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Image and Signal Processing and Analysis, 2000. IWISPA 2000. Proceedings of the First International Workshop on

Date 14-15 June 2000

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  • IWISPA 2000. Proceedings of the First International Workshop on Image and Signal Processing and Analysis. in conjunction with 22nd International Conference on Information Technology Interfaces. (IEEE Cat. No.00EX437)

    Publication Year: 2000
    Request permission for commercial reuse | PDF file iconPDF (353 KB)
    Freely Available from IEEE
  • Contributors

    Publication Year: 2000, Page(s):xi - xii
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    Freely Available from IEEE
  • Sparse vector linear prediction with near-optimal matrix structures

    Publication Year: 2000, Page(s):235 - 240
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (466 KB)

    Vector linear prediction (VLP) is frequently used in speech and image coding. This paper addresses a technique of reducing the complexity of VLP, named the sparse VLP (sVLP), by decreasing the number of nonzero elements of prediction matrices used for prediction. The pattern of zero and nonzero elements in a matrix, i.e. the matrix structure, is not restricted in the design procedure but is a resu... View full abstract»

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  • An improved null steering algorithm for polarised VLF

    Publication Year: 2000, Page(s):217 - 222
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (368 KB)

    A new algorithm is presented for electronically steering a crossed-loop VLF receiver antenna array to remove interference. The algorithm is a modification of the eigenvector sorting algorithm, which exploits spatial correlation statistics. The new algorithm is intended for situations where the wanted signal is from a transmitter at close range and therefore has horizontal circular polarisation, bu... View full abstract»

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  • Biorthogonal wavelets for intra-frame video coding

    Publication Year: 2000, Page(s):209 - 214
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (564 KB)

    The choice of filter bank in wavelet video compression is a crucial issue that effects both video quality and compression ratio. A series of biorthogonal, symmetric wavelet filters of differing length were evaluated by compressing and decompressing a number of standard video test sequences, using three sets of quantisation parameters. A video codec quality analyser (CQA) is used to assess the subj... View full abstract»

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  • Optimal decomposition for wavelet image compression

    Publication Year: 2000, Page(s):203 - 208
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (676 KB)

    The paper discusses important features of wavelet transform in compression of still images including the extent to which the quality of image is degraded by process of wavelet compression and decompression. A set of wavelet functions (wavelets) for implementation in a still image compression system is examined. The effects of different wavelet functions, image contents and compression ratios are a... View full abstract»

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  • Combined invariants to convolution and rotation

    Publication Year: 2000, Page(s):87 - 92
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (352 KB)

    A new class of moment-based features invariant to image rotation and to convolution with an unknown point-spread function is introduced. These features can be used for the recognition of objects captured by a nonideal imaging system of unknown position and blurring parameters. Practical application to satellite image registration is presented View full abstract»

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  • Local thresholding classified vector quantization with memory reduction

    Publication Year: 2000, Page(s):197 - 202
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (440 KB)

    A new memory reduction method for classified vector quantization (CVQ) is presented. Symmetry reflection, rotation and inversion of edge subimages are used to join appropriate edge classes thus reducing the memory requirements for edge codebooks by 8(4) times for the classifier used in this paper. Besides the memory reduction, our method generates the more robust codebooks thus increasing the PSNR... View full abstract»

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  • Local similarity measures for multimodal image matching

    Publication Year: 2000, Page(s):81 - 86
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (396 KB)

    In this paper we focus on local similarity measures based on Shannon entropy which can be used for multimodal image matching employing deformations. The advantage of our approach is that global similarity or similarity of a larger image region can be computed from the similarities of its constitutive parts or individual voxels. We also discuss the interpolation artefacts in entropy based similarit... View full abstract»

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  • Robust subpixel stereo matching by relaxation of match candidates

    Publication Year: 2000, Page(s):189 - 194
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (408 KB)

    A key issue in performing quantitative measurements in stereoscopic images is the problem of establishing stereo correspondence. For this purpose a novel two step algorithm is presented. The commonly neglected problem of ambiguities is addressed and a solution based on the relaxation of match candidates is introduced. The method comes with the major benefits of a reverse matching step at almost no... View full abstract»

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  • Reconstruction of astronomical images from low-photon image sequence: study for Gaussian displacements

    Publication Year: 2000, Page(s):35 - 40
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (364 KB)

    In the restoration of images from low photon-level data, an estimate of the reconstructed image is often carried out in the general framework of Bayesian statistical estimation. We have developed a new method (Guillaume et al. 1998) for image reconstruction from a sequence of low photon-level and translated astronomical images. We research the maximum a posteriori estimate of the translations to r... View full abstract»

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  • Environment based clustering. A new approach

    Publication Year: 2000, Page(s):75 - 80
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (320 KB)

    There are a variety of problems that require an automatic classification of a set of data. In this sense, clustering techniques have been widely applied, since they are known for forming classes or groups using a predefined similarity measure. This paper defines a new method which, as opposed to the solutions found so far, does not require any previous information about the data to be classified. ... View full abstract»

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  • Prediction-based time-varying filtering for speech enhancement in cellular telephony

    Publication Year: 2000, Page(s):273 - 278
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (564 KB)

    The excitation signal contained in a speech signal and the vocal tract parameters determining the spectral envelope can be extracted by linear prediction (LP). In order to enhance noisy speech signals, time-varying filtering, based on the S-method as a time-frequency analysis tool, is applied to the excitation signal and to the spectral envelope in parallel. This approach is tested with noisy spee... View full abstract»

