基于分段垂直投影的水田秧苗列中心线提取

Center line extraction of paddy seedling row based on segmented vertical projection

为提取水田秧苗列中心线,提出了基于分段垂直投影的中心线提取方法.将彩色图像进行预处理后得到的二值图像在纵向方向分为上、中、下3段,从下段图像开始采用垂直投影法确定该段中各作物列左右边缘;在图像下段的每对左右边缘之间提取特征点并拟合临时直线,用每条直线和本段图像顶部的交点位置来确定中段中属于同一秧苗列的左右边缘点,再根据左右边缘点提取中段图像的特征点,在上段图像中以此类推,将所有特征点按不同秧苗列归入不同的点集;最后分别将每个点集中的特征点使用最小二乘法进行直线拟合.试验结果表明,该方法在分辨率为1280×1024像素的图像中提取离横向中心最近的3列秧苗中心线的准确率为94.50%,平均每幅耗时208 ms.

To extract the center line of paddy seedling row,an algorithm was proposed based on segmented vertical projection.The binary color image after preprocessing was divided into three sections of lower,middle and upper in the longitudinal direction.From the lower section,the vertical projection method was used to determine the edge around the crop row.The feature points between the left and right edges were extracted to fit a temporary line,and the intersection position of the line and the top of the section was used to determine the edge points belonging to the same crop row in the middle section.The same method was used in the upper section of the image,and all of the feature points were extracted into different sets of points according to different crop rows.The least square method was used to fit each point in the point set representing the crop row.The experimental results show that in the 1280×1024 pixel scolor image,the accuracy of the proposed method is 94.50%,and the average time of each frame is 208 ms.