为了达成显示动态三维地理信息系统(Geographic Information System,GIS)场景的立体视差和运动视差的目的。本文讲述了如何利用投影仪阵列构成的多视点自由立体投影显示系统,重点阐述了三维GIS信息的在PC端的同步传输以及投影图像的校...为了达成显示动态三维地理信息系统(Geographic Information System,GIS)场景的立体视差和运动视差的目的。本文讲述了如何利用投影仪阵列构成的多视点自由立体投影显示系统,重点阐述了三维GIS信息的在PC端的同步传输以及投影图像的校正。并以此方法构建的系统在展示GIS信息时得到了较好的裸眼立体视觉体验。展开更多
在多视点视频系统中,用户端的随机访问性能是表征交互能力的一个重要指标。当用户进行随机访问时,需要快速确定相应的解码路径,以快速有效地获得相应视点与时刻的图像帧。针对H.264多视点视频系统中随机访问效率不高这个情况,分析了传...在多视点视频系统中,用户端的随机访问性能是表征交互能力的一个重要指标。当用户进行随机访问时,需要快速确定相应的解码路径,以快速有效地获得相应视点与时刻的图像帧。针对H.264多视点视频系统中随机访问效率不高这个情况,分析了传统多视点视频系统随机访问解码路径的计算方法,讨论了其中存在的非最优解码路径问题,提出帧等级矩阵的概念。然后,提出针对HBP(hierarchical B pictures)这种具有代表性的多视点视频编码预测结构的解码路径计算快速算法。实验结果表明,所提算法能获得较优解码路径,从而有效地提高随机访问性能,降低解码复杂度。展开更多
This letter proposes a new kind of image quality philosophy—Modulate Quality based on Fixation Points (MQFP) based on Human Visual System (HVS) model. Dissimilar to the former HVS-based quality assessment, the new me...This letter proposes a new kind of image quality philosophy—Modulate Quality based on Fixation Points (MQFP) based on Human Visual System (HVS) model. Dissimilar to the former HVS-based quality assessment, the new measure emphasizes particularly on modeling the jumping phenomenon of human sight instead of modeling the visual perception of human. In other words, to model the HVS using fixation points and stay-frequency instead of Contrast Sensitive Function (CSF) etc. which models the visual perception of HVS. The experiment on various frequency-distortion images indicates that the new measure is correlated with the subjective judgment more than the former HVS-based measure and is a robust measure.展开更多
Velocity of detonation （VOD） is one of the most important properties of explosives and indicates perfor- mances of explosives in real time. With the development of blast monitoring systems, continuous VOD monitoring...Velocity of detonation （VOD） is one of the most important properties of explosives and indicates perfor- mances of explosives in real time. With the development of blast monitoring systems, continuous VOD monitoring systems are recently available. The VOD measurement in holes helps in comparing and eval- uating relative performances of explosives. The purpose of this paper is a framework for selecting the type of explosives. This paper analyses the results of VOD measurements, carried out at the limestone quarry （Zrnotiti （~~rni kal）, Slovenia. Experiments were conducted to measure VOD in blast holes which were loaded with ANFO, heavy ANFO and emulsion explosives. The explosives are produced at the point of use with mobile equipment. In this study, resistance wire continuous VOD measurement system MicroTrap, VODSYS-4 from MREL was used and framework for selection the type of explosives has been suggested.展开更多
In the PnP problem,the imaging devices follow the perspective rule and the imaging rays pass through a common point. However,there are many new imaging devices being developed for robot navigation or other fields with...In the PnP problem,the imaging devices follow the perspective rule and the imaging rays pass through a common point. However,there are many new imaging devices being developed for robot navigation or other fields with the advance in imaging technologies for machine vision. These devise are not necessarily being designed to follow the perspective rule in order to satisfy some design criterion and,thus, the imaging rays may not pass through a common point.Such generalized imaging devices may not be perspective and, therefore, their poses cannot be estimated with traditional perspective technique.Using the Wu-Ritt＇s zero decomposition method,the main component for the nonperspective-three-point problem is given. We prove that there are at most eight solutions in the general case and give the solution classification for the NP3P problem.展开更多
The registration of point cloud is important for large object measurement.A measurement method for coordinate system transformation based on robot is proposed in this paper.Firstly,for obtaining extrinsic parameters,t...The registration of point cloud is important for large object measurement.A measurement method for coordinate system transformation based on robot is proposed in this paper.Firstly,for obtaining extrinsic parameters,the robot moves to three different positions to capture the images of three targets.Then the transformation matrix X between camera and tool center point(TCP) coordinate systems can be calculated by using the known parameters of robot and the extrinsic parameters,and finally the multi-view coordinate system can be transformed into robot coordinate system by the transformation matrix X.With the help of robot,the multi-view point cloud can be easily transformed into a unified coordinate system.By using robot,the measurement doesn't need any mark.Experimental results show that the method is effective.展开更多
