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IEEE Region 10 International conference TENCON

作者： Weiwei Xiao Zhen Ji Xhong Zhang Weiying Wu Faculty of Information Engineering Shenzhen University Shenzhen China

ISBN: (纸本)0780374908

The digital watermarking technique has attracted extensive attention in copyright protection. A watermarking algorithm based on chaotic encryption is proposed. Chaotic sequences are generated through a chaotic map, which is determined by initial condition and parameters. A large number of uncorrelated, random-like, yet deterministic chaotic sequences can be exploited to encrypt the original watermark signal. The encrypted watermark signals are embedded in the image to form a set of watermarked images that will be distributed to different consumers. So we can trace down the Work's distribution according to the extracted watermark. To improve the security of the watermarking algorithm, the watermark is added to the middle frequency coefficients of wavelet domain randomly by exploiting a 2D chaotic system, keeping the parameters of the 2D chaotic system as a private key can prevent the watermark from removing illegally. Superposition randomly improves the robustness and security of the watermarking algorithm. Experimental results demonstrate that the watermarking scheme is robust to typical signal processing operations such as lossy JPEG compression, resizing and cropping and so on.

关键词： Watermarking Chaos Cryptography Signal processing algorithms Security Robustness Copyright protection Frequency Wavelet domain Transform coding

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Using of wavelets and Karhunen-Loeve transform for smoothing and denoising of gated blood pool images

Using of wavelets and Karhunen-Loeve transform for smoothing...

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IEEE Symposium on Nuclear Science (NSS/MIC)

作者： L. Comas O. Blagosklonov R. Sabbah J. Verdenet M. Baud J.-C. Cardot Department of Biophysics and Nuclear Medicine Jean Minjoz University Hospital Besancon France

Gated blood pool imaging (GBP) is well known as an accurate method for evaluation of the main parameters of cardiac function. However, the interpretation of the raw data is difficult because of insufficient images quality due to the approximations applied during the acquisition and to the fact that GBP is done in vivo (heart motion or gamma rays diffusion). Thus images denoising and/or smoothing must be performed. At the same time, image processing must be performed with a maximum of care and precision. Previous studies have been showed excellent performances of wavelet transform for denoising and compression of signals and images. In our department, we routinely use Karhunen-Loeve transform (KLT) to process GBP images. In this study, we revised our previous results concerning the accuracy of spatio-temporal smoothing of image sequences by using of KLT and compared the features of wavelets and of KLT for GBP images denoising. GBP studies using albumin marked with 99mTc (12 MBq/kg) were performed in 30 patients at rest. The image processing was performed in MATLAB version 5.3 on standard PC (PIII-733, 256 Mb RAM). We performed visual analysis of resulting images, analysis of mean image intensities, analysis of gradient images, spatial Fourier analysis and analysis of time-activity curves. The comparison of smoothed images showed that both methods offer adequate quality of images denoising and facilitate the detection of contours. However, the analysis of time-activity curves showed the superiority of KLT; we observed only slight modifications of time-activity curves after the smoothing. In conclusion, although our results showed good accuracy of both methods-wavelets and KLT-for spatial smoothing, only KLT offers possibility of adequate spatial and temporal smoothing of GBP images.

关键词： Karhunen-Loeve transforms Smoothing methods Noise reduction Blood image analysis Performance analysis image denoising image processing image quality In vivo

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一种基于双正交小波分解的自适应数字水印技术

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上海交通大学学报 2002年第6期36卷 792-795页

作者：马仲华余松煜上海交通大学图像通信与信息处理研究所上海200030

提出了一种基于小波域上的自适应图像水印嵌入方法 ,它根据各小波子带的噪声敏感度和视觉掩盖特性 ,将基于 Legendre序列的伪噪声水印添加到图像各小波子带的特定数据上 .实验结果表明 ,本水印具有很好的不可见性 ,并且对图像压缩和噪... 详细信息

