SEM图像分形维数的影响因素研究

Effect on Fractal Dimension of SEM Images

以玻璃光纤、碳纤维纸和两种机加工表面样本的扫描电子显微镜图像为对象,运用盒维法研究了不同的放大倍数和采集过程中受到的噪声干扰对分形维数的影响。研究结果表明,随着放大倍数增大或随着椒盐噪声密度和高斯随机噪声方差的减小,分形维数下降。放大倍数和噪声对分形维数都有较大影响。在扫描电子显微镜图像分形维数的计算中,可以依据试样的结构特征选择合适的放大倍数,进行去噪处理后再计算图像的分形维数。

Effect of magnification and noise on fractal dimension is studied by using box - counting method to scanning electron microscope （SEM） images of glass fiber, carbon paper and two samples of processed surfaces. It is found that fractal dimension decreases as magnification increases or salt -pepper noise density and Gaussian noise variance decreases. Fractal dimension is clearly affected by both magnification and noise. Magnification can be selected according to structural property and images can be processed by noise removal filter if necessary during fractal dimension calculation of SEM images.