Optical Engineering Midwest最新文献

Brownian strings: image segmentation with stochastically deformable models 布朗串:随机变形模型的图像分割

Optical Engineering Midwest Pub Date : 1995-09-01 DOI: 10.1117/12.216784

R. Grzeszczuk, D. Levin

{"title":"Brownian strings: image segmentation with stochastically deformable models","authors":"R. Grzeszczuk, D. Levin","doi":"10.1117/12.216784","DOIUrl":"https://doi.org/10.1117/12.216784","url":null,"abstract":"This paper describes an image segmentation technique in which an arbitrarily shaped contour is deformed stochastically until it fits around an object of interest. The evolution of the contour is controlled by a simulated annealing process which causes the contour to settle into the global minimum of an image-derived 'energy' function which is designed to be small when the contour is near the border of objects similar to the target. The nonparametric energy function is derived from the statistical properties of similar previously segmented images, thereby incorporating prior experience. Since the method is based on a state space search for the contour with the best global properties, it is stable in the presence of image errors which confound segmentation techniques based on local criteria such as connectivity. However, unlike 'snakes' and other active contour approaches, the new method can handle arbitrarily irregular contours in which each inter-pixel crack represents an independent degree of freedom. The method is illustrated by using it to find the brain surface in magnetic resonance head images, to identify the epicardial surface in magnetic resonance cardiac images, and to track blood vessels in angiograms.","PeriodicalId":316044,"journal":{"name":"Optical Engineering Midwest","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128138557","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}

引用次数: 2

Discrete-time model to test links between EEG power and pupil diameter measured by infrared cameras 用离散时间模型测试红外相机测量的脑电图功率与瞳孔直径之间的关系

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216870

A. P. Keegan, S. L. Merritt

引用次数: 6

Micromillimeter wave spectrum analyser using slanted holographic gratings 微毫米波频谱分析仪使用倾斜全息光栅

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216812

Max K. Lee, G. Little

引用次数: 1

Identification of surfaces using discrete triangular approximation of Gaussian curvature 使用高斯曲率的离散三角形近似识别曲面

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216886

Sripriya Ramaswamy, N. Shrikhande

引用次数: 0

Optimized surfaces for second harmonic generation from surface-plasmon polaritons: theory and experiment 表面等离子激元极化产生二次谐波的优化表面:理论与实验

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216816

A. Pipino, R. V. Van Duyne, G. Schatz

{"title":"Optimized surfaces for second harmonic generation from surface-plasmon polaritons: theory and experiment","authors":"A. Pipino, R. V. Van Duyne, G. Schatz","doi":"10.1117/12.216816","DOIUrl":"https://doi.org/10.1117/12.216816","url":null,"abstract":"In connection with recent theoretical predictions, enhancement of optical second harmonic generation (SHG) by diffractive coupling to the silver surface-plasmon polariton (SPP) mode is shown experimentally to be maximized on a biperiodic corrugated surface. Optimized first- order diffractive coupling of incident radiation to the SPP maximizes resonance enhancement of the surface-localized electromagnetic field. Through the nonlinear susceptibility of the silver surface, an SPP-enhanced, evanescent, second harmonic wave is coherently generated which is selectively scattered into the second harmonic specular order by the second spatial harmonic in the surface profile. Biperiodic surfaces with appropriately optimized spatial harmonic composition are shown to provide enhancements in second harmonic relection of up to 104 over the corresponding flat surface response. Using the hologrpahic technique of Breidne et al. (Fourier blaze holography), biperiodic surfaces were fabricated which consisted of a superposition of an 833 nm fundamental and a phase- and amplitude-controlled second spatial harmonic. The results of angle-resolved SHG experiments are presented along with atomic force microscopy line scans of the surface profiles. The effect of coupling to the SPP mode at both the incident and second harmonic frequencies is also discussed.","PeriodicalId":316044,"journal":{"name":"Optical Engineering Midwest","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125280883","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}

