产品三维数据模型轻量化表示实现

提出一种能快速浏览的产品三维模型轻量化文件格式,文件中包含零件显示信息和几何信息·显示信息记录面的三角化模型和边的多边形模型,以加快模型的浏览速度,且按装配、零件、面、线、点层次关系进行组织;几何数据附加在显示信息上,提供几何数据的精确查询·文件大小通过数据压缩大幅度地减小,便于在网上发布·以此为基础开发了三维产品浏览系统和用于生成轻量化文件的接口程序·     

基于移动设备的三维产品展示系统研究与实现

对如何在J2ME 平台上实现基于移动设备的三维产品信息展示系统进行了阐述,系统有效地利用 XML格式表示产品信息,并在客户端使用KXML进行解析,实现了移动设备与服务器Servlet的数据通信,实现了M3G格式的三维模型在移动设备上的展示,并提供了用户与系统的交互操作功能.在一定程度上满足了用户利用手机、PDA等移动设备,及时获得企业相关产品的信息和三维模型展示结果的实际需求.     

基于通用模型文件的城市三维景观面向对象可视化方法

三维模型文件的.Obj格式是一种通用的开放式模型格式。该文在分析OBJ模型文件结构的基础上,针对城市空间信息应用的特点,设计了一种通用的三维模型对象的类结构,利用该类建立的三维模型对象,可以直接获取OBJ文件中的几何、材质等三维实体信息。对象中的可视化成员方法利用模型数据和OpenGL图形处理技术实现对三维模型的真实感显示。三维通用模型和面向对象思想的引入,比较好地解决了城市三维景观中复杂模型的建模和可视化问题,有利于对复杂场景中大量三维模型的有效管理和组织。     

U3D文件格式及运行机制剖析

通用三维文件格式（U3D）是一种可扩展的三维数据文件格式,其目的是为了使下游的3DCAD数据重用和可视化。它主要嵌入到其它文件格式中来显示三维数据,因此在许多主流的应用程序中极为有用。详细分析了这种文件格式及其运行机制,并通过一个写U3D文件的编程实例来进一步说明文件的构造方式。最后,还探讨了这种文件格式的优点及其应用。     

Generating Semantic 3D Models of Underground Infrastructure

By combining semantic scene-graph markups with generative modeling, this framework retains semantic information late in the rendering pipeline. It can thus enhance visualization effects and interactive behavior without compromising interactive frame rates. Large geospatial databases are populated with the results of hundreds of person-years of surveying effort. Utility workers access these databases during fieldwork to help them determine asset location. Real-time rendering engines are highly advanced and optimized software toolkits that interactively display 3D information to users.To connect geospatial databases and rendering engines, we must transcode raw 2D geospatial data into 3D models suitable for standard rendering engines. Thus, transcoding isn't simply a one-to-one conversion from one format to another; we obtain 3D models from 2D information through procedural 3D modeling. Transcoding the geospatial database information's semantic attributes into visual primitives entails information loss. We must therefore find the right point in the pipeline to perform transcoding.     

Effects of display format and colour coding schemes on visual monitoring performance using spatially and temporally distributed visual displays

The present study examined factors that decreased task complexity so that a technology which temporally, rather than spatially, distributed information (i.e. RAP COM, for rapid communication) would result in performace advantages. This was accomplished by physically integrating the stimulus information into either the display format (i.e. an analog format) or into the response coding scheme (i.e. a colour coding scheme). Performance using the RAP COM display indicated a lower proportion of errors for the analog than for the digital format; however, a longer mean response time for a correct response was found for the analog than for the digital format. Two colour coding response schemes were used: (a)_a continuous scheme that comparised gradual changes between red and blue; (b) a distinctive scheme consisting of the colours cyan, green, yellow, orange, red, mauve, purple and blue. When the continuous colour coding responses scheme was used, performance using the RAP COM display, as compared with the spatial display, was no different after extended practice. The results of these experiments taken together indicate that the RAP COM display type may be a viable technology for some limited ‘real world’ environments.     

