Novel registration algorithm for 3-D images captured from multiple views of object surface

A novel algorithm of 3-D surface image registration is proposed. It makes use of the array information of 3-D points and takes vector/vertex-like features as the basis of the matching. That array information of 3-D points can be easily obtained when capturing original 3-D images. The iterative least-mean-squared （LMS） algorithm is applied to optimizing adaptively the transformation matrix parameters. These can effectively improve the registration performance and hurry up the matching process. Experimental results show that it can reach a good subjective impression on aligned 3-D images. Although the algorithm focuses primarily on the human head model, it can also be used for other objects with small modifications.

Research on a Watermarking Algorithm for Remote Sensing Images Resist Screen Capture Attacks in Urban Planning Information Management

Remote Sensing data, as an essential urban basic information in urban planning, has the characteristics of large information capacity, real time, high update speed and accuracy. Because of urban spatial information involving multi-faceted public and public interests, its data security is very important. The use of digital watermarking technology can effectively protect the secu-rity of urban planning basic data. In practical applications, the “screen capture” poses a great threat to the security of remote sensing image. In order to resist the screen capture attacks, the QR code watermark information is encoded and converted, and combined with a circular angle template watermark, a digital watermarking algorithm for remote sensing images in urban planning information management is proposed. And the proposed algorithm is experimentally verified. Experiments show that the algorithm is robust against screen capture attacks, and provide security guarantee for urban construction and management.

Hcable for Time-Lapse Seismic Monitoring of Marine Carbon Capture and Storage

To ensure project safety and secure public support, an integrated and comprehensive monitoring program is needed within a carbon capture and storage(CCS) project. Monitoring can be done using many well-established techniques from various fields, and the seismic method proves to be the crucial one. This method is widely used to determine the CO_(2) distribution, image the plume development, and quantitatively estimate the concentration. Because both the CO_(2) distribution and the potential migration pathway can be spatially small scale, high resolution for seismic imaging is demanded. However, obtaining a high-resolution image of a subsurface structure in marine settings is difficult. Herein, we introduce the novel Hcable(Harrow-like cable system) technique, which may be applied to offshore CCS monitoring. This technique uses a highfrequency source(the dominant frequency>100 Hz) to generate seismic waves and a combination of a long cable and several short streamers to receive seismic waves. Ultrahigh-frequency seismic images are achieved through the processing of Hcable seismic data. Hcable is then applied in a case study to demonstrate its detailed characterization for small-scale structures. This work reveals that Hcable is a promising tool for timelapse seismic monitoring of oceanic CCS.

Neural hand reconstruction using an RGB image

Background This study presents a neural hand reconstruction method for monocular 3D hand pose and shape estimation.Methods Alternate to directly representing hand with 3D data,a novel UV position map is used to represent a hand pose and shape with 2D data that maps 3D hand surface points to 2D image space.Furthermore,an encoder-decoder neural network is proposed to infer such UV position map from a single image.To train this network with inadequate ground truth training pairs,we propose a novel MANOReg module that employs MANO model as a prior shape to constrain high dimensional space of the UV position map.Results The quantitative and qualitative experiments demonstrate the effectiveness of our UV position map representation and MANOReg module.

Operating limits and features of direct air capture on K_(2)CO_(3)/ZrO_(2) composite sorbent

Potassium carbonate-based sorbents are prospective materials for direct air capture(DAC).In the present study,we examined and revealed the influence of the temperature swing adsorption(TSA)cycle conditions on the CO_(2) sorption properties of a novel aerogel-based K_(2)CO_(3)/ZrO_(2) sorbent in a DAC process.It was shown that the humidity and temperature drastically affect the sorption dynamic and sorption capacity of the sorbent.When a temperature at the sorption stage was 29℃ and a water vapor pressure P_(H2O) in the feed air was 5.2 mbar(1 bar=105 Pa),the composite material demonstrated a stable CO_(2) sorption capacity of 3.4%(mass).An increase in sorption temperature leads to a continuous decrease in the CO_(2) absorption capacity reaching a value of 0.7%(mass)at T=80℃.The material showed the retention of a stable CO_(2) sorption capacity for many cycles at each temperature in the range.Increasing PH2O in the inlet air from 5.2 to 6.8 mbar leads to instability of CO_(2) sorption capacity which decreases in the course of 3 consecutive TSA cycles from 1.7%to 0.8%(mass)at T=29℃.A further increase in air humidity only facilitates the deterioration of the CO_(2) sorption capacity of the material.A possible explanation for this phenomenon could be the filling of the porous system of the sorbent with solid reaction products and an aqueous solution of potassium salts,which leads to a significant slowdown in the CO_(2) diffusion in the composite sorbent grain.To investigate the regeneration step of the TSA cycle in situ,the macro ATRFTIR(attenuated total reflection Fourier-transform infrared)spectroscopic imaging was applied for the first time.It was shown that the migration of carbonate-containing species over the surface of sorbent occurs during the thermal regeneration stage of the TSA cycle.The movement of the active component in the porous matrix of the sorbent can affect the sorption characteristics of the composite material.The revealed features make it possible to formulate the requirements and limitations that need to be taken into account for the practical implementation of the DAC process using the K_(2)CO_(3)/ZrO_(2) composite sorbent.

