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Conference on Unattended Ground Sensor Technologies and Applications VII

作者： Christou, CT Jacyna, GM Mitre Corp Dept W407 Mclean VA 22102 USA

ISBN: (纸本)0819457817

The MITRE Corporation has initiated a three-year internally-funded research program in netted sensors, the first-year effort focusing on vehicle detection for border monitoring. An important component is developing an understanding of the complex acoustic structure of vehicle noise to aid in netted sensor-based detection and classification. This presentation will discuss the design of a high-fidelity vehicle acoustic simulator to model the generation and transmission of acoustic energy from a moving vehicle to a collection of sensor nodes. Realistic spatially-dependent automobile sounds are generated from models of the engine cylinder firing rates. muffler and manifold resonances, and speed-dependent tire whine noise. Tire noise is the dominant noise source for vehicle speeds in excess of 30 miles per hour (MPH). As a result, we have developed detailed models that successfully predict the tire noise spectrum as a function of speed, road surface wave-number spectrum, tire geometry, and tire tread pattern. We have also included realistic descriptions of the spatial directivity patterns for the engine harmonics, muffler, and tire whine noise components. The acoustic waveforms are propagated to each sensor node using a simple phase-dispersive mufti-path model. A brief description of the models and their corresponding outputs is provided.

关键词： Sensors Acoustics Roads Fourier transforms Kinematics Bandpass filters Wave propagation algorithm development Doppler effect Motion models

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Fast algorithm for motion estimation under the varying interframe brightness characteristics

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JOURNAL OF ELECTRONIC IMAGING 2005年第4期14卷 043013.1-043013.7页

作者： Ahmadianpour, F Ahmad, MO Concordia Univ Dept Elect & Comp Engn Montreal PQ H3G 1M8 Canada

A fast two-stage scheme for the search of the motion vectors under varying interframe brightness characteristics, referred to as enhanced motion vectors, is devised. In the first stage of the scheme, a given block and the corresponding blocks in the search window are mapped into the sum-of-pixel value domain, where two subsets of candidate blocks, one consisting the blocks having the DC values closest to the DC value of the block of interest and the other consisting of those having the farthest DC values are selected. In the second stage, the motion vector is determined by employing these subsets and using the mean square error as the matching criterion. Experimental results show that the proposed technique provides a high prediction accuracy with a low computational load. (c) 2005 SPIE and IS&T.

关键词： Motion estimation Video algorithm development Computer engineering Computer simulations

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Robust watermark embedding/detection algorithm for H.264 video

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JOURNAL OF ELECTRONIC IMAGING 2005年第1期14卷 013013.1-013013.9页

作者： Wu, GZ Wang, YJ Hsu, WH Optoelect & Syst Lab Ind Technol Res Inst Hsinchu 300 Taiwan Natl Tsing Hua Univ Dept Elect Engn Hsinchu 300 Taiwan

We present a blind watermark embedding/detection algorithm to embed watermarks into H.264's I pictures. The embedded watermark can survive H.264's compression attacks with more than a 40:1 compression ratio in I pictures. One pair of predicted discrete cosine transform (DCT) coefficients within the blocks of size 4 X 4 are used to embed 1-bit watermark information. The embedding locations of DCT coefficients are switched from lower subbands to higher subbands in a predefined order while the distortions between predicted values and original values are larger than a tolerable bound. With these methods, the embedded watermarks can survive H.264's compression attacks with good invisibility. 2005 SPIE and IS&T.

关键词： Digital watermarking Video Switching Video compression Binary data Image compression Quantization algorithm development Computer programming Roads

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Adaptive and integrated neighborhood-dependent approach for nonlinear enhancement of color images

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JOURNAL OF ELECTRONIC IMAGING 2005年第4期14卷 043006.1-043006.1页

作者： Tao, L Asari, VK Old Dominion Univ Dept Elect & Comp Engn Computat Intelligence & Machine Vis Lab Norfolk VA 23529 USA

