Hierarchical browsing and search of large image databases

The advent of large image databases (>10000) has created a need for tools which can search and organize images automatically by their content. This paper focuses on the use of hierarchical tree-structures to both speed-up search-by-query and organize databases for effective browsing. The first part of this paper develops a fast search algorithm based on best-first branch and bound search. This algorithm is designed so that speed and accuracy may be continuously traded-off through the selection of a parameter lambda. We find that the algorithm is most effective when used to perform an approximate search, where it can typically reduce computation by a factor of 20-40 for accuracies ranging from 80% to 90%. We then present a method for designing a hierarchical browsing environment which we call a similarity pyramid. The similarity pyramid groups similar images together while allowing users to view the database at varying levels of resolution. We show that the similarity pyramid is best constructed using agglomerative (bottom up) clustering methods, and present a fast sparse clustering method which dramatically reduces both memory and computation over conventional methods.     

Clustering results of image searches by annotations and visual features

Image on web has become one of the most important information for browsers; however, the large number of results retrieved from images search engine increases the difficulty in finding the intended images. Image search result clustering (ISRC) is a solution to this problem. Currently, the ISRC-based methods separately utilized textual and visual features to present clustering result. In this paper, we proposed a new ISRC method as called Incremental-Annotations-based image search with clustering (IAISC), which adopted annotation as textual features and category model as visual features. IAISC can provide clustering result based on the semantic meaning and visual trail; further, presented by the iteratively structure, a user can obtain the intended image easily. The experimental result shows our method has high precision that the average precision rate is 73.4%; particularly, the precision rate is 96.5% when the user drills down the intended images till the last round. Regarding efficiency, our system is one and a half times as efficient as the previous studies.     

Online image search result grouping with MapReduce-based image clustering and graph construction for large-scale photos

Current image search system uses paged image list to show search results. However, the problems such as query ambiguity make users hard to find search targets in such image list. In this work, we propose an image search result grouping system that summarizes image search results in semantic and visual groups. We use MapReduce-based image graph construction and image clustering methods to deal with scalability problem on this system. By precomputing image graphs and image clusters at offline stage, this system can be efficient at responding user query. The experiments on two large scale Flickr image datasets are conducted for our system. Compared with using single machine, our graph construction method is 69 times faster. We conduct a comprehensive user study to compare our approach with state-of-the-art baseline methods. We find that our approach generates competent image groups with a 2–100 times speeded-up.     

The use of visual search for knowledge gathering in image decision support

This paper presents a new method of knowledge gathering for decision support in image understanding based on information extracted from the dynamics of saccadic eye movements. The framework involves the construction of a generic image feature extraction library, from which the feature extractors that are most relevant to the visual assessment by domain experts are determined automatically through factor analysis. The dynamics of the visual search are analyzed by using the Markov model for providing training information to novices on how and where to look for image features. The validity of the framework has been evaluated in a clinical scenario whereby the pulmonary vascular distribution on Computed Tomography images was assessed by experienced radiologists as a potential indicator of heart failure. The performance of the system has been demonstrated by training four novices to follow the visual assessment behavior of two experienced observers. In all cases, the accuracy of the students improved from near random decision making (33%) to accuracies ranging from 50% to 68%.     

红外小目标图像的分割与聚类分析

天空背景下红外小目标图像的分割与聚类是检测和识别目标过程的预处理部分。首先对图像进行对比度增强处理,并通过模板滤波法去除弱噪声,再运用分割算法把目标和强噪声从背景中分离出来,然后根据聚类得到可能的小目标,最后给出整套处理方法的实验结果和分析。     

An enhanced image quality assessment by synergizing superpixels and visual saliency

Superpixel and saliency-based evaluation methods play important roles in full reference image quality assessment (FR IQA). However, we find that these methods have one complementary principle and three limitations: (1) the weighted maps of superpixel-based methods conflict with the perception of the human visual system; (2) saliency-based methods are inefficient in terms of the block distortion; (3) the general two-direction gradient extraction factor must be extended to be multidirectional. To address these limitations, we propose an enhanced image quality assessment by synergizing superpixels and visual saliency. Specifically, the calculation of a newly proposed framework involves three similarities and two strategies: the saliency, superpixel and multidirectional gradient similarities of the neighborhoods, and the saliency pooling strategy, the fusion strategy of these similarities. Theoretical analysis and experimental results show that the proposed method can effectively address the limitations noted above and outperform the existing methods.     

