共查询到20条相似文献,搜索用时 156 毫秒
1.
一种无标记点三维点云自动拼接技术 总被引:1,自引:0,他引:1
基于相位投影和双目的三维光学测量系统已经广泛应用于各领域.受投影光测量系统单次测量范围大小的限制,对大型物体的测量需要在表面粘贴圆形标记点进行多次拼接的缺点,探讨一种基于SIFT的无标记点自动拼接技术.该技术采用SIFT方法获取两次测量的特征点,其次结合RANSAC求出图像特征点的匹配关系,再根据立体匹配中图像特征点与三维点云之间的对应关系,将二维特征点的对应关系映射到三维点云的对应关系上,最后由SVD奇异值分解算法求得旋转和平移矩阵实现拼接.实验证明:该方法可以避免在被测量对象上粘贴标记点,能够快速准确地实现自动拼接. 相似文献
2.
基于全景图像的三维全景漫游系统的构建 总被引:2,自引:0,他引:2
三维全景漫游系统以全景图的方式再现了三维场景,在浏览器上可以实现虚拟场景的漫游,具有很好的交互性和真实感。论文以海南数字生态旅游三维全景漫游系统的构建为目标,研究了利用鱼眼镜头和单电数码相机进行全景图像获取方法,以及对全景图像进行再次拼接制作360°全景图漫游系统。该系统构建方法为三维全景技术的应用提供了一个参考。 相似文献
3.
基于公共特征点的三维测量数据拼接方法 总被引:1,自引:0,他引:1
针对大型物体和回转体的三维形貌视觉测量,提出了一种基于公共特征点的三维数据拼接方法.该方法首先把测量对象的表面划分成若干个子区域,并且确保相邻的子区域含有重合区域,然后采用一套双目立体视觉测量系统对各个子区域进行单独测量,利用重合区域的公共特征点计算前后两次测量的空间变换矩阵,将三维点坐标转换到一个坐标系下完成拼接.变换矩阵的计算引入了Rodrigues参数,简化了运算过程,且具有较高的精度.该方法操作简单,非常适合于实际应用,实验结果证明了此方法的有效性. 相似文献
4.
针对传统二维测量系统存在测量精度较低、稳定性差的不足,提出一种基于数据交互的三维虚拟动态测量方法;该方法采用三维构型与总线技术同步耦合的工作方式,对三维测量系统中模型驱动的关键问题进行了研究,探讨了三维测量系统中数据交互解决方法的可行性,并将该方法应用于煤矿排水系统,完成了三维虚拟动态测量系统的开发;试验结果表明由该方法实现的三维虚拟动态测量系统具有运行稳定、操作简单、直观性强、可靠性高的优点,应用前景广阔。 相似文献
5.
随着国内机械制造行业水平的快速提升,国产坐标测量仪器也得到了迅猛的发展,但国内缺少类似Spatial Analyzer,PolyWorks和PC-DIMIS这样的通用型三维坐标测量软件.三维坐标测量软件一般以尺寸测量和形位误差评价功能为主,其核心功能是解析CAD模型的数据、对测量数据进行处理.三维引擎AnyCAD是一款集三维显示平台和造型平台于一身的三维开发组件.对AnyCAD在坐标测量软件开发中的应用进行研究,利用AnyGeom模块实现对CAD模型数据的解析,利用AnyViz模块实现了三维模型和测量数据可视化,最终开发出一款具有良好人机交互功能的通用型三维坐标测量软件.研究表明,AnyCAD引擎可以满足坐标测量软件开发的基本需求,能够实现坐标测量软件的快速搭建;该坐标测量软件具有完全自主知识产权,具备对进口设备和国产设备的多重兼容性. 相似文献
6.
利用结构光进行三维测量或场景再现是图像处理领域的重要应用,结构光的编码与构造是进行以上工作的基础。文章首先讨论了建立三维测量系统的方法,然后重点介绍了光栅投影相位法实现三维测量的原理与应用方式。通过该方法,实现对较大表面物体的测量与三维重构。 相似文献
7.
本文阐述了位相轮廓的测量原理,在此基础上,对三维面形测量系统进行了设计,给出了测量结果,并对结果进行了讨论。 相似文献
8.
显微三维测量系统是将四步相移结合编码技术和三维传感技术相结合,应用于光学立体显微镜上,可对一些微小物体进行观测和测量,并获取深度信息,建立三维图像,从而用简便、经济的手段进行微小物体的三维测量。本文简要的介绍了该原理及系统的组成,并列举目前在一些领域中的应用实例。 相似文献
9.
10.
11.
三维物体识别及姿态测定的推理系统 总被引:1,自引:1,他引:0
本文介绍了三维物体识别及姿态测定的一种新技术,从物体空间域模型出发,通过约束推理及几何推理,在物体三维信息部分给定的条件下,推断预测图象模型,并通过实测的图象数据反馈,推断出隐含在图象中未给定的三维信息,最终实现三维物体识别及姿态测定。整个系统在VICOM机上用C语言完成。 相似文献
12.
Most face recognition systems employ 2-D color or gray-scale images. However, face recognition based on 2-D images is adversely
affected by 3-D movement, variable lighting, and the use of cosmetics. 3-D image measurement technology has the potential
to overcome these limitations of face recognition based on 2-D images since it can perform geometric analysis. We propose
a method that is capable of recognizing a person from a 3-D facial image obtained using a 3-D shape measurement system by
employing a technique that optimizes the intensity-modulation pattern projection. This face recognition method is based on
the iterative closest point algorithm. It is robust to changes in reflectivity and color. Since the 3-D facial information
can be registered, this method can estimate rotations and translations to compensate for different positions or directions.
