Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)最新文献

{"title":"Carotid Artery Motion Estimation from Sequences of B-mode Ultrasound Images: Effect of Dynamic Range and Persistence","authors":"J. Stoitsis, S. Golemati, D. Perakis, A. Alexandridi, C. Davos, K. Nikita","doi":"10.1109/IST.2006.1650790","DOIUrl":"https://doi.org/10.1109/IST.2006.1650790","url":null,"abstract":"Motion of the carotid artery wall can be quantitatively estimated from sequences of B-mode ultrasound images. Ultrasound scanner settings, including dynamic range and persistence, can affect the appearance of anatomical structures, and consequently, the results of motion analysis. In this paper, the effects of dynamic range and persistence were studied, in an attempt to suggest optimal values for reliable motion analysis. Image sequences were recorded using four different values for dynamic range, namely 0, 48, 66 and 90 dB, and three different values for persistence, namely 0, 5.6 and 50. Radial and axial displacements as well as the correlation coefficients were estimated using block-matching from recordings of about 3 sec duration. The variances of radial and axial displacements were not significantly affected by changes in dynamic range and persistence. The mean value of the correlation coefficient, which is an index of the reliability of motion analysis, was also not significantly affected by these settings. However, an increase in persistence increased the delays between peak radial displacements and cardiac systole. It is suggested that high values of dynamic range (66 or 90 dB) and low values of persistence (0 or 5.6) are used for motion analysis based on block-matching.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114348337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elimination of Gridlines in X-ray Imaging for Mammography","authors":"T. Maruyama, H. Yamamoto","doi":"10.1109/IST.2006.1650785","DOIUrl":"https://doi.org/10.1109/IST.2006.1650785","url":null,"abstract":"Mammography X-ray equipment uses the radiographic grid in order to remove the scatter radiation and to improve image contrast. The gridlines, such as striped lines, appear on the film and the gridlines are considered that diagnostic information may be impaired as an artifact. In this study, we developed the image processing technique which eliminated gridlines on films using digital image processing. We exposed the phantom, improved the gridlines image and detected the ripple components of the gridlines image. We could eliminate the gridlines from the calcifications image by using the ripple components of the gridlines image. By using digital image processing techniques, we could eliminate gridlines and extract the region of calcification. It was suggested that the accuracy of the mammographic diagnosis could be improved.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124027849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Second Order Spread Spectrum Watermarking Scheme Using Multi-Threshold Wavelet Codec","authors":"I. Khan, S. Raza, Dimitrios Alexios Karras, M. Abdullah, F. Butt","doi":"10.1109/IST.2006.1650798","DOIUrl":"https://doi.org/10.1109/IST.2006.1650798","url":null,"abstract":"A second order error resistant watermarking approach based on spread spectrum is presented in this research. At the heart of the proposed solution lies the concept of twice modulation of the watermark sequence and the selection of the host image coef- ficients based on the Multi-Threshold Wavelet Codec (MTWC). DSSS approach has been widely used in the communications to cover the message signal (narrow band) over the large noise signal (wide band). The resulting signal provides excellent low error probability and is hard to detect the message signal. DSSS used with error correcting codes makes it possible to recover the mes- sage even after severe signal distortions. MTW technique helps in determining the actual wavelet coefficients that need to be water- marked so that the watermark sequence is robust.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133230686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Color Restoration of Scanned Book Images for Various Background Colors and Specular Reflections","authors":"H. Ukida, T. Araki, K. Kojima, Y. Nagai, M. Shinoda","doi":"10.1109/IST.2006.1650779","DOIUrl":"https://doi.org/10.1109/IST.2006.1650779","url":null,"abstract":"In this paper, we discuss the method to restore color of a scanned book image taken by an image scanner. Especially, we show the color restoration methods in cases of the achromatic or chromatic background color and the specular book surface. In our proposed method, the background color is extracted as the one with the highest frequency, and the color in the book image is restored by using its pro- files. The specular reflection can be restored by using the saturation profile of the background color or the mathematical model of specular component profile. The color restoration experiments are performed by using various background color images, and we confirm the effec- tiveness of the proposed method.