# 特征提取

## 特征点提取

* Harris角点检测：<https://senitco.github.io/2017/06/18/image-feature-harris/>

  > 计算图像周围的差异，如果两个方向的差异都很大，说明是一个具有两个主方向的点，这种差异可以用自相关矩阵的特征值描述，特征值计算麻烦，可以用矩阵的行列式和迹来间接表示。


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