重信息,针对某一特定地物,提出了指示最优分割尺度的指标——改进的与邻域绝对均值差分方差比(MRMAS),并由此获取了影像上细小水体的最优分割尺度。其次,为区分水体和山体阴影,构建阴影水体指数SWI=B1+B2-B4,成功剔除了绝大部分阴影信息。最后,利用形态学膨胀滤波及Pavlidis异步细化算法对提取的细小水体进行后处理,最终得到细小河流的矢量化水系图。实验结果表明,该方法可以完整、快速地提取出山区细小线状河流信息,总体精度在90%以上,Kappa系数在85%以上,有效排除阴影等暗色地物的干扰,基本消除椒盐噪声。该研究成果或对国产高分影像处理系统的研发与应用提供一定的科学参考。 相似文献
9.
《Journal of The Franklin Institute》2007,344(3-4):243-256
A new pre-processing method for colour fundus images with adaptive contribution of the red channel is proposed. Based on a condition that is developed in this paper, this method utilises the intensity information from both red and green channels instead of using only the green channel as in the usual practice. The histogram matching is used to modify the histogram of the green channel by using the histogram of the red channel (of the same retinal image) to obtain a new processed image having the advantages of both channels. This method can be used to correct non-uniform illumination in colour fundus images or as a pre-processing step in the automatic analysis of retinal images.Results show that the use of histogram matched (HM) image give better performance than using the green channel image when employing the two-dimensional matched filter to detect retinal blood vessels. At specificity of 90%, in case of abnormal images, sensitivity increased from 76% when using the green channel image to 82% when using the HM image compared with 81% when using the piece-wise threshold probing method. In case of normal images, at the same specificity, the sensitivity obtained when using green channel image or HM image was 87% compared with 88% for the piece-wise threshold probing method. 相似文献
10.
《Information processing & management》2022,59(1):102783
Recently, some copy-move forgeries have made use of homogeneous region(s) in an image with the large-scaling attack(s) to highlight or cover the target objects, which is easy to implement but difficult to detect. Unfortunately, existing Copy-Move Forgery Detection (CMFD) methods fail to detect such kinds of forgeries because they are incapable of extracting a sufficient number of effective keypoints in the homogeneous region(s), leading to inaccuracy and inefficiency in detection. In this work, a new CMFD scheme is proposed: 1) An improved SIFT structure with inherent scaling invariance is designed to enhance the capability of extracting effective keypoints in the homogeneous region. 2). The enhancement of massive keypoints extraction in the homogeneous region incurs a heavy computational burden in feature matching (Note that this is a common issue in all CMFD methods). For this reason, a new Feature Label Matching (FLM) method is proposed to break down the massive keypoints into different small label groups, each of which contains only a small number of keypoints, for significantly improved matching effectiveness and efficiency. 3) Identifying true keypoints for matching is a critical issue for performance. In our work, the Hierarchical Segmentation Filtering (HSF) algorithm is newly proposed to filter out suspicious outliers, based on the statistics on the coarse-to-fine hierarchical segmentations. 4) Finally, the fusion of the coarse-to-fine hierarchical segmentation maps fills the forgery regions precisely. In our experiments, the proposed scheme achieves excellent detection performance under various attacks, especially for the homogeneous region(s) detection under large-scaling attack(s). Extensive experimental results demonstrate that the proposed scheme achieves the best F1 scores and least computational cost in addressing the geometrical attacks on the IMD dataset (a comprehensive dataset), and CMH datasets (most forgery samples under geometric attacks). Compared to existing state-of-the-art methods, the proposed scheme raises at least 20% and 25% in terms of F1 scores under scaling factors of 50%, and 200% in large-scaling sub-datasets of IMD, respectively. 相似文献
11.
Media sharing applications, such as Flickr and Panoramio, contain a large amount of pictures related to real life events. For this reason, the development of effective methods to retrieve these pictures is important, but still a challenging task. Recognizing this importance, and to improve the retrieval effectiveness of tag-based event retrieval systems, we propose a new method to extract a set of geographical tag features from raw geo-spatial profiles of user tags. The main idea is to use these features to select the best expansion terms in a machine learning-based query expansion approach. Specifically, we apply rigorous statistical exploratory analysis of spatial point patterns to extract the geo-spatial features. We use the features both to summarize the spatial characteristics of the spatial distribution of a single term, and to determine the similarity between the spatial profiles of two terms – i.e., term-to-term spatial similarity. To further improve our approach, we investigate the effect of combining our geo-spatial features with temporal features on choosing the expansion terms. To evaluate our method, we perform several experiments, including well-known feature analyzes. Such analyzes show how much our proposed geo-spatial features contribute to improve the overall retrieval performance. The results from our experiments demonstrate the effectiveness and viability of our method. 相似文献
12.