A novel image enhancement algorithm called AINDANE ( adaptive and integrated neighborhood dependent approach for nonlinear enhancement) for improving the visual quality of digital images captured under extremely low or nonuniform lighting conditions is proposed. AINDANE is comprised of two separate processes, namely, adaptive luminance enhancement and adaptive contrast enhancement, to provide more flexibility and better control over image enhancement. Adaptive luminance enhancement is a global intensity transformation based on a specifically designed nonlinear transfer function, which is self-tuned by the histogram statistics of the input image. This process largely increases the luminance of darker pixels and compresses the dynamic range of the image at the same time. Adaptive contrast enhancement tunes the intensity of each pixel based on its relative magnitude with respect to the neighboring pixels. This process is also adaptively controlled by the global statistics of the image. A color restoration process, based on the relationship between the spectral bands and the luminance of the original image, is applied to convert the enhanced intensity image back to a color image. (c) 2005 SPIE and IS&T.

关键词： Image enhancement Image processing Image quality Image contrast enhancement Visualization Convolution algorithm development Image compression Color image processing Digital image processing

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On improvement of the computation speed of Otsu's image thresholding

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JOURNAL OF ELECTRONIC IMAGING 2005年第2期14卷 023011.1-023011.1页

作者： Lin, KC Kun Shan Univ Technol Dept Mech Engn Yun Kung City 71003 Tainan County Taiwan

Many previous methods for image thresholding focused on developing automatic algorithms to determine thresholds. However, most of the methods suffer from time-consuming computation for multilevel thresholding. Therefore, a fast and automatic thresholding method is desired for real-time applications. This paper proposes a new and faster method for bilevel as well as multilevel image thresholding. Taking (partial) derivatives of image between-class variance with respect to gray levels develops the proposed method. For bilevel thresholding, a nonlinear equation is derived to solve for an optimal threshold. For multilevel thresholding, a set of nonlinear equations is derived to solve for a set of optimal thresholds. A parameter is introduced to determine the class number for image classification by subjective determination of the ratio of image features to be kept after classification. Statistical performance analysis of the proposed method versus the Baysian classifier is included in this paper. Thresholding computation for the proposed method and Otsu's [N. Otsu, "A threshold selection method from gray-level histograms," IEEE Trans. Syst. Man, Cyber. SMC-9, 62-66 (1979)] is discussed. There are also several examples to illustrate the feasibility of the proposed method and its superiority in computation speed. (c) 2005 SPIE and IS&T.

关键词： Image classification Statistical analysis algorithm development Image processing Bismuth Image segmentation Image analysis Motion analysis Mechanical engineering Roads

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Signature adaptive target detection and threshold selection for constant false alarm rate

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JOURNAL OF ELECTRONIC IMAGING 2005年第3期14卷 033009.1-033009.1页

作者： Crosby, F Naval Surface Warfare Ctr Dahlgren Ctr Panama City FL USA

A constant false alarm rate (CFAR) detection algorithm and a threshold selection algorithm are adapted and developed for use in multiband-image small-target detection. While it is often difficult to predict the spectral signatures of targets, the shape of the target may be known. This detection algorithm exploits geometric target features and spectral differences between the target and the surrounding area. The detection algorithm is derived from a general statistical model of the data with most emphasis on the background. The utility of CFAR algorithms is that the selection of a detection threshold can be made independently of image intensity. However, varied applications of the algorithms show that detection values are dependent on the scene adherence to the model. Achieving a CFAR in applications is very difficult. The threshold for a desired number of false alarms fluctuates with differing backgrounds. By appropriately mapping observations to the model, an automatic threshold selection algorithm is shown. Combining the CFAR-detection algorithm with the threshold selection algorithm produces a reliable constant false alarm rate. (c) 2005 SPIE and IS&T.

关键词： Detection and tracking algorithms Target detection Vegetation Multispectral imaging algorithm development Statistical analysis Image processing Data modeling Land mines Environmental sensing

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Chaotic gray-level image transformation

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JOURNAL OF ELECTRONIC IMAGING 2005年第4期14卷 043001.1-043001.9页

作者： Belkhouche, F Gokcen, I Qidwai, U Tulane Univ Dept Elect Engn & Comp Sci New Orleans LA 70118 USA Gen Elect Global Res Ctr Niskayuna NY USA

We deal with the applications of a class of nonlinear dynamic systems to image transformation and encoding whereby the nonlinear system presents a chaotic or hyperchaotic attractor. Several ways are possible to encode or transform the image using chaos. We develop algorithms for image encoding based on the permutation of the pixel value, position, or both. This approach enables the fast decorrelation of relations among pixels in the initial image in a random-like fashion. We illustrate the use of 1-D, 2-D, and 3-D maps for this purpose. We also use chaotic dynamical systems with a single or two outputs. A discussion of the sensitivity of the algorithms to the keys is followed by the illustration of the algorithms using example images. (c) 2005 SPIE and IS&T.

