intGuide: A platform for context-aware services featuring augmented-reality, based on the outcome of European Research Projects

As people become increasingly acquainted with information technology, they demand continuous availability of services related to their work or leisure. The era of ubiquitous computing announced long ago is currently turning into an everyday reality at an ever-increasing pace. Alongside the evolution of ubiquitous and nomadic computing, the need of people to access vast amounts of information in a comprehensive and efficient way gives rise to the areas of information visualization and augmented-reality. Such technologies allow for the comprehensive presentation of visual information equally addressing the needs of different categories of people.

In the past 5 years, we have been active in a set of European Research Projects addressing the above-mentioned research directions, with the long-term goal to develop a software platform that will enable context-aware services deploying advanced visualization technology in a series of application domains, such as cultural heritage dissemination, interactive television and retail industry. The multitude of the application domains addressed, as well as the multidisciplinary expertise necessary to create a generic platform was successfully addressed in complementary research activities. In this paper, we present the idea of a platform for context-aware services by exploiting advanced visualization technology and subsequently we briefly review the research projects that delivered valuable pieces in the overall puzzle. Emphasis is put on the practical issues of the implementation and deployment in different application scenarios.     

我国军用夜视仪器可靠性分析研究

军用夜视仪器是高新技术装备，要求有好的可靠性做保证。通过对军用夜视仪器的可靠性现状分析，结合国外的先进经验，介绍了可靠性的研究方法。     

Calibrating camera radial distortion with cross-ratio invariability

The calibration of camera distortion plays an important role in the field of industrial machine vision application. In this paper, a novel approach for calibrating camera radial distortion is presented based on cross-ratio invariability for perspective projection. Assumed to be with one-order radial distortion, the image coordinates and the cross-ratio of only four collinear points in space are needed in this approach. The cross-ratio, easily known from a calibration target, is identical with that of the four corresponding image points. This is called the cross-ratio invariability for perspective projection. A monadic two-order equation is built based on the cross-ratio invariability, which gives an accurate solution to radial distortion coefficients. A digital simulation and a practical image correction prove this approach to be simple, accurate, efficient and time saving.     

玻璃微光管及其应用

简述了玻璃微光管的结构和性能特点，并介绍了利用玻璃微光管开发微光夜视仪应注意的一些问题。由于玻璃微光管的价格相对低廉，其在民用和准军用方面的应用还大有可为。     

空间球形物体自动定位方法研究

利用双目立体视觉技术对空间物体进行定位的一个难点在于特征点的选择和匹配，常用的方法是选择一幅图像中物体的形心为特征点，然后根据灰度或者颜色值在另外一幅中进行匹配。为了达到较好的精度，所用的匹配算法都比较复杂，并且当物体表面颜色分布均匀时错误匹配率较高。针对球形物体，本文提出基于形心几何匹配的定位方法，避开了常规匹配方法所面对的难题，经过试验验证，效果很好。     

SNR analysis of the stripe illuminator based on linear emitter and cylindrical lens against solar irradiance

Achieving good signal-to-noise ratio (SNR) against solar illumination is a basic requirement for the light source of active vision sensors in outdoor applications. The article examines the high power stripe-lighting setup, constructed with a cylindrical lens and a rectangular emitting source placed at the focal line of the lens. This source type is capable of illuminating a very high total power because of the large surface size of the emitter; thus it is advantageous for outdoor applications. A detailed radiometric analysis of this setup is presented resulting in an integral for the calculation of the spatial irradiance distribution within the stripe. The achievable SNRs against solar illumination are calculated by applying the radiometric integral for different rectangular emitters built of LED arrays, laser diode arrays and incandescent sources. The article proposes stripe illuminators applying all the analyzed emitter types that are suitable for operation in direct sunshine.     

Vision system for three-dimensional position measurement based on stereo disparity

A stereo disparity-based range finding technique was developed for measuring three-dimensional coordinates of object points. It used an image-matching algorithm which functionally consisted of scene reduction, epipolar line selection, and features matching. Experiments implementing this technique were performed on an industrial vision system. An error analysis indicated that image resolution was the major source of measurement inaccuracy.     

脉冲He—Ne激光用于斜弱视治疗

本文介绍了脉冲He-Ne激光治疗儿童斜弱视的光电原理、治疗方法与临床应用。     

基于双目视觉模型的运动参数测量

通过建立双目测量的数学模型,由标志点在双摄像机成像平面上的坐标求得运动物体的运动参数。在不考虑摄像机内外参数标定误差的情况下,研究了标志点像元的测量精度对运动参数测量的影响。通过分析图像分割求取标志点形心引起的误差,利用窗口中心迭代算法提高标志点形心测量的精度,从而提高了运动参数的测量精度。由空间飞行器自动交会的仿真试验验证了算法的有效性。     

3-D imaging and modeling – Part I: acquisition and registration

The key modules in a typical reverse engineering system consist of the acquisition, registration, and the integration of range images of three-dimensional objects with complex geometry. We first present a self-made optical digitizer that is employed for quickly acquiring range data from multiple views, then introduce a visualized registration procedure that can provide a reliable estimate for the fine registration of multiple range images in a unified coordinate system. Experiment results are given to show the effectiveness of this approach in 3-D imaging and multiple range image registration for the applications of reverse engineering.