gradient image的用法和样例：
例句
- This algorithm is based on the watershed transform.First the gradient image is preprocessed according to the pixels intensity and spatial information.
该方法在分水岭算法的基础上，首先结合像素点亮度特征和空间分布特性应用自适应方法对梯度图像进行预处理。 - The pre-processing algorithm is made of image simplification and image morphologic gradient.The post-processing is mainly region merging.
预处理算法由图像简化和简化后的求梯度图像两个部分组成，后处理主要是区域合并。