关键词： Computer programming Complex systems Image compression Dynamical systems Image encryption algorithm development Chaos Diffusion Fractal analysis Nonlinear dynamics

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Bayesian image reconstruction from Fourier-domain samples using prior edge information

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JOURNAL OF ELECTRONIC IMAGING 2005年第4期14卷 043009.1-043009.1页

作者： Denney, TS Reeves, SJ Auburn Univ Auburn AL 36849 USA

We propose the Bayesian image reconstruction with prior edges ( BIRPE) algorithm for reconstructing an image from Fourier-domain samples with prior edge information from a higher resolution image. A major difference between BIRPE and previous methods is that all edges are detected automatically, and no segmentation of the prior image is required. Also, an edge found in the prior image does not need to be confirmed by the observations;smoothing is reduced across the edge if either the prior image or the observations suggest an edge. Simulations and results on magnetic resonance spectroscopic data are presented that demonstrate the effectiveness of the BIRPE method. (c) 2005 SPIE and IS&T.

关键词： Reconstruction algorithms Image restoration Signal to noise ratio Magnetic resonance imaging Image segmentation algorithm development Image processing algorithms and systems Tissues Edge detection Magnetism

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Automatic call number localization in color book images

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JOURNAL OF ELECTRONIC IMAGING 2005年第4期14卷 043017.1-043017.6页

作者： Hu, XF Zhou, Y Ye, QT Shanghai Jiao Tong Univ Sch Mech Engn Shanghai 200030 Peoples R China

An algorithm for automatic localization of call numbers embedded in book images is proposed. The algorithm first detects potential character pixels by computing the difference and the position relation between the maximum and minimum gradient in a local window. These pixels are combined to form connected components ( CCs). Then, CC-based filtering based on the geometry and shape information is performed to eliminate some nontext components, and the retained components are grouped into text lines candidates. Finally, the call number is selected from the text candidates by using a multilayer perceptron ( MLP) classifier. Tests are performed on a set of the images acquired under the different conditions, and experimental results prove that the proposed method is effective. (c) 2005 SPIE and IS&T.

关键词： Image segmentation Video Feature extraction Image filtering algorithm development Image processing Chromium Detection and tracking algorithms Neural networks RGB color model

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Spectral/spatial hyperspectral image compression in conjunction with virtual dimensionality

Spectral/spatial hyperspectral image compression in conjunct...

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Conference on algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery XI

作者： Ramakrishna, B Wang, J Chang, CI Plaza, A Ren, HA Chang, CC Jensens, JL Jensens, JO Univ Maryland Baltimore Cty Remote Sensing Signal & Image Proc Lab Dept Comp Sci & Elect Engn Baltimore MD 21250 USA

ISBN: (纸本)0819457914

Hyperspectral image compression can be performed by either 3-D compression or spectral/spatial compression. It has been demonstrated that due to high spectral resolution hyperspectral image compression can be more effective if compression is carried out spectrally and spatially in two separate stages. One commonly used spectral/spatial compression implements principal components analysis (PCA) or wavelet for spectral compression followed by a 2D/3D compression technique for spatial compression. This paper presents another type of spectral/spatial compression technique, which uses Hyvarinen and Oja's Fast independent component analysis (FastICA) to perform spectral compression, while JPEG2000 is used for 2-D/3-D spatial compression. In order to determine how many independent components are required, a newly developed concept, virtual dimensionality (VD) is used. Since the VD is determined by the false alarm probability rather than the commonly used signal-to-noise ratio or mean squared error (MSE), our proposed FastICA-based spectral/spatial compression is more effective than PCA-based or wavelet-based spectral/spatial compression in data exploitation.

关键词： Image compression Independent component analysis Hyperspectral imaging Principal component analysis Signal to noise ratio Image classification 3D image processing JPEG2000 algorithm development Image analysis

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