论文标题
无监督的社区检测与Potts模型Hamiltonian,有效的算法解决方案以及数字病理学的应用
Unsupervised Community Detection with a Potts Model Hamiltonian, an Efficient Algorithmic Solution, and Applications in Digital Pathology
论文作者
论文摘要
使用Potts模型哈密顿式对大图的无监督分割是独一无二的,因为该分割由分辨率参数控制,该参数缩放了对小簇的敏感性。在这里,首先将输入图像建模为图,然后通过最大程度地减少图表和各个段上定义的Hamiltonian成本函数进行分割。但是,没有此优化的封闭形式解决方案,并且使用先前的迭代算法解决方案技术,问题在输入长度中二次缩放。因此,尽管Potts模型分割给出了准确的分割,但它被视为无监督的学习技术的严重未被充分利用。我们提出了基于各自的颜色特征对输入图像像素的快速统计下降采样,并提出了一种新的迭代方法,以最大程度地减少考虑像素与段关系的Potts模型能量。此方法是可推广的,可以扩展到图像像素纹理功能以及空间特征。我们证明了这种新方法高效,并且优于基于POTTS模型的图像分割的现有方法。我们证明了我们的方法在医学显微镜图像分割中的应用;特别是,在分割肾脏病理学中的肾肾小球微环境时。我们的方法不限于图像分割,可以将具有离散功能的任意数据集扩展到任何图像/数据分割/聚类任务。
Unsupervised segmentation of large images using a Potts model Hamiltonian is unique in that segmentation is governed by a resolution parameter which scales the sensitivity to small clusters. Here, the input image is first modeled as a graph, which is then segmented by minimizing a Hamiltonian cost function defined on the graph and the respective segments. However, there exists no closed form solution of this optimization, and using previous iterative algorithmic solution techniques, the problem scales quadratically in the Input Length. Therefore, while Potts model segmentation gives accurate segmentation, it is grossly underutilized as an unsupervised learning technique. We propose a fast statistical down-sampling of input image pixels based on the respective color features, and a new iterative method to minimize the Potts model energy considering pixel to segment relationship. This method is generalizable and can be extended for image pixel texture features as well as spatial features. We demonstrate that this new method is highly efficient, and outperforms existing methods for Potts model based image segmentation. We demonstrate the application of our method in medical microscopy image segmentation; particularly, in segmenting renal glomerular micro-environment in renal pathology. Our method is not limited to image segmentation, and can be extended to any image/data segmentation/clustering task for arbitrary datasets with discrete features.