三维视频编码技术的发展与挑战

介绍了三维视频编码的核心技术。首先比较了纯视频格式和深度增强格式三维视频编码技术的发展方向及面临的挑战,其中重点分析了深度估计技术和视点合成技术的研究思路;然后概括了国际3DV/FTV标准的制定现状;最后对三维视频编码技术进行了总结和展望。     

Color coding of control room displays: the psychocartography of visual layering effects

OBJECTIVE: To evaluate which of three color coding methods (monochrome, maximally discriminable, and visual layering) used to code four types of control room display format (bars, tables, trend, mimic) was superior in two classes of task (search, compare). BACKGROUND: It has recently been shown that color coding of visual layers, as used in cartography, may be used to color code any type of information display, but this has yet to be fully evaluated. METHOD: Twenty-four people took part in a 2 (task) x 3 (coding method) x 4 (format) wholly repeated measures design. The dependent variables assessed were target location reaction time, error rates, workload, and subjective feedback. RESULTS: Overall, the visual layers coding method produced significantly faster reaction times than did the maximally discriminable and the monochrome methods for both the search and compare tasks. No significant difference in errors was observed between conditions for either task type. Significantly less perceived workload was experienced with the visual layers coding method, which was also rated more highly than the other coding methods on a 14-item visual display quality questionnaire. CONCLUSION: The visual layers coding method is superior to other color coding methods for control room displays when the method supports the user's task. APPLICATION: The visual layers color coding method has wide applicability to the design of all complex information displays utilizing color coding, from the most maplike (e.g., air traffic control) to the most abstract (e.g., abstracted ecological display).     

三维地形生成及其可视化处理研究

针对在三维地形处理领域中存在的地形数据获取困难,可视化处理过程复杂真实感效果不强的问题.文中提出了一种三维地形生成和可视化处理的方法,该方法采用分形算法生成虚拟地形数据,然后将其存储为地理信息系统中通用的数字高程数据格式,最后将数据导入三维建模软件Multigen Creator 3.0中,结合网格生成、三维投影和纹理映射等,进行可视化处理.仿真试验表明:该方法能快速获取有效的地形高程数据,经过处理后得到了直观的,真实感较强的三维显示效果图.该文为三维地形生成和可视化处理问题提供了一种有效的、可实现的处理方法.     

U3D文件在PDF中的应用及其C＋＋编程实现

在探讨PDF文件格式的基础上,提出了一种通用三维(简称U3D)文件格式嵌入到PDF文件中的方法。这种方法具有可扩展性,对于如何在其他文件中支持U3D文件格式的应用研究也具有一定的参考价值。最后,还通过C++编程实现了在PDF文件中嵌入3D作品,并允许用户交互地观看显示效果。     

3D scan for the digital preservation of a historical temple in Taiwan

This study presents the efforts in archiving Chinese architecture using a long-range 3D laser scanner. A historical architecture, the main hall of the Pao-An Temple, was preserved in a digital format with the architectural shapes retrieved more accurate than traditional manual measurements did. The difficulties in measuring as-built free forms and curves up to the size of a building were encountered and solved to enable the display of the hidden inter-relationship between outdoor and indoor profiles through sections. This research identified the most error-prone measurements done by traditional approach by comparing original drawings with the final models which registered 1958 scans and sub-scans. To represent the special characteristics of as-built 3D temple form, the study includes the application of metadata in architecture, the information management of digital data, and the Internet display of large 3D data sets.     

Video 2‐D—to—3‐D conversion based on hybrid depth cueing

Abstract— With the maturation of three‐dimensional (3‐D) technologies, display systems can provide higher visual quality to enrich the viewer experience. However, the depth information required for 3‐D displays is not available in conventional 2‐D recorded contents. Therefore, the conversion of existing 2‐D video to 3‐D video becomes an important issue for emerging 3‐D applications. This paper presents a system which automatically converts 2‐D videos to 3‐D format. The proposed system combines three major depth cues: the depth from motion, the scene depth from geometrical perspective, and the fine‐granularity depth from the relative position. The proposed system uses a block‐based method incorporating a joint bilateral filter to efficiently generate visually comfortable depth maps and to diminish the blocky artifacts. By means of the generated depth map, 2‐D videos can be readily converted into 3‐D format. Moreover, for conventional 2‐D displays, a 2‐D image/video depth perception enhancement application is also presented. With the depth‐aware adjustment of color saturation, contrast, and edge, the stereo effect of the 2‐D content can be enhanced. A user study on subjective quality shows that the proposed method has promising results on depth quality and visual comfort.     

月面探测器三维可视化方法研究

随着我国探月工程的推进,最后一阶段的任务便是在月面完成无人采样并安全返回.为了能在地面模拟出探测器在月面的实时情况,本研究使用Autodesk 3dsmax创建探测器模型后转成3DS格式的文件,并利用C++和OSG库实现对探测器的三维重构并进行可视化显示,实验结果表明：OSG库能够满足对探测器的可视化显示的需求,为未来"嫦娥五号"工程月面采样的可视化显示提供了一定的参考依据.     

