Shape is described as the distribution of straight edge lines with specific properties such as position, length, orientation, width, contrast, steepness, and so on.

• 该方法用物体的边缘线段描述其形状特征，边缘线段具有多种属性，包括位置、长度、方向、宽度、边缘线段两端图像特征的对比度和倾斜度等。