计算图像的分形维数，盒子维。基于DBC（Differential Box-Counting）方法。结果表明，分形维数FD能够较好地刻画纹理图像的复杂程度。-Calculated image fractal dimension, box dimension. Based on DBC (Differential Box-Counting) method. The results show that the fractal dimension FD to better characterize th