图像搜索引擎检索模式分析与研究

文中研究如何从HTML文档中提取图片相关信息,保证高效和准确的实现图片检索。在对图像搜索引擎检索模式分析的基础上,提出了若干关键技术,设计并实现了一个基于文本的Web图片搜索引擎,给出了系统的总体结构图．并对获取网页、提取信息、图片抓取、建立索引和提供查询进行了详细的描述,分析了图像搜索引擎的检索模式。     

视觉舒适度的理论模型及其图像研究

以韦伯—费昔勒定律为基础,建立了视觉舒适度的理论模型,利用拟合方法得出四种光环境下视觉舒适度的公式和图像。其结果表明：建立的视觉舒适度的数学模型能较好地反映视觉舒适度的客观规律,并能为节能照明设计提供定量的理论依据。     

基于特征聚类的图像错误检测及掩盖算法

针对现有的大多数图像错误掩盖算法缺乏错误检测能力,在空间域和变换域提出了2个基于特征聚类并结合信息隐藏技术的错误检测和恢复的掩盖算法,将图像DCT变换的直流系数和低频系数按块聚类,把块聚类号作为隐藏信息分别嵌入到像素和中频系数的最低位平面中,通过这些隐藏的块聚类号之间的一致性比较实现了错误块的检测,再用与错误块具有相同类的正常块的中心点数据替代错误块完成错误掩盖.对比实验表明,该算法在平衡隐藏容量、隐写图像质量、掩盖效果和顽健性之间的矛盾上具有优势.     

基于粗糙集的图像聚类分割方法研究

结合粗糙集理论和K-均值聚类算法,提出了一种图像分割方法。将原图像按等价关系进行划分,基于属性约简的概念对不同区域按照不可分辨关系分类。分割结果表明,文中方法是一种有效的图像分割方法,具有良好的鲁棒性。     

Lloyd clustering of Gauss mixture models for image compression and classification

Gauss mixtures have gained popularity in statistics and statistical signal processing applications for a variety of reasons, including their ability to well approximate a large class of interesting densities and the availability of algorithms such as the Baum–Welch or expectation-maximization (EM) algorithm for constructing the models based on observed data. We here consider a quantization approach to Gauss mixture design based on the information theoretic view of Gaussian sources as a “worst case” for robust signal compression. Results in high-rate quantization theory suggest distortion measures suitable for Lloyd clustering of Gaussian components based on a training set of data. The approach provides a Gauss mixture model and an associated Gauss mixture vector quantizer which is locally robust. We describe the quantizer mismatch distortion and its relation to other distortion measures including the traditional squared error, the Kullback–Leibler (relative entropy) and minimum discrimination information, and the log-likehood distortions. The resulting Lloyd clustering algorithm is demonstrated by applications to image vector quantization, texture classification, and North Atlantic pipeline image classification.     

融合纹理特征与螺旋状搜索聚类的超像素分割算法及应用

针对传统SLIC(simple linear iterative clustering)超像素分割算法没有综合考虑图像的纹理信息特征,导致对边缘信息较强和纹理复杂的图像进行超像素分割时,出现边缘检测不灵敏,分割效果不理想的问题.提出了把原图像先经过噪声抑制提取出纹理特征分量,构建以颜色特性、纹理特征和空间位置特征相融合...     

Web and personal image annotation by mining label correlation with relaxed visual graph embedding

The number of digital images rapidly increases, and it becomes an important challenge to organize these resources effectively. As a way to facilitate image categorization and retrieval, automatic image annotation has received much research attention. Considering that there are a great number of unlabeled images available, it is beneficial to develop an effective mechanism to leverage unlabeled images for large-scale image annotation. Meanwhile, a single image is usually associated with multiple labels, which are inherently correlated to each other. A straightforward method of image annotation is to decompose the problem into multiple independent single-label problems, but this ignores the underlying correlations among different labels. In this paper, we propose a new inductive algorithm for image annotation by integrating label correlation mining and visual similarity mining into a joint framework. We first construct a graph model according to image visual features. A multilabel classifier is then trained by simultaneously uncovering the shared structure common to different labels and the visual graph embedded label prediction matrix for image annotation. We show that the globally optimal solution of the proposed framework can be obtained by performing generalized eigen-decomposition. We apply the proposed framework to both web image annotation and personal album labeling using the NUS-WIDE, MSRA MM 2.0, and Kodak image data sets, and the AUC evaluation metric. Extensive experiments on large-scale image databases collected from the web and personal album show that the proposed algorithm is capable of utilizing both labeled and unlabeled data for image annotation and outperforms other algorithms.     

