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代码说明：

说明：  拉普拉斯高斯算子 拉普拉斯—高斯算子（Laplacian of Gaussian算子，通常缩写为log算子）是一种二阶微分算子，将在边缘处产生一个陡峭的零交叉。(Laplace Gaussian operator Laplace- Gaussian operator (Laplacian of Gaussian operator, often abbreviated as log operator) is a second-order differential operator, will be generated at the edge of a steep zero crossing.)