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81.
透视图象的三维实体几何复原   总被引:1,自引:0,他引:1  
对于未知透视参数的图象,如何获得较精确的原实体三维几何构形,本文推导了几个线段逆变换关系式,给出一个有效的方法,实现复杂组合体透视图象的三维重建,文中给出几个实例。  相似文献   
82.
陈文艺  赵宏 《光电工程》1994,21(6):26-31
结合实时法全息干涉计量和数字图象处理技术,提出了一种溶液扩散系数的自动测量系统。在干涉图的处理中,采用了相位检测和曲线拟合技术,得到了亚象素的测量精度。  相似文献   
83.
钢中非金属夹杂物显微评级方法的定量化探讨   总被引:2,自引:0,他引:2  
刘继雄  汪美蔷 《钢铁研究》1994,(6):40-42,58
应用IBAS系列图像分析系统,对建立一套与国家标准GB10561─89兼容的钢中非金属夹杂物显微评级方法的自动化和定量化标准作了可行性分析,结果表明建立这套标准是切实可行的。  相似文献   
84.
It is well known that angles in composite parts contract as they are cooled down from the curing temperature, this is often referred to as spring-in. It is caused mainly by the significantly different thermal contractions and cure shrinkage's experienced between the fibre direction and the through-thickness direction during the manufacturing process. A number of works have reported on the spring-in of straight angle composite parts. However, little has been done to investigate the distortion of curved flanged composite parts, which will distort differently owing to the introduction of the additional curvature, thus constraint.

In the present work, the distortion of the circularly curved flanged laminates is studied numerically. The finite element method is used to predict the processing-induced distortion of the part with two different approaches. In the first approach, the shear angles of the composite plies are predicted by a draping analysis. The effect of the fibre shearing on the mechanical properties of the laminates is considered in the model used to predict the distortion. The second simplified approach assumes that the in-plane properties of the laminates are isotropic. The results obtained by these two approaches are compared with those obtained experimentally.  相似文献   

85.
Disparity field and depth map coding for multiview 3D image generation   总被引:3,自引:0,他引:3  
In the present paper techniques are examined for the coding of the depth map and disparity fields for stereo or multiview image communication applications. It is assumed that both the left and right channels of the multiview image sequence are coded using block- or object-based methods. A dynamic programming algorithm is used to estimate a disparity field between each stereo image pair. Depth is then estimated and occlusions are optionally detected, based on the estimated disparity fields. Spatial interpolation techniques are examined based on the disparity/depth information and the detection of occluded regions using either stereoscopic or trinocular camera configurations. It is seen that the presence of a third camera at the transmitter site improves the estimation of disparities, the detection of occlusions and the accuracy of the resulting spatial interpolation at the receiver. Various disparity field and depth map coding techniques are then proposed and evaluated, with emphasis given to the quality of the resulting intermediate images at the receiver site. Block-based and wireframe modeling techniques are examined for the coding of isolated depth or disparity map information. Further, 2D and 3D motion compensation techniques are evaluated for the coding of sequences of depth or disparity maps. The motion fields needed may be available as a byproduct of block-based or object-based coding of the intensity images. Experimental results are given for the evaluation of the performance of the proposed coding and spatial interpolation methods.  相似文献   
86.
本文通过有关理论依据和试验数据,着重阐述了在显像(示)管测试中,阴极像中心黑洞状缺陷产生的原因以及消除这种缺陷的处理方法。通过这种处理方法处理过的显像(示)管,其整体质量水平(尤其是真空度)将会得到明显的提高。  相似文献   
87.
本文研究了医学图象小波变换系数的统计特征。根据医学图象的特点,提出了基于小波变换的医学图象编码方法。实验表明,这种方法具有较好的压缩编码性能,优于JPEG标准。同时,它支持逐次浮现式传输,从而能满足医学图象存储、通信、检索的需要。  相似文献   
88.
The logarithmic image processing (LIP) model is amathematical framework based on abstract linear mathematicswhich provides a set of specific algebraic and functionaloperations that can be applied to the processing of intensityimages valued in a bounded range. The LIP model has been provedto be physically justified in the setting of transmitted lightand to be consistent with several laws and characteristics ofthe human visual system. Successful application examples havealso been reported in several image processing areas, e.g.,image enhancement, image restoration, three-dimensional imagereconstruction, edge detection and image segmentation.The aim of this article is to show that the LIP model is atractable mathematical framework for image processing which isconsistent with several laws and characteristics of humanbrightness perception. This is a survey article in the sensethat it presents (almost) previously published results in arevised, refined and self-contained form. First, an introductionto the LIP model is exposed. Emphasis will be especially placedon the initial motivation and goal, and on the scope of themodel. Then, an introductory summary of mathematicalfundamentals of the LIP model is detailed. Next, the articleaims at surveying the connections of the LIP model with severallaws and characteristics of human brightness perception, namelythe brightness scale inversion, saturation characteristic, Weber'sand Fechner's laws, and the psychophysical contrast notion. Finally,it is shown that the LIP model is a powerful and tractable framework for handling the contrast notion. This is done througha survey of several LIP-model-based contrast estimators associated with special subparts (point, pair of points,boundary, region) of intensity images, that are justified bothfrom a physical and mathematical point of view.  相似文献   
89.
本文介绍区熔单晶硅生产操作指导专家系统。首先,系统实现了连续图象的自动变周期、定瞬间采样,并提出一种新的区域扩张增量图象处理算法.其次,叙述了知识的获取过程及类规则,提出分布的多库结构,并实现了不确定性推理.最后,开发了区熔单晶硅生产操作指导专家系统,实现了从数据和图象采集、处理、事实获取、推理到给出操作指导一体化。  相似文献   
90.
EFFECTOFSTREAMLINECURVATUREANDSOMEOTHERCONDITIONSONTHETURBULENTSTRUCTURESINTHEOTHERREGIONOFANOBSTACLELiuShi-he(WuhanUniversit...  相似文献   
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