Setting Tangent Threshold的意思|示意

设置正切阈值 【Abstract】 An improved sub-pixel offset algorithm is studied. Setting tangent threshold,the gradient direction of edge is determined by the ratio and the positive or negative sign of partial differential. Then it inhibits pseudo-edge of the identified single-pixel wide edge points in gradient image. Finally,it carries on the quadratic parabolic interpolation of gradient amplitude function along its gradient direction,and calculate sub-pixel offset.