The algorithm uses direction masks based on classical Sobel masks in converting gray into gradient images and applies the polynomial interpolation to subpixel edge detecting at the gradient direction of edge on gradient images.

• 本算法应用在经典Sobel算子基础上构造出的方向模板；对灰度图像进行处理；得到梯度图像；然后在梯度图像上沿目标边缘的梯度方向进行多项式插值法亚像素细分计算；对目标边缘进行亚像素精确定位.