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126787268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A SAR-Based Algorithm for Imaging of Landmines with GPR","authors":"V. Kovalenko, A. Yarovoy, L. Ligthart","doi":"10.1109/IST.2006.1650777","DOIUrl":"https://doi.org/10.1109/IST.2006.1650777","url":null,"abstract":"In this paper we propose a new algorithm for enhancement of imaging of plastic cased antipersonnel landmines using a video-impulse GPR. The algorithm is implemented as a non-linear waveform based signal processor integrated with a SAR focusing procedure. The algorithm constructs a SAR-like image of the subsurface using the outputs of the signal processor. The signal processor searches for presence of reference waveform in raw 1D GPR echo-returns and compresses in time all responses similar to it. Simultaneously, the responses with different waveforms, which presumably correspond to clutter, are suppressed. The shape of the predefined reference waveform depends on the angle at which the imaged point is illuminated. This algorithm is integrated into an automated data processing and mine detection scheme generating a detection list. The reference waveform and other algorithm parameters are determined from training datasets acquired in a controlled environment. The performance of the new algorithm is compared against the performance of the sequence of the signal processor without angle dependency and SAR and against a scheme involving a cross-correlation of the input with the same reference wavelet. The improvement achieved by the suggested algorithm is demonstrated in terms of ROC curves. wavelet is a representation of the target response to the excitation by the probing pulse of the radar and is derived from a set of data acquired in controlled environment conditions. The algorithm is implemented as a two-stage signal processor with a raw A-Scan as an input. The local similarity between the input and the reference wavelet is calculated at the first stage of the processor for each time sample, and the penalty functional is applied to it at the second stage. The output signal of the processor is a range profile, in which position of a target response is marked by a very sharp monopulse, while most of the other reflections are suppressed to nearly zero level. A SAR focusing procedure is applied to the output of the signal processor resulting in subsurface images where the presence of the APM was marked more clearly while some very strong sources of clutter, like pieces of shrapnel or barbed wire were suppressed. However, it has been shown that the target's response wavelet changes with the change of the angle at which it has been illuminated. Due to this, any particular target is marked with highest possible amplitude responses in the output of the PLSM algorithm only for the A-Scans, which correspond to a small range of illumination angles. This shortcoming may diminish the performance of SAR focusing and the following detection. The angle dependency of the reference wavelet can be established either by modeling or from a training dataset but it cannot be readily applied due to an angle ambiguity existing in a time-space C-Scans. More precisely, the illumination angle cannot be tracked in the 3-D domain. That is a wavelet appearing at each time sampl","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115529614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Imaging Systems and Algorithms for the Numerical Characterization of 3D Shapes of Particle Aggregates","authors":"P. Giordano, D. Barrot, J. Corriveau, S. Mandayam, B. Sukumaran","doi":"10.1109/IST.2006.1650794","DOIUrl":"https://doi.org/10.1109/IST.2006.1650794","url":null,"abstract":"The properties of geomaterial aggregates, mainly flow and shear characteristics, are significantly dependent on the shapes of the particles in the mixture. 3D particle models that have been previously developed to quantify this dependence have proved complex and expensive. This paper describes an optical tomography technique for the acquisition of real particle data that can be characterized using 3D shape descriptors. The algebraic reconstruction technique (ART) is used to synthesize 3D particle shapes from 2D tomography projections. Results demonstrating the efficacy of the method on a set of sand mixtures are presented.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129557893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved MRI Restoration by Integrating Bayesian formalism and Support Vector Machines in a Time Delayed priors Framework","authors":"Dimitrios Alexios Karras, Basil G. Mertzios","doi":"10.1109/IST.2006.1650802","DOIUrl":"https://doi.org/10.1109/IST.2006.1650802","url":null,"abstract":"A data acquisition process is needed to form the MR images. Such data acquisition occurs in the spatial frequency (kspace) domain, where sampling theory determines resolution and field of view, and it results in the formation of the kspace matrix. Strategies for reducing image artifacts are often best developed in this domain. After obtaining such a k-space matrix, image reconstruction involves fast multi-dimensional Inverse Fourier transforms, often preceded by data interpolation and re-sampling. Sampling the k-space matrix occurs along suitable trajectories [1,2,3]. Ideally, these trajectories are chosen to completely cover the k-space according to the Nyquist sampling criterion. The measurement time of a single trajectory can be made short. However, prior to initiating a trajectory, return to thermal equilibrium of the nuclear spins needs to be awaited. The latter is governed by an often slow natural relaxation process that is beyond control of the scanner and impedes fast scanning. Therefore, the only way to shorten scan time in MRI when needed, as for instance in functional MRI, is to reduce the overall waiting time by using fewer trajectories, which in turn should individually cover more of k-space through added curvatures. Although, however, such trajectory omissions achieve the