《Information processing & management》2005,41(2):177-194
In this paper, we propose a re-ranking algorithm using post-retrieval clustering for content-based image retrieval (CBIR). In conventional CBIR systems, it is often observed that images visually dissimilar to a query image are ranked high in retrieval results. To remedy this problem, we utilize the similarity relationship of the retrieved results via post-retrieval clustering. In the first step of our method, images are retrieved using visual features such as color histogram. Next, the retrieved images are analyzed using hierarchical agglomerative clustering methods (HACM) and the rank of the results is adjusted according to the distance of a cluster from a query. In addition, we analyze the effects of clustering methods, query-cluster similarity functions, and weighting factors in the proposed method. We conducted a number of experiments using several clustering methods and cluster parameters. Experimental results show that the proposed method achieves an improvement of retrieval effectiveness of over 10% on average in the average normalized modified retrieval rank (ANMRR) measure. 相似文献
13.
摄影测量中标记点编码与解码的方法 总被引：1，自引：0，他引：1
近景摄影测量中,可以在待测物体表面分布一些易于识别的标记点,以提高特征识别的准确性和精度,保证多幅图像阃特征点对应匹配的可靠性.文中讨论了多种标记点的编码与解码,对各种标记点进行了分析,讨论了在不同的情况下使用不同的编码标记点可以起到准确识别和精确定位,提高效率,为图像识打下良好的基础. 相似文献
14.
《Information processing & management》1999,35(5):605-632
Content-based image retrieval systems require the development of relevance feedback mechanisms that allow the user to progressively refine the system's response to a query. In this paper a new relevance feedback mechanism is described which evaluates the feature distributions of the images judged relevant, or not relevant, by the user and dynamically updates both the similarity measure and the query in order to accurately represent the user's particular information needs. Experimental results demonstrate the effectiveness of this mechanism. 相似文献
15.
《Information processing & management》2023,60(1):103106
Teaching images, as an important auxiliary tool in teaching and learning, are fundamentally different from the general domain images. Besides visually similar images being more likely to share common labels, teaching images also face the challenge of visual-knowledge inconsistency, including intra-knowledge visual difference and inter-knowledge visual similarity. To address the above challenges, we present KBHN, a knowledge-aware bi-hypergraph network, which not only considers coarse-grained visual features, but also extracts fine-grained knowledge features that reflect knowledge intention hidden in teaching images. In detail, a visual hypergraph is constructed to connect images with visual similarity. It further enriches coarse-grained visual features by modeling the high-order visual relations among teaching images. Moreover, a knowledge hypergraph based on typical images is built to aggregate images with similar knowledge information, which innovatively extracts fine-grained knowledge features by modeling high-order knowledge correlations between local regions. Furthermore, a multi-head attention mechanism is adopted to fuse visual-knowledge features for enriching image representation. A teaching image dataset is constructed to train and validate our model, which contains 20744 real-world images annotated with 24 knowledge points. Experimental results demonstrate that KBHN, incorporating visual-knowledge features, achieves state-of-the-art performance compared to existing methods. 相似文献
16.
净初级生产力遥感估算模型尺度效应的研究 总被引：2，自引：1，他引：1
提高净初级生产力(NPP)的估算精度,需要充分认识不同空间分辨率的遥感数据对NPP估算结果的
影响差异,即NPP的空间尺度效应问题。本文借鉴了多种成熟的光能利用率NPP模型的优点,同时充分考虑了研
究区生态环境的典型特点,建立了针对研究区域的基于光能利用率原理的植被净初级生产力遥感估算模型。选取
了具有空间尺度代表性的4种遥感数据作为NPP遥感估算模型的输入参数,估算了4种空间分辨率的NPP模拟值,
对比分析了这4种分辨率的土地覆盖类型空间格局的变化和NPP分布情况。结果表明：随着遥感数据空间分辨率
的降低,NPP的模拟值呈逐渐增加的趋势,但其变化的程度差异较大。其中,分辨率由30m降低为1km时,NPP模
拟值变化程度最大,增加了15.7%。 相似文献
17.
