Information availability in 2D and 3D displays

Why are 3D displays good for rapidly appreciating the third dimension of scenes? We show that information availability is more important than the 3D display format. Participants engaged in visual search for the attributes of altitude and pitch for coding schemes. This design let us disentangle the display format and information coding scheme so that we could properly evaluate the effect of each on performance     

Stereoscopic 3D displays and human performance: A comprehensive review

To answer the question: “what is 3D good for?” we reviewed the body of literature concerning the performance implications of stereoscopic 3D (S3D) displays versus non-stereo (2D or monoscopic) displays. We summarized results of over 160 publications describing over 180 experiments spanning 51 years of research in various fields including human factors psychology/engineering, human–computer interaction, vision science, visualization, and medicine. Publications were included if they described at least one task with a performance-based experimental evaluation of an S3D display versus a non-stereo display under comparable viewing conditions. We classified each study according to the experimental task(s) of primary interest: (a) judgments of positions and/or distances; (b) finding, identifying, or classifying objects; (c) spatial manipulations of real or virtual objects; (d) navigation; (e) spatial understanding, memory, or recall and (f) learning, training, or planning. We found that S3D display viewing improved performance over traditional non-stereo (2D) displays in 60% of the reported experiments. In 15% of the experiments, S3D either showed a marginal benefit or the results were mixed or unclear. In 25% of experiments, S3D displays offered no benefit over non-stereo 2D viewing (and in some rare cases, harmed performance). From this review, stereoscopic 3D displays were found to be most useful for tasks involving the manipulation of objects and for finding/identifying/classifying objects or imagery. We examine instances where S3D did not support superior task performance. We discuss the implications of our findings with regard to various fields of research concerning stereoscopic displays within the context of the investigated tasks.     

The use of 2D and 3D displays for shape-understanding versus relative-position tasks

Research on when and how to use three-dimensional (3D) perspective views on flat screens for operational tasks such as air traffic control is complex. We propose a functional distinction between tasks: those that require shape understanding versus those that require precise judgments of relative position. The distortions inherent in 3D displays hamper judging relative positions, whereas the integration of dimensions in 3D displays facilitates shape understanding. We confirmed these hypotheses with two initial experiments involving simple block shapes. The shape-understanding tasks were identification or mental rotation. The relative-position tasks were locating shadows and determining directions and distances between objects. We then extended the results to four experiments involving complex natural terrain. We compare our distinction with the integral/separable task distinction of Haskel and Wickens (1993). Applications for this research include displays for air traffic control, geoplots for military command and control, and potentially, any display of 3D information.     

The effect of 2D and 3D visual modes on surgical task performance: role of expertise and adaptation processes

The aim of this paper is to analyze how novices and experts are able to safely adapt and transfer their skills to new technology in medical domain. In order to answer this question, we compared the performance of 12 novices (medical students) with the performance of 12 laparoscopic surgeons (using a 2D view) and 4 robotic surgeons, using a new robotic system that allows 2D and 3D view. Our results showed a trivial effect of expertise (surgeons generally performed better than novices). Moreover, they revealed that experts have adaptive transfer capacities and are able to transfer their skills independently of the human–machine system. However, even if we observe transfer of skills, we showed that expert’s performance may be disturbed by changes in their usual environment. In a safety perspective but also for novice and expert training, this study emphasizes the necessity to take into account the impact of these environmental changes and the expert’s adaptive capacities but also the limits of expert’s adaptive capacities.     

脑皮层的立体脑回图展成平面的新方法

用核磁共振 (MRI)大脑断层图 ,分析患者的脑皮层解剖特征是一项困难的工作 .一个可能的途径是将分割后的脑皮层进行三维重建 .但是重建后的三维立体脑皮层图 ,如不经过 36 0°旋转仅能看到脑皮层上脑回的一部分 .因此还需要展开成平面脑回图以看到脑回的完整走向 .文中提出的投影方法能够在变形尽量小的前提下将立体脑回图展开在平面上 ,直观地看到脑回走向的全貌 ,便于临床诊断或治疗中应用     

Effects of 3D displays: A comparison between shuttered and polarized displays

The current study investigates the effects of 3D displays (shuttered display vs. polarized display). People experienced superior fidelity and brightness when they watched 2D still images on a shuttered display, rather than on a polarized display. Conversely, people experienced greater brightness when they watched 3D still images on a polarized display, rather than on a shuttered display. Second, people were able to read a smaller font or characters on a shuttered display than on a polarized display. Third, people noticed flickering on a shuttered display when they watched 3D images. Fourth, people experienced greater brightness when they watched 3D moving images on a shuttered display, rather than on a shuttered display. The perceived brightness of the screen positively correlated with enjoyment, content satisfaction, and 3DTV satisfaction when the viewers watched a 3D movie. The flickering, on the other hand, has a negative correlation with enjoyment and 3DTV satisfaction.     

三维地形的可视化技术与实现

本文介绍了基于VC 6.0和OpenGL图形标准模拟真实感三维地形的技术方法,阐述了OpenGL的工作原理和三维地形动态模型的建立过程及其应用.     

