水下成像的现状和发展动向

本文以下水成像在军事，海洋开发工程应用为基础，论述了水下观测和成像中采用微光电视摄像机和激光器件及其系统的技术现状和发展动向。     

基于无人机倾斜摄影的嘉兴老城区住宅识别

为了应对老城区房屋数据信息不足、获取不便的问题,提出利用无人机（UAV）倾斜摄影测量技术实现老城区住宅自动识别的方法. 根据老城区典型多层住宅的外立面特征,确定出阳台构造、立面朝向和房屋长宽比3个参数控制的住宅判别标准. 通过无人机摄影测量获取嘉兴研究区的密集匹配点云、数字正射影像（DOM）和数字表面模型（DSM）数据. 融合DOM及DSM数据提取单体建筑轮廓,分割出单体房屋点云. 基于RANSAC算法提取房屋立面点云并确定立面朝向,根据立面的点云空间分布判断立面长度及阳台构造. 试验表明,在研究区应用该方法识别典型住宅的准确率可以达到90%.     

JX4ADPS在数字近景摄影测量中的应用

阐述了全数字摄影测量工作站在近景摄影测量中的应用,对JX4ADPS获取某隧道洞口测量项目中数字成果的技术经验进行探讨.     

Comparison of three-dimensional surface scanning techniques for capturing the external ear

Congenital facial anomalies, such as microtia (malformation of the external ear), lead to significant psychosocial effects starting from early childhood. Three-dimensional (3D) scanning and advanced manufacturing are being investigated as a cheaper and more personalised method of fabricating reconstructive treatments for patients compared to traditional approaches. To date, most case studies have used expensive 3D scanners, yet, there is potential for low-cost devices to provide comparable results. This study aimed to investigate these different approaches. Both ears of 16 adult participants were scanned with three devices: Artec Spider (Artec Group), Intel^® RealSense? (Intel), and the Apple iPhone^® 7 (Apple Inc.) combined with photogrammetry using 90, 60 and 30 photographs. The scanning time, processing time, accuracy, completeness, resolution and repeatability of each technique were assessed using the Artec Spider as a reference scanner. Our results show that the iPhone had the longest processing time however, this decreased nine-fold when reducing the number of photos from 90 to 30. There was no significant difference in the accuracy, completeness or repeatability of the iPhone scans with 90 photographs (1.4?±?0.6?mm, 79.9%, 1.0?±?0.1?mm), 60 photographs (1.2?±?0.2, 79.3%, 0.9?±?0.2?mm) or 30 photographs (1.2?±?0.3?mm, 74.3%, 1.0?±?0.2?mm). The Intel RealSesne performed significantly worse in each parameter (1.8?±?03?mm; 46.6%, 1.4?±?0.5). Additionally, the RealSense had significantly lower resolution with not enough detail captured for the application. These results demonstrate that the ear can be accurately 3D scanned using iPhone photographs. We would recommend capturing between 30 and 60 photographs of the ear to create a scan that is accurate but without the downfall of long processing time. Using these methods we aim to provide a more comfortable setting for the patient and a lower-cost and more personalised ear prosthesis.     

无人机遥感平台技术研究与应用

作为一种新型的遥感平台,UAS(无人飞行器系统)具有优于其它遥感平台的灵活性、实时性、移动性等特点,本文介绍了UAS的发展现状及其关键技术,提出了UAS遥感平台的分类方法,从技术、市场、法律制度、成本等多方面考察了UAS应用于民用遥感领域的可行性。理论和实践证明,UAS平台在遥感技术的发展中必将发挥重要的作用,成为主流的遥感平台之一。     

钢筋拉伸实时摄影测量方法的研究

针对传统拉伸试验机存在的不能测量局部形变、精度不高、自动化程度低等问题,研究了在传统试验机上进行摄影测量系统改造的方法,提出了一种标记点提取的可靠算法,及用于一维尺寸测量的系统标定的简易方法,并开发了相应的软件系统。实验证明,在设备制造成本不明显增加的情况下,实现了钢筋局部变形的实时测量,提高了测量精度,且系统便于操作维护,运行稳定可靠。     

基于近景数字摄影的坐标精密测量关键技术研究

研究了基于数字近景摄影原理的三维坐标精密视觉测量方法，可用于工业现场大尺寸范围内的坐标测量。对其核心技术，即数字成像器件高精度模型及标定、成像器件空间精密定向、高精度亚像素图像处理算法以及光学编码与精密测头技术，进行了深入的讨论，给出了原理和实现思路，为工业现场数字近景摄影三维坐标精密测量系统的设计提供了理论依据。     

Calibrated,Registered Images of an Extended Urban Area

We describe a dataset of several thousand calibrated, time-stamped, geo-referenced, high dynamic range color images, acquired under uncontrolled, variable illumination conditions in an outdoor region spanning several hundred meters. The image data is grouped into several regions which have little mutual inter-visibility. For each group, the calibration data is globally consistent on average to roughly five centimeters and 0 1°, or about four pixels of epipolar registration. All image, feature and calibration data is available for interactive inspection and downloading at http://city.lcs.mit.edu/data.Calibrated imagery is of fundamental interest in a variety of applications. We have made this data available in the belief that researchers in computer graphics, computer vision, photogrammetry and digital cartography will find it of value as a test set for their own image registration algorithms, as a calibrated image set for applications such as image-based rendering, metric 3D reconstruction, and appearance recovery, and as input for existing GIS applications.     

一种用面阵CCD测试弹丸炸点空间三维坐标的方法

文中针对靶场测试的实际要求，应用摄像测量技术，提出了用面阵CCD摄像测试弹丸炸点相对目标空间三维坐标的一种新方法。阐述了面阵CCD摄像测量炸点坐标的工作原理以及图像处理的步骤。并对其测试精度进行了分析。该方法的有效测试视场完全能够覆盖合格引信所引爆弹丸的爆炸区域，并在很大程度上提高了测试的精度。经过在靶场的实际测试，均取得了较好的实验成果。     

Methodology of improvement of radiometric quality of images acquired from low altitudes

Low-altitude photogrammetry studies have been more and more popular in the mapping of small areas (up to 10 thousand hectares). UAV flights can be consider as an attractive low-cost alternative solution for the photogrammetric studies. However, in this type of platforms images are frequently captured by digital compact cameras. Despite high resolution, the images taken with these cameras have a relatively low radiometric quality. While photogrammetric software for processing images obtained via sensors mounted on UAVs and the possible applications of the GPS RTK system for determining projection centres are constantly developing, the majority of studies nowadays still require digital aerial triangulation based on transferring and measuring tie points on subsequent images of the same surface fragment. A method for improving the quality of low-altitude image data is presented in this article. In order to improve the image radiometry, filtration in frequency domain was applied. This solution made it possible to enhance the reflection from objects in the images and at the same time reduce the impact of poor lighting on local contrast. The proposed method comprises two variants of radiometric correction, each of these depending on the quality of the pictures. The effectiveness of the method has been proven by adjusting three image blocks with different levels of radiometric quality before and after filtration, as well as a comparative analysis of the aerial triangulation results.