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991.
带状图像交叉区域的骨架求解算法 总被引:4,自引:2,他引:2
交叉区域的求解技术是图像骨架化中的难点,在基于无向图的图像整体骨架表示模型及算法的基础上,提出了图像交叉区域(如X形、K形等)的骨架求解算法,它根据图像交叉区域在无向图中的位置和邻接关系确定图像交叉区域的形状,并根据几何近似原理,用多边形近似方法对不同形状的交叉区域进行求解,算法充分利用图像的拓扑信息,具有速度快,了等优点,并得到了实际应用。 相似文献
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As the hot line in NP-hard problems research in recent years, backbone analysis is crucial for phase transition, hardness, and algorithm design. Whereas theoretical analysis of backbone and its applications in algorithm design are still at a begin- ning state yet, this paper took the quadratic assignment problem (QAP) as a case study and proved by theoretical analysis that it is NP-hard to find the backbone, i.e., no algorithm exists to obtain the backbone of a QAP in polynomial time. Results of this paper showed that it is reasonable to acquire approximate backbone by inter- section of local optimal solutions. Furthermore, with the method of constructing biased instances, this paper proposed a new meta-heuristic -- biased instance based approximate backbone (BI-AB), whose basic idea is as follows: firstly, construct a new biased instance for every QAP instance (the optimal solution of the new instance is also optimal for the original one); secondly, the approximate backbone is obtained by intersection of multiple local optimal solutions computed by some existing algorithm; finally, search for the optimal solutions in the reduced space by fixing the approximate backbone. Work of the paper enhanced the research area of theoretical analysis of backbone. The meta-heuristic proposed in this paper provided a new way for general algorithm design of NP-hard problems as well. 相似文献
997.
A self-recovery fragile watermarking scheme for image authentication with superior localization 总被引:4,自引:0,他引:4
To address the problems of the inferior localization and high probability of false rejection in existing self-recovery fragile watermarking algorithms, this paper proposes a new self-recovery fragile watermarking scheme with superior localization, and further discusses the probability of false rejection (PFR) and the probability of false acceptance (PFA) of the proposed scheme. Moreover, four measurements are defined to evaluate the quality of a recovered image. In the proposed algorithm, the original image is divided into 2×2 blocks to improve localization precision and decrease PFR under occurrence of random tampering. The PFR under occurrence of region tampering can be effectively decreased by randomly embedding the watermark of each block in conjunction with a novel method of tamper detection. Compared with the current self-recovery fragile watermarking algorithms, the proposed scheme not only resolves the tamper detection problem of self-embedding watermarking, but also improves the robustness against the random tampering of self-embedding watermarking. In addition, the subjective measurements are provided to evaluate the performance of the self-recovery watermarking schemes for image authentication. 相似文献
998.
何立民 《单片机与嵌入式系统应用》2008,(10):5-8
嵌入式应用系统是一个有计算机内核的智能化电子系统。集成电路的超长寿命、计算机的软件介入与智能化的控制能力,决定了嵌入式应用系统全新的可靠性设计观念。这些新观念是:基于出错概率的多值可靠性、确定应用系统的可靠性等级、建立应用系统的可靠性模型、应用系统的本质可靠性设计与可靠性控制设计。 相似文献
999.
Learning a Maximum Margin Subspace for Image Retrieval 总被引:1,自引:0,他引:1
Xiaofei He Deng Cai Jiawei Han 《Knowledge and Data Engineering, IEEE Transactions on》2008,20(2):189-201
One of the fundamental problems in Content-Based Image Retrieval (CBIR) has been the gap between low-level visual features and high-level semantic concepts. To narrow down this gap, relevance feedback is introduced into image retrieval. With the user-provided information, a classifier can be learned to distinguish between positive and negative examples. However, in real-world applications, the number of user feedbacks is usually too small compared to the dimensionality of the image space. In order to cope with the high dimensionality, we propose a novel semisupervised method for dimensionality reduction called Maximum Margin Projection (MMP). MMP aims at maximizing the margin between positive and negative examples at each local neighborhood. Different from traditional dimensionality reduction algorithms such as Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA), which effectively see only the global euclidean structure, MMP is designed for discovering the local manifold structure. Therefore, MMP is likely to be more suitable for image retrieval, where nearest neighbor search is usually involved. After projecting the images into a lower dimensional subspace, the relevant images get closer to the query image; thus, the retrieval performance can be enhanced. The experimental results on Corel image database demonstrate the effectiveness of our proposed algorithm. 相似文献
1000.
Subband Synthesis for Color Filter Array Demosaicking 总被引:1,自引:0,他引:1
Li Chen Kim-Hui Yap Yu He 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2008,38(2):485-492
This paper presents a new algorithm for demosaicking images captured through a color filter array (CFA). The objective of the CFA demosaicking is to render a full color image from the mosaicked image. This is commonly achieved by estimating the missing color information from the surrounding observed pixels. In this paper, we integrate the observation that color images have a strong intrachannel spatial correlation in low-frequency components and a dominant interchannel correlation in the high- frequency components. A new framework is proposed to utilize this information where the missing pixels in each color channel are estimated from the wavelet subbands. A modified median-filtering operation is then applied in the subband domain. The algorithm is adaptive and produces superior full-resolution images when compared with other methods. 相似文献