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用彩色二维编码测量动态物体三维轮廓的方法 总被引:1,自引:1,他引:0
用红绿蓝颜色的正方形组成二维编码平面,并针其附着在被测物体表面,作为立体视觉测量中的匹配点。用2套光学成像系统获取被测物体的彩色图像,通过计算机图像处理技术找出2个图像中的匹配点,再根据匹配点的视差来获取物体的三维轮廓信息。这一方法特别适于对人体的运动进行三维跟踪测量。 相似文献
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压缩成像是压缩感知理论最重要的研究领域之一.在分析压缩成像中实际测量矩阵与测量值约束的基础上,提出一种基于4-f光学架构的物理可实现的频域相位编码压缩成像方法.该方法利用两路光学架构之间的补偿实现相位编码压缩成像中测量值的非负记录,然后从该测量值精确恢复原图像,解决压缩成像应用中理论与实际物理约束之间不一致的问题.该方法可以单次曝光获得充分的测量值精确重建原图像,不需要其它附加信息,是压缩成像物理实现的一种非常可行的方案.模拟实验证明该方法可以有效地实现图像的压缩测量与超分辨率重建. 相似文献
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传统的图像分块压缩感知(BCS, block compressed sensing)以相同的测量率对各块进行测量,但由于图像的空间特性不同,在重构图像时出现了块效应。通过自适应为各块设定不同的测量率,该问题可得到有效的解决。然而,已有的自适应测量率设定法需要在采集端获得原始数字图像,这在实际的压缩成像(CI, compressive imaging)设备中无法实现。为了克服这一缺陷,提出了一种更易于通过硬件实现的自适应测量率设定法。该方法利用在采集端可获得的CS测量值直接在测量域中估计各图像块的样本方差,再根据各块样本方差自适应地为每块设定测量率并实现码率控制。仿真实验结果表明,该方案重构图像的质量优于非自适应方案,但由于测量域估计块样本方差存在偏差,使其与直接利用块样本方差真实值的自适应方案相比,仍具有一定差距。 相似文献
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A computational framework for approximating boundary surfaces in 3-D biomedical images. 总被引:2,自引:0,他引:2
Lisheng Wang Jing Bai Ping He Pheng-Ann Heng Xin Yang 《IEEE transactions on information technology in biomedicine》2007,11(6):668-682
We propose a new method for detecting and approximating the boundary surfaces in three-dimensional (3-D) biomedical images. Using this method, each boundary surface in the original 3-D image is normalized as a zero-value isosurface of a new 3-D image transformed from the original 3-D image. A novel computational framework is proposed to perform such an image transformation. According to this framework, we first detect boundary surfaces from the original 3-D image and compute discrete samplings of the boundary surfaces. Based on these discrete samplings, a new 3-D image is constructed for each boundary surface such that the boundary surface can be well approximated by a zero-value isosurface in the new 3-D image. In this way, the complex problem of reconstructing boundary surfaces in the original 3-D image is converted into a task to extract a zero-value isosurface from the new 3-D image. The proposed technique is not only capable of adequately reconstructing complex boundary surfaces in 3-D biomedical images, but it also overcomes vital limitations encountered by the isosurface-extracting method when the method is used to reconstruct boundary surfaces from 3-D images. The performances and advantages of the proposed computational framework are illustrated by many examples from different 3-D biomedical images. 相似文献
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图像配准是数字图像处理中的一个重要研究方向。在本文中把SUSAN算法和虚拟圆技术结合起来。提出了一种新的图像配准方法。经过SUSAN算法处理并二值化后的图像去除了原图像中的大部分信息,只保留了明显的边缘信息.这样就大大提高了虚拟圆的提取速度。试验表明这种新的配准方法具有简单、高效并具有较高的准确度等优点。 相似文献
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We propose an asymmetric integral imaging method to adjust the resolution and depth of a three‐dimensional image. Our method is obtained by use of two lenticular sheets with different pitches fabricated under the same F/#. The asymmetric integral imaging is the generalized version of integral imaging, including both conventional integral imaging and one‐dimensional integral imaging. We present experimental results to test and verify the performance of our method computationally. 相似文献
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Since the recent launch of Microsoft Xbox Kinect, research on 3D human pose estimation has attracted a lot of attention in the computer vision community. Kinect shows impressive estimation accuracy and real‐time performance on massive graphics processing unit hardware. In this paper, we focus on further reducing the computation complexity of the existing state‐of‐the‐art method to make the real‐time 3D human pose estimation functionality applicable to devices with lower computing power. As a result, we propose two simple approaches to speed up the random‐forest‐based human pose estimation method. In the original algorithm, the random forest classifier is applied to all pixels of the segmented human depth image. We first use a multi‐scale approach to reduce the number of such calculations. Second, the complexity of the random forest classification itself is decreased by the proposed cascade approach. Experiment results for real data show that our method is effective and works in real time (30 fps) without any parallelization efforts. 相似文献