Single-image night haze removal based on color channel transfer and estimation of spatial variation in atmospheric light

The visible-light imaging system used in military equipment is often subjected to severe weather conditions, such as fog, haze, and smoke, under complex lighting conditions at night that significantly degrade the acquired images. Currently available image defogging methods are mostly suitable for environments with natural light in the daytime, but the clarity of images captured under complex lighting conditions and spatial changes in the presence of fog at night is not satisfactory. This study proposes an algorithm to remove night fog from single images based on an analysis of the statistical characteristics of images in scenes involving night fog. Color channel transfer is designed to compensate for the high attenuation channel of foggy images acquired at night. The distribution of transmittance is estimated by the deep convolutional network DehazeNet, and the spatial variation of atmospheric light is estimated in a point-by-point manner according to the maximum reflection prior to recover the clear image. The results of experiments show that the proposed method can compensate for the high attenuation channel of foggy images at night, remove the effect of glow from a multi-color and non-uniform ambient source of light, and improve the adaptability and visual effect of the removal of night fog from images compared with the conventional method.

基于Context Capture和Inpho软件的真正射影像生产研究

针对传统方法生产数字真正射影像效率低、质量差、精度低的问题,本文采用倾斜摄影空三加密成果xml文件,利用C语言开发了空三转换软件,将xml文件中的影像外方位元素和相机参数进行提取,并导出对应的畸变改正影像,然后将其引入inpho软件进行数字真正射影像的生产。通过实际项目数据对比可知,本文的方法生产的数字真正射影像成果质量好、精度高,且较传统方法效率高,为数字真正射影像生产提供了有效的方案。

Panoramic Imaging System Inspired by Insect Compound Eyes

Inspired by the unique structure of insect compound eyes,a multi-channel image acquisition system is designed to photograph a cylindrical panorama of its surroundings with one shot. The hardware structure consists of an embedded ARM system and one array of 16 micro-image sensors. The system achieves the synchronization of captured photos in 10 ms,as well as 10 f /s video capture. The software architecture includes the TCP /IP protocol,video capture procedures in"Poll/Read"or"video streaming"modes,thread pool monitoring in multi-threading mutex,synchronization control with the"event""mutex signal"and"critical region"functions,and a synthetic image algorithm characterized by its portability,modularity,and remote transmission. The panoramic imaging system is expected to be a vision sensor for mobile robotics.

Computer generated hologram from full-parallax 3D image data captured by scanning vertical camera array(Invited Paper)

Full-parallax light-field is captured by a small-scale 3D image scanning system and applied to holographic display. A vertical camera array is scanned horizontally to capture full-parallax imagery, and the vertical views between cameras are interpolated by depth image-based rendering technique. An improved technique for depth estimation reduces the estimation error and high-density light-field is obtained. The captured data is employed for the calculation of computer hologram using ray-sampling plane. This technique enables high-resolution display even in deep 3D scene although a hologram is calculated from ray information, and thus it makes use of the important advantage of holographic 3D display.

