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用构造光系统实现3-D形貌测量的研究 总被引:3,自引:0,他引:3
介绍了一个用构造空间二进制编码进行非接触3-D形貌测量的系统。它以一台LCD投影仪为硬件基础,用8幅条纹投影图案对被测物体表面进行空间编码。用CCD摄像机获取物体编码信息,用基于单一像素的三角法原理从摄像机图像中获取三维形貌数据。指出了二进制编码图案生成软件及其生成的条纹图案的特点。为了提高3-D形貌测量的精度,分析了由摄像机和投影仪镜头造成的误差,建立了它们的透镜误差矫正公式,并取得了良好的实验结果。 相似文献
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由于传感器成像视场范围的局限性,双目视觉传感器在一次成像中往往不能获得大尺寸物体的整体形貌测量结果,鉴于此,研究并实现了一种通过建立全局控制网来实现对大尺寸物体的三维形貌进行测量的方法。实验结果表明:基于全局控制网的测量方法速度快、精度高,间接地扩大了双目视觉传感器的测量范围,并且有效地克服了大尺寸三维形貌测量拼接精度低的缺点。该方法适用于大尺寸物体的三维形貌测量,能够快速、简单、精确地获得被测物体表面特征点的相对位置关系和三维尺寸信息,进而恢复被测物体的三维形貌。 相似文献
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在无人机为载体的基础上进行对目标场景的三维重建,就是结合无人机和计算机视觉技术,利用无人机操作灵活性,视角可控制性等优点.为实现更加完整的三维模型的重建,提出一种基于多图像拼接三维重建算法.基本思路是在无人机为载体的基础上,从不同方向获取目标物体的图像,通过自标定方法获取相机内参数,采用图像拼接融合技术对多幅图像分析、合成,从而最大限度地对建筑物场景的各种特征信息的描述.进一步对拼接融合后的图像进行特征点提取和点云匹配,从而获取全景图空间特征点三维点云,获得一个较为真实的重构对象的三维模型.实验结果表明,改进后的重构方法的精度较高,适合在许多场景三维重建的应用. 相似文献
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本文提出了利用M系列编码光栅投影获取物体的三维形状的新方法。通过实验证明了本方法的有效性。本方法只需要两张图像,能够快速地获取物体形状。 相似文献
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Optical microscopy allows a magnified view of the sample while decreasing the depth of focus. Although the acquired images from limited depth of field have both blurred and focused regions, they can provide depth information. The technique to estimate the depth and 3D shape of an object from the images of the same sample obtained at different focus settings is called shape from focus (SFF). In SFF, the measure of focus–sharpness–is the crucial part for final 3D shape estimation. The conventional methods compute sharpness by applying focus measure operator on each 2D image frame of the image sequence. However, such methods do not reflect the accurate focus levels in an image because the focus levels for curved objects require information from neighboring pixels in the adjacent frames too. To address this issue, we propose a new method based on focus adjustment which takes the values of the neighboring pixels from the adjacent image frames that have approximately the same initial depth as of the center pixel and then it re-adjusts the center value accordingly. Experiments were conducted on synthetic and microscopic objects, and the results show that the proposed technique generates better shape and takes less computation time in comparison with previous SFF methods based on focused image surface (FIS) and dynamic programming. Microsc. Res. Tech., 2009. © 2008 Wiley-Liss, Inc. 相似文献
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In this article, we propose a new shape from focus (SFF) method to estimate 3D shape of microscopic objects using surface orientation cue of each object patch. Most of the SFF algorithms compute the focus value of a pixel from the information of neighboring pixels lying on the same image frame based on an assumption that the small object patch corresponding to the small neighborhood of a pixel is a plane parallel to the focal plane. However, this assumption fails in the optics with limited depth of field where the neighboring pixels of an image have different degree of focus. To overcome this problem, we try to search the surface orientation of the small object patch corresponding to each pixel in the image sequence. Searching of the surface orientation is done indirectly by principal component analysis. Then, the focus value of each pixel is computed from the neighboring pixels lying on the surface perpendicular to the corresponding surface orientation. Experimental results on synthetic and real microscopic objects show that the proposed method produces more accurate 3D shape in comparison to the existing techniques. 相似文献
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为保证在基于点特征的三维运动分析中运动物体不同时刻任意物方特征点的对应,对该过程中存在的图像运动-立体匹配问题进行了研究。提出了运动-立体匹配相结合,分阶段的运动-立体双匹配约束的方法。即采用松弛法点特征匹配算法完成图像间的基本匹配,通过运动-立体双匹配约束完成运动物体特征点的对应。给出了一组真实的实验数据,结果表明:该算法总的正确率达76.5%,基本达到了三维运动物体定位跟踪中特征点对应的要求。 相似文献
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针对微型机电系统(MEMS)的三维测量,显微镜或光学轮廓干涉仪等传统方法存在显微测量精度低、设备成本高等问题,且当结构含有较多断裂面时,解包裹算法效果欠佳。本文提出一种基于多图像融合的MEMS显微三维测量方法。不同于多角度显微三维测量方法,本研究首先利用单目显微镜,通过单一轴向移动获取一系列测量目标深度信息的单一角度图像,并利用去雾算法对图像进行预处理,实现了去噪和有效信息提取的目的;然后通过聚焦测度算法获取待测对象的深度信息;最后利用数据处理软件进行三维拟合。基于上述原理,本文以焦平面阵列(FPA)作为待测目标进行了测量实验。本文提出的三维测量方法和图像处理算法可获得更准确的FPA形貌,可清晰显示反射面与支腿部分及反射面上的释放孔,测得FPA的支腿长度为110.6μm,每个反射面的像元尺寸为120.8μm×70.8μm,与设计值基本吻合,解决了断裂面难以测量的问题,同时降低了微结构测量的难度和成本。单目显微镜单向移动的多图像融合测量技术对MEMS的三维形貌测量具有重要意义,去雾算法在图像融合与三维测量的图像处理也有很好的应用价值。 相似文献
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提出了一种基于变分理论的由稠密光流检测图像中目标物体三维运动与结构的直接方法。首先在透视投影模型下将目标物体的三维运动参数与图像光流联系起来,构建了一个未知量是三维运动参数的能量函数,然后使用变分方法直接求出图像中目标运动物体的三维运动参数,最后由求出的三维运动参数恢复物体表面的三维稠密结构及图像光流。该方法在对目标物体进行三维运动检测时省略了"光流计算"这一中间过程,避免了图像光流计算给三维运动检测结果带来的误差影响和时间消耗。多组实验证明该算法具有较高的计算精度、较好的鲁棒性和较快的计算效率。 相似文献
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Inspection of weld shape based on the shape from shading 总被引:2,自引:1,他引:1
Du Quanying Chen Shanben Lin Tao 《The International Journal of Advanced Manufacturing Technology》2006,27(7-8):667-671
The weld bead shape is crucial for weld quality. Automatic inspection on the 3D shape of a weld bead is achieved by recording
the image of the weld bead with an optical sensing method and then calculating the 3D shape parameters with a shape-from-shading
technology based on a single image in the computer-vision domain. The paper first introduces a method of shape from shading
based on a single image and puts forward its implementation. It then presents the improved measures of the original algorithm
according to the defects of the computed results and finds accuracy compared with the former method by a synthetic image.
Finally, the improved algorithm is applied to the surface height reconstruction of weld bead successfully . 相似文献