基于多阈值和改进的Hough变换检测电表接线圆孔尺寸

针对智能电表接线圆孔尺寸自动检测的问题,提 出一种以多阈值分割方法为主体并基于改进的随机Hough变换的 圆检测方法。首先,实时获得包含所有智能电表接线圆孔并经裁剪的彩色图像,经图像灰度 化、滤波处理后,通过阈值分割 得到能够反应圆孔特征的二值图像。基于连通域标记算法准确将包含多个接线圆孔的图像自 动裁剪为至多包含一个真实接线 圆孔的多个子图像。其次,对于每个子图像,应用给定范围内的连续阈值进行Canny边界提 取,并通过改进的随机Hough变 换提取圆信息,进行圆累积。最后,根据峰值大小和位置提取有效圆及半径。对大量智能电 表接线圆孔图像进行实验的结果 表明,该方法能准确地提取出外观颜色、圆孔尺寸各异的接线圆孔,圆心坐标平均误差不超 过2个像素,圆半径平均误差不 超过2.5mm,是实时电表接线圆孔信息表征的新尝试。

Meter wiring hole size detection based on multi-threshold and improved Hough tr ansform

Due to the problem of automatic detection of smart meter wiring hole si ze,a circle detection method mainly based on multi-threshold method combined with improved randomized Hough transform is proposed in this paper.Firstly,after clipping, the color image containing all smart meter wiring holes is obtained in real-time.The binary image with hole features is obtained by threshold segmentation after image gray processing and filter proces sing.Based on the connected-domain labeling algorithm,the image containing multiple wiring holes can be accurately cut into a number of sub-images,and each sub-image contains at most one true wiring hole.Secondly,for each sub-image,we use the continuous thresholds in a given range to extract the Canny boundary,and extract the circle information by the improved randomized Hou gh transform.Finally,according to the peak size and position,we determine the ef fective cir cle and its radius.The experimental results show that the proposed method can ac curately extract the wiring holes with different background colors and different sizes of wiring holes.The average error of the c ircle center coordinates is not more than 2pixels,and the average error of the circle radius is not more than 2.5mm.