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141.
双目立体视觉传感器的现场标定技术 总被引:2,自引:0,他引:2
双目立体视觉传感器在机器视觉和三维测量中有着广泛的应用。其中测量精度是一个很重要的因素,尤其是在三维测量中,高测量精度的要求使得传感器的标定显得尤为重要。该文提出了一种双目立体视觉传感器的现场标定方法,不仅提高了标定精度,还避免了离线标定中大量的重复性劳动,同时也研究了摄像机镜头畸变的问题。实验结果表明,此方法能够得到满意的标定精度。 相似文献
142.
Sang-Cheol Park Author Vitae Author Vitae Seong-Whan Lee Author Vitae 《Pattern recognition》2004,37(4):767-779
In this paper, we propose a new method for estimating camera motion parameters based on optical flow models. Camera motion parameters are generated using linear combinations of optical flow models. The proposed method first creates these optical flow models, and then linear decompositions are performed on the input optical flows calculated from adjacent images in the video sequence, which are used to estimate the coefficients of each optical flow model. These coefficients are then applied to the parameters used to create each optical flow model, and the camera motion parameters implied in the adjacent images can be estimated through a linear composition of the weighted parameters.We demonstrated that the proposed method estimates the camera motion parameters accurately and at a low computational cost as well as robust to noise residing in the video sequence being analyzed. 相似文献
143.
This application describes the use of LC/Ion Trap MS and LC/TOF for the identification of and quantization of terbutylazine in olive oil samples. The analysis by ion trap was achieved in MS/MS mode, monitoring the characteristic fragment ion at m/z 174. The identification by LC/TOF was accomplishment with accurate mass, along with the accurate mass of chlorine isotope cluster present in terbutylazine. The accuracy typically is better than 2 ppm. The method sensitivity, linearity precision accuracy matrix effect, and limit of detection were also studied. 相似文献
144.
为解决航空遥感相机检焦系统故障分析、元器件选型及提高检焦精度的问题,本文深入研究了基于Ronchi光栅的光电自准直检焦法。首先,归纳总结了国内外航空相机常用的几种检焦方法,对比了每种检焦方法的优缺点。接着,重点介绍了基于Ronchi光栅的光电自准直检焦系统的构成和工作原理,建立了数学模型,模拟了检焦系统在不同像面位置处的输出波形。然后,为衡量离焦程度,提出了离焦评价因子的概念,接着分析了光学系统的衍射效应和像差大小、Ronchi光栅的周期选择及检焦光源的能量分布这三种因素对检焦精度的影响,给出了Ronchi光栅周期的选择方法。最后,通过实验的方法对本文的仿真结果加以验证。实验结果表明:合焦波形的峰峰值占比0.82,对应0.05 mm步长下的平均检焦分辨力约为10%。 相似文献
145.
简要介绍了数字视频监控称重系统的构成、特点及工作原理,论述了利用常用开发工具Delphi、VB编程实现数字视频图像采集的方法。 相似文献
146.
Optical machines with a vision system containing a video camera are designed to perform contact-less three-dimensional measurements. They are becoming more widely used in the industrial sector because of the many possibilities for automation they permit and because of the speed and economies in measurement tasks that can consequently be obtained. Within dimensional control these machines introduce significant characteristics of flexibility, savings and reliability. Therefore the purpose is to identify the principal metrological characteristics of such machines and so characterise the metrological traceability of the measurements obtained from them. The aim is to qualify each part of the optical machine as well as on the whole. Previously, no metrological traceability of this equipment has been provided in primary metrology, either at national (SIT—Sistema di Taratura in Italia—Calibration System in Italy) or at international level (EA–European co-operation for Accreditation). For this reason we develop a mathematical model that permits the evaluation of the measurement uncertainties in the use of such a device. The purpose is to obtain the certification of the measurement results furnished by the optical machine in as broad a context as possible. The experimental results of the tests are introduced for validating the proposed method. This paper provides the basis of the expression of the uncertainty of a measurement result obtained using the optical measurement machines and it shows the necessary requirements for the numerical evaluation of such uncertainty. 相似文献
147.
Michael H. Brill 《Color research and application》2012,37(6):423-423
This poem summarizes the fit‐first method of camera evaluation described in Jim Worthey's “Applications of vectorial color.” The algorithm works with the locus of unit monochromats (LUM) in camera and CIE color‐matching spaces. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011; 相似文献
148.
航空相机是一种重要的机载光电设备,在航空对地测绘等领域有着较为广泛的应用,为方便、直观地对航空相机进行地面检测,设计和实现了一种配套某型航空相机的检测仪系统。根据航空相机地面保障设备任务书和相机与地保设备通讯协议,给出了检测仪系统的功能需求。根据相机的接口要求和系统计算能力的要求,设计了检测仪系统的硬件方案。根据软件部分的功能需求,提出了一种新的分层架构,同时详细论述了软件系统的关键技术,描述了程序的运行流程,给出了检测仪系统的软件设计方案,并在VC6.0环境下实现了检测仪软件系统。针对检测仪的工作方式,设计了测试流程,并根据流程对检测仪进行了详尽的测试,经多次测试,检测仪工作正常。测试结果表明,检测仪系统满足了对其功能的全部要求,运行稳定,操作简便,显示直观,可以应用于航空相机地面保障任务。 相似文献
149.
The aim of this study was to calculate a reasonable correction factor that could be corrected when the sensitivity of each gamma camera is measured and a whole body bone scan is performed as a follow-up examination. Seven pieces of equipment were used to analyse the sensitivity measurements of each gamma camera based on the source sensitivity measurement method recommended by the IAEA. These were BRIGHTVIEW, PRECEDENCE, ECAM, ECAM signature, ECAM Plus, SYMBIA T2 and INFINIA. The 99mTc line source for the sensitivity measurement was generated in 4–7 kcps, which are the common values in a whole body bone scan. All the cameras were equipped with a low-energy and high-resolution parallel multi-hole collimator and set at a window width and photo peak of 15% and 140 keV, respectively. After placing the 99mTc source as closely as possible to the collimator, the count was measured for 60 and 120 seconds to calculate correction factor. To determine if the correction factor calculated using the 99mTc line source could be applied to a whole body bone scan of a real patient, a whole body bone scan was performed on 27 patients before applying the correction factor for comparative analysis. According to the experimental results using the 99mTc line source, the gamma camera sensitivity was the highest for ECAM plus, followed in order by the gamma cameras, ECAM signature, SYMBIA T2, ECAM, BRIGHTVIEW, INFINIA and PRECEDENCE. When the results were used to calculate the correction factor based on the ECAM gamma camera, which had a medium-degree of sensitivity, the respective correction factors were 1·07, 1·05, 1·03, 1·00, 0·90, 0·83 and 0·72. The correction factors calculated based on the experiment using a 99mTc line source were similar to those calculated based on the whole body bone scan. Clinical application of correction factor for measured sensitivity enables estimation of factor correction depending on difference in equipment when image is read, which improves accuracy and reliability of examination, and is expected to be used especially for continuous follow-up examination. 相似文献
150.
本文主要讲述何为基于摄像机的交互技术以及如何在展演建筑中使用该交互技术,使展项更富有感染力和趣味性,使参观者更容易融入其中。 相似文献