文摘为了达成显示动态三维地理信息系统(Geographic Information System,GIS)场景的立体视差和运动视差的目的。本文讲述了如何利用投影仪阵列构成的多视点自由立体投影显示系统,重点阐述了三维GIS信息的在PC端的同步传输以及投影图像的校正。并以此方法构建的系统在展示GIS信息时得到了较好的裸眼立体视觉体验。
文摘在多视点视频系统中,用户端的随机访问性能是表征交互能力的一个重要指标。当用户进行随机访问时,需要快速确定相应的解码路径,以快速有效地获得相应视点与时刻的图像帧。针对H.264多视点视频系统中随机访问效率不高这个情况,分析了传统多视点视频系统随机访问解码路径的计算方法,讨论了其中存在的非最优解码路径问题,提出帧等级矩阵的概念。然后,提出针对HBP(hierarchical B pictures)这种具有代表性的多视点视频编码预测结构的解码路径计算快速算法。实验结果表明,所提算法能获得较优解码路径,从而有效地提高随机访问性能,降低解码复杂度。
基金Supported by the National Natural Science Foundation of China (No.60372068) and theGuangdong Province Science Foundation (No.011628).
文摘This letter proposes a new kind of image quality philosophy—Modulate Quality based on Fixation Points (MQFP) based on Human Visual System (HVS) model. Dissimilar to the former HVS-based quality assessment, the new measure emphasizes particularly on modeling the jumping phenomenon of human sight instead of modeling the visual perception of human. In other words, to model the HVS using fixation points and stay-frequency instead of Contrast Sensitive Function (CSF) etc. which models the visual perception of HVS. The experiment on various frequency-distortion images indicates that the new measure is correlated with the subjective judgment more than the former HVS-based measure and is a robust measure.
文摘Velocity of detonation （VOD） is one of the most important properties of explosives and indicates perfor- mances of explosives in real time. With the development of blast monitoring systems, continuous VOD monitoring systems are recently available. The VOD measurement in holes helps in comparing and eval- uating relative performances of explosives. The purpose of this paper is a framework for selecting the type of explosives. This paper analyses the results of VOD measurements, carried out at the limestone quarry （Zrnotiti （~~rni kal）, Slovenia. Experiments were conducted to measure VOD in blast holes which were loaded with ANFO, heavy ANFO and emulsion explosives. The explosives are produced at the point of use with mobile equipment. In this study, resistance wire continuous VOD measurement system MicroTrap, VODSYS-4 from MREL was used and framework for selection the type of explosives has been suggested.
基金This project was partially supported by Shuxue Tianyuan Foundation(No.10526031).
文摘In the PnP problem,the imaging devices follow the perspective rule and the imaging rays pass through a common point. However,there are many new imaging devices being developed for robot navigation or other fields with the advance in imaging technologies for machine vision. These devise are not necessarily being designed to follow the perspective rule in order to satisfy some design criterion and,thus, the imaging rays may not pass through a common point.Such generalized imaging devices may not be perspective and, therefore, their poses cannot be estimated with traditional perspective technique.Using the Wu-Ritt＇s zero decomposition method,the main component for the nonperspective-three-point problem is given. We prove that there are at most eight solutions in the general case and give the solution classification for the NP3P problem.
基金supported by the National Natural Science Foundation of China(Nos.60808020 and 61078041)the National Science and Technology Support Program(No.2014BAH03F01)+2 种基金the Tianjin Research Program of Application Foundation and Advanced Technology(No.10JCYBJC07200)the Tianjin Small and Medium Enterprise Innovation Fund(No.12ZXCXGX11800)the Technology Program of Tianjin Municipal Education Commission(No.20130324)
文摘The registration of point cloud is important for large object measurement.A measurement method for coordinate system transformation based on robot is proposed in this paper.Firstly,for obtaining extrinsic parameters,the robot moves to three different positions to capture the images of three targets.Then the transformation matrix X between camera and tool center point(TCP) coordinate systems can be calculated by using the known parameters of robot and the extrinsic parameters,and finally the multi-view coordinate system can be transformed into robot coordinate system by the transformation matrix X.With the help of robot,the multi-view point cloud can be easily transformed into a unified coordinate system.By using robot,the measurement doesn't need any mark.Experimental results show that the method is effective.
