基于二维直方图双斜率划分的快速Otsu图像分割算法

为了克服Otsu算法对图像分割的不足，本文在二维Otsu的基础上提出了基于二维直方图双斜率划分的快速Otsu分割算法，该算法将二维直方图上像素点之间关系转化为斜率值，构建斜率值与频率的一维直方图，利用双阈值Otsu对灰度斜率的一维直方图取双阈值，利用求出的双阈值（临界斜率）对图像二维直方图进行重新划分，对划分的图像二维直方图的有效区域，再次利用一维Otsu方法划分，从而得到最终结果。最后通过实验，验证此方法有较强的抗噪性，比二维Otsu方法计算效率高，处理效果好。

The rapid Otsu method based on two-dimensional histogram of double slope

In order to overcome the disadvantage of OTSU algorithm on image segmentation, this paper proposes a fast OTSU algorithm based on the dual-slope division of two-dimensional histogram. The algorithm transforms the relations of pixel points in a two-dimension histogram into slope values and builds a one-dimensional histogram of slope values and frequencies. By the use of a dual-threshold OTSU algorithm, the double threshold of the one-dimensional histogram of gray and slope values can be gotton. Then the two-dimensional histogram of image can be redistricted by the double threshold (critical slope). The final results can be got by using the one-dimensional Otsu algorithm again to divide the effective area of the redistricted two-dimensional histogram. The experiment results show that the proposed algorithm can achieve better anti-noise performance, computing efficiency, and processing effect than two-dimensional Otsu algorithm.