中文说明：应用背景在图像处理中，经常用到四叉树的方法进行分割，这个代码可能为相关处理提供借鉴，文中部分代码可能需要稍微修改一下才能满足某项具体应用。关键技术如果是彩色图像，则转换为灰度图像，PicDivide中非零元素的位置，List为列向量，边长为最小值的块数与其他块的总数的比值，四叉树分割得到的块与图像面积的比。
English Description：
Application backgroundIn the image processing, four fork tree method is often used for segmentation, this code may provide reference for the relevant processing, the text of the code may need to be slightly modified to meet a specific application.Key TechnologyIf the color image, the conversion to gray image, PicDivide non zero element position, list as column vectors, the side length of the ratio of the minimum number of blocks and other blocks of the total, the quadtree segmentation obtained block and the image area ratio.