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  • Effects of image distortion and resolution on 3D reconstruction systems

    Publication Year: 2000, Page(s):183 - 188
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (308 KB)

    Image distortion and insufficient image resolution are significant sources of error that should be taken into account in camera calibration. Calibration point detection (finding the center of marker) and image correction plays very important role during the calibration process. Our results showed that in case of wide angle lenses it is absolutely necessary to correct the image for distortion, if h... View full abstract»

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  • Edge-preserving neural network model for image restoration

    Publication Year: 2000, Page(s):29 - 34
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (476 KB)

    This paper presents a hybrid approach for image restoration with edge-preserving regularization, subband coding, and artificial neural network. The edge information is extracted from the source image as a priori knowledge to recover the details and reduce the ringing artifact of the subband coded image. The multilayer perception model is employed to implement the restoration process. A comparative... View full abstract»

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  • Background-foreground segmentation based on dominant motion estimation and static segmentation

    Publication Year: 2000, Page(s):69 - 74
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (460 KB)

    This paper addresses the problem of image segmentation using motion and luminance information. We use the dominant motion model to calculate both the background and foreground motion in a robust estimation framework and then combine it with the result of static segmentation using the watershed algorithm to segment the foreground from the background. In this paper, the previous pixel-based (or over... View full abstract»

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  • Filter design for the conjugate OFDM-OQAM system

    Publication Year: 2000, Page(s):267 - 272
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (368 KB)

    We present a filter design procedure for a novel multicarrier modulation scheme, the conjugate OFDM-OQAM, which only requires amplitude tailoring of the prototype filter frequency response, regardless of its phase. It achieves good interchannel interference (ICI) and intersymbol interference (ISI) rejection, while still maintaining maximum spectral efficiency and a good time-frequency localization... View full abstract»

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  • Computer vision system for tracking players in sports games

    Publication Year: 2000, Page(s):177 - 182
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (544 KB)

    The development of a computer vision system for tracking players in indoor team games is presented. Several image processing and tracking methods are described, along with camera calibration and lens distortion correction. The output of the system consists of spatio-temporal trajectories of the players, which can be further processed and analyzed by sport experts. In some critical situations the a... View full abstract»

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  • Impedance tapering effects on “low-Q” SAB band-pass active-RC filter

    Publication Year: 2000, Page(s):229 - 234
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (340 KB)

    The design procedure of low-sensitivity active resistance-capacitance (RC) allpole filters, using impedance tapering, has already been published. The low-sensitivity filter sections already described in publications are class 4 (TT-SABB) Sallen and Key (1955) sections. In this paper class 3 (SAB) sections for low pole-Q realization are considered. Impedance tapering is applied on L-sections, which... View full abstract»

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  • Optimal target location in multichannel images

    Publication Year: 2000, Page(s):101 - 106
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (420 KB)

    We propose algorithms for the location of a known target in a multichannel image, optimal for the multichannel model of the image, and optimal for the noise model of the image. We consider two noise models: Gaussian additive, and Gaussian non-overlapping. We show on simulations the improvement due to the multichannel model of the image, compared with the monochannel case. For simulations, the mult... View full abstract»

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  • Change detection in aerial image sequences

    Publication Year: 2000, Page(s):113 - 118
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (320 KB)

    A new method is described for detecting changes in aerial image sequences. An interest operator, sensitive to man-made features, provides cue points for active regions. Several steps are taken to compensate for misalignment, and for differences in illumination by a series of morphological operations, and by using two statistics for measuring the likelihood of a change in any particular region. Can... View full abstract»

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  • Detection and classification of MS using magnetisation transfer ratio images

    Publication Year: 2000, Page(s):127 - 132
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (420 KB)

    Principal component (PCA) and multiple discriminant analysis (MDA) are applied to magnetization transfer ratio (MTR) images in multiple sclerosis (MS). PCA and MDA are used to characterise subtle diffuse changes in MS. PCA is applied to MTR histograms to identify regions of significant variation. These areas are indicated as possible lesion areas. We compare two classifiers to recognise difference... View full abstract»

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  • Polynomial filters for image and video processing

    Publication Year: 2000, Page(s):15 - 26
    Cited by:  Papers (1)  |  Patents (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (904 KB)

    We review the class of polynomial filters and their extensions, first introducing the Volterra (1887, 1913, 1959) series expansion that is at the basis of such filters. The main concepts and properties are given with reference to 1-D signals, while extensions to multidimensional (M-D) signals are then considered. Applications of such filters to image and video processing are also shown View full abstract»

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  • Spatio-temporal image segmentation using optical flow and clustering algorithm

    Publication Year: 2000, Page(s):63 - 68
    Cited by:  Papers (6)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (276 KB)

    Image segmentation is an important and challenging problem in image analysis. Segmentation of moving objects in image sequences is even more difficult and computationally expensive. In this work we propose a technique for spatio-temporal segmentation of medical image sequences based on clustering in the feature vector space. The motivation for the spatio-temporal approach is the fact that motion i... View full abstract»

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  • Analysis of different low complexity nonlinear filters for acoustic echo cancellation

    Publication Year: 2000, Page(s):261 - 266
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (452 KB)

    Linear filters are often employed in most signal processing applications. As a matter of fact, they are well understood within a uniform theory of discrete linear systems. However, many physical systems exhibit some nonlinear behaviour, and in certain situations linear filters perform poorly. One case is the problem of acoustic echo cancellation, where the digital filter employed has to identify a... View full abstract»

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