提出了一种基于小波域上的自适应图像水印嵌入方法 ,它根据各小波子带的噪声敏感度和视觉掩盖特性 ,将基于 Legendre序列的伪噪声水印添加到图像各小波子带的特定数据上 .实验结果表明 ,本水印具有很好的不可见性 ,并且对图像压缩和噪声干扰具有比

关键词：双正交小波分解自适应数据水印 Legendre序列自适应阈值视觉掩盖图像分解图像重构

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Audio/video compression applications using wavelets

Audio/video compression applications using wavelets

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International Joint conference on Neural Networks (IJCNN)

作者： Yu-Shen Cheng Gen-Dow Huang TECHSOFT TECHNOLOGY Company Limited Taoyuan Taiwan

It is well known that the advantages of wavelet transform are to provide characteristic of multiple resolution and global decomposition that are the significant features for the audio/video compression applications. In this paper, an effective wavelet-based audio/video compression algorithm is presented to provide highly efficient signal compression mechanism with acceptable human visual/hearing perception. Experimental simulations show that the proposed audio/video model can meet the current industrial communication requirements in terms of the processing time and the compression performance. Development of wavelet-based audio/video compression model also includes the consideration of hardware implementation. With this high-performance audio and video codec, it can be employed to develop compact, low power, high-speed, portable, cost-effective, and low-weight video/audio compression multimedia application.

关键词： Video compression image coding Wavelet transforms Bandwidth Humans Audio compression Very large scale integration image reconstruction Quantization Signal resolution

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Saliency map model based on the edge images of natural scenes

Saliency map model based on the edge images of natural scene...

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International Joint conference on Neural Networks (IJCNN)

作者： Kwang-Hwan An Minho Lee Jang-Kyoo Shin School of Electronic and Electrical Engineering Kyungpook National University Daegu South Korea

In this paper, we propose a new saliency map model to find a saliency point based on an edge image rather than a complex natural scene. We use independent component analysis to find a filter that can generate a saliency point from edge information with a gray scale. Computer experimental results show that the proposed saliency map model successfully generates the saliency points, of which the results are very considerable.

关键词： Layout Humans Machine vision Signal processing Intelligent sensors visual system Computer vision Detectors Retina Electronic mail

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Using adaptive edge technique for detecting microaneurysms in fluorescein angiograms of the ocular fundus

Using adaptive edge technique for detecting microaneurysms i...

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Mediterranean Electrotechnical conference (MELECON)

作者： M. Hafez S.A. Azeem Bahgat Group Giza Egypt Department of Electronics & Communications Cairo University Egypt

This paper describes a new digital image-processing algorithm for detecting microaneurysms in fluorescein angiograms of the ocular fundus for diabetic retinopathy patients. Firstly, edges in the image have been detected using the Canny edge detector. Edges which represent vessel segments have been removed from the image. Sobel edge detection is then used for the neighborhoods of the remaining objects. The analysis of size, shape, and energy characteristics of the resultant objects is used to finally segment the microaneurysm from other retinal features. The proposed scheme outperforms currently available techniques in both the sensitivity of microaneurysm detection and the speed of performance.

关键词： image edge detection Detectors image segmentation Retinopathy Digital images Shape Diabetes Algorithm design and analysis Research and development Retina

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Scalable spatial event representation

Scalable spatial event representation

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IEEE International conference on Multimedia and Expo (ICME)

作者： J. Tesic S. Newsam B.S. Manjunath Electrical and Computer Engineering Department University of California Santa Barbara CA USA

This work introduces a conceptual representation for complex spatial arrangements of image features in large multimedia datasets. A novel data structure, termed the spatial event cube (SEC), is formed from the co-occurrence matrices of perceptually classified features with respect to specific spatial relationships. A visual thesaurus constructed using supervised and unsupervised learning techniques is used to label the image features. SECs can be used to not only visualize the dominant spatial arrangements of feature classes but also discover non-obvious configurations. SECs also provide the framework for high-level data mining techniques such as using the generalized association rule approach. Experimental results are provided for a large dataset of aerial images.