弱引力小天体的自主捕获与相对导航方法

远距离自主捕获与近距离高精度自主相对导航是小天体探测任务中的关键问题,并且目标尺寸越小,问题越突出。首先,针对数万千米到数千千米远距离范围内的星空背景暗弱目标难以识别的问题,提出综合利用运动学和亮度的全自主捕获和识别方法,可以实现距离大范围变化的快速准确捕获,具备了3万千米以远捕获10等星暗弱目标的能力;其次,针对数千到数十千米范围交会段视线测量可观性不足的问题,提出基于视线和轨迹机动一体化设计的相对导航方法,在考虑燃料消耗的前提下有效地提高了轨迹可观性,实现了交会段优于5%精度的相对位置导航;最后,针对近距离不规则小天体表面附近的相对导航问题,提出基于图像陆标和点云特征相结合的光学导航方法,可同时适应阳照区和阴影区的探测需求,并结合基于多源数据融合的弱引力小天体重力场反演方法,进一步提高近距相对导航的精度,近距采样相对位置优于1 m,相对速度优于1 cm/s。对所提出的方法进行了数学和物理的仿真验证。提出的方法有效解决了小天体探测中的高精度相对导航问题,也能适用于数十米量级直径大小和明暗快速交替变化的小天体着陆探测任务。

利用无标记动作捕捉技术对立定跳远测量的研究

目的:旨在探究无标记动作捕捉技术在立定跳远距离测量中的应用。方法:采用RGB-D深度相机进行动作捕捉,运用关键帧提取、图像分割和边缘检测等图像处理技术,结合机器学习算法,实现无标记精准测量立定跳远距离,并通过信效度分析检证其精准性和可靠性。结果:通过51个标准距离重复测量,重测信度检验得到克隆巴赫系数α=0.999和组内相关系数ICC=0.998,重测精准性达到99.64%;通过306次立定跳远试跳实测,标准效度检验的Pearson相关系数r=0.999,稳定可靠性达到99.69%。结论:本研究成功开发并验证了一种基于无标记动作捕捉技术的立定跳远距离测量方法,极高的精准性和可靠性展示了该方法的创新性和实用价值。

基于姿态估计与深度图像的啦啦操运动员动作捕捉方法设计

为了对啦啦操运动员的动作进行有效的捕捉与识别,提出一种基于姿态估计与深度图像(PE-DI)的啦啦操运动员动作捕捉方法 .该方法采用深度摄像头收集啦啦操运动员的运动数据,并通过利用深度图像来增强三维空间的动作重建效果,接着利用姿态估计算法分析运动员的动作精度和稳定性.结果显示,动作识别率对比中,PE-DI算法、NN-BV算法、SPR-DL算法与Multi-Scale Feature算法在五次实验中的平均识别率分别为99.24%、97.18%、94.16%与90.21%.最后PE-DI算法运行下啦啦操运动员起势、跳跃、鞠躬与转身四个动作的均被捕捉划分于正确区域内,显著优于其他算法.实验结果表明,PE-DI算法能够对啦啦操运动员的动作进行较高精度的捕捉,为啦啦操运动员的训练与表演提供有效的技术支持.

车辆图像智能抓拍系统的设计与实现

文中以车道图像智能抓拍系统为分析对象,研究了车辆智能抓拍系统的设计与实现。合理设计车道图像智能抓拍,能满足交通运行需求,使驾驶人员按照交通规则安全驾驶,提升交通安全系数,减少违章行为,避免给交通安全造成影响。

CO_(2)吸收过程中气相分压对Rayleigh对流传质特性的影响

界面浓度梯度导致的Rayleigh对流现象能够显著提高CO_(2)吸收过程的传质速率,然而目前该过程的传质强化机制尚未清晰。为探究Rayleigh对流传质过程的强化机制,本文以水吸收CO_(2)过程为研究对象,基于粒子图像测速技术(PIV)和激光诱导荧光技术(LIF)实现了不同气相CO_(2)分压条件下界面对流的可视化与定量测量。实验发现,界面平均浓度在对流发生的临界时刻会瞬间下降并在有序的自组织结构形成后上升,最终的界面平均浓度会随着气相CO_(2)分压减小而减小;对流发生后,系统传质能力的提高分为两个阶段,涡量场在有序的自组织结构形成前起主导作用,有序的自组织结构形成后,系统传质能力的提高则是由涡量场与界面浓度共同作用的结果;有序的自组织结构形成后,不同系统的平均瞬时传质系数与平均涡量具有很强的相关性,表明浓度场与速度场相互作用形成的涡量场在对流传质强化过程中发挥着重要作用。

