基于变窗口浮动阈值的调制结构光三维测量方法

Modified Structured Light 3D Measuring Method Based on Variable Window and Threshold

为了解决结构光三维测量中深度信息的准确提取问题，提出了基于变窗口浮动阈值的调制结构光三维测量方法。该方法根据调制结构光相位信息得到被测物体的深度信息，分析条纹图像灰度输出信息与条纹轮廓之间的关系，对每一像素点灰度值在选定窗口内建立周期函数，并对其在整个图像域内进行周期延拓，利用窗口内灰度的极值构造新的权函数，并以此权函数为依据对不同点分配权值，使窗口内各点灰度满足单调性，从而得到不同的选定阈值。实验结果表明，应用这种变窗口浮动阈值法可以得到很好的分割效果，用于沟槽槽深调制结构光三维测量时，标定后其测量结果的重复性优于0．4μm。

A modified structured light 3D measuring method based on variable window and threshold to resolve the problem of correctly obtaining depth information in 3D measurement was presented. The proposed method utilizes the phase information of the modified structured light to obtain the object depth information, analyzes the relationship between the image output information and the stripes contour, establishes periodical function in a selected window for every image point and continues it in the whole image flied, generates the weight function according to the extremum of grayscales .and distributes the different weight for different point to meet the needs of monotonicity in the window, and obtains different thresholds for different point in the window. The experimental results show that the proposed method can be used to correctly segment image, and the repeatability of 3D measurement for a groove is less than 0.4 μm after the system was calibrated.