Optimized dithering fringe pattern is a promising method for high-speed, high-accuracy three-dimensional shape measurement. The recently proposed dithering optimization technology optimizes the fringe quality in either phase domain or intensity domain according to their objective functions. Phase-based optimization is direct and effective, but it is sensitive to projector defocusing levels. Intensity-based optimization is robust to projector defocusing levels, but it does not fully improve the phase quality. In practice, it is difficult to control defocusing levels so it is still a challenge to get high quality fringe patterns which affects the measurement quality under different defocusing levels. In order to get high-quality binary dithered patterns which are robust to defocusing levels, this paper proposes a weight object function. This function combines two parts: a global intensity part and a local structure part. The global intensity measurement is based on the normalized mean squared error. The local structure measurement is based on residual error of intensity. To generate high quality fringe patterns, the weight object function is applied to the best patch framework. Both simulation and experimental results demonstrate that the phase-based optimization method and the proposed method perform better than the intensity-based optimization method under nearly focused. However the quality of measurement results from phase-based optimization will decrease with the defoucsing levels increasing. The proposed method is robust to the defocusing levels and it can still reduce the phase error when the projector is strongly defocused. The proposed method can get high-quality binary dithered patterns under different defocusing levels by combining global similarity and local residual error of intensity. It inherits the merits of binary fringe pattern so that gamma calibration of projector is not required. In practice, the proposed method can be used to generate high quality fringe patterns. The experiment results verify that the proposed method can get better measurement results without considering the projector defocusing levels.

中文翻译：

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基于优化的抖动条纹图案的复杂表面的三维形状测量

优化的抖动条纹图案是用于高速，高精度三维形状测量的一种有前途的方法。最近提出的抖动优化技术根据其目标函数在相域或强度域中优化条纹质量。基于阶段的优化是直接有效的，但对投影机的散焦水平很敏感。基于强度的优化对投影仪的散焦水平具有鲁棒性，但不能完全改善相位质量。实际上，难以控制散焦水平，因此获得高质量的条纹图案仍然是一个挑战，在不同的散焦水平下，条纹图案会影响测量质量。为了获得对散焦水平具有鲁棒性的高质量二进制抖动模式，本文提出了一种加权对象函数。此功能包括两个部分：整体强度部分和局部结构部分。总体强度测量基于归一化的均方误差。局部结构测量基于强度的残余误差。为了生成高质量的条纹图案，将权重对象功能应用于最佳补丁框架。仿真和实验结果均表明，在几乎集中的情况下，基于相位的优化方法和所提出的方法的性能要优于基于强度的优化方法。但是，基于相位的优化所产生的测量结果的质量会随着去模糊水平的提高而降低。所提出的方法对散焦水平具有鲁棒性，并且当投影机强烈散焦时仍可以减少相位误差。结合全局相似度和强度的局部残差，该方法可以得到不同散焦水平下的高质量二值抖动图像。它继承了二进制条纹图案的优点，因此不需要投影机的伽玛校准。在实践中，提出的方法可用于生成高质量的条纹图案。实验结果证明，该方法在不考虑投影仪散焦水平的情况下，可以获得较好的测量结果。