关键词： Thesauri Tiles Data mining image color analysis image texture analysis Feature extraction MPEG 7 Standard Unsupervised learning Data processing Scalability

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Vector directional order-statistics for impulse detection

Vector directional order-statistics for impulse detection

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European Signal processing conference (EUSIPCO)

作者： Rastislav Lukáč Department of Electronics and Multimedia Communications Technical University of Košice Park Komensk ého Slovak Republic

In this paper, a new vector directional approach for impulse noise detection and filtering in color images is provided. The novelty of this approach lies in the use of vector order-statistics achieved by the ordering according to the sum of angles between input vector samples, in other words directional information, as the base for impulse detector. Thus, the input samples are separated into two classes such as noise-free samples and corrupted samples. This simple binary decision is performed by the comparison between the operation value and the angle threshold. An importance of the vector directional order-statistics with the smallest angle distances to input samples consists in the determination of the operation value that is given by an angle between the central sample and the mean of `smallest' vector order-statistics. After the separation, only affected samples are processed by basic vector directional filter, whereas noise-free samples are passed to a filter output without change, i.e. the system performs an identity operation. In order to achieve the optimal performance of the proposed method, there is necessary to determine the threshold angle and the number of considered vector order-statistics, too. Since, the proposed adaptive method represents directional processing, the excellent results in the term of the simultaneous impulse noise suppression and signal-details and color chromaticity preservation are desired.

关键词： Vectors Filtering theory Color image color analysis Nonlinear filters Colored noise

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Wandering in VR environments by estimating head pose using an omnicam

Wandering in VR environments by estimating head pose using a...

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Pacific conference on Computer Graphics and Applications

作者： Shigang Li F. Ishizawa N. Chiba Iwate University Morioka Japan

ISBN: (纸本)0769517846

In the walk-through via the Internet, we move a mouse to imitate a walk by our foot (Chen, 1995). Here, we consider the case which maps a real motion to an immersive virtual reality environment. For example, we wander in a computer room as if we do in a museum for watching some arts. The user's head motion at a relative large scale environment is needed to be known for realizing this immersive virtual reality. This research proposes a method of estimating the head motion based upon vision approaches for mapping a head motion to an immersive virtual reality environment. We put fiducial markers around the room to be changed virtually and use an omnidirectional image sensor to observe these markers. By mounting the visual sensor on a helmet, the head motion of a user who wears the helmet can be estimated by processing images captured from the omnidirectional image sensor. Since it has a 360 degree view, it can cope with a large head rotation motion compared with a normal camera. Since a head motion at every time is directly estimated from the observed markers, there is no accumulated errors in our method compared with an inertial sensor.

关键词： Virtual reality Head Motion estimation image sensors Internet Mice Foot Art Large-scale systems Cameras

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Multiple magnification images based micropositioning for 3D micro assembly

Multiple magnification images based micropositioning for 3D ...

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International conference on Control, Automation, Robotics and Vision (ICARCV)

作者： Seok Joo Lee Kyunghwan Kim Deok-Ho Kim Jong-Oh Park Gwi Tae Park Department of Electrical Engineering Korea University SEOUL KOREA Wooshin Mechatronics Co. Ltd Seoul Korea Microsystem Research Center Korea Institute of Science and Technology SEOUL KOREA

ISBN: (纸本)9810483643

This paper presents micropositioning system using feedback of multiple magnification images from CCD cameras mounted on an optical microscope. In order to guarantee of the accurate micropositioning to micro assembly system, high precise sensors are required. But many kinds of sensors, which are used in macro world, have insufficient resolution and size. The visual data from an optical microscope have vast information, however, the single field-of-view of optical microscope essentially limits the workspace of the micromanipulator and the low depth-of-field makes it difficult to handle micro parts. To overcome these problems and increase and precision of micropositioning system, we use multiple magnification images that have same viewpoint. The use of multiple magnification images reduces the time consuming for handling of micro parts and increases precision of micropositioning. We propose this method for micropositioning system.

关键词： Assembly Optical microscopy Optical sensors Lenses Optical feedback Charge coupled devices Charge-coupled image sensors image processing Focusing Cameras

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