Extending distortion viewing from 2D to 3D

Addresses the visual exploration of 3D information layouts. Several visual exploration techniques have been proposed for 2D information layouts. Many of these try to take advantage of humans' natural visual pattern-recognition abilities to understand global relationships while simultaneously integrating this knowledge with local details. This desire for detail-in-context views (also called fisheye, multiscale and distortion views) has fueled considerable research in the development of distortion viewing tools. Generally, these tools provide space for magnification of local detail by compressing the rest of the image. In considering a possible detail-in-context view for 3D layouts, we first examine 2D distortion techniques, bearing in mind the particular 3D problem of occlusion. Comparing 2D and 3D information layout adjustment tools leads directly to a 3D visual access tool that clears a line of sight to any region of interest. While our technique can extend to any type of 3D information display, we focus on graphs     

浅析三维图形中的信息隐藏技术

目前对三维图形作品的知识产权的保护与重要信息加密隐藏的需求日益增长,人们开始使用隐藏技术为三维数字化作品添加数字水印或通过三维图形信息隐藏技术加密重要信息.文章对三维图形中的信息隐藏技术作了剖析,并对基于距不变特征的隐藏算法进行了研究,最后利用ply格式的三角形网格Cow三维模型对算法进行了验证.     

一种城市三维建模的集成处理方法

在对AutoCAD和MapInfo的数据结构进行分析比较的基础上，首先提出了从CAD图形符合及注记中，提高取程点、高程值以及相关属性信息的面积匹配与类型转换的方法；然后创建了基于CAD线划建筑物的重现点-线拓扑关系生成多边形的方法；最后实现了地形高程与建筑物空间及其属性特征值的自动获取，在此基础上进一步构建了城市DEM模型和实现了三维影象显示，形成了由CAD数据→GIS矢量数据→GIS栅格数据→三维影像的一种城市三维建模的集成处理方法，该方法较之工程化的航空摄影测量方法简单、快速、具有较大的实有价值，另外，还以苏州市32 号街坊的地形数据为例进行了实验，获得了较好的实验结果。     

基于GeoFusion的三维地形和目标模型调度显示研究

针对大型场景的实时绘制问题,提出了一种基于GeoFusion的三维可视化技术.首先分析了GeoFusion三维视景平台的基本情况及对用户应用程序的支持,详细阐述了三维地形数据的坐标转换、格式转换和生产制作处理流程,结合GeoMatrix给出了地形调度显示方法,建立了DSM三维目标模型,提出了三维目标模型的调度算法.开发了仿真系统,并通过实例表明了所提地形和目标模型创建及调度显示算法能够实现实时调度和场景的实时显示,并保证了场景的真实感.     

三维虚拟维护训练系统关键技术研究

针对三维虚拟维护训练中设备拆装操作复杂的问题,提出一种通用的拆装关系数 据格式和处理方法,可方便定制各种设备的拆装训练应用;提出一种高效简洁的自动轴对齐约 束拆装操作方法,并以此设计实现了一种二维屏幕空间的移动拖拽器。通过OSG 引擎进行场景 渲染和管理,分析了系统的体系结构和场景组织设计,开发了一套虚拟拆装训练三维仿真系统, 实现了拆装操作记录的统计和报表输出。应用结果表明,该系统具有较好的实时性和显示效果。     

态势可视化的二三维联动技术

研究了主流的二维和三维显示技术,WGS84坐标和墨卡托投影坐标变换方法,消息中间件和AAR存档系统等态势可视化技术,提出了数据库API网关.设计并实现了一种二三维联动的态势可视化系统,采用消息中间件同步仿真过程信息,用数据库API网关统一管理实体的二三维模型,用AAR存档系统记录和回放仿真过程,经测试,态势可视化系统能够正确的,有效的完成仿真功能,且二维和三维显示部分显示的态势是联动的.     

Bare finger 3D air‐touch system with embedded multiwavelength optical sensor arrays for mobile 3D displays

A camera‐free 3D air‐touch system was proposed. Hovering, air swiping, and 3D gestures for further interaction with the floated 3D images on the mobile display were demonstrated. By embedding multiwavelength optical sensors into the display pixels and adding angular‐scanning illuminators with multiwavelength on the edge of the display, the flat panel can sense images reflected by a bare finger from different heights. In addition, three axis (x, y, z) information of the reflected image of the fingertip can be calculated. Finally, the proposed 3D air‐touch system was successfully demonstrated on a 4‐inch mobile 3D display.