引用次数: 1

Improved graphical quality measure for monochrome compressed images 改进了单色压缩图像的图形质量度量

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216866

A. Eskicioglu

引用次数: 5

Real-time detection of laser damage threshold of AR coating of high-power optics 高功率光学AR涂层激光损伤阈值的实时检测

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216854

A. Siahmakoun, Paul W. Southard

引用次数: 1

Elastic registration for videostroboscopic images of the larynx 喉频闪图像的弹性配准

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216882

A. K. Saadah, N. Galatsanos, D. Bless

{"title":"Elastic registration for videostroboscopic images of the larynx","authors":"A. K. Saadah, N. Galatsanos, D. Bless","doi":"10.1117/12.216882","DOIUrl":"https://doi.org/10.1117/12.216882","url":null,"abstract":"Videostroboscopy is an examination method during which a video-recording of the vocal folds can be obtained. This examination is very important because it yields a permanent record of the moving vocal folds and it allows the diagnosis of abnormalities which contribute to voice disorders. In this paper a new algorithm based on simulated annealing (SA) is used to register/match the videostroboscopic images of the larynx. This algorithm operates on the contours representing the vocal folds. The matching process is done through minimizing a cost function, which consists of two parts. The first captures the requirement that the distance between two pixels that are matched should be minimized, while the second part requires the smoothness of the displacement vector field. Four parameters are used to characterize the SA algorithm: 1) the acceptance ratio (chi) , which is set to give a high initial temperature (Tau) 0 to start with, 2) a small positive number (delta) which controls the decrement of the temperature, 3) the length L of the Markov chains that brings the system to equilibrium at each temperature, and 4) a stopping parameter (epsilon) S that defines the final state/configuration of the system. The performance of this matching algorithm is demonstrated on simulated and real videostroboscopic images. It is shown that this algorithm is successful in matching videostroboscopic images when the deformation is severe.","PeriodicalId":316044,"journal":{"name":"Optical Engineering Midwest","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130090887","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}

引用次数: 1

Comparison of rule-based and artificial neural network approaches for improving the automated detection of clustered microcalcifications in mammograms 基于规则和人工神经网络方法在提高乳房x线照片中聚集性微钙化自动检测中的比较

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216875

R. Nagel, R. Nishikawa, J. Papaioannou, M. Giger, K. Doi

{"title":"Comparison of rule-based and artificial neural network approaches for improving the automated detection of clustered microcalcifications in mammograms","authors":"R. Nagel, R. Nishikawa, J. Papaioannou, M. Giger, K. Doi","doi":"10.1117/12.216875","DOIUrl":"https://doi.org/10.1117/12.216875","url":null,"abstract":"Forty-six thousnad women die each year in the US from breast cancer. Mammography is the best method of detecting breast cancer and has been shown to reduce breast cancer mortality in randomized controlled studies. Clustered microcalcifications are often the first sign of breast cancer in a mammogram. The use of a second reader may improve the sensitivity of detecting clustered microcalcifications. Our laboratory has developed a computerized scheme for the detection of clustered microcalcifications that is undergoing clinical evalution. This paper concerns the feature analysis stage of the computerized scheme, which is designed to remove false-computer detections. We have examined three methods of feature analysis: rule-based (the method currently used in the clinical system), an artificial neural network (ANN), and a combined method. To compare the three methods, the false-positive (FP) rate at a sensitivity of 85% was measured on two separate databases. The average number of FPs per image were: 0.54 for rule-based, 0.44 for ANN, and 0.31 for the combined method. The combined method had the highest performance and will be incorporated into the clinical system.","PeriodicalId":316044,"journal":{"name":"Optical Engineering Midwest","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131137636","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}

引用次数: 3

Electronic speckle pattern shearing interferometer using a holographic grating 采用全息光栅的电子散斑剪切干涉仪

Optical Engineering Midwest Pub Date : 1995-08-18 DOI: 10.1117/12.216846

L. Buerkle, C. Joenathan

引用次数: 5