Local patterns play an important role in statistical physics as well as in image processing. Two-dimensional ordinal patterns were studied by Ribeiro et al. who determined permutation entropy and complexity in order to classify paintings and images of liquid crystals. Here we find that the 2 by 2 patterns of neighboring pixels come in three types. The statistics of these types, expressed by two parameters, contains the relevant information to describe and distinguish textures. The parameters are most stable and informative for isotropic structures.

翻译：本地模式在统计物理学和图像处理中起着重要作用,Ribeiro等人研究了二维正统模式,他们决定了变异的酶和复杂性,以便对液体晶体的绘画和图像进行分类。在这里,我们发现相邻像素的2比2模式分为三类。以两个参数表示的这些类型的统计数据包含描述和区分质素的相关信息。参数对于异形结构来说最为稳定,信息最丰富。