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在前期工作中,通过对太赫兹光场图像进行离散余弦变换(Discrete Cosine Transform,DCT)滤波和数字重聚焦,初步实现了图像去噪和前后景分割。为了进一步得到质量更高的太赫兹光场原数据并达到更加精确的深度分割效果,改进了实验方案及处理方法,并提出了一种基于极平面图像(Epipolar Plane Image,EPI)的太赫兹光场深度估计方法。在太赫兹图像特性的基础上,给出了深度与视差的关系,并利用局部视差和置信度构建了全局深度图,从而达到了深度估计的目的。最后,在实验中通过10×10的相机阵列采集太赫兹光场数据,得到了准确聚焦于不同平面的重聚焦结果和高分辨度的深度估计图,实现了太赫兹光场成像的深度估计。 相似文献
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Michael Nygaard Pedersen Jürgen Letschnik Lars Schelde Henrik Karstoft Fritz Schurig Ulrich Walter 《International Journal of Satellite Communications and Networking》2013,31(1):39-50
This article describes how to measure a three‐dimensional antenna radiation pattern and the most effective method to achieve this. We present a new automated three‐dimensional measurement scheme, inspired by the seed pattern of a sunflower seed head, where the seed placements are arranged in a way so that rotational symmetry is obtained to compromise the circular shape of a dish antenna radiation pattern in the three‐dimensional space. This new AU–TUM Antenna Radiation Measurement Strategy has produced superior results. It has been shown by this scheme that for instance the three‐dimensional transmission pattern of a dish antenna can be measured automatically and easily checked against present regulations. The generic AU–TUM Antenna Radiation Measurement Strategy was verified on a 4.8‐m Ka‐band dish antenna. It was concluded that a three‐dimensional radiation pattern can be measured two to thirteen times faster than the best performing current strategies. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Image authentication is a type of technique for the content protection of digital images. This technique is able to detect and locate tampered regions on a digital image. In this paper, two self-embedding image authentication approaches are proposed to involve distinctive singular values. Both of them extract self-characteristics of an image as the crucial authentication information for that image. Subsequently, this information is converted into the two dimensional code format and that codes are then embedded into digital image pixels. With the capability of error correction in two dimensional codes, the extracted authentication data, even being detected with a tamper, still can be completely restored and errorless. As well, it can be utilized to detect whether an image has been tampered with or not. According to experimental results, the proposed approaches are superior to other schemes for images that have been modified to a certain attack extent because the authentication data could be completely extracted in more effective way, and the tampered regions could be identified more accurately. In addition, the proposed approaches utilize these complete self-characteristics to restore tampered regions into their original states. 相似文献
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目视万能工具显微镜的影像测量应用研究 总被引:2,自引:1,他引:1
在传统目视万能工具显微镜的基础上,使用光学CCD代替人眼采集图像,增加光栅尺和数显表替代原来的投影式读数器,实现了工件测量CCD图像与光栅尺数据的计算机自动采集。根据CCD图像、光栅尺数据及笛卡尔坐标系理论,建立了测量尺寸与光栅尺数据和图像工件边缘位置的数学模型。应用中值滤波、阈值分割对工件图像进行预处理,采用最小二乘法提取工件边缘的位置和方向,并在此基础上结合工件测量数学模型计算得到了被测工件尺寸。 相似文献
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提出了利用数字图像相关技术测量印刷电路板全场微应变的方法,用于评估电路板由应力所导致的失效风险,克服传统实验测试方法不能有效测量全场应变以及难以给出应变集中区域的不足。设计了基于三维数字图像相关技术和应力加载策略的实验方法,通过所获得的全场主应变分布及局部区域内应变历史曲线来评估电路板的失效风险。实验结果表明,所提出的电路板微应变测量方法的重复性优于100 ,能够有效地获得电路板全场的微应变分布,尤其是能够直观地显示电路板应变超过额定值的区域分布,为改进电路板设计、降低电路板失效风险和保护电子元器件的安全提供了重要的实测数据。 相似文献
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小视场集成成像三维信息获取技术研究 总被引:2,自引:2,他引:0
为了满足利用非接触式方法获取小 视场三维信息的要求, 研究了一种基于集成成像技术获取小视场三维信息的系统,并在借鉴传统微透镜阵列(MLA) 及相机阵列工作模式的基 础上,通过利用精密二维平移台,巧妙地将相机阵列应用于获取小视场三维信息中。系 统工作时,首先将相机 获取的图像合成元素图像阵列,并运用相应的算法实现三维重建与测量。实验结果表明,本 文系统获取了相对清晰、没有相互串扰的元素图像阵列,实现了完整且细节丰富的三维 图像再现;可以 获取待测物体上任意一点的三维坐标,并且三维测量误差保持在0.3 mm 以内。实验结果相对理想,为集成成像技术应用于高精密测量提供了理论基础。 相似文献
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光栅投影成像法经常用于物体的非接触形状测量和形变测量。通过莫尔相移法,可以实时获得物体表面的等高轮廓线。但是在测量高速运动物体三维轮廓图像时误差较大,因为相移法需要拍摄几张经过相移后的变形光栅。在加入了DMD芯片后,可以在CCD的一帧图像时间内完成所有的相移后变形光栅的图像拍摄,有效地降低了高速运动物体三维轮廓成像的误差。 相似文献
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在基于奇异值分解(SVD)算法的基础上,提出了一种基于Strassen矩阵乘法的奇异值分解水印算法;提供了原图像和水印图像的相似性度量方法;给出了本算法与SVD及Block-SVD算法的时间对比分析.实验结果表明本算法的鲁棒性强,速度快,效率高. 相似文献
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图像的几何畸变广泛存在于应用广角镜头的成像系统,畸变的存在尤其不利于基于图像分析的定量分析领域。针对一个基于图像分析的红外角位置测量系统,提出一种实用广角成像系统几何畸变数字实时校正方法,阐述其畸变参数的标定方法,图像的空间变换和灰度插值方法,基于实时性要求,给出畸变校正的算法步骤,实验表明,此广角成像系统几何畸变数字实时校正方法有效提高了角位置测量系统的测量精度,并具有一定的实时性能。 相似文献