Crosstalk characterization of PMD pixels using the spatial response function at subpixel level
Crosstalk characterization of PMD pixels using the spatial response function at subpixel level
复制标题
使用子像素级空间响应函数表征 PMD 像素的串扰
DOI：
10.1117/12.2083353
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
O. Loffeld
中科院分区：
文献类型：
--
作者：
M. Heredia Conde;K. Hartmann;O. Loffeld
飞行时间相机已经成为最广泛使用的低成本3d传感设备之一。它们中的大多数实际上并没有测量光线到达物体并返回相机所需的时间，而是测量相对于参考信号的相位差。这需要具有复杂空间结构的特殊像元，如PMD像元，能够对场景反射的输入信号与参考信号之间的互相关函数进行采样。复杂的结构，加上像素内电子器件的存在，以及对两个像素通道的紧凑读出电路的需求，表明系统串扰效应将出现在这种设备中。我们首次利用PMD像素的亚像素空间响应的最新结果来检测和表征串扰的发生。通过对每个敏感区域的像素间空间响应的集成，确定了定义良好的串扰模式并进行了定量表征。我们将串扰问题转化为图像卷积，并提供反卷积核用于从串扰中清除PMD原始图像。在真实PMD原始图像上的实验表明，我们的结果可以用于消除高对比度图像区域串扰引起的低通滤波。应用我们的核来撤消串扰效应导致在关键区域的深度RMSE降低高达50%。
Time-of-Flight cameras have become one of the most widely-spread low-cost 3D-sensing devices. Most of them do not actually measure the time the light needs to hit an object and come back to the camera, but the difference of phase with respect to a reference signal. This requires special pixels with complex spatial structure, such as PMD pixels, able to sample the cross-correlation function between the incoming signal, reflected by the scene, and the reference signal. The complex structure, together with the presence of in-pixel electronics and the need for a compact readout circuitry for both pixel channels, suggests that systematic crosstalk effects will come up in this kind of devices. For the first time, we take profit of recent results on subpixel spatial responses of PMD pixels to detect and characterize crosstalk occurrences. Well-defined crosstalk patterns have been identified and quantitatively characterized through integration of the inter-pixel spatial response over each sensitive area. We cast the crosstalk problem into an image convolution and provide deconvolution kernels for cleaning PMD raw images from crosstalk. Experiments on real PMD raw images show that our results can be used to undo the lowpass filtering caused by crosstalk in high contrast image areas. The application of our kernels to undo crosstalk effects leads to reductions of the depth RMSE up to 50% in critical areas.
动态 3D 成像
DOI：
10.1007/978-3-642-03778-8
发表时间：
2009
期刊：
Lecture Notes in Computer Science
影响因子：
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作者：
A. Kolb;R. Koch
通讯作者：
R. Koch
PMD 像素的子像素空间响应
DOI：
10.1109/ist.2014.6958492
发表时间：
2014
期刊：
2014 IEEE International Conference on Imaging Systems and Techniques (IST) Proceedings
影响因子：
--
作者：
M. Heredia Conde;K. Hartmann;O. Loffeld
通讯作者：
O. Loffeld