Copyright protection of multiple CT images using Octonion Krawtchouk moments and grey Wolf optimizer
《Journal of The Franklin Institute》2023,360(7):4719-4752
This paper proposes a novel Octonion Krawtchouk Moments (OKMs) transform to deal with a set of images in a compact manner, and based on this transform, a local zero-watermarking scheme is proposed to protect the copyright of CT medical images. The scheme first annotates regions of interest (ROIs) on seven medical images and then uses the OKMs of these ROIs to construct a single feature image called zero-watermark. This scheme adopts the gray Wolf Optimizer (GWO) algorithm to have a blind nature and to improve robustness against common image processing manipulations and attacks (zero-watermarking requirements). In addition, our scheme uses the trained U-net (R231) model to reduce the search space for the GWO algorithm and prevent this algorithm from getting stuck in a local optimal solution. The experimental results show that the proposed method is very robust against common image processing manupilations and attacks and has superiority compared with superb other zero-watermarking methods. 相似文献
18.
作为肯尼亚的首都,内罗毕是非洲发展最快的城市之一.本文研究了内罗毕市1988年-2010年城市建成区空间扩展情况.利用1988年Landsat TM、2000年Landsat ETM+以及2010年Landsat TM数据,采用主成分分析与混合分类的方法,提取了1988年-2000年、2000年-2010年、1988年-2010年内罗毕土地覆盖空间变化数据,并分析了城市用地面积扩展的驱动因素.分析结果表明,内罗毕从1988年到2010年总共扩展了141.24km2,扩展面积为1988年城市建成区面积的1.27倍,其中1988年到2000年扩展了60.03km2,2000年到2010年扩展了81.21km2.城市建成区所侵占的地类主要是荒草地和林地,城市建成区的扩展方向是以东西方向为主,并沿着主要交通路线的方向扩展.人口和经济快速增长、便利的交通、地质地形、政府政策是内罗毕城市扩展的驱动因素. 相似文献
19.
基于DTW距离的时序相似性方法提取水稻遥感信息——以泰国为例简 总被引：3，自引：0，他引：3
热带季风区多云多雨的天气条件一直是多光谱遥感探测地表信息的难点之一。本文针对东南亚地区多雨多云的复杂天气条件以及水稻种植灵活的特点,利用MODIS时间序列数据,提出一种基于动态时间弯曲（DTW）距离的相似性判别的土地覆盖分类方法,对泰国东北部地区单、双季稻种植面积进行了遥感提取研究。针对研究区雨季遥感影像像元受到云覆盖影响严重,使用替换法去云,结合S-G滤波方法对计算得到的MODIS09A1数据的NDVI时序数据去噪,再采用DTW距离相似性方法逐像元比较与标准NDVI时间序列的时序相似性,将不同类型所得NDVI相似性值作为模糊分类隶属度参考值对泰国东北部地区单季稻、双季稻进行分类提取面积。最后结合野外采样数据、Google Earth高清遥感影像进行精度验证。结果表明,该方法能够用于针对东南亚多雨多云区水稻种植面积大范围监测。 相似文献
20.
Noriaki Suetake Go Tanaka Jyohei Matsuoka Eiji Uchino 《Journal of The Franklin Institute》2012,349(7):2357-2368
One of the important image processing tasks is to effectively reduce a noise from a digital image while keeping its features intact. In this paper, a new noise removal method for color images corrupted by the mixture of the impulsive and Gaussian noises is proposed. In the proposed method, firstly, a tentative output image, in which the noise is removed almost perfectly, is obtained by using the iterative robust switching vector median-based vector , which is realized by hybridizing the robust switching vector median filter and the vector and is newly proposed here. Then the residual components between the input and the tentative output images are calculated, and image components constituting edges, corner and other image details are extracted from the residual components by using the correlation characteristic in RGB components. Consequently, a final output is obtained by adding the extracted image components into the tentative output image. The effectiveness and the validity of the proposed method are verified by some experiments using the natural color images. 相似文献