基于结构光焊缝图像预处理的研究

Study on Pre-process for Seam Image Based on Structured Light

为了可靠跟踪焊缝,需要对结构光视觉传感器采集的焊缝原始图像进行预处理,以消除噪声的影响.首先采用一维高斯型拉普拉斯滤波器处理图像,将尺寸与激光光带宽度相差较大的噪声变为离散的小块噪声,然后采用邻域均值滤波进行平滑处理.针对焊缝图像灰度分布随机变化的特点,采用最大方差阈值法自适应选取阈值分割图像,将图像二值化.采用标记法去除小区域噪声,获得清晰的焊缝图像,为后续提取焊缝特征奠定坚实基础.实验表明,该预处理方案可满足实时焊缝跟踪的需要.

To eliminate influence of noise and track seams reliably, it is required to pre-process the original images captured by vision sensor based on structured light. Firstly, one dimension Laplacian of Gaussian filter was applied to transform noises whose width was larger than laser light stripe to isolated and small noise. Then the image was smoothed with neighborhood median filter. Due to gray distribution variety of seam image, binary image was created with maximal square difference adaptive threshold, Acnode noise was cleared up by region labeling and selected threshold and obtained binary image of seam. Experiment indicates that this pre-process method satisfies requirement of real-time seam tracking.