Visualization of 3D ultrasound data

It is suggested that ultrasound data acquisition will play an increasing role in the future of medical imaging. Unlike magnetic resonance imaging (MRI) and computerized tomography (CT), ultrasound offers interactive visualization of underlying anatomy in real time. Additionally, ultrasound equipment costs far less and does not use ionizing radiation or require specialized facilities. The different methods for multidimensional medical imaging and scientific visualization are reviewed. Several volume visualization algorithms are discussed. They are multiplexer slicing, surface fitting, volume rendering, data classification, and viewing and shading. Three-dimensional ultrasound data display methods are also discussed     

Visualization Blackboard-visualizing 3D PET images

Characteristics of positron emission tomography (PET) images that limit human ability to accurately perceive the information the images contain are discussed. They are relatively low spatial resolution, a lack of apparent anatomical information and the expression of metabolic activity in terms of brightness levels (gray levels), which are not efficiently determined by the human visual system. These affect how clearly the 3-D structures contained in the reconstructed 3-D images can be seen. The use of pseudocolor to visualize different levels of activity expressed by brightness and shading to accentuate depth and shape information is described. To further enhance the brightness contrast of a surface with its neighboring areas, stereo and motion were used as depth cues     

基于纹理的增强型3D流场绘制

提出一种基于纹理的增强型3D矢量场可视化算法,可显著地改善传统纹理法的绘制质量.首先通过对3D纹理的线性卷积运算生成具有空间相关性的卷积纹理;然后对卷积纹理进行高通滤波,以增加流面内流线之间强度的对比;最后通过体绘制方式展示3D卷积纹理.借助权重区域,该算法可以显示用户感兴趣区域或特征区域,避免卷积数据过多引起的紊乱及相互遮挡.     

Evaluating graphics displays for complex 3D models

This article summarizes a user study of viewing 3D geometry on large-screen display devices. The geometry models the structure of a complex physical object. Our results show that the crispness of a display device (intraframe performance) must be considered along with the speed at which new frames can be computed (interframe performance). It's important to consider crispness from the user's perspective, using values that aren't often published in device specifications. Equally important is the framework for different types of 3D data and the categorization of display technology and techniques     

1D selection of 2D objects in head-worn displays

In current desktop user interfaces, selection is usually accomplished easily with a mouse or a similar two-dimensional locator. In wearable computing, however, controlling two dimensions simultaneously gets significantly harder: a change in one dimension results easily in an undesired change in the other dimension as well when the user is occupied with a parallel task – such as walking. We present a way to overcome this problem by applying one-dimensional selection for graphical user interfaces in head-worn displays. Our new interaction technique allows a wearable computer user to perform object selection tasks easily and accurately. The technique is based on a visible circle on the screen. The user controls the circle, altering its radius with a one-dimensional valuator. The midpoint of the circle is in the middle of the screen. The object currently on the perimeter of the circle is highlighted and can be selected. Our preliminary usability evaluation, applying our custom evaluation method designed especially for walking users, indicates that the proposed technique is usable also when walking.     

Java 3D可视化技术及其应用

Java3D是Java语言在三维领域的扩展,本文较为详细地阐述采用Java3D语言对三维实体进行可视化显示的方法及具体实施,并着重分析了三维实体的颜色处理及灯光效应,通过实例说明多种三维实体表面着色的方法及效果。程序既可以是应用程序也可以在互联网上运行,展示出来的结果是交互的,可以改变观测角度及任意缩放、平移。本文具体说明了该方法的实施过程。本文的方法可以应用于多种领域,比如计算机远程教学、三维立体模型显示及科学计算的可视化等。     

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.     

地形三维可视化的实现与应用

文中讨论了地形三维可视化的原理,详细介绍了高级编程语言与OpenGL结合开发环境下的地形三维可视化的计算机实现过程。在此基础之上,讨论了基于GRID DEM的应用分析功能的实现,包括等高线、坡度图、通视分析以及淹没分析。为三维地形可视化的实施提出了有效的方案。     

GeoBuilder: A Geometric Algorithm Visualization and Debugging System for 2D and 3D Geometric Computing

Algorithm visualization is a unique research topic that integrates engineering skills such as computer graphics, system programming, database management, computer networks, etc., to facilitate algorithmic researchers in testing their ideas, demonstrating new findings, and teaching algorithm design in the classroom. Within the broad applications of algorithm visualization, there still remain performance issues that deserve further research, e.g., system portability, collaboration capability, and animation effect in 3D environments. Using modern technologies of Java programming, we develop an algorithm visualization and debugging system, dubbed GeoBuilder, for geometric computing. The GeoBuilder system features Java's promising portability, engagement of collaboration in algorithm development, and automatic camera positioning for tracking 3D geometric objects. In this paper, we describe the design of the GeoBuilder system and demonstrate its applications.     

基于VTK的医学图像可视化三维重建

医学三维数据场可视化是当前科学计算可视化应用的重点,具有重要的学术意义和应用价值.体绘制是该技术的一个主要的方法.在VTK(Visualization Toolkit)类库提供可视化与显示功能的基础上,主要讨论了光线投射算法进行体数据的绘制的特点,同时采用了包围盒技术改善了光线投射算法的绘制速度.实验结果表明,图像的质量在没有受到影响的前提下,图像的绘制速度得到了大幅度的提高,同时证明了VTK是医学三维数据场可视化的有力工具.     

医学体数据三维可视化技术

医学体数据的可视化是科学计算可视化的重要研究领域,其处理过程包括体数据的获取、模型的建立、数据的映射、绘制等操作。论文对医学体数据可视化的相关技术进行了综述,讨论了医学体数据的结构模型和表示方法,全面地分析了医学体数据可视化中各种算法和技术的特点,及相关的加速技术,探讨了目前医学体数据可视化存在的问题及发展趋势。