高空视觉图像识别技术下的信息搜集系统优化设计

当前以信号回波反馈为基础的高空信息搜集系统缺少直观性,反馈的信息也无法得到直观的视觉表达,信息采集过程缺陷明显。为了满足新一代高空信息搜集系统的要求,提出以视觉图像识别技术为基础的高空信息搜集系统设计方法。运用ARM视觉图像传感器采集地面的图像信息,采集后的数据经RTL8019AS以太网控制模块传输,S3C44BOX微处理器模块处理,再由CCD图像搜集模块、解码模块再处理后,数据被发到监控中心进行分析之后存入应用服务器。软件部分采用Visual C++编程系统程序,给出了CCD图像搜集模块以及TCP/IP通信模块内部引入的PLC控制器对高空视觉图像识别下的信息搜集优化设计流程。系统经过测试证明其应用性能良好。     

基于红外与可见光图像融合技术发展与性能评价

红外图像可以全天候且不受光照条件影响的根据目标和背景热辐射差异来区分目标和背景。可见光图像可以通过人的视觉系统的高空间分辨率和清晰度来提供景物的质地和结构细节。因此将红外图像和可见光图像融合可以结合两种图像优势,融合后的图像效果预期良好。本文对传统经典方法和目前较新融合方法进行综述。首先回顾了红外和可见光图像的融合方法,其次选取了一些融合图像的性能评价指标,然后选择具有代表性的具体算法进行图像融合,根据融合图像结果获取评测指标,最后根据指标进行分析并对现状进行总结讨论,及对以后的工作发展方向进行展望。     

一种融合IFOA和K-Means聚类的低照度图像分割方法

为改进电气化铁路接触网补偿器监测装置在光照不足时对图像目标区域分割精度较低,无法准确识别入侵异物的问题,采用全局自适应色调映射的方法增强低照度图像,联合改进的果蝇算法与K-Means聚类算法(IFOA-K-Means聚类算法)实现目标区域的准确分割.实验结果表明,该方法对退化图像的分割精度更高,能够充分保持图像的边缘信...     

舰载红外警戒系统目标图像的离群点挖掘算法

针对舰载红外警戒系统目标图像中弱小目标的检测问题,提出了一种基于离群点挖掘的目标检测算法(OBTD)。依据目标与背景在灰度分布上的不同特性,算法将弱小目标视为离群点。分割图像为一系列的子图像,计算子图像中各像素值的局部可达密度,设定阈值挖掘出离群点,得到可能的目标点。算法时间复杂度低,实时性好。试验表明,该算法能有效地检测出图像中的弱小目标,便于进一步的目标识别和跟踪。     

Scheduling of semiconductor test facility via Petri nets and hybridheuristic search

This paper proposes and evaluates two Petri net-based hybrid heuristic search strategies and their applications to semiconductor test facility scheduling. To reduce the setup time, such as the time spent to bring the test facilities to the required temperatures, scheduling multiple lots for each job type together is desirable. Petri nets can concisely model multiple lot sizes for each job, the strict precedence constraints, multiple kinds of resources, concurrent activities and flexible routes. To cope with the complexities for multiple lots scheduling, this paper presents two Petri net-based hybrid heuristic search strategies. They combine the heuristic best-first strategy with the controlled back tracking strategy based on the execution of the Petri nets. The obtained scheduling results are compared and analyzed through a small-size test facility. The better algorithm is also applied to a more sizable facility containing types of resources with a total of 79 pieces and 30 jobs. The future work includes the real-time implementation of the proposed method and scheduling results in real industrial settings     

Feed and fly control of visual scanpaths for foveation image processing

Foveation-based processing and communication systems can exploit a more efficient representation of images and videos by removing or reducing visual information redundancy, provided that the sequence of foveation points, the visual scanpath, can be determined. However, one point that is neglected by the great majority of foveation models is the “noisy” variation of the random visual exploration exhibited by different observers when viewing the same scene, or even by the same subject along different trials. Here, a model for the generation and control of scanpaths that accounts for such issue is presented. In the model, the sequence of fixations and gaze shifts is controlled by a saliency-based, information foraging mechanism implemented through a dynamical system switching between two states, “feed” and “fly.” Results of the simulations are compared with experimental data derived from publicly available datasets.