primary goal, i.e. more rapid measurements, they entail under-sampling and violations of the Nyquist criterion thus, leading to concomitant problems for image reconstruction. The above mentioned rapid scanning in MRI problem is highly related with two other ones. The first is the selection of the optimal scanning scheme in k-space that is the problem of finding the shape of sampling trajectories that more fully cover the k-space using fewer trajectories. Mainly three such alternative shapes have been considered in the literature and are used in actual scanners, namely, Cartesian, radial and spiral [1], associated with different reconstruction techniques. More specifically, the Cartesian scheme uses the inverse 2D FFT, while the radial and spiral scanning involve the Projection Reconstruction, the linogram or the SRS-FT approaches [1,2,3]. The second one is associated with image estimation from fewer samples in k-space that is the problem of omitting as many trajectories as possible without attaining worse reconstruction results. The main result of such scan trajectories omissions is that we have fewer samples in kspace than needed for estimating all pixel intensities in image space. Therefore, there is infinity of MRI images satisfying the sparse k-space data and thus, the image restoration problem becomes ill-posed. Additionally, omissions usually cause violation of the Nyquist sampling condition. Despite the fact that solutions are urgently needed, in functional MRI for instance, very few research efforts exist in the literature. –The goal of this paper is to present the development of a new image restoration methodology for extracting Magnetic Resonance Images (","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134547385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Assessment of Image Enhancement and Object Detection Methods Applied to Mechanically Scanned Sonar Systems","authors":"S. Repetto, V. Ayala, M. Garofalo, M. Scarpa, A. Trucco","doi":"10.1109/IST.2006.1650789","DOIUrl":"https://doi.org/10.1109/IST.2006.1650789","url":null,"abstract":"In this paper, some efficient methods for acoustic image enhancement and automatic object detection are presented and assessed on a specific class of real data. The aim is to increase the potentiality of mechanically scanned fan-shaped-beam and pencilbeam sonar systems employed during underwater operations. Concerning the fan-shaped-beam sonar system, a set of methods has been assessed that is devoted to increase the visual quality of the generated images. The first step is a scan conversion procedure, to move from a polar coordinate system as that of the sonar to a dense, regular matrix of pixels. An efficient interpolation step, working on the same polar coordinates of the sonar system, has been developed, that performs the computation of the value to assign to every pixel on the basis of the weighted average of the neighbouring acoustic samples. Moreover, a dynamic pixel brightness assignment law, evaluated image by image, is carried out to optimally exploit the available brightness range. The joint application of the interpolation method and the optimised brightness assignment allows one to improve image quality thus providing a simple and effective tool to generate particularly refined acoustic images. Finally, further processing steps allow to reduce typical problems blurring this kind of imaging systems, like speckle noise, multiple echoes and low","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"115 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133454701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photon Counting Imager using CMOS Compatible Photodetectors","authors":"V. Nieminen, J. Kostamovaara, A. Makynen","doi":"10.1109/IST.2006.1650786","DOIUrl":"https://doi.org/10.1109/IST.2006.1650786","url":null,"abstract":"This work describes a CMOS compatible photodetector purposed for a photon counting imager. Several structures have been designed and implemented using standard industrial CMOS technology. First test results are presented in this paper.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124535462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Adaptive Visual Tracking Method Based on Multiple Features","authors":"A. D. Stasio, Michele Ceccarelli","doi":"10.1109/IST.2006.1650774","DOIUrl":"https://doi.org/10.1109/IST.2006.1650774","url":null,"abstract":"Object tracking naturally plays a key role in any visual surveillance system, and there are a number of tracking algorithms for different applications. Here we present an object tracking system based on the Multiple Hypothesis Testing approach. The main characteristic of our approach consists in the development of a probabilistic data association mechanism which makes use of multiple features about each observed objects in the scene. The appearance and disappearance of object is based on a hypothesis matrix. Each matrix element, represents the possibility that a given object at a certain time instant matches another object at a successive time instant. In practice the matching between objects is obtained by comparing Kalman predicted features and observed features between successive time steps. Therefore, our algorithm dynami- cally creates and destroys tracks on the basis of the hypothesis matrix.","PeriodicalId":175808,"journal":{"name":"Proceedings of the 2006 IEEE International Workshop on Imagining Systems and Techniques (IST 2006)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114216281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}