Abstract Fringe projection profilometry based on phase-shift method has been commonly used for three-dimensional measurement. However, measuring the specular surface is always a challenging task since the specular area cannot present original intensity information. This paper presents a novel framework for measuring objects with specular surfaces. Firstly, a set of phase-shifted fringe patterns with maximum intensity value is projected onto the specular surface. Then, the dichromatic reflection model is developed to theoretically decompose an image into specular and diffuse reflection components, which identifies specular pixels more robustly and effectively than judging by saturation only. Secondly, since the location and intensity of specular areas are acquired, the best projection intensity corresponding to the specular areas can be determined by fitting a power function that transforms captured specular reflection components to projected intensities, aiming to minimize specular areas and decrease specular reflection components. It should be stated here that the assumption based on this paper is that the fewer specular reflection components, the fewer measurement errors. Subsequently, the adaptive fringe patterns, which are constructed using the best projection intensity, are reprojected for phase recovery. Thirdly, it is reasonable that there still exist regions where the specular reflection components are too high. For these information-loss areas, the pixel inpainting technique is adopted when extracting the disparity map. Finally, the ultimate result combines adaptive fringe reconstruction with pixel inpainting. The experiment results verify that the proposed measurement framework can effectively and robustly perform three-dimensional reconstruction of various objects with specular surfaces.

中文翻译：

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基于双色反射模型的镜面 3D 形状测量的有效框架

摘要 基于相移法的条纹投影轮廓测量法已普遍用于三维测量。然而，测量镜面反射面始终是一项具有挑战性的任务，因为镜面反射面积无法呈现原始强度信息。本文提出了一种用于测量具有镜面的物体的新框架。首先，一组具有最大强度值的相移条纹图案被投影到镜面。然后，开发了二色反射模型，从理论上将图像分解为镜面反射和漫反射分量，与仅通过饱和度判断相比，它可以更稳健有效地识别镜面像素。其次，由于获得了镜面区域的位置和强度，对应于镜面区域的最佳投影强度可以通过拟合将捕获的镜面反射分量转换为投影强度的幂函数来确定，旨在最小化镜面区域并减少镜面反射分量。这里需要说明的是，基于本文的假设是镜面反射分量越少，测量误差越小。随后，使用最佳投影强度构建的自适应条纹图案被重新投影以进行相位恢复。第三，仍然存在镜面反射分量过高的区域是合理的。对于这些信息丢失区域，在提取视差图时采用像素修复技术。最后，最终结果将自适应条纹重建与像素修复相结合。实验结果验证了所提出的测量框架可以有效且稳健地对具有镜面的各种物体进行三维重建。