基于ZYNQ的内窥镜图像处理系统设计

针对传统医用内窥镜系统体积大、成本高等问题,论文设计并实现了基于ZYNQ的内窥镜图像处理系统。系统以Xilinx公司推出的ZYNQ7020为主控芯片,OV6946为图像采集摄像头,OV426为图像解码芯片,FPGA为图像处理端接收RAW格式图像,去除图像坏点后做颜色插值转换为彩色RGB图像,再做白平衡处理还原图像的真实色彩,最后增强图像对比度提高可视效果,图像经AXI总线存储到DDR3中,最后通过HDMI显示。PS端对FPGA进行初始化配置,协助完成图像采集和存储工作。由测试结果可以得出,该系统设计简洁,占用资源少,处理实时性高,图像处理结果满足预期要求,具有良好的应用前景。

左心室室间隔瘢痕对左束支起搏术实现左束支夺获的影响

目的:通过心脏磁共振探索室间隔瘢痕对左束支起搏实现左束支夺获的影响。方法:回顾性分析52例拟接受左束支起搏的患者,根据是否实现左束支夺获分为失败组和成功组,并通过心脏磁共振对室间隔瘢痕分节段进行评分。结果:上室间隔瘢痕评分是预测左束支夺获成功与否的独立预测因子。当上室间隔的瘢痕<25%,左束支夺获的成功率为100%。而当瘢痕≥50%,左束支夺获的失败率为100%。结论:采用心脏磁共振评估上室间隔瘢痕有助于预测左束支起搏手术成功与否,为手术的顺利实施提供可靠的参考依据。

应急广播监管系统设计与思考

针对应急广播体系建设中效果监测评估系统规范不统一、监测内容有限的实际情况,结合行业的监管需求,介绍应急广播监管系统的设计与实现方法,为行业提供借鉴与参考。

相控阵超声相位相干成像(PCI)检测原理及应用

为了了解相控阵超声相位相干成像(PCI)检测技术在工业无损检测应用中的效果及特点,详细介绍了相控阵超声全聚焦成像与相位相干成像(PCI)检测技术的基本原理,从原理上分析了PCI检测技术与全聚焦成像检测技术的差异性。通过试验测试了PCI检测技术对点状缺陷、面状缺陷与体积状缺陷的检测特点及效果,根据得到的检测效果,展示了PCI检测技术对于不同类型缺陷的检测优势与不足,以推动该技术在工业无损检测中的正确应用。

基于条件GAN的复杂动作图像轮廓智能捕捉研究

针对复杂动作本身的高动态性和多样性,传统的图像处理方法难以准确捕捉其轮廓,文中研究基于条件GAN的复杂动作图像轮廓智能捕捉方法,精准了解动作执行情况。该方法利用像素覆盖分割模型来分割原始复杂动作图像,获取复杂动作目标图像,将其作为约束条件输入生成器,经过编解码器处理后输出虚假复杂动作图像轮廓生成结果,判别器将生成器输出的虚假轮廓和真实复杂动作图像轮廓作为输入,在损失函数作用下进行真假判别,并采用反向传输的方式对生成器和判别器的参数进行迭代更新,实现最佳复杂动作图像轮廓智能捕捉。结果显示:该方法可以有效捕捉不同类型的复杂动作图像轮廓,通过消融实验证明,改进后的条件GAN模型可显著提升捕捉到的图像轮廓的平滑度和形状保持性,为捕捉复杂动作图像轮廓提供了一种新方法。

基于条件GAN的人体复杂动作轮廓智能捕捉研究

为了精确捕捉人体在各种复杂动作中的姿态变化,并减少动作轮廓捕捉的误判和漏判情况,研究一种基于条件GAN的人体复杂动作轮廓智能捕捉方法。构建人体复杂动作图像前景模型,利用该前景模型去除人体复杂动作图像内的干扰背景,获得其前景图像。将人体复杂动作前景图像输入到条件GAN模型内,该模型使用生成器,依据叠加条件提取人体复杂动作前景图像特征,并生成人体复杂动作轮廓图像,将该轮廓图像输入到判别器内,判别器对生成器生成的人体复杂动作轮廓图像进行判别,输出其判别值;同时,生成器依据该判别值对人体复杂动作轮廓图像进行调整和优化。生成器和判别器不断对抗,当条件GAN模型的损失函数达到最小时,生成器输出最终人体复杂动作轮廓图像,实现人体复杂动作轮廓智能捕捉。实验结果表明,所提方法可有效捕捉人体复杂动作轮廓,且智能捕捉的人体复杂动作轮廓周长与其实际轮廓周长差异较小。