In order to prove the validity of the proposed technique, a verification experiment was conducted which used 105 sample 3-D
images obtained from 15 subjects. It achieved a detection rate of 96% when heads were turned at an angle of 20° or less relative
to the camera. 相似文献
13.
A traditional approach to extracting geometric information from a large scene is to compute multiple 3-D depth maps from stereo pairs or direct range finders, and then to merge the 3-D data. However, the resulting merged depth maps may be subject to merging errors if the relative poses between depth maps are not known exactly. In addition, the 3-D data may also have to be resampled before merging, which adds additional complexity and potential sources of errors.This paper provides a means of directly extracting 3-D data covering a very wide field of view, thus by-passing the need for numerous depth map merging. In our work, cylindrical images are first composited from sequences of images taken while the camera is rotated 360° about a vertical axis. By taking such image panoramas at different camera locations, we can recover 3-D data of the scene using a set of simple techniques: feature tracking, an 8-point structure from motion algorithm, and multibaseline stereo. We also investigate the effect of median filtering on the recovered 3-D point distributions, and show the results of our approach applied to both synthetic and real scenes. 相似文献
14.
15.
16.
Hu G. Stockman G. 《IEEE transactions on pattern analysis and machine intelligence》1989,11(4):390-402
A method for 3-D surface measurement using a projected grid of light is presented. The grid line identification problem is solved using very general constraints. At the same time, 3-D surface patch solutions are developed. From the general constraints of set of geometric and topological rules are derived that are effectively applied in the computation of grid labels and hence 3-D surface solutions. A set of five algorithms has been applied on five real scenes consisting of multiple objects of arbitrary shapes. The results show that globally consistent surface solutions can be obtained rapidly with good accuracy using a single image. A small degree of ambiguity remains, but can be further reduced or removed using increased knowledge 相似文献
17.
Exploratory retail studies in South Africa indicate that plus-sized women experience problems and dissatisfaction with poorly fitting bras. The lack of 3-D anthropometric studies for the plus-size women's bra market initiated this research. 3-D body torso measurements were collected from a convenience sample of 176 plus-sized women in South Africa. 3-D breast measurements extracted from the TC(2) NX12-3-D body scanner 'breast module' software were compared with traditional tape measurements. Regression equations show that the two methods of measurement were highly correlated although, on average, the bra cup size determining factor 'bust minus underbust' obtained from the 3-D method is approximately 11% smaller than that of the manual method. It was concluded that the total bust volume correlated with the quadrant volume (r = 0.81), cup length, bust length and bust prominence, should be selected as the overall measure of bust size and not the traditional bust girth and the underbust measurement. STATEMENT OF RELEVANCE: This study contributes new data and adds to the knowledge base of anthropometry and consumer ergonomics on bra fit and support, published in this, the Ergonomics Journal, by Chen et al. (2010) on bra fit and White et al. (2009) on breast support during overground running. 相似文献
18.
三维虚拟服装缝合技术研究 总被引:10,自引:1,他引:10
讨论三维计算机辅助服装设计系统中二维衣片转换为三维服装的有关技术问题。针对实现三维场景中服装的缝制及再现服装穿着的真实效果进行了深入研究。对于二维服装衣片的离散问题,提出基于正则栅格法思想的四边域网格剖分算法,界定了对位缝合和褶皱缝合的新概念,通过相应的边界调整方案解决了复杂服装的缝制问题;在缝合模拟过程中,分析衣片缝合前后缝合力的作用,并给出不同阶段的约束处理方法;最后针对服装同人模之间的碰撞,提出一个基于层次剖分法、融合包围盒检测技术特点有碰撞检测加速算法。这些技术均在三维虚拟服装缝制模拟系统中得以验证。 相似文献
19.
Robert B. Collender 《Displays》1987,8(4):193-209
Approaches are described for image acquisition and playback for 3-D computer graphics, 3-D television and 3-D theatre movies without special glasses. Projection lamps, spatial light modulators, CRTs and dynamic scanning are all eliminated by the application of an active image array, all static components and a semispecular screen. The resulting picture shows horizontal parallax with a wide horizontal view field (up to 360°), giving a holographic appearance in full colour with smooth, continuous viewing without speckle. Static component systems are compared with dynamic component systems using both linear and circular arrays. Computer graphic systems are shown, which allow complex shaded colour images to extend from the viewer's eyes to infinity. Large screen systems visible by hundreds of people are feasible by the use of low f-stops and high-gain screens in projecttion. Screen geometries and special screen properties are shown. 相似文献
20.
鲁棒水印技术通常被用于版权保护和所有权声明等目的。许多提出的水印方案通常把水印嵌入在变换域内,如2维的DFT域、DCT域和DWT域以及3维的DCT域、WT域。前3个域主要被用于2维的图像载体,而后2个域主要被用于3维的视频载体和3维的图像载体。在本文中,一种基于3维提升可分离小波(3-D SWT)的灰度图像水印方案被提出。首先,通过之字扫描把灰度图像分解为3维的图像序列,然后使用3-D SWT变换这些图像序列。同时通过相对熵理论证明了3-D SWT变换系数符合广义高斯分布。为了平衡鲁棒性和不可感知性,新的适用于3维的人类视觉模型被重构并用于调整水印的嵌入强度。在水印的检测方面,最优检测器实现水印的盲检测。实验表明本方案对各种攻击是强鲁棒的。 相似文献